climate change in our life essay

Climate Change Essay for Students and Children

500+ words climate change essay.

Climate change refers to the change in the environmental conditions of the earth. This happens due to many internal and external factors. The climatic change has become a global concern over the last few decades. Besides, these climatic changes affect life on the earth in various ways. These climatic changes are having various impacts on the ecosystem and ecology. Due to these changes, a number of species of plants and animals have gone extinct.

When Did it Start?

The climate started changing a long time ago due to human activities but we came to know about it in the last century. During the last century, we started noticing the climatic change and its effect on human life. We started researching on climate change and came to know that the earth temperature is rising due to a phenomenon called the greenhouse effect. The warming up of earth surface causes many ozone depletion, affect our agriculture , water supply, transportation, and several other problems.

Reason Of Climate Change

Although there are hundreds of reason for the climatic change we are only going to discuss the natural and manmade (human) reasons.

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Natural Reasons

These include volcanic eruption , solar radiation, tectonic plate movement, orbital variations. Due to these activities, the geographical condition of an area become quite harmful for life to survive. Also, these activities raise the temperature of the earth to a great extent causing an imbalance in nature.

Human Reasons

Man due to his need and greed has done many activities that not only harm the environment but himself too. Many plant and animal species go extinct due to human activity. Human activities that harm the climate include deforestation, using fossil fuel , industrial waste , a different type of pollution and many more. All these things damage the climate and ecosystem very badly. And many species of animals and birds got extinct or on a verge of extinction due to hunting.

Effects Of Climatic Change

These climatic changes have a negative impact on the environment. The ocean level is rising, glaciers are melting, CO2 in the air is increasing, forest and wildlife are declining, and water life is also getting disturbed due to climatic changes. Apart from that, it is calculated that if this change keeps on going then many species of plants and animals will get extinct. And there will be a heavy loss to the environment.

What will be Future?

If we do not do anything and things continue to go on like right now then a day in future will come when humans will become extinct from the surface of the earth. But instead of neglecting these problems we start acting on then we can save the earth and our future.

Although humans mistake has caused great damage to the climate and ecosystem. But, it is not late to start again and try to undo what we have done until now to damage the environment. And if every human start contributing to the environment then we can be sure of our existence in the future.

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Home > Books > Environmental Issues and Sustainable Development

Impact of Climate Change on Life

Submitted: 05 June 2020 Reviewed: 18 October 2020 Published: 25 November 2020

DOI: 10.5772/intechopen.94538

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Environmental Issues and Sustainable Development

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Climate is changing in an accelerating pace. Climate change occurs as a result of an imbalance between incoming and outgoing radiation in the atmosphere. The global mean temperatures may increase up to 5.4°C by 2100. Climate change is mainly caused by humans, especially through increased greenhouse gas emissions. Climate change is recognized as a serious threat to ecosystem, biodiversity, and health. It is associated with alterations in the physical environment of the planet Earth. Climate change affects life around the globe. It impacts plants and animals, with consequences for the survival of the species. In humans, climate change has multiple deleterious consequences. Climate change creates water and food insecurity, increased morbidity/mortality, and population movement. Vulnerable populations (e.g., children, elderly, indigenous, and poor) are disproportionately affected. Personalized adaptation to the consequences of climate change and preventive measures are key challenges for the society. Policymakers must implement the appropriate strategies, especially in the vulnerable populations.

• climate change
• global warming
• animal survival
• human health
• vulnerable populations

Author Information

Hassan m. heshmati *.

• Endocrinology Metabolism Consulting, LLC, Anthem, AZ, USA

*Address all correspondence to: [email protected]

1. Introduction

Climate change has always happened on Earth but its rapid rate and important magnitude occurring now are of great concern. Climate change occurs as a result of an imbalance between incoming and outgoing radiation in the atmosphere. The global warming associated with climate change is different from past warming in its rate. It is anticipated that there will be a rise in global mean temperatures of up to 5.4°C by 2100. There is overwhelming evidence showing that human activities have contributed to climate change over the past century while changes in solar activity and volcanic eruptions have played a minor role. Over the last several decades, humans have engaged in large-scale transformation of natural systems causing a net accumulation of carbon dioxide in the atmosphere [ 1 , 2 , 3 , 4 , 5 ].

Climate change is recognized as a serious threat to ecosystem, biodiversity, and health. It is associated with alterations in the physical environment of the planet Earth and affects life around the globe [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 ].

Adaptation to the consequences of climate change and prevention of aggravation of climate change are key challenges for the society. Policymakers must implement personalized strategies, especially in the vulnerable populations [ 1 , 2 , 5 , 30 , 31 , 32 , 35 , 36 , 37 ].

Climate, from Ancient Greek “klima” (meaning inclination), is defined as the weather averaged over a long period (the standard period is 30 years).

The instrumental record of climate change is based on thousands of temperature and precipitation recording stations around the world.

3. Climate change versus global warming

Climate change and global warming are often used interchangeably but have distinct meanings and refer to different physical phenomena. Climate change includes warming and side effects of warming (e.g., heavy precipitation and increased wind speeds) while global warming refers only to long-term Earth’s rising global mean surface temperature.

4. Climate change causes

Climate change occurs as a result of an imbalance between incoming and outgoing radiation in the atmosphere. The increase in heat-trapping greenhouse gases (e.g., carbon dioxide, methane, and nitrous oxide) in the atmosphere raises Earth’s mean surface temperature. The levels of greenhouse gases are higher now than at any time in the last 800,000 years. As temperature increases, more water evaporates from the oceans and other water sources into the atmosphere, causing further increase of the temperature [ 1 , 2 , 3 , 4 , 5 ].

Atmospheric carbon dioxide comes from two primary sources, natural and anthropogenic (human-induced). Natural sources of carbon dioxide include most animals which exhale carbon dioxide as a waste product. Anthropogenic sources of carbon dioxide have been primarily driven by human activities since the early 20th century (industrial revolution), mainly fossil fuel burning (e.g., burning coal, oil, and natural gas), but also agricultural emissions and deforestation. The top 5 countries responsible for emissions of carbon dioxide are China, United States of America (USA), India, Russia, and Japan [ 4 ]. In 2017, the USA emitted approximately 5.1 billion metric tons of energy-related carbon dioxide for a global worldwide emission of approximately 32.5 billion metric tons. Deforestation of the Amazon in Brazil (loss of the equivalent of almost one million soccer fields of forest cover each year), mainly for agricultural purposes, is significantly contributing to climate change.

5. Climate change consequences

Climate change causes a cascade of side effects for the physical environment of the planet Earth and the living organisms on the globe ( Figure 1 ). All the changes in the physical planet Earth’s environment affect the life of plants, animals, and humans. Coral reefs, forests, and coastal human communities are particularly vulnerable to climate change. Some of the effects of climate change may be through the enhancement of the susceptibility to chemical pollution [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 ].

Climate change causes global changes of the planet.

Although most impacts of climate change are likely to be adverse, some health benefits may result in some regions. For example, warmer winters may reduce the number of temperature-related health events and death.

5.1 Physical planet Earth’s environment

According to the core accretion theory, planet Earth formed around 4.54 billion years ago (approximately one-third the age of the universe) by accretion from the solar nebula [ 38 ].

Planet Earth has faced climate change throughout its long history. The current climate change has multiple negative impacts on the physical planet Earth’s environment. It affects the frequency and severity of extreme events and natural disasters [ 1 , 4 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 19 ].

5.1.1 Temperature

Temperature records from modern thermometers (with temperature scales) have been available only since early 18th century. By studying indirect parameters (chemical and structural signatures), scientists can infer past temperatures.

At the creation of the universe, the temperature of the universe at 10 −35 second old was around 1 octillion°C. Within less than 2 minutes, the universe temperature cooled down to around 1 billion°C. Over at least the last several million years, planet Earth shifted between ice ages facing long cold periods (glacial) and warm periods (interglacial), on 100,000-year cycles.

The current climate change is associated with increased Earth’s temperature (land surfaces and upper layers of the ocean) ( Figure 2 ) [ 1 , 4 ]. Land surfaces are heating faster than ocean surfaces. A warmer atmosphere can hold more water vapor, leading to increased overall average precipitation [ 4 ]. Over the past 70 years, the Earth’s temperature has increased by approximately 0.7°C [ 4 ]. Since 1950, the number of cold days and nights has decreased while the number of warm days and nights has increased. Since 1976, the rate of warming has been greater than at any other time during the last 1,000 years. For any given period, there are extreme temperatures. In the past 20 years, Earth’s lowest air temperature was −94.7°C (recorded in Antarctica in 2010) and hottest air temperature was 70.7°C (recorded in Iran’s Lut Desert in 2005). The present global mean temperature is around 15.0°C. Currently, the surface temperatures are rising by approximately 0.2°C per decade [ 6 ]. According to the Intergovernmental Panel on Climate Change (IPCC) and based on different emissions scenarios, there will be a rise in global mean temperatures of 0.9 to 5.4°C by 2100 [ 4 ].

Climate change is associated with increased Earth’s temperature.

The rise in global mean temperature is not the same everywhere. There are regional variations in Earth’s temperature. Some areas will not even get warmer and may actually get cooler in the short term [ 4 ]. Warming is more pronounced at higher latitudes. The North Pole and Northern Hemisphere have warmed much faster than the South Pole and Southern Hemisphere. Greater temperature increases are expected in winter compared to summer and in nighttime versus daytime. Springs occur earlier and winters are milder.

5.1.2 Mountain glaciers and lakes

Climate change causes mountain glaciers to melt and accelerates the rate of ice loss on Earth in Greenland and Antarctica ( Figure 3 ). Some glaciers are sites of powerful sacred and symbolic meanings for local communities (e.g., in the Peruvian Andes, the Nepalese Himalayas, and the Chinese Meili Snow Mountains) [ 7 ].

Climate change causes melting of mountain glaciers.

Lakes around the world are freezing less and for a shorter duration. In few decades, thousands of lakes may lose their winter ice cover.

5.1.3 Sea levels

Climate change triggers rise in sea levels. The sea levels rise following either an increase in the volume of the water already in the ocean as water warms and expands or an increase in the mass of the water in the ocean mainly due to melting glaciers [ 4 ]. Since 1900, global mean sea level has increased by approximately 0.20 meter [ 4 ]. Over the last 25 years, the global mean see level rose on average by 0.003 meter per year [ 8 ]. By 2100, based on different emissions scenarios, sea levels are predicted to rise between 0.40 and 1.50 meters [ 4 ]. The sea-level rise will lead to disappearance of some islands and flooding with invasion of cities by water, leading to homelessness and population movement ( Figure 4 ).

Climate change triggers rise in sea levels .

The salty ocean water will challenge native plants and animals to adapt to the changing conditions. For humans, it causes salination of freshwater supplies and loss of productive farmlands [ 8 ]. Low-income countries (e.g., Bangladesh) are particularly impacted.

5.1.4 Hurricanes and rainstorms

Climate change promotes more dangerous hurricanes and heavier rainstorms due to warmer ocean water temperature ( Figure 5 ) [ 4 , 9 ]. The proportion of Category 4 and 5 hurricanes has increased at a rate of 25–30% per 1.0°C of global warming [ 9 ]. Hurricane Katrina (Category 5, New Orleans, USA, 2005) was one of the deadliest hurricanes in recent USA history. The total number of direct or indirect fatalities following hurricane Katrina was 1,833 (reports from state and local officials in five states). The 2019 North Atlantic hurricane season had six hurricanes (including three major hurricanes, e.g., Category 3 or higher).

Climate change promotes more dangerous hurricanes.

5.1.5 Wildfires

Climate change causes more frequent wildfires. The dry, hot weather has increased the intensity and destructiveness of forest fires in several countries (e.g., Brazil, USA, and Australia) ( Figure 6 ) [ 10 , 11 ]. Wildfires can cause deforestation, serious property damage, exposure of large populations to prolonged periods of polluted and toxic air with potential health impacts (e.g., respiratory diseases), and death. Amazon (Brazil) has become more flammable and vulnerable to wildfires during recent droughts [ 10 ]. California (USA) has experienced devastating autumn wildfires in recent years [ 11 ]; over 100 fatalities were directly attributed to the most destructive and deadliest wildfires that occurred in 2017 and 2018.

Climate change causes more frequent wildfires.

5.1.6 Droughts

Drought is a complex and multivariate phenomenon influenced by diverse physical and biological processes. Drought is among the most expensive natural disasters. Climate change is responsible for more frequent and severe droughts (especially in subtropical regions), promoting the expansion of deserts ( Figure 7 ) [ 4 , 12 ]. This will lead to misery, hunger, starvation, and population movement.

Climate change is responsible for more frequent and severe droughts.

5.1.7 Ocean acidity

The ocean provides most of the life-supporting environment on planet Earth. The abundance of carbon dioxide in the atmosphere is causing the surface waters of the oceans to become more acidic as some carbon dioxide dissolves into ocean water forming carbonic acid [ 4 ]. Ocean acidification can alter marine ecosystems with damage to coral reefs (source of many benefits for human communities), fish, and other aquatic species [ 4 , 13 ].

Climate change impacts plant phenology. Different climate change components are involved including atmospheric carbon dioxide level, temperature, sea level, rainfall, weeds, and pests or microbes [ 14 , 15 , 16 , 17 , 18 , 19 ].

5.2.1 Survival

Plant survival is affected by climate change ( Figure 8 ) [ 14 , 15 , 16 ]. The increased land surface temperature with the resulting mild winters promoting pest proliferation (e.g., allowing more pine beetles to survive), the invasion of farmlands by salty water, the wildfires, and the droughts compromise life of plants and lead to destruction of forests and damage to human agriculture. According to some reports, agriculture is the most endangered activity adversely affected by climate change. The decreased farming activity will lead to food insecurity.

Climate change challenges plant survival.

5.2.2 Blooming, pollination, and fructification

Plant growth, blooming, pollination, and fructification are impacted by climate change [ 17 , 18 , 19 ]. With the occurrence of shorter winters and warmer springs, plants bloom earlier for a shorter period and die younger ( Figure 9 ). Winter chill is essential for several fruit-producing trees. Insufficient chilling due to climate change can affect the productivity of fruit trees (e.g., less fruits, smaller fruits, and changes in color, texture, and taste of fruits) [ 17 , 18 ]. Around 75% of the production of seeds and fruits for human consumption depend on pollinators. Pollinators, especially bees, are facing unprecedented challenges for survival. With the lack of synchrony between plants and pollinators due to shift in seasons and the decline in the number of pollinators, the production of fruits is decreasing while the cost is significantly increasing.

Climate change is responsible for earlier blooming time of plants.

5.3 Animals

Climate change exposes animals to a variety of stressors, influencing metabolic and endocrine functions, with potential consequences for the survival of species [ 14 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 ]. With climate change, more animal species are going extinct every year. Approximately 700 mammals and birds are impacted. The degree of vulnerability varies by the type of animal and different species will be affected in different ways. Species with low tolerance for rising temperature are vulnerable to extinction. The vulnerable/endangered animals include polar bears, koalas, elephants, sea turtles, cheetahs, panda bears, and penguins (non-exhaustive list).

Species affected by climate change will either need to move to more suitable locations (e.g., higher elevations and latitudes) or to adapt to changes at their current locations (e.g., habitat, feeding and breeding patterns). If unable, they may perish and become extinct.

5.3.1 Habitat

Climate change can cause habitat degradation or loss for several species (e.g., polar bears, koalas, and birds). Polar bears are dependent on sea ice. The increased temperature is causing the arctic sea ice to melt, damaging the polar bears’ habitat ( Figure 10 ) [ 23 ]. Koalas are dependent on eucalyptus tree. The increased temperature and drought are causing wildfire, destroying the koalas’ habitat [ 24 ]. Lake Urmia (Iran) is a bird habitat and used to be a popular tourist destination. The lake is drying up mainly because of climate change.

Climate change causes loss of habitat for polar bear.

5.3.2 Nutrition

Survival of species can be affected by water/food availability/quality beyond those that species can tolerate. Unpredictability/shortage of water and food caused by climate change may lead to greater prevalence of torpor and hibernation in small mammals and hypometabolism in large mammals.

Polar bears will have trouble finding food as the sea ice thins and melts earlier. With limited food supply, the polar bears rely on their stored fat. They have to swim longer distances in the water and many young cubs die because of their inability to swim. Koalas’ main food source is eucalyptus leaves. Each koala eats approximately 1 kg of eucalyptus leaves per day. Climate change reduces the amount of water in the eucalyptus tree. The increased carbon dioxide level causes decrease protein levels in the tree affecting plant nutritional quality. All these changes create dehydration, malnutrition, and starvation. Koalas are risking their lives by climbing down from their trees in search of water and food. This leaves them vulnerable to predators and the risk of being hit by cars. Koalas’ population has declined by more than 30% over their last three generations ( Figure 11 ) [ 24 ]. Elephants require 150–300 liters of water per day for drinking in addition to the amount needed for bathing and playing. Droughts can cause population decline ( Figure 12 ) [ 25 ].

Climate change is responsible for dehydration and malnutrition of koala.

Climate change causes decline in elephant population.

5.3.3 Migration, breeding, and gender determination

Warmer springs have promoted advanced timing of migration and breeding in most avian species in the last decades ( Figure 13 ) [ 26 ]. Rising sea levels threaten the sea turtle eggs as most turtles lay their eggs on beaches. Climate change can affect sex determination in several animals [ 27 , 28 ]. The sex of the sea turtles is determined by the nest temperatures. Cool temperatures produce more males while warm temperatures produce more females. Climate change alters the sea turtles’ gender population (females outnumbering males). Certain areas could end up producing only female turtles, with the possibility of local species extinction since there will be no mating partners for female turtles ( Figure 14 ).

Climate change promotes early avian migration.

Climate change leads to female sea turtle overpopulation and domination.

Climate change is a major threat to human existence. It has multiple deleterious health consequences leading to increased morbidity and mortality [ 1 , 2 , 3 , 5 , 8 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 ].

