The 2020 Report

No continent, country or community is immune from the health impacts of climate change.

Aligning the global COVID-19 recovery with our response to climate change offers the chance to protect health, promote a sustainable economy, and preserve our planet. Our 2020 Report tracks the relationship between health and climate change across five key domains and over 40 indicators.

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Key message

No country – whether rich or poor – is immune from the health impacts of climate change. Right now, people around the world face increasing extremes of heat, food and water insecurity, and changing patterns of infectious diseases. Unless urgent action is taken, the health impacts of climate change will bring further disruption, threaten lives and livelihoods and compromise the hospitals and clinics we depend on.

Key message

The COVID-19 pandemic and climate change represent converging crises. Wildfires and tropical storms in 2020 have tragically shown us that we don’t have the luxury of tackling one crisis alone. At the same time, climate change and infectious disease share common drivers. Responding to climate change today will bring about cleaner skies, healthier diets, and safer places to live–as well as reduce the risk factors of future infectious diseases.

Key message

Aligning the global recovery from COVID-19 with our response to climate change offers a triple win: improve public health, create a sustainable economy, and protect the environment. But time is short. Failure to tackle these converging crises in tandem would move the world’s 1.5C target out of reach, damaging the health of the world’s 7.8 billion citizens in the short and long-term.

Explore key findings of this year’s report

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Health Hazards, Exposures, and Impacts

Climate Change Impacts, Exposure and Vulnerability

A changing climate has profound implications for human health, with more frequent heatwaves and extreme weather events, changing patterns of infectious disease, and the exacerbation of existing health challenges around the world. Indicators in this section track how these impact on human health.

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Adaptation, Planning, and Resilience for Health

Adaptation, Planning, and Resilience for Health

Indicators in this section track how communities, health systems, and governments are understanding the health risks of climate change, the strategies and resources they are deploying, and how adaptation and resilience measures are being implemented globally.

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Mitigation Actions and Health Co-Benefits


Tackling climate change could be the greatest global health opportunity of the 21st century. Many of the interventions required to mitigate and adapt bring enormous benefits for human health and wellbeing in the form of cleaner air, healthier diets, and more liveable cities. Indicators in this section track the world’s efforts to mitigate climate change, and the health benefits of this response.

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Economics and Finance

Economics and Finance

The data here works to track the financial and economic dimensions of the effects of climate change, and of mitigation efforts required to respond to these changes. Indicators here monitor the economic costs of climate change and its drivers, as well as the investments and economic tools being deployed to transition to a low-carbon economy.

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Public and Political Engagement

Public and Political Engagement

Public and political engagement underpins the foundations of the world’s collective response to climate change, with reductions in global emissions at the speed required by the Paris Agreement depending on engagement from all sectors of society. The indicators in this section track the links between health and climate change in the media, national governments, the corporate sector, and the broader public.

  • Icon_1_Green Created with Sketch. Health Hazards, Exposures, and Impacts
    • 1.1.2 Exposure of Vulnerable Populations to Heatwaves

      Vulnerable populations – the elderly and children under 1 year of age - faced 3.7 billion more life-threatening heatwave days in 2021 than annually in 1986-2005, putting them at acute risk of heat stress, heat stroke, and other adverse physical and mental health manifestations.

    • 1.2.1 Wildfires

      Drier and hotter weather is making conditions increasingly suitable for the start and spread of wildfires, putting people' s health and safety at risk. Human exposure to days of very-high or extremely-high fire danger increased in 61% of countries from 2001–2004 to 2018–2021.

    • 1.2.2 Drought

      Droughts put food and water security at risk, threaten sanitation, affect livelihoods, and increase the risk of wildfires and infectious disease transmission. On average, 29% more global land area was affected by extreme drought for at least one month in a year in 2012–21 than in 1951–60

    • 1.3 Climate Suitability for Infectious Disease Transmission

      Climate change is affecting the distribution and transmission of many infectious diseases, including vector-borne, food-borne, and waterborne diseases. The climatic suitability for the transmission of dengue increased by 11·5% for Aedes aegypti and 12·0% for Aedes albopictus from 1951–60 to 2012–21

    • 1.4 Food Security and Undernutrition

      The increasing frequency of heatwaves resulted in an additional 98 million people reporting moderate to medium food insecurity in the 103 countries analysed in 2020, compared to the 1981-2010 average. This threatens to compound the impacts on food insecurity of the COVID-19 pandemic, and the energy and cost of living crises.

