Statistics on Climate Change

Graphic of Impact of Climate Change on Human Health

Graphic is from the Centers for Disease Control Climate Effects on Health


Statistics below are from the World Bank (2018) on Climate Change and Health.

Climate change – experienced primarily through shifts in temperature, rainfall, sea - level rise and weather volatility – can have drastic impacts on human health.

  • Climate change could see more than 100 million people return to extreme poverty by 2030 unless concerted action is taken. The negative impacts of climate change on people’s health could play a major role in this reversal.

  • Not all of these impacts will fall on future populations: climate change is already having measurable impacts on human health.

Climate change influences health through changing the distribution and occurrence of vector-borne diseases.

  • Warming of 2-3°C is estimated to increase the number of people at risk of malaria by up to 5 percent globally, or more than 150 million people.

  • Climate change is also closely linked with increased incidence of dengue – a mosquito-borne disease whose transmissibility has increased by between 3% and 6% due to climate change since 1990.

  • Climate change could increase the burden of diarrhea by up to 10 percent by 2030 in susceptible regions, such as South-East Asia.

The combined effects of higher temperatures, increasing rainfall volatility and weather extremes have dire impacts on crops. In the extreme, climate change can result in complete crop failure. 

  • For these reasons, undernutrition (the outcome of insufficient food intake and repeated infectious diseases) has been identified as the largest health impact of climate change in the 21st century.
  • A 6% decline in global wheat yields and 10% decline in rice yields is expected for each additional 1°C rise in global temperature, with substantial impacts on undernutrition and stunting in food-insecure or poor regions. An additional 7.5 million children are expected to be stunted by 2030, 4 million of whom are expected to be affected by severe stunting, increasing to 10 million children by 2050. 

The impacts of weather-related disasters on the health of people expand beyond mortality and include injuries, mental health issues, the spread of disease, food, and water insecurity, and limited access to healthcare and other basic services. 

  • The frequency of weather-related disasters has increased by 46% from 2007-2016 (compared to the 1990s) due to climate change.

  • These disasters result in over 60, 000 deaths annually, mainly in developing countries.

  • A growing literature on the links between climate change and mental health has begun to examine the direct and indirect causal pathways that impact mental health, including the psychological consequence of disasters and economic losses on mental health, drought and farmer suicide, migration and forced displacement, and physical illness.

Air pollution is the fourth-leading risk factor for deaths worldwide. 

  • Many of the same pollutants responsible for climate change also affect human health through air quality impacts that are linked to respiratory and cardiac threats, as well as certain cancers.
  • Climate drivers that affect health include fine particulate matter (including black carbon which is a strong warming agent) and methane, which contributes to the formation of ground-level ozone or smog.

  • In 2013, 87% of the world’s population lived in areas that exceed the World Health Organization’s air quality guidelines.

  • Air pollution is already responsible for more than 7 million premature deaths each year; 1 in 10 deaths is attributable to air pollution exposure.

  • While pollution-related deaths mainly strike children and the elderly, pollution also results in lost labor income for working-age men and women.

Low-and middle-income countries are seeing the worst health effects from climate change as they tend to be more vulnerable to climate shifts and least able to adapt given weak health systems and low access to basic services.

  • Climate change exacerbates social, economic, and demographic inequalities by straining the social and environmental systems that support good health.
  • The number of vulnerable people exposed to heatwave events increased by 125 million between 2000 and 2016.

The economic impact of climate change on health is striking.

  • The economic costs of climate change on health are difficult to calculate because of the many associated environmental and social determinants of health. Nevertheless, there are some valid economic quantifications of health and climate relationships:
    • By 2030, the direct costs from damage to health (excluding costs in health-determining sectors such as agriculture, water, and sanitation) could reach between $US 2 billion and $4 billion per year by 2030.

    • The economic costs associated with the air pollution-related burden of disease correspond to US $1.7 trillion of lost output annually in OECD countries, US $1.4 trillion in China, and US $500 billion in India.

    • Labor productivity losses due to excess heat may be as much as 11–20 percent in heat-prone regions such as Asia and the Caribbean by 2080.

Without adequate investment in health sector resilience, recent development gains are at risk. 

  • Pathways to resilient health sectors are possible, building on the growing evidence-base of understanding of the threats climate change imposes on health.

  • Many countries and development institutions have recognized the importance of building climate resilience into the health sector. 121 of 184 (66%)  Nationally Determined Contributions (NDCs) include references to climate change’s impacts on health, driven by strong support for action in many developing countries (90% of African states, 69% of Asian states, 82% of Latin American states).

  • Conversely, only 15% of countries that have developed national climate change action plans referred to health.

  • Health and health-related adaptation funding account for only 13.3 percent ($47.3bn) of total global adaptation spending.