5.4.1 Temperature

The human core temperature averages 37.0°C and is tightly controlled within a range of 33.2°C and 38.2°C to ensure optimal physiological function. Extreme deviations from the normal core temperature, i.e., a decrease below 27.0°C (hypothermia) or an increase above 42.0°C (hyperthermia) can be fatal [ 5 ]. Climate change is resulting in increased exposures to intense heat in many parts of the world. With increase temperature, there are physiological reactions in humans creating risks for some organs and exposing individuals to increased morbidity and mortality (e.g., reduced performance and work productivity, behavioral changes, heat exhaustion, heat stroke, respiratory failure, myocardial infarction, stroke, and death) ( Figure 15 ) [ 5 , 29 , 30 , 31 ]. The reduced work productivity (up to 10% in some hot areas) has large economic consequences. Without adaptation, the economic losses of reduced work productivity could be more than 20% of the gross domestic product by 2100. Children, elderly people, poor people, outdoor workers, workers required to wear protective clothing and/or personal protective equipment, and subjects with chronic health conditions are at higher risk when facing heat stress. In the USA, the annual heat-related death is approximately 1,500. The European heat wave during the summer of 2003 caused as many as 70,000 deaths.

Climate change through heat wave can cause increased morbidity and mortality.

On the upside, increased temperatures by allowing milder winters can lower the incidence and mortality of some winter-related events such as myocardial infarction and stroke. Also, hotter and drier conditions can reduce the incidence of some infectious diseases (e.g., malaria).

5.4.2 Nutrition

Climate change creates water and food insecurity/shortage with significant impact on hygiene, nutrition, and food safety in several countries ( Figure 16 ) [ 1 , 8 , 32 , 33 ]. In the absence of proper desalination of drinking water impacted by increased salinity following sea-level rise (especially in low-income countries like Bangladesh), the high exposure to salt through drinking water, food, and bathing can lead to several health problems (e.g., hypertension and skin diseases) [ 8 ]. In many regions, food production systems are negatively impacted by climate change [ 1 ]. According to the International Rice Research Institute in the Philippines, 1.0°C rise in night-time temperature can reduce rice yields by 10%. With the ocean temperature rise, several fish populations may move to higher latitudes, affecting dietary protein supplies of millions of people.

Climate change can create human undernutrition.

5.4.3 Infection

Climate change through variations in temperature, precipitation/humidity, wind, and solar radiation influences the spread of some infectious diseases since these variations may impact the survival, reproduction, and distribution of disease pathogens and vectors/hosts as well as their transmission environment. Several infectious diseases are involved including malaria, dengue, and Lyme disease ( Figure 17 ) [ 3 , 34 ].

Climate change favors spread of infectious diseases.

5.4.4 Population movement

Climate change by creating unsuitable living conditions (e.g., desertification, sea-level rise, decline in freshwater availability, food shortage, health issues) will move many people (forced displacement, planned resettlement, migration). Poor communities are particularly impacted by the human movement. It is estimated that by 2050, up to several hundred million persons will be moved ( Figure 18 ) [ 32 ]. Population movement will expose countries to multiple challenges (e.g., social, health, and financial consequences and violent conflicts).

Climate change causes population movement.

5.4.5 Vulnerable populations

Overall, children, elderly, indigenous groups, poor individuals, outdoor workers, remote populations, and subjects with pre-existing conditions are disproportionately affected by climate change ( Figure 19 ) [ 1 , 2 , 5 , 30 , 31 , 32 , 35 , 36 , 37 ].

Climate change disproportionately impacts vulnerable populations.

Low-income and geographically vulnerable countries (e.g., Bangladesh) are most affected by the health consequences of climate change (at least in its earlier stages). However, in higher-income countries (e.g., USA), there is also a high vulnerability in some ethnic and socio-economic groups as demonstrated by the Chicago heatwave of 1995 and the New Orleans hurricane Katrina of 2005. According to the World Health Organization, the global mortality in 2004 as a result of climate change was around 141,000 of which 85% were children. The mortality of the European heat wave of 2003 affected mainly the elderly.

6. Climate change adaptation in animals

Adaptive evolution of phenotypes to climate change has been the subject of several investigations [ 26 , 39 ].

Animals react to climate change in three ways: to move, to adapt, or to die. Moving to a new territory is not always a simple solution and can create new challenges (e.g., interaction with unfamiliar species and more competition for food).

Some animals can adapt to changing conditions. An interesting example of adaptation to climate change is the case of polar bears. With the change in climate, polar bears who usually used seal pubs and other marine mammals as food, have started hunting animals available on land (e.g., snow geese and caribou). However, there is no proof that the change in diet can support the polar bear population in the long run. Another example of adaptation to climate change is with migrating birds. As spring arrives earlier, insects emerge earlier. Some migrating birds are laying their eggs earlier to match insect availability for their young.

7. Climate change adaptive and preventive strategies

Adaptation to deleterious consequences of climate change and prevention of aggravation of climate change are important components of the global response of the society [ 1 , 2 , 3 , 5 , 16 , 18 , 31 , 32 , 35 , 36 , 37 , 40 ].

Adaptation (spontaneous or planned) is especially important in developing countries. Policymakers must implement personalized adaptive strategies, especially in the vulnerable populations. The risk control to population health cannot be implemented efficiently at the local level alone. It requires coordinated international policy. Human beings rely on biodiversity and functioning ecosystems for water, food, and health. If other species are unable to adapt to climate change, the consequences for humans could be extremely serious. Adaptive strategies require investment and skills. Society needs to implement strategies to help wildlife adapt to the impacts of climate change (e.g., wildlife overpass and drinking stations). Identification of traits contributing to resilience and vulnerability of species will allow the development of efficient conservation action plans.

Prevention (long-term strategies) is a key approach. To spare species and protect humans, the greenhouse gas emissions should be reduced as soon as possible. If we drastically reduce greenhouse gas emissions, our climate may reach a new and potentially acceptable equilibrium. Development and deployment of low-carbon energy technologies, policies to reduce fossil fuel burning, forest preservation, and reforestation should be promoted. Carbon sequestration, by capturing and storing atmospheric carbon dioxide, can decrease the amount of carbon dioxide in the atmosphere and reduce climate change. More energy-efficient homes and vehicles using alternative energies from sun, wind, and waves are needed. Increased use of public transportation, cycling, and walking should be promoted. It is also helpful if humans could reduce the consumption of animal-based food (red meat) and switch to plant-based diet (fruits and vegetables). This type of dietary change can have multiple health, environmental, and economic benefits.

Numerous countries work together under the umbrella of the United Nations Framework Convention on Climate Change. The recommendation of the IPCC is to keep the global warming below 1.5°C to avoid irreversible damages. Unfortunately, in some countries, extensive political lobbying denying the contribution of humans to climate change and creating political barrier to pro-environmental policies has emerged. In 2015, all United Nations countries negotiated the Paris Agreement aiming to keep global warming well below 2.0°C [ 41 ]. Almost all countries signed the treaty. However, in 2017, the USA decided to withdraw from the Paris Agreement.

8. Climate change cost

Climate change, through its multiple consequences, has a very high cost for the society and significantly affects the economic growth.

The estimates of total direct damage of hurricane Katrina were up to $125 billion and the cost of California wildfires of 2017 and 2018 exceeded $40 billion. It is estimated that the cost of climate change for USA economy can reach hundreds of billions of dollars a year by 2090.

Adaptive and preventive strategies need important financial investments. The cost of halting global warming and reducing greenhouse gas emission to very low levels by 2050 will be around $50 trillion. At the current greenhouse gas emission rate, the budget for keeping the global warming below 1.5°C would be exhausted by 2028.

9. Climate change and future of life on planet Earth

Climate change is a serious threat for our planet. The number of relatively undisturbed ecosystems is decreasing rapidly. Climate change seriously affects the viability of many plant and animal species, and human health. Climate change may become one of the major drivers of species extinction in the 21st century.

The Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) releases regular reports on biodiversity written by hundreds of experts from all regions of the world. The reports found that biodiversity is declining in every region of the world, endangering economies, livelihoods, food security, and quality of life. In the words of the IPBES chair, “the time for action was yesterday or the day before”.

According to scientists, we have approximately a decade to keep carbon dioxide from reaching catastrophic levels that can cause irreversible damages. If no efficient preventive action is undertaken, by the year 2050, 15 to 37% of existing plant and animal species are predicted to become extinct and by the year 2100, half of all species may experience extinction.

10. Conclusions

It is widely accepted that the climate is changing in an accelerating pace. Climate change is affecting every aspect of life. It is recognized as a serious threat to ecosystem, biodiversity, and health.

Adaptation to health consequences of climate change and prevention of aggravation of climate change are key challenges for the society. The health sector should promote research, education (for health personnel), and information (for public and policymakers) on climate change and its consequences.

Adaptation requires multiple measures at various levels. Policymakers must implement personalized adaptive strategies, especially in the vulnerable populations.

Climate change impacts can be mitigated by reducing greenhouse gas emissions and by enhancing the capacity of Earth’s land surface to absorb greenhouse gases from the atmosphere. Long-term investment in renewable energy and energy efficiency is urgently needed.

Conflict of interest

The author declares no conflict of interest.

• 1. McMichael AJ, Lindgren E. Climate change: Present and future risks to health, and necessary responses. Journal of Internal Medicine. 2011; 270 :401-413. DOI: 10.1111/j.1365-2796.2011.02415.x
• 2. McMichael AJ. Globalization, climate change, and human health. The New England Journal of Medicine. 2013; 368 :1335-1343. DOI: 10.1056/NEJMra1109341
• 3. Wu X, Lu Y, Zhou S, Chen L, Xu B. Impact of climate change on human infectious diseases: Empirical evidence and human adaptation. Environment International. 2016; 86 :14-23. DOI: 10.1016/j.envint.2015.09.007
• 4. Hsiang S, Kopp RE. An economist’s guide to climate change science. Journal of Economic Perspectives. 2018; 32 :3-32. DOI: 10.1257/jep.32.4.3
• 5. Ahima RS. Global warming threatens human thermoregulation and survival. The Journal of Clinical Investigation. 2020; 130 :559-561. DOI: 10.1172/JCI135006
• 6. Sobrino JA, Julien Y, García-Monteiro S. Surface temperature of the planet Earth from satellite data. Remote Sensing. 2020; 12 :218. DOI: 10.3390/rs12020218
• 7. Allison EA. The spiritual significance of glaciers in an age of climate change. WIREs Climate Change. 2015; 6 :493-508. DOI: 10.1002/wcc.354
• 8. Vineis P, Chan Q , Khan A. Climate change impacts on water salinity and health. Journal of Epidemiology and Global Health. 2011; 1 :5-10. DOI: 10.1016/j.jegh.2011.09.001
• 9. Holland G, Bruyère CL. Recent intense hurricane response to global climate change. Climate Dynamics. 2014; 42 :617-627. DOI: 10.1007/s00382-013-1713-0
• 10. Brando P, Macedo M, Silvério D, et al. Amazon wildfires: Scenes from a foreseeable disaster. Flora. 2020; 268 :151609. DOI: 10.1016/j.flora.2020.151609
• 11. Goss M, Swain DL, Abatzoglou JT, et al. Climate change is increasing the likelihood of extreme autumn wildfire conditions across California. Environmental Research Letters. 2020; 15 :094016. DOI: 10.1088/1748-9326/ab83a7
• 12. Cook BI, Mankin JS, Anchukaitis KJ. Climate change and drought: From past to future. Current Climate Change Reports. 2018; 4 :164-179. DOI: 10.1007/s40641-018-0093-2
• 13. Hoegh-Guldberg O, Poloczanska ES, Skirving W, Dove S. Coral reef ecosystems under climate change and ocean acidification. Frontiers in Marine Science. 2017; 4 :158. DOI: 10.3389/fmars.2017.00158
• 14. Wiens JJ. Climate-related local extinctions are already widespread among plant and animal species. PLOS Biology. 2016; 14 :e2001104. DOI: 10.1371/journal.pbio2001104
• 15. Karimi V, Karami E, Keshavarz M. Climate change and agriculture: Impacts and adaptive responses in Iran. Journal of Integrative Agriculture. 2018; 17 :1-15. DOI: 10.1016/S2095-3119(17)61794-5
• 16. Raza A, Razzaq A, Mehmood SS, et al. Impact of climate change on crops adaptation and strategies to tackle its outcome: A review. Plants. 2019; 8 :34. DOI: 10.3390/plants8020034
• 17. Rai R, Joshi S, Roy S, Singh O, Samir M, Chandra A. Implications of changing climate on productivity of temperate fruit crops with special reference to apple. Journal of Horticulture. 2015; 2 :1000135. DOI: 10.4172/2376-0354.1000135
• 18. Houston L, Capalbo S, Seavert C, Dalton M, Bryla D, Sagili R. Specialty fruit production in the Pacific Northwest: Adaptation strategies for a changing climate. Climatic Change. 2018; 146 :159-171. DOI: 10.1007/s10584-017-1951-y
• 19. De LC. Impact of climate change on floriculture and landscape gardening. International Journal of Agriculture Sciences. 2018; 10 :6253-6256
• 20. Jenssen BM. Endocrine-disrupting chemicals and climate change: A worst-case combination for arctic marine mammals and seabirds. Environmental Health Perspectives. 2006; 114 (Suppl 1):76-80. DOI: 10.1289/ehp.8057
• 21. Noyes PD, Lema SC. Forecasting the impacts of chemical pollution and climate change interactions on the health of wildlife. Current Zoology. 2015; 61 :669-689
• 22. Fuller A, Maloney SK, Blache D, Cooper C. Endocrine and metabolic consequences of climate change for terrestrial mammals. Current Opinion in Endocrine and Metabolic Research. 2020; 11 :9-14. DOI: 10.1016/j.coemr.2019.12.003
• 23. Wilson RR, Regehr EV, Rode KD, St Martin M. Invariant polar bear habitat selection during a period of sea ice loss. Proceedings of the Royal Society B. 2016; 283 :20160380. DOI: 10.1098/rspb.2016.0380
• 24. Narayan EJ, Williams M. Understanding the dynamics of physiological impacts of environmental stressors on Australian marsupials, focus on the koala ( Phascolarctos cinereus ). 2016; 1 :2. DOI: 10.1186/s40850-016-0004-8
• 25. Ngcobo JN, Nedambale TL, Nephawe KA, Sawosz E, Chwalibog A. The future survival of African elephants: Implications for conservation. International Journal of Avian & Wildlife Biology. 2018; 3 :379-384. DOI: 10.15406/ijawb.2018.03.00123
• 26. Charmantier A, Gienapp P. Climate change and timing of avian breeding and migration: Evolutionary versus plastic changes. Evolutionary Applications. 2014; 7 :15-28. DOI: 10.1111/eva.12126
• 27. DeCourten BM, Brander SM. Combined effects of increased temperature and endocrine disrupting pollutants on sex determination, survival, and development across generations. Scientific Reports. 2017; 7 :9310. DOI: 10.1038/s41598-017-09631-1
• 28. Jensen MP, Allen CD, Eguchi T, et al. Environmental warming and feminization of one of the largest sea turtle populations in the world. Current Biology. 2018; 28 :154-159. DOI: 10.1016/j.cub.2017.11.057
• 29. Huang C, Barnett AG, Wang X, Vaneckova P, FitzGerald G, Tong S. Projecting future heat-related mortality under climate change scenarios: A systematic review. Environmental Health Perspectives. 2011; 119 :1681-1690. DOI: 10.1289/ehp.1103456
• 30. Lundgren K, Kuklane K, Gao C, Holmér I. Effects of heat stress on working populations when facing climate change. Industrial Health. 2013; 51 :3-15
• 31. Kjellstrom T, Briggs D, Freyberg C, Lemke B, Otto M, Hyatt O. Heat, human performance, and occupational health: A key issue for the assessment of global climate change impacts. Annual Review of Public Health. 2016; 37 :97-112. DOI: 10.1146/annurev-publhealth-032315-021740
• 32. McMichael C, Barnett J, McMichael AJ. An III wind? Climate change, migration, and health. Environmental Health Perspectives. 2012; 120 :646-654. DOI: 10.1289/ehp.1104375
• 33. Lake IR, Hooper L, Abdelhamid A, et al. Climate change and food security: Health impacts in developed countries. Environmental Health Perspectives. 2012; 120 :1520-1526. DOI: 10.1289/ehp.1104424
• 34. Liang L, Gong P. Climate change and human infectious diseases: A synthesis of research findings from global and spatio-temporal perspectives. Environment International. 2017; 103 :99-108. DOI: 10.1016/j.envint.2017.03.011
• 35. Sheffield PE, Landrigan PJ. Global climate change and children’s health: Threats and strategies for prevention. Environmental Health Perspectives. 2011; 119 :291-298. DOI: 10.1289/ehp.1002233
• 36. Ford JD. Indigenous health and climate change. American Journal of Public Health. 2012; 102 :1260-1266. DOI: 10.2105/AJPH.2012.300752
• 37. Lesnikowski AC, Ford JD, Berrang-Ford L, Paterson JA, Barrera M, Heymann SJ. Adapting to health impacts of climate change: A study of UNFCCC Annex I parties. Environmental Research Letters. 2011; 6 :044009. DOI: 10.1088/1748-9326/6/4/044009
• 38. Co’Neill HS. The origin of the moon and the early history of the earth – A chemical model. Part 2: The earth. Geochimica et Cosmochimica Acta. 1991; 55 :1159-1172
• 39. Merilä J, Hendry AP. Climate change, adaptation, and phenotypic plasticity: The problem and the evidence. Evolutionary Applications. 2014; 7 :1-14. DOI: 10.1111/eva.12137
• 40. Springmann M, Godfray HCJ, Rayner M, Scarborough P. Analysis and valuation of the health and climate change cobenefits of dietary change. PNAS. 2016; 113 :4146-4151. DOI: 10.1073/pnas.1523119113
• 41. Dimitrov RS. The Paris Agreement on climate change: Behind closed doors. Global Environmental Politics. 2016; 16 :1-11. DOI: 10.1162/GLEP_a_00361

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution 3.0 License , which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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• ENVIRONMENT

How global warming is disrupting life on Earth

The signs of global warming are everywhere, and are more complex than just climbing temperatures.

Our planet is getting hotter. Since the Industrial Revolution—an event that spurred the use of fossil fuels in everything from power plants to transportation—Earth has warmed by 1 degree Celsius, about 2 degrees Fahrenheit.  

That may sound insignificant, but 2023 was the hottest year on record , and all 10 of the hottest years on record have occurred in the past decade.  