  • Icons Final_Green-03 Created with Sketch. Adaptation, Planning, and Resilience for Health
    • 2.1.1 National Assessments of Climate Change Impacts, Vulnerability and Adaptation for Health/2.1.2 National Adaptation Plans for Health

      nsufficient climate change adaptation efforts have left health systems vulnerable to climate change-related health hazards. Only 48 of 95 countries have completed a climate change and health vulnerability and adaptation assessment, and in only 9 countries did these strongly influenced resource allocation.

    • 2.2.3 Urban Green Space

      Healthy and green urban redesign will promote physical activity and deliver more friendly, liveable cities. Today, just 27% of urban centres are classified as moderately-green or above.

    • 2.2.5 Detection, Preparedness and Response to Health Emergencies

      Even after the impact of the COVID-19 pandemic, only 63% of 177 countries reported high to very high implementation status for health emergency management in 2021, with only 35% of low or medium Human Development Index countries doing so.

  • Icons Final_Green_v2-03 Created with Sketch. Mitigation Actions and Health Co-Benefits
    • 3.1 Energy System and Health

      Energy systems are the largest single source of greenhouse gas emissions and are major contributors to air pollution. CO2 emissions from fossil fuel combustion reached a record high in 2020. The carbon intensity from the energy system decreased by less than 1% since the year countries came together to adopt the UN Framework Convention on Climate Change.

    • 3.2 Clean Household Energy

      Dirty fuels still dominate the energy used in the domestic sector. Just 13% of rural households in low Human Development Index (HDI) countries had access to clean fuels and technologies for cooking in 2020, against 98% in high HDIcountries. In the 63 countries assessed, the air in people’s homes exceeded WHO small particulate pollution (PM2.5) guideline levels by 30-fold in 2020

    • 3.3 Premature Mortality from Ambient Air Pollution by Sector

      Transition towards sustainable energy, transportation, waste management and agricultural systems could help prevent the 3·3 million deaths attributable to anthropogenic PM2.5 in 2020, including the 1·2 million directly related to the combustion of fossil fuels

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    • 4.1.3 Loss of Earnings from Heat-Related Labour Capacity Loss

      Heat exposure in 2021 led to income losses equivalent to substantial proportions of countries’ GDP (5.6% in the case of low Human Development Index countries), worsening the impact of the cost-of-living crisis, and worsening the socioeconomic conditions that contribute to good health.

    • 4.2.4 Net Value of Fossil Fuel Subsidies and Carbon Prices

      Despite their profound health harms, governments continue to encourage fossil fuel production and consumption. 69 (80%) of 86 countries reviewed had net-negative carbon prices (ie, provided a net subsidy to fossil fuels) for a net total of US$400 billion. These subsidies exceeded 10% of national health spending in 31 countries and exceeded 100% in 5 countries

    • 4.2.6 Compatibility of Fossil Fuel Company Strategies With the Paris Agreement

      Despite climate commitments to reduce their carbon impact, on the basis of their existing production strategies and market shares, 15 of the largest oil and gas companies would exceed their share of greenhouse gas emissions compatible with the 1·5°C climate target by an average of 87% (publicly-listed international companies) and 111% (state-owned national companies) in 2040, making the goals of the Paris Agreement unattainable

  • Icons Final_Green_v2-06 Created with Sketch. Public and Political Engagement
    • 5.1 Media Coverage of Health and Climate Change

      Media articles are a widely used source of public information that influence public perceptions on climate change, governments, and the social media agenda. Coverage of health and climate change in the media increased by 4.7% in 2021 from 2020, reaching a record high.

    • 5.4 Government Engagement in Health and Climate Change

      Government engagement with health and climate change is essential for health-centred climate action. Engagement with health and climate change from world leaders has increased since 2020, with 60% of countries drawing attention to climate change and health in the 2021 UN General Debate, and 86% of the updated NDC submissions referring to health

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News & Events

News & Events



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