Global warming and climate change are often used interchangeably as synonyms, but scientists prefer to use “climate change” when describing the complex shifts now affecting our planet’s weather and climate systems.  

Climate change encompasses not only rising average temperatures but also natural disasters, shifting wildlife habitats, rising seas , and a range of other impacts. All of these changes are emerging as humans continue to add heat-trapping greenhouse gases , like carbon dioxide and methane, to the atmosphere.

What causes global warming?

When fossil fuel emissions are pumped into the atmosphere, they change the chemistry of our atmosphere, allowing sunlight to reach the Earth but preventing heat from being released into space. This keeps Earth warm, like a greenhouse, and this warming is known as the greenhouse effect .  

Carbon dioxide is the most commonly found greenhouse gas and about 75 percent of all the climate warming pollution in the atmosphere. This gas is a product of producing and burning oil, gas, and coal. About a quarter of Carbon dioxide also results from land cleared for timber or agriculture.  

Methane is another common greenhouse gas. Although it makes up only about 16 percent of emissions, it's roughly 25 times more potent than carbon dioxide and dissipates more quickly. That means methane can cause a large spark in warming, but ending methane pollution can also quickly limit the amount of atmospheric warming. Sources of this gas include agriculture (mostly livestock), leaks from oil and gas production, and waste from landfills.  

What are the effects of global warming?  

One of the most concerning impacts of global warming is the effect warmer temperatures will have on Earth's polar regions and mountain glaciers. The Arctic is warming four times faster than the rest of the planet. This warming reduces critical ice habitat and it disrupts the flow of the jet stream, creating more unpredictable weather patterns around the globe.  

( Learn more about the jet stream. )

A warmer planet doesn't just raise temperatures. Precipitation is becoming more extreme as the planet heats. For every degree your thermometer rises, the air holds about seven percent more moisture. This increase in moisture in the atmosphere can produce flash floods, more destructive hurricanes, and even paradoxically, stronger snow storms.  

The world's leading scientists regularly gather to review the latest research on how the planet is changing. The results of this review is synthesized in regularly published reports known as the Intergovernmental Panel on Climate Change (IPCC) reports.  

A recent report outlines how disruptive a global rise in temperature can be:

• Coral reefs are now a highly endangered ecosystem. When corals face environmental stress, such as high heat, they expel their colorful algae and turn a ghostly white, an effect known as coral bleaching . In this weakened state, they more easily die.  
• Trees are increasingly dying from drought , and this mass mortality is reshaping forest ecosystems.
• Rising temperatures and changing precipitation patterns are making wildfires more common and more widespread. Research shows they're even moving into the eastern U.S. where fires have historically been less common.
• Hurricanes are growing more destructive and dumping more rain, an effect that will result in more damage. Some scientists say we even need to be preparing for Cat 6 storms . (The current ranking system ends at Cat 5.)

How can we limit global warming?  

Limiting the rising in global warming is theoretically achievable, but politically, socially, and economically difficult.  

Those same sources of greenhouse gas emissions must be limited to reduce warming. For example, oil and gas used to generate electricity or power industrial manufacturing will need to be replaced by net zero emission technology like wind and solar power. Transportation, another major source of emissions, will need to integrate more electric vehicles, public transportation, and innovative urban design, such as safe bike lanes and walkable cities.  

( Learn more about solutions to limit global warming. )

One global warming solution that was once considered far fetched is now being taken more seriously: geoengineering. This type of technology relies on manipulating the Earth's atmosphere to physically block the warming rays of the sun or by sucking carbon dioxide straight out of the sky.

Restoring nature may also help limit warming. Trees, oceans, wetlands, and other ecosystems help absorb excess carbon—but when they're lost, so too is their potential to fight climate change.  

Ultimately, we'll need to adapt to warming temperatures, building homes to withstand sea level rise for example, or more efficiently cooling homes during heat waves.  

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• ENVIRONMENT AND CONSERVATION
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What Is Climate Change?

Climate change is a long-term change in the average weather patterns that have come to define Earth’s local, regional and global climates. These changes have a broad range of observed effects that are synonymous with the term.

Changes observed in Earth’s climate since the mid-20th century are driven by human activities, particularly fossil fuel burning, which increases heat-trapping greenhouse gas levels in Earth’s atmosphere, raising Earth’s average surface temperature. Natural processes, which have been overwhelmed by human activities, can also contribute to climate change, including internal variability (e.g., cyclical ocean patterns like El Niño, La Niña and the Pacific Decadal Oscillation) and external forcings (e.g., volcanic activity, changes in the Sun’s energy output , variations in Earth’s orbit ).

Scientists use observations from the ground, air, and space, along with computer models , to monitor and study past, present, and future climate change. Climate data records provide evidence of climate change key indicators, such as global land and ocean temperature increases; rising sea levels; ice loss at Earth’s poles and in mountain glaciers; frequency and severity changes in extreme weather such as hurricanes, heatwaves, wildfires, droughts, floods, and precipitation; and cloud and vegetation cover changes.

“Climate change” and “global warming” are often used interchangeably but have distinct meanings. Similarly, the terms "weather" and "climate" are sometimes confused, though they refer to events with broadly different spatial- and timescales.

What Is Global Warming?

Global warming is the long-term heating of Earth’s surface observed since the pre-industrial period (between 1850 and 1900) due to human activities, primarily fossil fuel burning, which increases heat-trapping greenhouse gas levels in Earth’s atmosphere. This term is not interchangeable with the term "climate change."

Since the pre-industrial period, human activities are estimated to have increased Earth’s global average temperature by about 1 degree Celsius (1.8 degrees Fahrenheit), a number that is currently increasing by more than 0.2 degrees Celsius (0.36 degrees Fahrenheit) per decade. The current warming trend is unequivocally the result of human activity since the 1950s and is proceeding at an unprecedented rate over millennia.

Weather vs. Climate

“if you don’t like the weather in new england, just wait a few minutes.” - mark twain.

Weather refers to atmospheric conditions that occur locally over short periods of time—from minutes to hours or days. Familiar examples include rain, snow, clouds, winds, floods, or thunderstorms.

Climate, on the other hand, refers to the long-term (usually at least 30 years) regional or even global average of temperature, humidity, and rainfall patterns over seasons, years, or decades.

Find Out More: A Guide to NASA’s Global Climate Change Website

This website provides a high-level overview of some of the known causes, effects and indications of global climate change:

Evidence. Brief descriptions of some of the key scientific observations that our planet is undergoing abrupt climate change.

Causes. A concise discussion of the primary climate change causes on our planet.

Effects. A look at some of the likely future effects of climate change, including U.S. regional effects.

Vital Signs. Graphs and animated time series showing real-time climate change data, including atmospheric carbon dioxide, global temperature, sea ice extent, and ice sheet volume.

Earth Minute. This fun video series explains various Earth science topics, including some climate change topics.

Other NASA Resources

Goddard Scientific Visualization Studio. An extensive collection of animated climate change and Earth science visualizations.

Sea Level Change Portal. NASA's portal for an in-depth look at the science behind sea level change.

NASA’s Earth Observatory. Satellite imagery, feature articles and scientific information about our home planet, with a focus on Earth’s climate and environmental change.

Header image is of Apusiaajik Glacier, and was taken near Kulusuk, Greenland, on Aug. 26, 2018, during NASA's Oceans Melting Greenland (OMG) field operations. Learn more here . Credit: NASA/JPL-Caltech

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Facts About Earth

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What is climate change and why does it matter?

Climate change is the defining issue of our time . We have reached a pivotal moment in deciding our planet's future.

Find out what climate change is, why it matters and what it could mean for our collective future.

What are weather, climate and climate change?

Weather refers to atmospheric conditions, such as rain or snow, happening in a place at a specific moment in time. Climate is how much, on average, a type of weather will occur over a longer period.

Dr Joeri Rogelj is a climate scientist at Imperial College London's Grantham Institute who has contributed to and led several major climate change assessments. He explains, 'Climate change is how the characteristics of the weather we experience in a certain place change.

'It can get hotter or wetter on average or have more concentrated rain in a short period, but then get longer dry periods. All of that can be a result of climate change.'

Global warming is a term used interchangeably with climate change, although the latter is preferred because the warming atmosphere and oceans are just some of the effects we see.

'It's not just about temperature. Places are also becoming wetter or drier, and in some the seasons are moving. Most importantly, in a few regions and seasons, it may actually at times be cooler than we're used to. That's confusing if you just talk about global warming.'

This is Typhoon Utor, which affected the Philippines and China in 2013. It caused considerable damage and loss of life. Climate change influences most weather events, including tropical storms and hurricanes. © NASA Goddard Space Flight Center via Flickr ( CC BY 2.0 )

Causes of climate change

The main driver of current climate change is the emission of greenhouse gases, most importantly carbon dioxide and methane . These are primarily released when fossil fuels are burnt. Meat and dairy production, producing cement and some industrial processes, such as the production and use of fertilisers, also emit greenhouse gases.

Greenhouse gases trap heat in our atmosphere. Since the mid-nineteenth century , the world has emitted over 2.2 trillion tonnes of carbon dioxide.

Joeri explains, 'Energy from the Sun falls on our planet and normally gets reflected back as infrared radiation. But instead of escaping back out into space, this radiation gets absorbed by molecules of greenhouse gases, which then emit them in all directions.'

This process causes more heat to be kept near Earth's surface, warming our world.

How do we know climate is changing?

There are measuring stations all around the world that keep track of air and sea temperature. From these measurements it's clear that temperatures are rising.

'There are many more indicators that tell us that the Earth is warming. For example, on a warming planet we would expect polar ice caps and glaciers to melt. It is clearly observed that those are melting,' explains Joeri.

This image of an iceberg in McMurdo Sound was captured in 2017 as part of NASA's Operation IceBridge. This is an ongoing airborne mission to monitor changes in polar ice. © NASA Goddard Space Flight Center via Flickr ( CC BY 2.0 )

We know that greenhouse gases are causing change. Thanks to studies that look at how carbon dioxide absorbs infrared radiation, for example, there is a scientific understanding of how the planet would warm as a result of emissions. This has allowed climate scientists to discount the theory that global warming is being caused by an increase in the Sun's intensity, for example.

It's also known that greenhouse gases are primarily emitted by fossil fuel combustion.

'To burn carbon and produce carbon dioxide, you need oxygen. The amount of oxygen that is in the atmosphere is reducing at exactly the right amount for the increase in carbon dioxide to be caused by combusting fossil fuels,' explains Joeri.

There is additional evidence in the ratios of different types of carbon. Fossil fuels are, essentially, ancient plants . Plants now and in the past preferentially take up carbon-12. In normal conditions, the ratio between carbon-12 and carbon-13 is constant.

'What we can see is that the ratio of carbon-13 in our atmosphere is going down at exactly the rate you would predict if the carbon dioxide increase was due to burning fossil fuels.'

Scientists predict that climate change will cause extreme weather events such as wildfires, floods and hurricanes to become worse ©  Quarrie Photography via Flickr ( CC BY-NC-ND 2.0 )

Effects of climate change

Climate change does not have the same effects everywhere. The planet is generally getting hotter, but some regions and seasons can at times be temporarily cooler. Some places will see drawn-out seasons, while others may experience concentrated bursts of extreme weather.

Extreme weather events - such as hurricanes, floods, heatwaves , drought and  wildfires  - are predicted to become more intense and frequent.

'Pretty much any weather event is influenced by climate change. As scientists we can estimate how much climate change has made a certain event more likely or more intense than it would have been without climate change,' explains Joeri.

When the world warms, ice melts. Arctic sea ice could disappear entirely in a warming world, and Greenland and Antarctica's ice sheets could be destabilised. This would result in large sections melting, which would add more liquid to the ocean. 

Sea level rise caused by climate change is a threat to low lying islands such as Panama's idyllic San Blas Islands, 49 of which are inhabited © Marc Veraart via Flickr ( CC BY-ND 2.0 )

Ice also reflects the Sun's energy, so without ice, more heat is absorbed by the ocean . Water expands as it warms - this is known as thermal expansion. This effect means that the ocean takes up more space, causing sea levels to rise. Even with rapid emission cuts, sea levels are expected to rise by around 26 to 53 centimetres by 2100.

Along with melting ice sheets and glaciers, rising global temperatures could cause rainforests to die and widespread species extinctions.

The effects of climate change on us

How climate change will affect you depends on who you are and where you live.

Around 190 million people currently live in areas that, due to rising sea levels, are expected to be under high tide levels by 2100. This could cause a massive displacement of populations. Low lying atoll nations such as Tuvalu and the Maldives are incredibly vulnerable to this change and could be lost to the sea.

Hundreds of millions of people rely on seafood as their main source of protein. Warming and more acidic waters could destroy marine food chains by affecting their base, such as krill or coral reefs .

Longer-lasting drought could devastate crops, threating food security. Reservoirs drying up , as well as the loss of glaciers, could make drinking water scarce. 

Pasterze Glacier is estimated to be receding at a rate of 10 metres per year. A sign shows where the glacier lay in 1995, with the ice having since dramatically retreated up the valley. ©  H Raab via Flickr ( CC BY-NC-ND 2.0 )

Increased precipitation can cause deadly flooding, as well as lowering indoor air quality. This could affect our health as dampness benefits moulds and fungi.

Around four billion people live in urban areas, and by 2050 this will have risen to an estimated 6.7 billion.

City dwellers are not exempt from climate change's effects. Urban populations usually rely on rural areas for inputs such as food and water. If climate change disrupts these important connections, it could heavily affect those in urban areas.

Natural disasters impact poor and vulnerable populations disproportionately hard and clearly expose the consequences of ignoring social inequalities . With extreme weather increasing, these populations face a heightened level of risk.

For example, the urban heat island effect amplifies the effects of temperature extremes in cities. Those unable to afford to buy and run air conditioning may find their health compromised.

The hazards of climate change also do  disproportionate harm to women and girls .

Joeri says, 'We don't know what will happen when, exactly. It's really hard to anticipate, particularly for populations that are already on the edge every year.'

People are also seeing climate change impact their mental health, experiencing a phenomenon known as eco-anxiety . 

Differences in wealth, ethnicity and health are just some of the inequalities that could determine a person's vulnerability to the effects of climate change © Kompas/Hendra A Setyawan via World Meteorological Organization Flickr ( CC BY-NC-ND 2.0 )

How does climate change affect biodiversity?

The natural world is delicately balanced . No species - including ours - is completely independent of all others. A 2019 report confirmed that over one million animal and plant species are now at risk of extinction as a result of human activities.

In the UK, an analysis of over 700 species has shown that more than 80% of trends between 1976 and 2005 indicate seasonal events are happening earlier. Differing rates of change could mean that species' lives are no longer synchronised with those they rely on.

Many plants are flowering earlier. Migrating birds arrive earlier, leave later and some even are getting smaller . Butterflies are emerging earlier . Birds and amphibians are laying their eggs earlier in the year. Some species are moving into new areas, such as kelps which form vital marine habitats.

Seaweeds are important for many reasons . They act as vital habitats. Some also help protect coastlines from erosion.

Insects are one of the most vulnerable groups, with less ability than mammals or birds to escape warmer temperatures. Loss of insects, which are a primary food source for many animals, a key pollinator of plants and whose numbers are already plummeting , could cause the ecosystem to collapse.

In aquatic ecosystems, activities to mitigate the side effects of climate change, such as building hard flood defences, can have negative effects. As sea levels rise, sea walls reduce the space for intertidal ecosystems. A rising sea could also damage important coastal habitats like sand dunes and cliffs.

Joeri says, 'The ocean looks homogenous, but it also experiences variations. There are ocean heatwaves, where if a particularly warm mass of water comes to an area like coral reefs, it induces loss and mass dieback.'

The loss of Arctic sea ice takes away a key habitat from animals including polar bears, seals and walruses. The ice is now declining at a rate of more than 12% per decade .

Climate change is just one of the stressors currently impacting nature. Sea use, invasive species, pollution and the exploitation of organisms are all factors in the threat to nature. Without drastic changes , it's expected that there will be devastating changes in biodiversity and ecosystems.

Find out more about the link between climate change and the biodiversity crisis . 

A warming planet and melting ice threatens the survival of iconic animals such as polar bears © Gary Kramer/USFWS via U.S. Fish and Wildlife Service Flick r ( CC BY 2.0 )

Is there any hope for the future?

Climate change has been a known problem for around 30 years. Starting to fix it earlier might have made this daunting task much easier.

Joeri says, 'We definitely know how to reduce emissions to a significant degree. We are seeing more impacts of climate change, but we can also see a heightened interest and concern in the general public.

'Ultimately, reducing emissions is really an issue of public and political will.'

By understanding more about the planet, such as by studying the poles, scientists are able to estimate the consequences climate change will have © NASA Goddard Space Flight Center via Flickr ( CC BY 2.0 )

Over the past decades, scientists have estimated the potential impacts of the planet's average temperature rising by different amounts.

'Based on that information, governments have come together and decided that they don't want to exceed a 2°C rise. They want to be well below that and pursue efforts to make it as close as possible to 1.5 °C.'

The difference in outcomes between 1.5 and 2°C are considerable. The impacts are the difference of 70% or 99% of coral reefs dying or a summer free of Arctic sea ice once every 100 or 10 years.

Scientists have determined how much carbon dioxide can still be emitted before this temperature rise limit will be exceeded. This is called the carbon budget and it's relatively small.

Joeri says, 'It's currently 420 to 580 billion tonnes of carbon dioxide for having a two-in-three or a one-in-two chance of limiting warming to 1.5°C, starting to count in 2018.

'Today we are roughly emitting 42 billion tonnes a year. So, if you start today and are going to net-zero emissions , if you want a one-in-two chance, we should there by around mid-century.

'These numbers define the geophysical requirement. Scientists then use engineering and economic models to understand how we can transform society to stay within that emission limit.'

There are many ways that you can help the planet . One way is by reducing the amount of meat and dairy you eat. © Theo Stikkelman via Flickr ( CC BY 2.0 )

This transformation could include changes such as increasing the share of energy produced by renewables , changing the way food is produced , changing our diets to have a lower carbon footprint and changing the way we build houses and design cities .

Moving to net-zero emissions will not be a perfectly co-ordinated transition . It will take some countries to lead and show the world that moving to this new way of living and functioning is both possible and beneficial for other sustainability objectives, such as public health and food security.

But on whether we'll ever see a change for the better, Joeri says he's hopeful.

'Preferably we would have started 25 or 30 years ago, but I will take any year at which we start declining steadily towards net-zero.'

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We're working towards a future where both people and the planet thrive.

Hear from scientists studying human impact and change in the natural world.

Do your bit for nature

Small actions can make a big difference.

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Climate change is already altering everything, from fertility choices to insuring our homes

Climate change is already changing the way many of us live or think. Image:  Unsplash/Alexander Tsang

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Stay up to date:, pandemic preparedness and response.

• Climate change is already affecting people’s lives in a variety of ways.
• Global warming is the biggest health threat facing humanity, the World Health Organization says.
• It’s also making people rethink family planning choices and putting properties at risk of becoming uninsurable.
• Disruptions to supply chains because of extreme weather are shaking the global economy.

How is climate change affecting you?

You may think the biggest impacts lie far away – in terms of time or geography. But global warming is already changing the way many of us live or think.

1. Health suffers because of climate change

Climate change is the biggest health threat facing humanity , the World Health Organization says, estimating that it will cause around a quarter of a million additional deaths each year in 2030-50. These will mainly be from malnutrition, malaria, diarrhoea and heat stress.

However, climate change is already having more subtle effects on health and wellbeing. Spring is beginning earlier in many places, meaning there’s a higher pollen count. This is bad news for allergy sufferers. Higher temperatures in the United States made the pollen season 11-27 days longer between 1995 and 2011, the Asthma and Allergy Foundation of America says.

Rising temperatures also contribute to worsening air quality, which can increase the risk and severity of asthma attacks .

2. Climate change is raising the cost of living

COVID-19 has received most of the blame for recent global supply chain problems, but climate change is also having an impact. When supply chains are shaken, this impacts the availability and cost of goods.

Freezing weather in Texas in February 2021 triggered the United States’ most severe energy blackout of all time, leading to shutdowns at three major semiconductor plants and adding to the global shortage of microchips.

The cost of living is also soaring because of the global surge in energy prices. While Russia’s war on Ukraine is driving much of this now, climate change is also a factor.

“ Companies face up to $120 billion in costs from environmental risks in their supply chains by 2026,” according to research published in 2021 by CDP, a nonprofit that runs the world's largest environmental disclosure system. This will include increased costs for raw materials, and because of regulatory changes such as carbon pricing as the world addresses environmental crises, the report says.

In 2021, more than 20% of American adults lived in households unable to pay their utility bills .

3. Warming oceans are threatening our way of life

Sea level rises could pose the biggest threat to global supply chains , potentially putting ports and coastal infrastructure out of action. Higher sea temperatures may also cause more severe storms in tropical parts of the world, posing a threat to life and infrastructure.

The sea is home to most of our biodiversity, and 3 billion people globally rely on it for their livelihoods, according to the UN. However, carbon emissions from human activity are causing ocean warming, acidification and oxygen loss , putting large numbers of marine-related jobs at risk, it says.

Climate change poses an urgent threat demanding decisive action. Communities around the world are already experiencing increased climate impacts, from droughts to floods to rising seas. The World Economic Forum's Global Risks Report continues to rank these environmental threats at the top of the list.

To limit global temperature rise to well below 2°C and as close as possible to 1.5°C above pre-industrial levels, it is essential that businesses, policy-makers, and civil society advance comprehensive near- and long-term climate actions in line with the goals of the Paris Agreement on climate change.

The World Economic Forum's Climate Initiative supports the scaling and acceleration of global climate action through public and private-sector collaboration. The Initiative works across several workstreams to develop and implement inclusive and ambitious solutions.

This includes the Alliance of CEO Climate Leaders, a global network of business leaders from various industries developing cost-effective solutions to transitioning to a low-carbon, climate-resilient economy. CEOs use their position and influence with policy-makers and corporate partners to accelerate the transition and realize the economic benefits of delivering a safer climate.

Contact us to get involved.

4. People might have fewer babies

People are increasingly citing the climate crisis as a major reason why they may decide to have fewer or even no children. According to a study in the United States, a third of women said they will reduce their anticipated family size because of it.

However a similar number of the more than 2,800 American women surveyed by Modernfertility.com said the issue has made them decide to have children sooner . The study says this is because it’s either made them focus more on what’s important to them or given them a sense of urgency.

5. Your property could become uninsurable

Insurance is something that nearly everyone has, but climate change poses a “systemic risk” to the sector, according to professional services company Grant Thornton.

Extreme weather events led to insured losses of $105 billion in 2021 , the fourth-highest level since 1970, according to preliminary estimates by Swiss Re, one of the world's leading providers of reinsurance and insurance.

This not only potentially makes insurance more expensive for everyone, but it also means some assets could become uninsurable . One in 25 Australian homes could be uninsurable by 2030 , according to the Climate Council.

6. Increased chance of another pandemic

Climate change makes new pandemics more likely, because as temperatures increase, wild animals will be forced to change habitats. This could lead to them living nearer to human populations, increasing the chances of a virus jumping between species and causing the next pandemic, according to a report published by the scientific journal Nature.

“Geographic range shifts” will mean mammals encounter each other for the first time, and in doing so will share thousands of viruses, the report says. Even keeping global warming under 2°C this century “will not reduce future viral sharing”, the scientists note.

What is the World Economic Forum doing about fighting pandemics?

The first human trial of a COVID-19 vaccine was administered this week.

CEPI, launched at the World Economic Forum, provided funding support for the Phase 1 study. The organization this week announced their seventh COVID-19 vaccine project in the fight against the pandemic.

The Coalition for Epidemic Preparedness Innovations (CEPI) was launched in 2017 at the Forum's Annual Meeting – bringing together experts from government, business, health, academia and civil society to accelerate the development of vaccines against emerging infectious diseases and to enable access to these vaccines during outbreaks.

Coalitions like CEPI are made possible through public-private partnerships. The World Economic Forum is the trusted global platform for stakeholder engagement, bringing together a range of multistakeholders from business, government and civil society to improve the state of the world.

Organizations can partner with the Forum to contribute to global health solutions. Contact us to find out how.

The World Economic Forum is committed to helping limit global warming to 1.5°C above pre-industrial levels to stave off catastrophe. It aims to work with leaders to increase climate commitments, collaborate with partners to develop private initiatives, and provide a platform for innovators to realize their ambition and contribute solutions.

Have you read?

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License and Republishing

World Economic Forum articles may be republished in accordance with the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International Public License, and in accordance with our Terms of Use.

The views expressed in this article are those of the author alone and not the World Economic Forum.

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A weekly update of the most important issues driving the global agenda

.chakra .wef-1dtnjt5{display:-webkit-box;display:-webkit-flex;display:-ms-flexbox;display:flex;-webkit-align-items:center;-webkit-box-align:center;-ms-flex-align:center;align-items:center;-webkit-flex-wrap:wrap;-ms-flex-wrap:wrap;flex-wrap:wrap;} More on Climate Action .chakra .wef-17xejub{-webkit-flex:1;-ms-flex:1;flex:1;justify-self:stretch;-webkit-align-self:stretch;-ms-flex-item-align:stretch;align-self:stretch;} .chakra .wef-nr1rr4{display:-webkit-inline-box;display:-webkit-inline-flex;display:-ms-inline-flexbox;display:inline-flex;white-space:normal;vertical-align:middle;text-transform:uppercase;font-size:0.75rem;border-radius:0.25rem;font-weight:700;-webkit-align-items:center;-webkit-box-align:center;-ms-flex-align:center;align-items:center;line-height:1.2;-webkit-letter-spacing:1.25px;-moz-letter-spacing:1.25px;-ms-letter-spacing:1.25px;letter-spacing:1.25px;background:none;padding:0px;color:#B3B3B3;-webkit-box-decoration-break:clone;box-decoration-break:clone;-webkit-box-decoration-break:clone;}@media screen and (min-width:37.5rem){.chakra .wef-nr1rr4{font-size:0.875rem;}}@media screen and (min-width:56.5rem){.chakra .wef-nr1rr4{font-size:1rem;}} See all

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New to Climate Change?

What can be done about climate change.

It is not too late to take action on climate change.

The Science

Given what we know about the threats that climate change poses to humans, we must take swift action. As a global community, we need to soon level off—and then decrease—the amount of carbon dioxide (CO 2 ) and other greenhouse gases in the atmosphere. The faster we do this, the less damage we will cause to our world and our way of life.

Stopping the Rise in CO2

The fastest way to address the buildup of CO 2 in the atmosphere is to stop adding more. Many vital parts of our economy emit huge amounts of greenhouse gases: the way we generate electricity and heat for our buildings and industry; the oil we burn to power our cars, trucks and planes; the refrigerants we use to preserve our food and cool our buildings; and the intensive manufacturing processes for making concrete and steel .

And yet there are many ways to reduce the CO 2 from these sectors. We can replace high-emitting fuels like coal, oil and gas with nearly “carbon-free” alternatives, such as solar power , wind power , or nuclear power . We can capture the CO 2 from fossil fuel power and manufacturing plants and store it underground. We can also update our buildings and infrastructure, so that it takes less energy to build and use them.

We can add to these efforts by trying to remove some of the CO 2 that is already in the atmosphere: for instance, by reforesting the Earth, by changing our farming practices to store more carbon in the soil , or through “direct air capture” technology. However, these methods will likely not be able to remove CO 2 quicker than we are now adding it to the atmosphere. We must begin with stopping our runaway greenhouse gas emissions.

Adapting to Change

Because human activity has already added such a large amount of greenhouse gases to the atmosphere, the world is now experiencing the early effects of climate change. We need to prepare for and adapt to these changes, so that we can protect human health, water and food supplies, our cities and towns , and natural habitats. A new field of work has emerged to reinforce coastlines to shield them from rising oceans , grow new crops to match regions’ changing climates, protect our infrastructure from wildfires and hurricanes , and plan for shifting supplies of water and food.

Today, these tasks are still manageable. If we get ahead of the regional changes we know are coming, and if we put the needs of the poorest and most vulnerable first, very few parts of the world will be irreparably damaged by the climate change we have already caused.

But unless we also actively cut our greenhouse gas emissions, unchecked climate change could eventually put safe and just adaptation beyond our reach. This possibility has led some scientists to study more extreme and controversial options, like geoengineering; for example, there are proposals that would try to artificially cool the Earth to counter some of the effects of climate change. Urgent action is needed to avoid the need for these riskier options.

Driving Solutions

Great progress can and must be achieved with the low-carbon technologies we have today. And all of us can help speed the pace at which these technologies take root and spread. Individuals can change their behavior and advocate for ambitious new policies. Corporations can drive change across whole industries. Governments can enact laws to make it easier and cheaper to cut greenhouse gas emissions, and to help communities prepare for new challenges. And intergovernmental agreements such as the Paris Agreement have already created a strong framework for international cooperation and aggressive action, if governments around the world step up their commitments .

At the same time, the world does not have a true alternative to fossil fuels that can meet all our current energy needs, let alone meet an increased demand in the future. We severely lack the suite of solutions to address climate change at an economic and social cost that we can agree to bear.

A tremendous amount of work is taking place at MIT and other scientific and engineering institutions around the world to develop these options, in collaboration with the industries and communities that can deploy and scale them. But to quicken the pace of technological breakthroughs, policymakers need to set the stage now for game-changing advances in multiple fields of science, technology, and policy. To take on the hardest challenges in reducing our emissions, in removing CO 2 from the atmosphere, and in adapting to a changing climate, we urgently need new tools.

Seizing the Opportunity

The MIT community fundamentally agrees that climate change presents grave risks that demand society’s urgent attention. The challenge requires an aggressive and pragmatic plan to achieve a net zero carbon global energy system, the sooner the better, for all of humankind.

If academia, business, government, and citizens act together toward this common goal, we can create a pollution-free energy system; form a prosperous, adaptable and resilient society; keep human, animal, and plant life flourishing; and create a better world for ourselves and generations to come.

You may notice that we, the writers on this site, use the word “we” to collectively refer to those who have benefitted in various ways from burning fossil fuels, those who will face the impacts of climate change, and those whose responsibility it is to act. We did this intentionally to create a sense of community in addressing this challenge. However, we acknowledge that people and groups across the globe have not equally benefitted from the use of fossil fuels, and many – including young people and future generations – will disproportionately endure the consequences. We, those who are affiliated with MIT and those who live in developed countries, are often among those whose activities have historically had a disproportionate impact on climate change. Therefore, we see that we have a greater responsibility – as professionals, citizens, community members, and consumers – to act to reverse its course.

Beef up your knowledge on specific climate change impacts and solutions with our quick explanations about clean energy, climate models, and much more, written by MIT experts.

Have Questions?

Whether it's simple or sticky, about science or solutions, ask us! We work with MIT faculty and scientists to get you clear, no-nonsense answers grounded in the best scientific information.

Tinker Around

Create your own set of climate change solutions in this online simulator from Climate Interactive and MIT Sloan’s Sustainability Initiative.

Take a Course

Extend your learning with edX's online courses on clean energy, food security, sustainable architecture, protecting health and many more.

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Essay on Climate Change

Climate Change Essay - The globe is growing increasingly sensitive to climate change. It is currently a serious worldwide concern. The term "Climate Change" describes changes to the earth's climate. It explains the atmospheric changes that have occurred across time, spanning from decades to millions of years. Here are some sample essays on climate change.

100 Words Essay on Climate Change

200 words essay on climate change, 500 words essay on climate change.

The climatic conditions on Earth are changing due to climate change. Several internal and external variables, such as solar radiation, variations in the Earth's orbit, volcanic eruptions, plate tectonics, etc., are to blame for this.

There are strategies for climate change reduction. If not implemented, the weather might get worse, there might be water scarcity, there could be lower agricultural output, and it might affect people's ability to make a living. In order to breathe clean air and drink pure water, you must concentrate on limiting human activity. These are the simple measures that may be taken to safeguard the environment and its resources.

The climate of the Earth has changed significantly over time. While some of these changes were brought on by natural events like volcanic eruptions, floods, forest fires, etc., many of the changes were brought on by human activity. The burning of fossil fuels, domesticating livestock, and other human activities produce a significant quantity of greenhouse gases. This results in an increase of greenhouse effect and global warming which are the major causes for climate change.

Reasons of Climate Change

Some of the reasons of climate change are:

Deforestation

Excessive use of fossil fuels

Water and soil pollution

Plastic and other non biodegradable waste

Wildlife and nature extinction

Consequences of Climate Change

All kinds of life on earth will be affected by climate change if it continues to change at the same pace. The earth's temperature will increase, the monsoon patterns will shift, the sea level will rise, and there will be more frequent storms, volcano eruptions, and other natural calamities. The earth's biological and ecological equilibrium will be disturbed. Humans won't be able to access clean water or air to breathe when the environment becomes contaminated. The end of life on this earth is imminent. To reduce the issue of climate change, we need to bring social awareness along with strict measures to protect and preserve the natural environment.

A shift in the world's climatic pattern is referred to as climate change. Over the centuries, the climate pattern of our planet has undergone modifications. The amount of carbon dioxide in the atmosphere has significantly grown.

When Did Climate Change Begin

It is possible to see signs of climate change as early as the beginning of the industrial revolution. The pace at which the manufacturers produced things on a large scale required a significant amount of raw materials. Since the raw materials being transformed into finished products now have such huge potential for profit, these business models have spread quickly over the world. Hazardous substances and chemicals build up in the environment as a result of company emissions and waste disposal.

Although climate change is a natural occurrence, it is evident that human activity is turning into the primary cause of the current climate change situation. The major cause is the growing population. Natural resources are utilised more and more as a result of the population's fast growth placing a heavy burden on the available resources. Over time, as more and more products and services are created, pollution will eventually increase.

Causes of Climate Change

There are a number of factors that have contributed towards weather change in the past and continue to do so. Let us look at a few:

Solar Radiation |The climate of earth is determined by how quickly the sun's energy is absorbed and distributed throughout space. This energy is transmitted throughout the world by the winds, ocean currents etc which affects the climatic conditions of the world. Changes in solar intensity have an effect on the world's climate.

Deforestation | The atmosphere's carbon dioxide is stored by trees. As a result of their destruction, carbon dioxide builds up more quickly since there are no trees to absorb it. Additionally, trees release the carbon they stored when we burn them.

Agriculture | Many kinds of greenhouse gases are released into the atmosphere by growing crops and raising livestock. Animals, for instance, create methane, a greenhouse gas that is 30 times more potent than carbon dioxide. The nitrous oxide used in fertilisers is roughly 300 times more strong than carbon dioxide.

How to Prevent Climate Change

We need to look out for drastic steps to stop climate change since it is affecting the resources and life on our planet. We can stop climate change if the right solutions are put in place. Here are some strategies for reducing climate change:

Raising public awareness of climate change

Prohibiting tree-cutting and deforestation.

Ensure the surroundings are clean.

Refrain from using chemical fertilisers.

Water and other natural resource waste should be reduced.

Protect the animals and plants.

Purchase energy-efficient goods and equipment.

Increase the number of trees in the neighbourhood and its surroundings.

Follow the law and safeguard the environment's resources.

Reduce the amount of energy you use.

During the last few decades especially, climate change has grown to be of concern. Global concern has been raised over changes in the Earth's climatic pattern. The causes of climate change are numerous, as well as the effects of it and it is our responsibility as inhabitants of this planet to look after its well being and leave it in a better condition for future generations.

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• Published: 10 May 2024

Talking about climate change and health

Nature Climate Change volume  14 ,  page 409 ( 2024 ) Cite this article

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• Climate change
• Environmental social sciences
• Public health

The climate crisis is also an urgent and ongoing health crisis with diverse human impacts leading to physical, mental and cultural losses. Translating knowledge into action involves broad collaboration, which relies heavily on careful communication of a personal and politicized issue.

Against a backdrop of reported historical peaks in monthly temperatures, the past months have seen increasing visibility of the issue of climate change health, as several institutions have pushed awareness, research and action to limit the effects that warming has on human health. These include the inaugural Declaration on Climate and Health at COP28, the publication of the report Quantifying the Impact of Climate Change on Human Health 1 by the World Economic Forum, and a pledge of £23 million by the Wellcome Trust to support transdisciplinary research to protect human health from climate change.

In this issue of Nature Climate Change and an associated online Focus , we highlight research and other content at the climate–health intersection.

Across these works, a clear and familiar theme that arises is the world’s current lack of preparation to deal with the ongoing crisis. This is exemplified in an Analysis by Braithwaite and colleagues of the ability of healthcare systems to cope with climate change. In line with the World Economic Forum’s finding that climate impacts will cost healthcare systems a further US$1.1 trillion globally by 2050 (ref. 1 ), Braithwaite and colleagues highlight the need for multi-pronged plans to future-proof these at-risk systems. They also demonstrate the heavy bias of current research on acute disaster events and in the Global North.

The second conspicuous theme is that responding to the climate–health crisis will involve diverse actors. In a Viewpoint article, six researchers highlight key issues in their fields, which include mental health, labour, disease spread, maternal and neonatal health, air quality and nutrition, while advocating the need for collaboration across disciplines, sectors and geography. Echoing this need for collaboration, a Feature article by Yessenia Funes on the public drive to seek climate action through the courts focuses on the varied yet complementary roles the public, research scientists, healthcare professionals and lawyers have to play.

Thirdly, and critically linked to the previous points, is that improved communication is key for translating research into action. Part of this involves learning the languages of different fields or sectors: in a Q&A article, Maria Neira, director of the Department of Environment, Climate Change and Health at the World Health Organization (WHO), describes how understanding that the climate terms ‘adaptation’ and ‘mitigation’ corresponded to the terms ‘primary intervention’ and ‘secondary intervention’ in public health helped to align communication between the two fields. Another part also involves ensuring that language is used carefully to support positive action. Psychologist Elizabeth Marks (writing in the Viewpoint article) discusses the importance of identifying eco-anxiety without pathologizing it, while Neira discusses the impact of communicating a negative message (that is, climate change is harming human health) with or without actionable plans, underscoring the difference between problem solving and panic. Funes also highlights the important role of health practitioners, whose personal relationships with patients makes them ‘trusted messengers’ to discuss climate change health information. In line with this, the WHO has just released a new toolkit to support healthcare professionals to effectively communicate about climate change and health 2 . A Comment from Noa Heiman in this issue also discusses the best ways for therapists to support their clients who experience climate distress.

Overall, talking about climate change health is not just a question of slipping from the technical jargon of climate models to that of healthcare or legal systems. It is also about communicating with an increasingly engaged public on a deeply personal and politicized issue. Finding the right wording is therefore extremely important. But the personal part of health is also what makes discussing climate change from a health point of view such a powerful tool to move forward.

An ongoing global crisis lacking preparedness that requires multiple actors to move forward can leave a lot of room for debate. But as Neira suggests, if instead of talking only about reducing emissions or limiting the amount of degrees warming, we discuss the number of lives that can be saved, there is less room for discussion, and more room to translate words into action.

Quantifying the Impact of Climate Change on Human Health (World Economic Forum, 2024).

WHO launches new toolkit empowering health professionals to tackle climate change. WHO (22 March 2024); https://go.nature.com/3w1i7yO

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Talking about climate change and health. Nat. Clim. Chang. 14 , 409 (2024). https://doi.org/10.1038/s41558-024-02020-3

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What Are the Causes of Climate Change?

We can’t fight climate change without understanding what drives it.

Low water levels at Shasta Lake, California, following a historic drought in October 2021

Andrew Innerarity/California Department of Water Resources

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At the root of climate change is the phenomenon known as the greenhouse effect , the term scientists use to describe the way that certain atmospheric gases “trap” heat that would otherwise radiate upward, from the planet’s surface, into outer space. On the one hand, we have the greenhouse effect to thank for the presence of life on earth; without it, our planet would be cold and unlivable.

But beginning in the mid- to late-19th century, human activity began pushing the greenhouse effect to new levels. The result? A planet that’s warmer right now than at any other point in human history, and getting ever warmer. This global warming has, in turn, dramatically altered natural cycles and weather patterns, with impacts that include extreme heat, protracted drought, increased flooding, more intense storms, and rising sea levels. Taken together, these miserable and sometimes deadly effects are what have come to be known as climate change .

Detailing and discussing the human causes of climate change isn’t about shaming people, or trying to make them feel guilty for their choices. It’s about defining the problem so that we can arrive at effective solutions. And we must honestly address its origins—even though it can sometimes be difficult, or even uncomfortable, to do so. Human civilization has made extraordinary productivity leaps, some of which have led to our currently overheated planet. But by harnessing that same ability to innovate and attaching it to a renewed sense of shared responsibility, we can find ways to cool the planet down, fight climate change , and chart a course toward a more just, equitable, and sustainable future.

Here’s a rough breakdown of the factors that are driving climate change.

Natural causes of climate change

Human-driven causes of climate change, transportation, electricity generation, industry & manufacturing, agriculture, oil & gas development, deforestation, our lifestyle choices.

Some amount of climate change can be attributed to natural phenomena. Over the course of Earth’s existence, volcanic eruptions , fluctuations in solar radiation , tectonic shifts , and even small changes in our orbit have all had observable effects on planetary warming and cooling patterns.

But climate records are able to show that today’s global warming—particularly what has occured since the start of the industrial revolution—is happening much, much faster than ever before. According to NASA , “[t]hese natural causes are still in play today, but their influence is too small or they occur too slowly to explain the rapid warming seen in recent decades.” And the records refute the misinformation that natural causes are the main culprits behind climate change, as some in the fossil fuel industry and conservative think tanks would like us to believe.

Chemical manufacturing plants emit fumes along Onondaga Lake in Solvay, New York, in the late-19th century. Over time, industrial development severely polluted the local area.

Library of Congress, Prints & Photographs Division, Detroit Publishing Company Collection

Scientists agree that human activity is the primary driver of what we’re seeing now worldwide. (This type of climate change is sometimes referred to as anthropogenic , which is just a way of saying “caused by human beings.”) The unchecked burning of fossil fuels over the past 150 years has drastically increased the presence of atmospheric greenhouse gases, most notably carbon dioxide . At the same time, logging and development have led to the widespread destruction of forests, wetlands, and other carbon sinks —natural resources that store carbon dioxide and prevent it from being released into the atmosphere.

Right now, atmospheric concentrations of greenhouse gases like carbon dioxide, methane , and nitrous oxide are the highest they’ve been in the last 800,000 years . Some greenhouse gases, like hydrochlorofluorocarbons (HFCs) , do not even exist in nature. By continuously pumping these gases into the air, we helped raise the earth’s average temperature by about 1.9 degrees Fahrenheit during the 20th century—which has brought us to our current era of deadly, and increasingly routine, weather extremes. And it’s important to note that while climate change affects everyone in some way, it doesn’t do so equally: All over the world, people of color and those living in economically disadvantaged or politically marginalized communities bear a much larger burden , despite the fact that these communities play a much smaller role in warming the planet.

Our ways of generating power for electricity, heat, and transportation, our built environment and industries, our ways of interacting with the land, and our consumption habits together serve as the primary drivers of climate change. While the percentages of greenhouse gases stemming from each source may fluctuate, the sources themselves remain relatively consistent.

Traffic on Interstate 25 in Denver

David Parsons/iStock

The cars, trucks, ships, and planes that we use to transport ourselves and our goods are a major source of global greenhouse gas emissions. (In the United States, they actually constitute the single-largest source.) Burning petroleum-based fuel in combustion engines releases massive amounts of carbon dioxide into the atmosphere. Passenger cars account for 41 percent of those emissions, with the typical passenger vehicle emitting about 4.6 metric tons of carbon dioxide per year. And trucks are by far the worst polluters on the road. They run almost constantly and largely burn diesel fuel, which is why, despite accounting for just 4 percent of U.S. vehicles, trucks emit 23 percent of all greenhouse gas emissions from transportation.

We can get these numbers down, but we need large-scale investments to get more zero-emission vehicles on the road and increase access to reliable public transit .

As of 2021, nearly 60 percent of the electricity used in the United States comes from the burning of coal, natural gas , and other fossil fuels . Because of the electricity sector’s historical investment in these dirty energy sources, it accounts for roughly a quarter of U.S. greenhouse gas emissions, including carbon dioxide, methane, and nitrous oxide.

That history is undergoing a major change, however: As renewable energy sources like wind and solar become cheaper and easier to develop, utilities are turning to them more frequently. The percentage of clean, renewable energy is growing every year—and with that growth comes a corresponding decrease in pollutants.

But while things are moving in the right direction, they’re not moving fast enough. If we’re to keep the earth’s average temperature from rising more than 1.5 degrees Celsius, which scientists say we must do in order to avoid the very worst impacts of climate change, we have to take every available opportunity to speed up the shift from fossil fuels to renewables in the electricity sector.

The factories and facilities that produce our goods are significant sources of greenhouse gases; in 2020, they were responsible for fully 24 percent of U.S. emissions. Most industrial emissions come from the production of a small set of carbon-intensive products, including basic chemicals, iron and steel, cement and concrete, aluminum, glass, and paper. To manufacture the building blocks of our infrastructure and the vast array of products demanded by consumers, producers must burn through massive amounts of energy. In addition, older facilities in need of efficiency upgrades frequently leak these gases, along with other harmful forms of air pollution .

One way to reduce the industrial sector’s carbon footprint is to increase efficiency through improved technology and stronger enforcement of pollution regulations. Another way is to rethink our attitudes toward consumption (particularly when it comes to plastics ), recycling , and reuse —so that we don’t need to be producing so many things in the first place. And, since major infrastructure projects rely heavily on industries like cement manufacturing (responsible for 7 percent of annual global greenhouse gas), policy mandates must leverage the government’s purchasing power to grow markets for cleaner alternatives, and ensure that state and federal agencies procure more sustainably produced materials for these projects. Hastening the switch from fossil fuels to renewables will also go a long way toward cleaning up this energy-intensive sector.

The advent of modern, industrialized agriculture has significantly altered the vital but delicate relationship between soil and the climate—so much so that agriculture accounted for 11 percent of U.S. greenhouse gas emissions in 2020. This sector is especially notorious for giving off large amounts of nitrous oxide and methane, powerful gases that are highly effective at trapping heat. The widespread adoption of chemical fertilizers , combined with certain crop-management practices that prioritize high yields over soil health, means that agriculture accounts for nearly three-quarters of the nitrous oxide found in our atmosphere. Meanwhile, large-scale industrialized livestock production continues to be a significant source of atmospheric methane, which is emitted as a function of the digestive processes of cattle and other ruminants.

Stephen McComber holds a squash harvested from the community garden in Kahnawà:ke Mohawk Territory, a First Nations reserve of the Mohawks of Kahnawà:ke, in Quebec.

Stephanie Foden for NRDC

But farmers and ranchers—especially Indigenous farmers, who have been tending the land according to sustainable principles —are reminding us that there’s more than one way to feed the world. By adopting the philosophies and methods associated with regenerative agriculture , we can slash emissions from this sector while boosting our soil’s capacity for sequestering carbon from the atmosphere, and producing healthier foods.

A decades-old, plugged and abandoned oil well at a cattle ranch in Crane County, Texas, in June 2021, when it was found to be leaking brine water

Matthew Busch/Bloomberg via Getty Images

Oil and gas lead to emissions at every stage of their production and consumption—not only when they’re burned as fuel, but just as soon as we drill a hole in the ground to begin extracting them. Fossil fuel development is a major source of methane, which invariably leaks from oil and gas operations : drilling, fracking , transporting, and refining. And while methane isn’t as prevalent a greenhouse gas as carbon dioxide, it’s many times more potent at trapping heat during the first 20 years of its release into the atmosphere. Even abandoned and inoperative wells—sometimes known as “orphaned” wells —leak methane. More than 3 million of these old, defunct wells are spread across the country and were responsible for emitting more than 280,000 metric tons of methane in 2018.

Unsurprisingly, given how much time we spend inside of them, our buildings—both residential and commercial—emit a lot of greenhouse gases. Heating, cooling, cooking, running appliances, and maintaining other building-wide systems accounted for 13 percent of U.S. emissions overall in 2020. And even worse, some 30 percent of the energy used in U.S. buildings goes to waste, on average.

Every day, great strides are being made in energy efficiency , allowing us to achieve the same (or even better) results with less energy expended. By requiring all new buildings to employ the highest efficiency standards—and by retrofitting existing buildings with the most up-to-date technologies—we’ll reduce emissions in this sector while simultaneously making it easier and cheaper for people in all communities to heat, cool, and power their homes: a top goal of the environmental justice movement.

An aerial view of clearcut sections of boreal forest near Dryden in Northwestern Ontario, Canada, in June 2019

River Jordan for NRDC

Another way we’re injecting more greenhouse gas into the atmosphere is through the clearcutting of the world’s forests and the degradation of its wetlands . Vegetation and soil store carbon by keeping it at ground level or underground. Through logging and other forms of development, we’re cutting down or digging up vegetative biomass and releasing all of its stored carbon into the air. In Canada’s boreal forest alone, clearcutting is responsible for releasing more than 25 million metric tons of carbon dioxide into the atmosphere each year—the emissions equivalent of 5.5 million vehicles.

Government policies that emphasize sustainable practices, combined with shifts in consumer behavior , are needed to offset this dynamic and restore the planet’s carbon sinks .

The Yellow Line Metro train crossing over the Potomac River from Washington, DC, to Virginia on June 24, 2022

Sarah Baker

The decisions we make every day as individuals—which products we purchase, how much electricity we consume, how we get around, what we eat (and what we don’t—food waste makes up 4 percent of total U.S. greenhouse gas emissions)—add up to our single, unique carbon footprints . Put all of them together and you end up with humanity’s collective carbon footprint. The first step in reducing it is for us to acknowledge the uneven distribution of climate change’s causes and effects, and for those who bear the greatest responsibility for global greenhouse gas emissions to slash them without bringing further harm to those who are least responsible .

The big, climate-affecting decisions made by utilities, industries, and governments are shaped, in the end, by us : our needs, our demands, our priorities. Winning the fight against climate change will require us to rethink those needs, ramp up those demands , and reset those priorities. Short-term thinking of the sort that enriches corporations must give way to long-term planning that strengthens communities and secures the health and safety of all people. And our definition of climate advocacy must go beyond slogans and move, swiftly, into the realm of collective action—fueled by righteous anger, perhaps, but guided by faith in science and in our ability to change the world for the better.

If our activity has brought us to this dangerous point in human history, breaking old patterns can help us find a way out.

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Climate Change: Evidence and Causes: Update 2020 (2020)

Chapter: conclusion, c onclusion.

This document explains that there are well-understood physical mechanisms by which changes in the amounts of greenhouse gases cause climate changes. It discusses the evidence that the concentrations of these gases in the atmosphere have increased and are still increasing rapidly, that climate change is occurring, and that most of the recent change is almost certainly due to emissions of greenhouse gases caused by human activities. Further climate change is inevitable; if emissions of greenhouse gases continue unabated, future changes will substantially exceed those that have occurred so far. There remains a range of estimates of the magnitude and regional expression of future change, but increases in the extremes of climate that can adversely affect natural ecosystems and human activities and infrastructure are expected.

Citizens and governments can choose among several options (or a mixture of those options) in response to this information: they can change their pattern of energy production and usage in order to limit emissions of greenhouse gases and hence the magnitude of climate changes; they can wait for changes to occur and accept the losses, damage, and suffering that arise; they can adapt to actual and expected changes as much as possible; or they can seek as yet unproven “geoengineering” solutions to counteract some of the climate changes that would otherwise occur. Each of these options has risks, attractions and costs, and what is actually done may be a mixture of these different options. Different nations and communities will vary in their vulnerability and their capacity to adapt. There is an important debate to be had about choices among these options, to decide what is best for each group or nation, and most importantly for the global population as a whole. The options have to be discussed at a global scale because in many cases those communities that are most vulnerable control few of the emissions, either past or future. Our description of the science of climate change, with both its facts and its uncertainties, is offered as a basis to inform that policy debate.

A CKNOWLEDGEMENTS

The following individuals served as the primary writing team for the 2014 and 2020 editions of this document:

• Eric Wolff FRS, (UK lead), University of Cambridge
• Inez Fung (NAS, US lead), University of California, Berkeley
• Brian Hoskins FRS, Grantham Institute for Climate Change
• John F.B. Mitchell FRS, UK Met Office
• Tim Palmer FRS, University of Oxford
• Benjamin Santer (NAS), Lawrence Livermore National Laboratory
• John Shepherd FRS, University of Southampton
• Keith Shine FRS, University of Reading.
• Susan Solomon (NAS), Massachusetts Institute of Technology
• Kevin Trenberth, National Center for Atmospheric Research
• John Walsh, University of Alaska, Fairbanks
• Don Wuebbles, University of Illinois

Staff support for the 2020 revision was provided by Richard Walker, Amanda Purcell, Nancy Huddleston, and Michael Hudson. We offer special thanks to Rebecca Lindsey and NOAA Climate.gov for providing data and figure updates.

The following individuals served as reviewers of the 2014 document in accordance with procedures approved by the Royal Society and the National Academy of Sciences:

• Richard Alley (NAS), Department of Geosciences, Pennsylvania State University
• Alec Broers FRS, Former President of the Royal Academy of Engineering
• Harry Elderfield FRS, Department of Earth Sciences, University of Cambridge
• Joanna Haigh FRS, Professor of Atmospheric Physics, Imperial College London
• Isaac Held (NAS), NOAA Geophysical Fluid Dynamics Laboratory
• John Kutzbach (NAS), Center for Climatic Research, University of Wisconsin
• Jerry Meehl, Senior Scientist, National Center for Atmospheric Research
• John Pendry FRS, Imperial College London
• John Pyle FRS, Department of Chemistry, University of Cambridge
• Gavin Schmidt, NASA Goddard Space Flight Center
• Emily Shuckburgh, British Antarctic Survey
• Gabrielle Walker, Journalist
• Andrew Watson FRS, University of East Anglia

The Support for the 2014 Edition was provided by NAS Endowment Funds. We offer sincere thanks to the Ralph J. and Carol M. Cicerone Endowment for NAS Missions for supporting the production of this 2020 Edition.

F OR FURTHER READING

For more detailed discussion of the topics addressed in this document (including references to the underlying original research), see:

• Intergovernmental Panel on Climate Change (IPCC), 2019: Special Report on the Ocean and Cryosphere in a Changing Climate [ https://www.ipcc.ch/srocc ]
• National Academies of Sciences, Engineering, and Medicine (NASEM), 2019: Negative Emissions Technologies and Reliable Sequestration: A Research Agenda [ https://www.nap.edu/catalog/25259 ]
• Royal Society, 2018: Greenhouse gas removal [ https://raeng.org.uk/greenhousegasremoval ]
• U.S. Global Change Research Program (USGCRP), 2018: Fourth National Climate Assessment Volume II: Impacts, Risks, and Adaptation in the United States [ https://nca2018.globalchange.gov ]
• IPCC, 2018: Global Warming of 1.5°C [ https://www.ipcc.ch/sr15 ]
• USGCRP, 2017: Fourth National Climate Assessment Volume I: Climate Science Special Reports [ https://science2017.globalchange.gov ]
• NASEM, 2016: Attribution of Extreme Weather Events in the Context of Climate Change [ https://www.nap.edu/catalog/21852 ]
• IPCC, 2013: Fifth Assessment Report (AR5) Working Group 1. Climate Change 2013: The Physical Science Basis [ https://www.ipcc.ch/report/ar5/wg1 ]
• NRC, 2013: Abrupt Impacts of Climate Change: Anticipating Surprises [ https://www.nap.edu/catalog/18373 ]
• NRC, 2011: Climate Stabilization Targets: Emissions, Concentrations, and Impacts Over Decades to Millennia [ https://www.nap.edu/catalog/12877 ]
• Royal Society 2010: Climate Change: A Summary of the Science [ https://royalsociety.org/topics-policy/publications/2010/climate-change-summary-science ]
• NRC, 2010: America’s Climate Choices: Advancing the Science of Climate Change [ https://www.nap.edu/catalog/12782 ]

Much of the original data underlying the scientific findings discussed here are available at:

• https://data.ucar.edu/
• https://climatedataguide.ucar.edu
• https://iridl.ldeo.columbia.edu
• https://ess-dive.lbl.gov/
• https://www.ncdc.noaa.gov/
• https://www.esrl.noaa.gov/gmd/ccgg/trends/
• http://scrippsco2.ucsd.edu
• http://hahana.soest.hawaii.edu/hot/

Climate change is one of the defining issues of our time. It is now more certain than ever, based on many lines of evidence, that humans are changing Earth's climate. The Royal Society and the US National Academy of Sciences, with their similar missions to promote the use of science to benefit society and to inform critical policy debates, produced the original Climate Change: Evidence and Causes in 2014. It was written and reviewed by a UK-US team of leading climate scientists. This new edition, prepared by the same author team, has been updated with the most recent climate data and scientific analyses, all of which reinforce our understanding of human-caused climate change.

Scientific information is a vital component for society to make informed decisions about how to reduce the magnitude of climate change and how to adapt to its impacts. This booklet serves as a key reference document for decision makers, policy makers, educators, and others seeking authoritative answers about the current state of climate-change science.

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How Climate Change Impacts Water Access

The water cycle is part of our everyday lives, but climate change may have dire consequences for everyday water access.

Biology, Health, Conservation, Earth Science

Herder Collecting Water

Climate change is already hurting water access for people around the world. Here, a Samburu herder collects water for his flock in Sahara Conservancy, Kenya.

Photograph from the National Geographic image collection

Climate change is already affecting water access for people around the world, causing more severe droughts and floods. Increasing global temperatures are one of the main contributors to this problem. Climate change impacts the water cycle by influencing when, where, and how much precipitation falls. It also leads to more severe weather events over time. Increasing global temperatures cause water to evaporate in larger amounts, which will lead to higher levels of atmospheric water vapor and more frequent, heavy, and intense rains in the coming years.

Climate scientists predict that this shift will lead to more floods since more water will fall than vegetation and soil can absorb. The remaining water, or runoff , drains into nearby waterways, picking up contaminants like fertilizer on the way. Excess runoff eventually travels to larger bodies of water like lakes, estuaries, and the ocean, polluting the water supply and limiting water access for humans and ecosystems .

When fertilizers from farming wash into lakes and the ocean, they promote the rapid growth of algae. These resulting algal blooms clog coasts and waterways with clouds of green, blue-green, red, or brown algae. The blooms block sunlight from reaching underwater life and diminish oxygen levels within the water. Toxins from the blooms can kill off fish and other aquatic animals, make people sick, and even kill humans. These toxins are especially dangerous because they can survive purification processes, making tap water unfit to consume once contaminated. Algal blooms also impact industries that rely on the water for business, and often cause local waterfronts to shut down during blooms. As the climate warms, harmful algal blooms happen more often and become more severe.

As the ocean warms, freshwater glaciers around Earth begin to melt at an unsustainable rate, which results in rising sea levels. The freshwater from the melted glaciers eventually runs into the ocean. With the rising of sea levels, salt water can more easily contaminate underground freshwater-bearing rocks, called aquifers. A process called desalination removes salt from salt water, but it is a last-resort, energy-intensive, costly process for places where there are persistent droughts and freshwater is lacking. The Middle East, North Africa, and the Caribbean use desalination to produce freshwater out of necessity.

In the Northern Hemisphere—where snow, a freshwater source, typically accumulates—warmer temperatures mean less snowfall, which leaves less water available in local reservoirs after winter. This negatively impacts farmers, who are left without enough water to irrigate their crops in the growing season.

There are many things that everyone can do to lessen the impact of climate change . Some measures include growing your own fruits and vegetables or buying locally grown produce, since produce is often transported to grocery stores from far away by trucks, which add more carbon dioxide to the atmosphere . You could also walk or ride a bike instead of driving a car. On a larger scale, industries that are dependent on fossil fuels need to make the switch to renewable, cleaner energy sources to influence our planet for the better.

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Yale Climate Connections

Climate change is affecting mental health literally everywhere

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Farmers who can’t sleep, worrying they’ll lose everything amid increasing drought. Youth struggling with depression over a future that feels hopeless. Indigenous people grief-stricken over devastated ecosystems. For all these people and more, climate change is taking a clear toll on mental health — in every part of the world.  

Experts shared these examples and others during a recent summit organized by the Connecting Climate Minds network that brought together hundreds of scientists, doctors, community leaders, and other experts from dozens of countries who have spent the past year studying how climate change is harming mental health in their regions. 

Although mental illnesses are often viewed as an individual problem, the experts made clear that climate change is contributing to mental health challenges everywhere. 

The Connecting Climate Minds youth ambassador from Borneo, Jhonatan Yuditya Pratama, said his Indigenous community views nature as a sacred extension of being. Seeing the devastation of climate change on ancestral lands has brought his community “a profound sense of grief and loss,” he said.

“For us, mental health isn’t just about individuals,” he said. “It’s about the collective well-being of our communities and the land itself. When nature suffers, so do we.”  

Extreme weather and air pollution are taking a toll 

In her keynote, Marina Romanello, executive director of the Lancet Countdown and a Connecting Climate Minds advisory board member, explained the key ways that climate change threatens mental health. 

• Extreme heat is associated with increased self-harm and violence as well as more general feelings of negativity. It also leads to feelings of isolation when people feel trapped inside their relatively cooler homes.
• Wildfire or extreme weather stokes anxiety leading up to an event — and afterward — that can lead to PTSD or depression for survivors who have seen cherished places or lives lost.
• Farmers, fisherpeople, and others whose livelihoods are tied to the environment experience chronic stress, worry, and depression over things they can’t control, like extreme weather, habitat loss, and drought.
• Water scarcity increases stress for people in charge of seeking and transporting household water. Water scarcity also makes it hard for people to stay clean, potentially leading to isolation, loneliness, and depression. 
• Air pollution can keep kids out of school, leading to social isolation and, over time, a sense of hopelessness about the future. 

What’s more, people are experiencing the compounding effects of multiple disasters, said Emma Lawrance, who leads the Climate Cares Centre, a U.K.-based team that researches and supports mental health in the face of environmental crises: “With more frequent disasters, people can no longer recover psychologically from one before another occurs,” Lawrance said.  

And these escalating hazards are exacerbating social inequality, said Alaa Abelgawad, the Connecting Climate Minds youth ambassador representing northern Africa and western Asia. “[It’s] manifesting as anxiety, depression, and a profound sense of disempowerment among marginalized populations.”

Who is most vulnerable to climate change and mental health challenges? 

Many Indigenous communities have already been facing intergenerational trauma and a sense of deep disconnect from land and culture. Recurring climate devastation can intensify feelings of grief, stress, and disillusionment about the future, contributing to increased rates of addiction and suicide, participants said. 

Farmers, too, are among the most vulnerable. Changing seasonal norms, increasing drought, and a higher risk of severe weather are directly affecting their livelihoods. 

Sacha Wright, head of research at the youth-focused organization Force of Nature and part of Connecting Climate Minds’s “lived experience” working group, said that in Kenya, many small farmers are struggling with declining harvests and out of desperation have resorted to cutting down trees for charcoal. Though they felt they had no choice, some said cutting down the trees made the whole situation feel even worse. She spoke of high rates of depression, hopelessness, trauma, and a widespread feeling of “not knowing what to do.” 

For young people, climate change can also evoke a sense of hopelessness and powerlessness. In the Yucatan, one young person Wright interviewed said the only choices in life there are to migrate or enter the military. 

“When I see drought, I see my community leaving school and going to the military,” the person interviewed said. 

Mercy Njeru, a member of Connecting Climate Mind’s sub-Saharan Africa working group, said extreme heat is often leading to school closures across the region, setting youth up for failure and a sense of hopelessness. 

“When it’s so hot and you’re so anxious you can’t work, you can’t do anything because you’re feeling anxious or you’re feeling so sad from all the heat around you,” she said. 

In addition to environmental impacts, generational inequity and a sense of moral distress also contribute to anxiety for many youth. Britt Wray, director of Stanford Medicine’s Special Initiative on Climate Change and Mental Health, said she hears from many young people that power holders aren’t taking sufficient action, instead depending entirely on their generation to solve climate change. 

“This offloading of responsibility — without adequate partnership from the elder and more powerful contingents among us — can make burdensome climate anxiety and distress much worse,” she said.

Read: What baby boomers can do about climate change, according to Bill McKibben

What can be done to protect mental health as the climate changes? 

To help address the rising tide of mental health challenges, governments and public health leaders need to know exactly what kinds of impacts people are experiencing in their own communities.

First step: looking at experiences in every region. 

“We will only be successful if we can continue to connect and engage people from very different sectors, from neighborhoods all the way to multilateral organizations,” said Pamela Collins, chair of the department of mental health at the Johns Hopkins Bloomberg School of Public Health. 

Other examples of ways forward include everything from expanding health insurance to include climate-related mental health impacts to ensuring government policy supports people whose work has been affected by climate change to improve their job prospects. Several participants also spoke of the importance of returning to the wisdom of ancestral knowledge to address climate change in general, including mental health impacts. 

Other specific solutions offered by Connecting Climate Minds participants include:

• More public green space. Collins, the Hopkins professor, cited a study highlighting the need for more accessible green space in cities, a move that could have multiple positive outcomes, including on mental health. Forest bathing , AKA spending dedicated time in nature, reduces stress and anxiety, increases serotonin production, and improves mood regulation and overall mental health — all while being low-intensity and low-cost, said Niaya Harper Igarashi, part of Connecting Climate Mind’s eastern and southeastern Asia working group. 
• Focusing on reducing inequity. Making sure everyone has access to nutritious food, clean air and water, and sustainable energy sources is good for the climate and community. 
• Talking helps. In many communities, mental health is a taboo topic. By talking more openly about it on a personal level, in social or spiritual settings, at the dinner table, or in your doctor’s office, individuals can combat stigma and contribute to a growing understanding of these issues. 
• Meeting people where they are. From using vocabulary that makes sense for different communities to meeting people’s basic needs, solutions are most effective when they’re tailored for what real people are actually going through. For example, Wray, the Stanford expert, said meeting kids where they are includes screening for climate distress where many of them are every day: at school.

Lawrance, the Climate Cares lead who helped organize the summit, said it was heartening to see solutions being advanced around the world. 

“The dialogue showed this really strongly: that many solutions do already exist,” she said. “And it’s by learning from each other’s ways of knowing and doing that we can best find the ones that work for our context, and ensure people experiencing the worst climate impacts have a future where they cannot just survive, but thrive.”

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How is climate change impacting the world’s ocean

The ocean has long taken the brunt of the impacts of human-made global warming, says UN Climate Change . As the planet’s greatest carbon sink, the ocean absorbs excess heat and energy released from rising greenhouse gas emissions trapped in the Earth’s system. Today, the ocean has absorbed about 90 percent of the heat generated by rising emissions. 

As the excessive heat and energy warms the ocean, the change in temperature leads to unparalleled cascading effects, including ice-melting, sea-level rise, marine heatwaves, and ocean acidification. 

These changes ultimately cause a lasting impact on marine biodiversity, and the lives and livelihoods of coastal communities and beyond - including around 680 million people living in low-lying coastal areas, almost 2 billion who live in half of the world’s megacities that are coastal, nearly half of the world’s population (3.3 billion) that depends on fish for protein, and almost 60 million people who work in fisheries and the aquaculture sector worldwide. 

Here are some of the major consequences of the impacts of climate change on the ocean.

Sea-level rise

Sea-level rise has accelerated in recent decades due to increasing ice loss in the world’s polar regions. Latest data from the World Meteorological Organization shows that global mean sea-level reached a new record high in 2021, rising an average of 4.5 millimeter per year over the period 2013 to 2021. 

Together with intensifying tropical cyclones, sea-level rise has exacerbated extreme events such as deadly storm surges and coastal hazards such as flooding, erosion and landslides, which are now projected to occur at least once a year in many locations. Such events occurred once per century historically.

Moreover, the Intergovernmental Panel on Climate Change (IPCC) says that several regions, such as the western Tropical Pacific, the South-west Pacific, the North Pacific, the South-west Indian Ocean and the South Atlantic, face substantially faster sea-level rise.  

Marine heatwaves

Marine heatwaves have doubled in frequency, and have become longer-lasting, more intense and extensive. The IPCC says that human influence has been the main driver of the ocean heat increase observed since the 1970s. 

The majority of heatwaves took place between 2006 and 2015, causing widespread coral bleaching and reef degradation. In 2021, nearly 60 percent of the world’s ocean surface experienced at least one spell of marine heatwaves. The UN Environment Programme says that every one of the world’s coral reefs could bleach by the end of the century if the water continues to warm. 

Coral bleaching occurs as reefs lose their life-sustaining microscopic algae when under stress. The last global bleaching event started in 2014 and extended well into 2017 - spreading across the Pacific, Indian and Atlantic oceans.   

Loss of marine biodiversity

Rising temperatures increase the risk of irreversible loss of marine and coastal ecosystems . Today, widespread changes have been observed, including damage to coral reefs and mangroves that support ocean life, and migration of species to higher latitudes and altitudes where the water could be cooler.  Latest estimates from the UN Educational, Scientific and Cultural Organization warn that more than half of the world’s marine species may stand on the brink of extinction by 2100. At a 1.1°C  increase in temperature today, an estimated 60 percent of the world's marine ecosystems have already been degraded or are being used unsustainably. A warming of 1.5°C threatens to destroy 70 to 90 percent of coral reefs , and a 2°C increase means a nearly 100 percent loss - a point of no return.

The ocean – the world’s greatest ally against climate change

The ocean is central to reducing global greenhouse gas emissions. Here are a few reasons we need to safeguard the ocean as our best ally for climate solutions.

Peter Thomson: Moving the needle on the sustainable blue economy

Ambassador Peter Thomson of Fiji, UN Special Envoy for the Ocean, mobilizes global action to conserve and sustainably use the ocean. Read the full interview.

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Climate change is a human rights issue

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In April, the European Court of Human Rights ruled in favour of a group of seniors who alleged that the Swiss government’s failure to meet climate change mitigation targets is having an adverse impact on their health, well-being and quality of life.

This landmark decision by the highest human rights court in Europe confirms not only that climate change is intimately linked to human rights, but effectively holds all European governments accountable to adopt more rigorous measures to combat climate change.

Clear obligations

It is well documented that runaway carbon dioxide emissions, deforestation, resource depletion and the acidification of the oceans have contributed to increased heatwaves and megadroughts , more frequent and violent storms and unseasonable precipitation .

Unpredictable weather patterns and swings in temperature disrupt ecosystems, wildlife and threaten agriculture and food production .

Simply put, climate change poses clear threats to human life by exacerbating “existing medical conditions such as cardiovascular, respiratory and kidney conditions or mental illnesses and stress.”

The 1994 United Nations Framework Convention on Climate Change is a global commitment to stabilize greenhouse gas emissions so as to stem dangerous anthropogenic effects on the world’s climate.

The 2015 Paris Agreement commits governments to limit global warming to 2 C above pre-industrial levels through progressively ambitious climate action plans . However, by 2030 the world may be faced with a temperature rise of close to 3 C as countries are still not doing enough to cut carbon emissions.

According to the independent Climate Action Tracker , the vast majority of countries are insufficiently living up to their global commitments.

Global inaction has scientists around the world feeling “hopeless and broken” and “scared” as governments fail to act despite clear scientific evidence that climate change will have catastrophic consequences.

Read more: COP28: Why we need to break our addiction to combustion

The Climate Action Tracker has rated Canada’s efforts as “highly insufficient” and inconsistent with Paris commitments citing its state-sanctioned expansion of pipelines , lackluster climate target and ineffective policies and climate finance.

Taking legal action

The United Nations High Commissioner for Human Rights has long underlined that climate change threatens a variety of human rights , including the right to life, food, health, housing, culture and development. In particular, marginalized populations — including children, girls and women, migrants, people with disabilities and Indigenous peoples — are disproportionately impacted by climate change .

In the face of government inaction on climate change, there has been a rise in climate litigation .

In the landmark Urgenda case , the Supreme Court of the Netherlands affirmed there is an obligation to take more effective action to prevent dangerous climate change to protect the life and well-being of all citizens , including those not yet born.

Children across the globe have also been taking legal action against governments .

A case in Canada filed by children and youths alleged that climate inaction will expose them and future generations to physical and psychological harm in violation of several sections of the Canadian Charter of Rights and Freedoms. While the case eventually failed, it also set an important example .

At the international level, Colombia and Chile have requested the Inter-American Court of Human Rights to clarify obligations under the frame of international human rights law with regard to the climate crisis. Meanwhile, several island states ( including Vanuatu ) have requested both the International Tribunal for the Law of the Sea and the International Court of Justice to elaborate on the obligations of States to ensure the protection of the climate system for present and future generations.

While these actions may seem small in the face of the crisis, they all present enormous opportunities to correct inaction and set new global precedent.

Continuing challenges

Climate change is one of the defining challenges of our time.

If unaddressed, climate change will cause untold ecological disaster and human suffering — and even threaten international peace and security . The consequences of warmer oceans and uncontrolled gaseous emissions transcend borders, ethnicities and political divides to affect all.

The recent European decision is one of a number of climate change cases that are currently ongoing . Though climate litigation can be costly and time-consuming , such cases underline the powerful role that individuals, young and old alike, can play to hold decision-makers to account and prompt greater action on climate change.

Read more: Australia can have a future for the gas industry, or meet its climate commitments – but not both

Governments must be reminded that they shoulder the twin responsibilities to both fulfil environmental commitments and to protect human health and human rights . In light of the pressing climate crisis and countdown to 2030, concrete action and change cannot come soon enough.

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The green IT revolution: A blueprint for CIOs to combat climate change

Companies and governments looking to combat climate change are turning to tech for help. AI, new technologies, and some promising tech-driven business models have raised hopes for dramatic progress.

About the authors

This article is a collaborative effort by Gerrit Becker, Luca Bennici, Anamika Bhargava, Andrea Del Miglio , Jeffrey Lewis , and Pankaj Sachdeva, representing views from McKinsey Technology.

While many organizations’ climate goals are lofty, enterprise technology leaders—CIOs, chief digital innovation officers (CDIOs), and chief technology officers (CTOs), among others—have not always succeeded at turning climate ambitions into reality. One of the biggest reasons is that hard facts and clear paths of action are scarce. Misconceptions and misinformation have clouded the picture of what CIOs and tech leaders should do.

We have done extensive analysis of where technology can have the biggest impact on reducing emissions. To start, we divided technology’s role into two primary types of activities:

• offense—the use of technology and analytics to cut emissions by reducing (improving operational efficiency), replacing (shifting emission-generating activities to cleaner alternatives), and reusing (recycling material)
• defense—the actions IT can take to reduce emissions from the enterprise’s technology estate

Scope of the McKinsey analysis

McKinsey’s emissions analysis for this report focuses on enterprise technology emissions, which are the business IT emissions from the hardware, software, IT services, enterprise communications equipment, mobile devices, fixed and mobile network services, and internal technology teams that a company uses for its own operations and that a CIO has control over. These include the emissions related to the full life cycles of the products and services that an enterprise IT function uses, including their development, delivery, usage, and end of life (exhibit). Our internal services emissions' analysis assumes around 40 percent of IT workers are working from home.

The analysis does not include the emissions from the technology products and services that a company is selling (such as data center capacity sold by hyperscalers), operational technology devices (such as sensors and point-of-sale systems), and cryptocurrency mining.

The defense activities are where the CIO, as the head of IT, can act independently and quickly. This article focuses on defense, specifically the IT elements over which a CIO has direct control. We examined emissions from use of electricity for owned enterprise IT operations, such as the running of on-premises data centers and devices (classified as scope 2 by the Greenhouse Gas Protocol 1 Greenhouse Gas Protocol: Technical Guidance for Calculating Scope 3 Emissions: Supplement to the Corporate Value Chain (Scope 3) Accounting & Reporting Standard , World Resources Institute & World Business Council for Sustainable Development, 2013. Scope 1 emissions are direct emissions from the activities of an organization or under their control, including fuel combustion on site such as gas boilers, fleet vehicles, and air-conditioning leaks; scope 2 emissions are from electricity purchased and used by the organization; and scope 3 emissions are all indirect emissions not included in scope 2 that occur in the value chain of the reporting company, including both upstream and downstream emissions. ), and indirect emissions from technology devices that the CIO buys and disposes of (scope 3). 2 These calculations do not include emissions from technology-driven services sold, such as cloud capacity. (See sidebar, “Scope of the McKinsey analysis.”)

What the facts say

Our analysis has uncovered several facts that contravene some commonly held views about enterprise technology emissions. These facts involve the significant amount of tech-related emissions, the share of emissions from end-user devices, the variety of mitigation options available, and the favorable impact of shifting to cloud computing.

Enterprise technology generates significant emissions

Enterprise technology is responsible for emitting about 350 to 400 megatons of carbon dioxide equivalent gases (CO 2 e), accounting for about 1 percent of total global greenhouse gas (GHG) emissions. At first blush, this might not seem like a lot, but it equals about half of the emissions from aviation or shipping and is the equivalent of the total carbon emitted by the United Kingdom.

The industry sector that contributes the largest share of technology-related scope 2 and scope 3 GHG emissions is communications, media, and services (Exhibit 1). Enterprise technology’s contribution to total emissions is especially high for insurance (45 percent of total scope 2 emissions) and for banking and investment services (36 percent).

This amount of carbon dioxide and equivalent gases is a significant prize for companies under increasing pressure to cut emissions. Progress on climate change requires action on many fronts, and enterprise technology offers an important option that CIOs and companies can act on quickly.

You’re invited

To a McKinsey Technology webinar on the critical role of technology in building a sustainable enterprise on October 25, 9:30–10:30am ET.

The biggest carbon culprit is end-user devices, not on-premises data centers

End-user devices—laptops, tablets, smartphones, and printers—generate 1.5 to 2.0 times more carbon globally than data centers (Exhibit 2). 3 On-premises and co-located data centers used by enterprises, not including data center capacity sold by hyperscalers. One reason is that companies have significantly more end-user devices than servers in on-premises data centers. In addition, the devices typically are replaced much more often: smartphones have an average refresh cycle of two years, laptops four years, and printers five years. On average, servers are replaced every five years, though 19 percent of organizations wait longer. 4 Rhona Ascierto and Andy Lawrence, Uptime Institute global data center survey 2020 , Uptime Institute, July 2020.

More worrisome, emissions from end-user devices are on track to increase at a CAGR of 12.8 percent per year. 5 End-user computing market: Growth, trends, COVID-19 impact, and forecasts (2022–2027) , Mordor Intelligence, January 2022. Efforts to address this could target the major causes of emissions from these devices. About three-fourths of the emissions comes from manufacturing, upstream transportation, and disposal. A significant source of these emissions is the semiconductors that power the devices.

Plenty of low-cost/high-impact options exist, starting with improved sourcing

We have found that when it comes to going green, many CIOs think in terms of investments needed to replace items or upgrade facilities. Our analysis, however, finds that CIOs can capture significant carbon benefits without making a significant investment—and in some cases can even save money (Exhibit 3).

Overall, for example, 50 to 60 percent of emissions related to end-user devices can be addressed through sourcing changes, primarily by procuring fewer devices per person and extending the life cycle of each device through recycling. These options will not require any investment and will lower costs, though companies may want to evaluate the impact on employee experience.

In addition, companies can more aggressively recycle their devices; 89 percent of organizations recycle less than 10 percent of their hardware overall. 6 Sustainable IT: Why it’s time for a green revolution for your organization’s IT , Capgemini Research Institute, 2021. CIOs can put pressure on suppliers to use greener devices, especially as companies in the semiconductor sector are already increasing their commitments to emission reduction. Further low-cost, high-impact actions include optimizing business travel and data center computing needs, as well as increasing the use of cloud to manage workloads.

Moving to cloud has more impact than optimizing data centers

Optimizing an on-premises data center’s power usage effectiveness (PUE) 7 PUE describes how efficiently a computer data center uses energy, expressed as the ratio of total facility energy to IT equipment energy. is expensive and results in limited carbon abatement. If a company were to double what it spends on infrastructure and cloud to reduce PUE, it would cut carbon emissions by only 15 to 20 percent. Structural improvements in data centers and optimized layout can help, but the impact is limited, and many companies have already implemented them. More aggressive measures, such as moving data centers to cooler locations or investing in new cooling tech, are prohibitively expensive.

A more effective approach is to migrate workloads to the cloud. Hyperscalers (also known as cloud service providers) and co-locators are investing significantly to become greener through measures such as buying green energy themselves and investing in ultra-efficient data centers with a PUE equal to or less than 1.10, compared with the average PUE of 1.57 for an on-premises data center. 8 “Uptime Institute 11th annual Global Data Center Survey shows sustainability, outage, and efficiency challenges amid capacity growth,” Uptime Institute, September 14, 2021. (We estimate that companies could achieve just a 1.3 PUE score for their data center if they invested nearly 250 percent more, on average, over what they currently spend for their data centers and cloud presence.)

With thoughtful migration to and optimized usage of the cloud, companies could reduce the carbon emissions from their data centers by more than 55 percent—about 40 megatons of CO 2 e worldwide, the equivalent of the total carbon emissions from Switzerland.

Three steps to take now

With companies and governments under intensifying pressure to cut carbon emissions and with technology playing a key role in delivering on those goals, CIOs will find themselves on the front lines. The challenge will be to reduce IT’s carbon footprint while delivering high-quality, low-cost technology services to customers and employees.

On average, completion of the defensive steps might take three to four years. However, CIOs who act decisively and precisely can achieve 15 to 20 percent of carbon reduction potential in the first year with minimal investment.

CIOs can choose from among a wide array responses, particularly in conjunction with the CEO and the board. However, three measures they can take right now will prepare the organization for longer-term efforts. These measures involve sourcing strategies, key metrics, and a performance management system.

The net-zero transition: What it would cost, what it could bring

Move now on sourcing strategies.

Far and away the fastest and most effective defensive measure for reducing IT carbon emissions is to revise policies for technology sourcing. Optimizing the number of devices in line with standards followed by companies in the top quartile 9 Top quartile in terms of the ratio of devices to people is derived from the number of devices per person. Our analysis uses McKinsey Digital’s Ignite solutions and 2020 data. would reduce about 30 percent of end-user-device emissions, the amount of carbon emitted by Hong Kong. For example, top-quartile companies have one printer for every 16 people in the workplace; the overall average is one printer per eight people.

This sourcing shift does not necessarily lead to a degradation in user experience, because the rollout of 5G and increasingly advanced processing and compute power allow the main processing function to happen at the server. Therefore, devices can be less powerful and consume much less energy. Essentially, this is a software-as-a-service (SaaS) model where high-end and user-friendly experiences happen on the server, not the device. The effectiveness of this approach will depend on having stable networks, less resource-intensive coding at the device level, edge computing capabilities, and shifts of offerings to more efficient platforms (for example, cloud).

As part of this effort, the CIO and the business’s head of procurement will need to collaborate on reviewing and adjusting device refresh timelines and device-to-person ratios, as well as adjusting the basis for purchasing decisions. Procurement generally relies on cost/benefit calculations, and rightly so. That approach will need to expand to account for carbon dioxide emissions. The spirit of collaboration should extend to suppliers as well, with the parties working together to formulate plans that provide the greatest benefits for all.

A more thoughtful sourcing strategy extends beyond end-user devices. CIOs, for example, should look for green sources of the electricity IT uses. When these sources are unavailable, CIOs can direct procurement to power purchase agreements to offset carbon use. CIOs can also set green standards for their vendors and suppliers, requiring GHG emissions disclosures and incorporating them into their criteria for purchase decisions.

Establish a green ROI metric for technology costs

Any real progress on green technology can happen only when companies measure their “green returns.” But today, most green metrics omit cost and savings, which ultimately makes them impractical. A better metric focuses on cost per ton of carbon saved (accounting for costs saved as well). Sophisticated models calculate emissions throughout the full life cycle, including production, transportation, and disposal.

CIOs can further assess suppliers, manufacturers, and service providers based on how advanced they are in recycling and refurbishing electronics; designing circular components; extending product life cycles with better design, higher-quality manufacturing, and more robust materials; offering repair services; and reselling to consumers.

Decisions about IT spending need to consider a range of factors, including technical debt abatement and business strategy. Along with these factors, companies should institutionalize a green ROI metric that is transparent to everybody in the business as an element in IT decision making, including in requests for proposals (RFPs). Doing so will enable companies to better understand the true impact their technology is having on carbon emissions.

Put in place green measurement systems

Establishing a green ROI metric is only a start. CIOs need to establish a baseline of performance, measure progress against the baseline, and track impact in near real time, much as companies track real-time computer and network usage for applications in the cloud. This kind of measuring system ensures that CIOs know what’s working and what isn’t, so they can adjust quickly.

In practice, implementing green measurement can be challenging. Some companies have spent a year measuring their carbon footprint, ending up with an outdated analysis. This tends to happen when companies are determined to measure every bit of carbon emitted, a praiseworthy but time-consuming effort. CIOs can make substantial progress by instead prioritizing measurement where the impact is highest, such as tracking the number of end-user devices purchased and in use, the current duration of use for each device, and the ratio of devices per user. Another way CIOs can make quick progress is to embed emissions- and power-monitoring capabilities into large technology assets and work with external providers, such as electricity companies, to track usage in real time.

Effectively combating climate change won’t happen through one or two big wins; those don’t exist yet. To have real impact, companies and governments will need to act in many areas. Technology has a huge role to play in many of these areas, but CIOs and tech leaders need to act quickly and decisively.

This article is the first in a series about how CIOs can reduce emissions. The next article will explore how CIOs can drive the business’s sustainability agenda by playing offense and implementing reduce, replace, and reuse levers to decarbonize.

Gerrit Becker is an associate partner in McKinsey’s Frankfurt office, Luca Bennici is an associate partner in the Dubai office, Anamika Bhargava is a consultant in the Toronto office, Andrea Del Miglio is a senior partner in the Milan office, Jeffrey Lewis is a senior partner in the New Jersey office, and Pankaj Sachdeva is a partner in the Philadelphia office.

The authors wish to thank Bernardo Betley, Arjita Bhan, Raghuvar Choppakatla, Sebastian Hoffmann, Abdelrahman Mahfouz, Tom Pütz, Jürgen Sailer, Tim Vroman, Alice Yu, and Gisella Zapata for their contributions to this article.

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The Possible Collapse of the U.S. Home Insurance System

A times investigation found climate change may now be a concern for every homeowner in the country..

This transcript was created using speech recognition software. While it has been reviewed by human transcribers, it may contain errors. Please review the episode audio before quoting from this transcript and email [email protected] with any questions.

From “The New York Times,” I’m Sabrina Tavernise. And this is “The Daily.”

[MUSIC PLAYING]

Today, my colleague, Christopher Flavelle, on a “Times” investigation into one of the least known and most consequential effects of climate change — insurance — and why it may now be a concern for every homeowner in the country.

It’s Wednesday, May 15.

So, Chris, you and I talked a while ago about how climate change was really wreaking havoc in the insurance market in Florida. You’ve just done an investigation that takes a look into the insurance markets more broadly and more deeply. Tell us about it.

Yeah, so I cover climate change, in particular the way climate shocks affect different parts of American life. And insurance has become a really big part of that coverage. And Florida is a great example. As hurricanes have gotten worse and more frequent, insurers are paying out more and more money to rebuild people’s homes. And that’s driving up insurance costs and ultimately driving up the cost of owning a home in Florida.

So we’re already seeing that climate impact on the housing market in Florida. My colleagues and I started to think, well, could it be that that kind of disruption is also happening in other states, not just in the obvious coastal states but maybe even through the middle of the US? So we set out to find out just how much it is happening, how much that Florida turmoil has, in fact, become really a contagion that is spreading across the country.

So how did you go about reporting this? I mean, where did you start?

All we knew at the start of this was that there was reason to think this might be a problem. If you just look at how the federal government tracks disasters around the country, there’s been a big increase almost every year in the number and severity of all kinds of disasters around the country. So we thought, OK, it’s worth trying to find out, what does that mean for insurers?

The problem is getting data on the insurance industry is actually really hard. There’s no federal regulation. There’s no government agency you can go to that holds this data. If you talk to the insurers directly, they tend to be a little reluctant to share information about what they’re going through. So we weren’t sure where to go until, finally, we realized the best people to ask are the people whose job it is to gauge the financial health of insurance companies.

Those are rating agencies. In particular, there’s one rating company called AM Best, whose whole purpose is to tell investors how healthy an insurance company is.

Whoa. So this is way down in the nuts and bolts of the US insurance industry.

Right. This is a part of the broader economy that most people would never experience. But we asked them to do something special for us. We said, hey, can you help us find the one number that would tell us reporters just how healthy or unhealthy this insurance market is state by state over time? And it turns out, there is just such a number. It’s called a combined ratio.

OK, plain English?

Plain English, it is the ratio of revenue to costs, how much money these guys take in for homeowner’s insurance and how much they pay out in costs and losses. You want your revenue to be higher than your costs. If not, you’re in trouble.

So what did you find out?

Well, we got that number for every state, going back more than a decade. And what it showed us was our suspicions were right. This market turmoil that we were seeing in Florida and California has indeed been spreading across the country. And in fact, it turns out that in 18 states, last year, the homeowner’s insurance market lost money. And that’s a big jump from 5 or 10 years ago and spells real trouble for insurance and for homeowners and for almost every part of the economy.

So the contagion was real.

Right. This is our first window showing us just how far that contagion had spread. And one of the really striking things about this data was it showed the contagion had spread to places that I wouldn’t have thought of as especially prone to climate shocks — for example, a lot of the Midwest, a lot of the Southeast. In fact, if you think of a map of the country, there was no state between Pennsylvania and the Dakotas that didn’t lose money on homeowner’s insurance last year.

So just huge parts of the middle of the US have become unprofitable for homeowner’s insurance. This market is starting to buckle under the cost of climate change.

And this is all happening really fast. When we did the Florida episode two years ago, it was a completely new phenomenon and really only in Florida. And now it’s everywhere.

Yeah. And that’s exactly what’s so striking here. The rate at which this is becoming, again, a contagion and spreading across the country is just demolishing the expectations of anyone I’ve spoken to. No one thought that this problem would affect so much of the US so quickly.

So in these states, these new places that the contagion has spread to, what exactly is happening that’s causing the insurance companies to fold up shop?

Yeah. Something really particular is happening in a lot of these states. And it’s worth noting how it’s surprised everyone. And what that is, is formally unimportant weather events, like hailstorms or windstorms, those didn’t used to be the kind of thing that would scare insurance companies. Obviously, a big problem if it destroys your home or damages your home. But for insurers, it wasn’t going to wipe them out financially.

Right. It wasn’t just a complete and utter wipeout that the company would then have to pony up a lot of money for.

Exactly. And insurers call them secondary perils, sort of a belittling term, something other than a big deal, like a hurricane.

These minor league weather events.

Right. But those are becoming so frequent and so much more intense that they can cause existential threats for insurance companies. And insurers are now fleeing states not because of hurricanes but because those former things that were small are now big. Hailstorms, wildfires in some places, previous annoyances are becoming real threats to insurers.

Chris, what’s the big picture on what insurers are actually facing? What’s happening out there numbers-wise?

This is a huge threat. In terms of the number of states where this industry is losing money, it’s more than doubled from 10 years ago to basically a third of the country. The amount they’re losing is enormous. In some states, insurers are paying out $1.25 or even $1.50 for every dollar they bring in, in revenue, which is totally unsustainable.

And the result is insurers are making changes. They are pulling back from these markets. They’re hiking premiums. And often, they’re just dropping customers. And that’s where this becomes real, not just for people who surf balance sheets and trade in the stock market. This is becoming real for homeowners around the country, who all of a sudden increasingly can’t get insurance.

So, Chris, what’s the actual implication? I mean, what happens when people in a state can’t get insurance for their homes?

Getting insurance for a home is crucial if you want to sell or buy a home. Most people can’t buy a home without a mortgage. And banks won’t issue a mortgage without home insurance. So if you’ve got a home that insurance company doesn’t want to cover, you got a real problem. You need to find insurance, or that home becomes very close to unsellable.

And as you get fewer buyers, the price goes down. So this doesn’t just hurt people who are paying for these insurance premiums. It hurts people who want to sell their homes. It even could hurt, at some point, whole local economies. If home values fall, governments take in less tax revenue. That means less money for schools and police. It also means people who get hit by disasters and have to rebuild their homes all of a sudden can’t, because their insurance isn’t available anymore. It’s hard to overstate just how big a deal this is.

And is that actually happening, Chris? I mean, are housing markets being dragged down because of this problem with the insurance markets right now?

Anecdotally, we’ve got reports that in places like Florida and Louisiana and maybe in parts of California, the difficulty of getting insurance, the crazy high cost of insurance is starting to depress demand because not everyone can afford to pay these really high costs, even if they have insurance. But what we wanted to focus on with this story was also, OK, we know where this goes eventually. But where is it beginning? What are the places that are just starting to feel these shocks from the insurance market?

And so I called around and asked insurance agents, who are the front lines of this. They’re the ones who are struggling to find insurance for homeowners. And I said, hey, is there one place that I should go if I want to understand what it looks like to homeowners when all of a sudden insurance becomes really expensive or you can’t even find it? And those insurance agents told me, if you want to see what this looks like in real life, go to a little town called Marshalltown in the middle of Iowa.

We’ll be right back.

So, Chris, you went to Marshalltown, Iowa. What did you find?

Even before I got to Marshalltown, I had some idea I was in the right spot. When I landed in Des Moines and went to rent a car, the nice woman at the desk who rented me a car, she said, what are you doing here? I said, I’m here to write a story about people in Iowa who can’t get insurance because of storms. She said, oh, yeah, I know all about that. That’s a big problem here.

Even the rental car lady.

Even the rental car lady knew something was going on. And so I got into my rental car and drove about an hour northeast of Des Moines, through some rolling hills, to this lovely little town of Marshalltown. Marshalltown is a really cute, little Midwestern town with old homes and a beautiful courthouse in the town square. And when I drove through, I couldn’t help noticing all the roofs looked new.

What does that tell you?

Turns out Marshalltown, despite being a pastoral image of Midwestern easy living, was hit by two really bad disasters in recent years — first, a devastating tornado in 2018 and then, in 2020, what’s called a derecho, a straight-line wind event that’s also just enormously damaging. And the result was lots of homes in this small town got severely damaged in a short period of time. And so when you drive down, you see all these new roofs that give you the sense that something’s going on.

So climate had come to Marshalltown?

Exactly. A place that had previously seemed maybe safe from climate change, if there is such a thing, all of a sudden was not. So I found an insurance agent in Marshalltown —

We talked to other agents but haven’t talked to many homeowners.

— named Bobby Shomo. And he invited me to his office early one morning and said, come meet some people. And so I parked on a quiet street outside of his office, across the street from the courthouse, which also had a new roof, and went into his conference room and met a procession of clients who all had versions of the same horror story.

It was more — well more of double.

A huge reduction in coverage with a huge price increase.

Some people had faced big premium hikes.

I’m just a little, small business owner. So every little bit I do feel.

They had so much trouble with their insurance company.

I was with IMT Insurance forever. And then when I moved in 2020, Bobby said they won’t insure a pool.

Some people had gotten dropped.

Where we used to see carriers canceling someone for frequency of three or four or five claims, it’s one or two now.

Some people couldn’t get the coverage they needed. But it was versions of the same tale, which is all of a sudden, having homeowner’s insurance in Marshalltown was really difficult. But I wanted to see if it was bigger than just Marshalltown. So the next day, I got back in my car and drove east to Cedar Rapids, where I met another person having a version of the same problem, a guy named Dave Langston.

Tell me about Dave.

Dave lives in a handsome, modest, little townhouse on a quiet cul-de-sac on a hill at the edge of Cedar Rapids. He’s the president of his homeowners association. There’s 17 homes on this little street. And this is just as far as you could get from a danger zone. It looks as safe as could be. But in January, they got a letter from the company that insures him and his neighbors, saying his policy was being canceled, even though it wasn’t as though they’d just been hit by some giant storm.

So then what was the reason they gave?

They didn’t give a reason. And I think people might not realize, insurers don’t have to give a reason. Insurance policies are year to year. And if your insurance company decides that you’re too much of a risk or your neighborhood is too much of a risk or your state is too much of a risk, they can just leave. They can send you a letter saying, forget it. We’re canceling your insurance. There’s almost no protection people have.

And in this case, the reason was that this insurance company was losing too much money in Iowa and didn’t want to keep on writing homeowner’s insurance in the state. That was the situation that Dave shared with tens of thousands of people across the state that were all getting similar letters.

What made Dave’s situation a little more challenging was that he couldn’t get new insurance. He tried for months through agent after agent after agent. And every company told him the same thing. We won’t cover you. Even though these homes are perfectly safe in a safe part of the state, nobody would say yes. And it took them until basically two days before their insurance policy was going to run out until they finally found new coverage that was far more expensive and far more bare-bones than what they’d had.

But at least it was something.

It was something. But the problem was it wasn’t that good. Under this new policy, if Dave’s street got hit by another big windstorm, the damage from that storm and fixing that damage would wipe out all the savings set aside by these homeowners. The deductible would be crushingly high — $120,000 — to replace those roofs if the worst happened because the insurance money just wouldn’t cover anywhere close to the cost of rebuilding.

He said to me, we didn’t do anything wrong. This is just what insurance looks like today. And today, it’s us in Cedar Rapids. Everyone, though, is going to face a situation like this eventually. And Dave is right. I talked to insurance agents around the country. And they confirmed for me that this kind of a shift towards a new type of insurance, insurance that’s more expensive and doesn’t cover as much and makes it harder to rebuild after a big disaster, it’s becoming more and more common around the country.

So, Chris, if Dave and the people you spoke to in Iowa were really evidence that your hunch was right, that the problem is spreading and rapidly, what are the possible fixes here?

The fix that people seem most hopeful about is this idea that, what if you could reduce the risk and cause there to be less damage in the first place? So what some states are doing is they’re trying to encourage homeowners to spend more money on hardening their home or adding a new roof or, if it’s a wildfire zone, cut back the vegetation, things that can reduce your risk of having really serious losses. And to help pay for that, they’re telling insurers, you’ve got to offer a discount to people who do that.

And everyone who works in this field says, in theory, that’s the right approach. The problem is, number one, hardening a home costs a fantastic amount of money. So doing this at scale is hugely expensive. Number two, it takes a long time to actually get enough homes hardened in this way that you can make a real dent for insurance companies. We’re talking about years or probably decades before that has a real effect, if it ever works.

OK. So that sounds not particularly realistic, given the urgency and the timeline we’re on here. So what else are people looking at?

Option number two is the government gets involved. And instead of most Americans buying home insurance from a private company, they start buying it from government programs that are designed to make sure that people, even in risky places, can still buy insurance. That would be just a gargantuan undertaking. The idea of the government providing homeowner’s insurance because private companies can’t or won’t would lead to one of the biggest government programs that exists, if we could even do it.

So huge change, like the federal government actually trying to write these markets by itself by providing homeowner’s insurance. But is that really feasible?

Well, in some areas, we’re actually already doing it. The government already provides flood insurance because for decades, most private insurers have not wanted to cover flood. It’s too risky. It’s too expensive. But that change, with governments taking over that role, creates a new problem of its own because the government providing flood insurance that you otherwise couldn’t get means people have been building and building in flood-prone areas because they know they can get that guaranteed flood insurance.

Interesting. So that’s a huge new downside. The government would be incentivizing people to move to places that they shouldn’t be.

That’s right. But there’s even one more problem with that approach of using the government to try to solve this problem, which is these costs keep growing. The number of billion-dollar disasters the US experiences every year keeps going up. And at some point, even if the government pays the cost through some sort of subsidized insurance, what happens when that cost is so great that we can no longer afford to pay it? That’s the really hard question that no official can answer.

So that’s pretty doomsday, Chris. Are we looking at the end of insurance?

I think it’s fair to say that we’re looking at the end of insurance as we know it, the end of insurance that means most Americans can rest assured that if they get hit by a disaster, their insurance company will provide enough money they can rebuild. That idea might be going away. And what it shows is maybe the threat of climate change isn’t quite what we thought.

Maybe instead of climate change wrecking communities in the form of a big storm or a wildfire or a flood, maybe even before those things happen, climate change can wreck communities by something as seemingly mundane and even boring as insurance. Maybe the harbinger of doom is not a giant storm but an anodyne letter from your insurance company, saying, we’re sorry to inform you we can no longer cover your home.

Maybe the future of climate change is best seen not by poring over weather data from NOAA but by poring over spreadsheets from rating firms, showing the profitability from insurance companies, and how bit by bit, that money that they’re losing around the country tells its own story. And the story is these shocks are actually already here.

Chris, as always, terrifying to talk to you.

Always a pleasure, Sabrina.

Here’s what else you should know today. On Tuesday, the United Nations has reclassified the number of women and children killed in Gaza, saying that it does not have enough identifying information to know exactly how many of the total dead are women and children. The UN now estimates that about 5,000 women and about 8,000 children have been killed, figures that are about half of what it was previously citing. The UN says the numbers dropped because it is using a more conservative estimate while waiting for information on about 10,000 other dead Gazans who have not yet been identified.

And Mike Johnson, the Speaker of the House, gave a press conference outside the court in Lower Manhattan, where Michael Cohen, the former fixer for Donald Trump, was testifying for a second day, answering questions from Trump’s lawyers. Trump is bound by a gag order. So Johnson joined other stand-ins for the former president to discredit the proceedings. Johnson, one of the most important Republicans in the country, attacked Cohen but also the trial itself, calling it a sham and political theater.

Today’s episode was produced by Nina Feldman, Shannon Lin, and Jessica Cheung. It was edited by MJ Davis Lin, with help from Michael Benoist, contains original music by Dan Powell, Marion Lozano, and Rowan Niemisto, and was engineered by Alyssa Moxley. Our theme music is by Jim Brunberg and Ben Landsverk of Wonderly.

That’s it for “The Daily.” I’m Sabrina Tavernise. See you tomorrow.

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• May 17, 2024   •   51:10 The Campus Protesters Explain Themselves
• May 16, 2024   •   30:47 The Make-or-Break Testimony of Michael Cohen
• May 15, 2024   •   27:03 The Possible Collapse of the U.S. Home Insurance System
• May 14, 2024   •   35:20 Voters Want Change. In Our Poll, They See It in Trump.
• May 13, 2024   •   27:46 How Biden Adopted Trump’s Trade War With China
• May 10, 2024   •   27:42 Stormy Daniels Takes the Stand
• May 9, 2024   •   34:42 One Strongman, One Billion Voters, and the Future of India
• May 8, 2024   •   28:28 A Plan to Remake the Middle East
• May 7, 2024   •   27:43 How Changing Ocean Temperatures Could Upend Life on Earth
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Hosted by Sabrina Tavernise

Featuring Christopher Flavelle

Produced by Nina Feldman ,  Shannon M. Lin and Jessica Cheung

Edited by MJ Davis Lin

With Michael Benoist

Original music by Dan Powell ,  Marion Lozano and Rowan Niemisto

Engineered by Alyssa Moxley

Listen and follow The Daily Apple Podcasts | Spotify | Amazon Music | YouTube

Across the United States, more frequent extreme weather is starting to cause the home insurance market to buckle, even for those who have paid their premiums dutifully year after year.

Christopher Flavelle, a climate reporter, discusses a Times investigation into one of the most consequential effects of the changes.

On today’s episode

Christopher Flavelle , a climate change reporter for The New York Times.

Background reading

As American insurers bleed cash from climate shocks , homeowners lose.

See how the home insurance crunch affects the market in each state .

Here are four takeaways from The Times’s investigation.

There are a lot of ways to listen to The Daily. Here’s how.

We aim to make transcripts available the next workday after an episode’s publication. You can find them at the top of the page.

Christopher Flavelle contributed reporting.

The Daily is made by Rachel Quester, Lynsea Garrison, Clare Toeniskoetter, Paige Cowett, Michael Simon Johnson, Brad Fisher, Chris Wood, Jessica Cheung, Stella Tan, Alexandra Leigh Young, Lisa Chow, Eric Krupke, Marc Georges, Luke Vander Ploeg, M.J. Davis Lin, Dan Powell, Sydney Harper, Mike Benoist, Liz O. Baylen, Asthaa Chaturvedi, Rachelle Bonja, Diana Nguyen, Marion Lozano, Corey Schreppel, Rob Szypko, Elisheba Ittoop, Mooj Zadie, Patricia Willens, Rowan Niemisto, Jody Becker, Rikki Novetsky, John Ketchum, Nina Feldman, Will Reid, Carlos Prieto, Ben Calhoun, Susan Lee, Lexie Diao, Mary Wilson, Alex Stern, Dan Farrell, Sophia Lanman, Shannon Lin, Diane Wong, Devon Taylor, Alyssa Moxley, Summer Thomad, Olivia Natt, Daniel Ramirez and Brendan Klinkenberg.

Our theme music is by Jim Brunberg and Ben Landsverk of Wonderly. Special thanks to Sam Dolnick, Paula Szuchman, Lisa Tobin, Larissa Anderson, Julia Simon, Sofia Milan, Mahima Chablani, Elizabeth Davis-Moorer, Jeffrey Miranda, Renan Borelli, Maddy Masiello, Isabella Anderson and Nina Lassam.

Christopher Flavelle is a Times reporter who writes about how the United States is trying to adapt to the effects of climate change. More about Christopher Flavelle

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Ongoing Brazil floods raise specter of climate migration

MUCUM, Brazil — Devastating and ongoing  flooding  in southern Brazil is forcing some of the half million displaced residents to consider uprooting their lives from inundated towns to rebuild on higher ground.

Two weeks after the onset of torrential rains, the Guaiba River running by state capital Porto Alegre is rising again, having passed the all-time high. In the state of Rio Grande do Sul, the streets of dozens of towns have turned into slow-moving rivers.

Just in the area around Porto Alegre, where four rivers converge to form the Guaiba River, researchers estimate nearly 3,800 square km (1,500 square miles) were flooded. That is more than the urban footprint of the Washington DC metro area, which includes 10 counties in two adjacent states.

With hundreds of thousands of families fleeing the floods, the disaster — which has killed at least 147 people, with 127 still missing — could touch off one of Brazil’s biggest cases of climate migration in recent history.

Southern Brazil’s location at the confluence of tropical and polar currents has fed periods of increasingly intense drought and rains due to climate change, according to scientists.

The record devastation in Rio Grande do Sul follows floods in the second half of last year, leading many of the 538,000 people now displaced from their homes to consider more extreme adaptations.

For the third time in seven months, businessman Cassiano Baldasso had to remove wheelbarrows of mud from his home in Muçum, a small town 150 km (90 miles) upriver from Porto Alegre, only to see the waters rise again. He says he has had enough.

“I have no idea where I’m going, but it will be somewhere far from the river, where our lives will not be at risk,” Baldasso told Reuters as he removed another cart of mud from inside the house.

Mayor Mateus Trojan said many of Muçum’s 5,000 residents will have to relocate. His office is planning to rebuild 40% of the town elsewhere.

Baldasso had already saved his family in September by climbing onto the roof of their two-story house until they were rescued by the fire brigade in the middle of the night.

During that flood, just a few blocks away, Maria Marlene Venancio’s house was swept away and she lost everything. This month, the rented house she had moved to was flooded 1.5 meters (5 ft) deep. She fears it is time to leave Muçum.

“I think the town will become a river one day, and it will be difficult for us to live here. People with money are all leaving,” she said.

Governor Eduardo Leite has said initial calculations show Rio Grande do Sul will need at least 19 billion reais ($3.7 billion) to rebuild from the disaster. The federal government has offered to freeze 11 billion reais of debt payments for three years.

On the streets of Muçum and other nearby towns, the slowly receding waters leave desolate scenes of furniture, clothing and appliances piled up in front of the houses.

Maria Ines Silverio has returned to her house, but she keeps her clothes in plastic bags for fear of the river rising again. She has a 30-year mortgage and says she cannot afford to leave.

“When we bought the house, this wasn’t a flooded area. Now it is, and the river is going to rise more and more,” she said.

Environmental experts warn that there is no alternative for some towns in the state but to relocate entire neighborhoods.

“We need to move urban infrastructure away from high-risk environments and return space to the rivers ... so they no longer impact cities with such magnitude,” said ecologist Marcelo Dutra, professor at the Rio Grande Federal University.

“We can’t oppose nature. We have to wake up to this force that is telling us we need to adapt and respect nature,” he said.