Global warming and climate change can affect human health by altering the geographic range and seasonality of certain infectious diseases. Food-producing ecosystems may be disturbed and make it difficult to ensure adequate nutrition in many areas. Increasing frequency of extreme weather events, such as hurricanes, droughts and floods may destroy infrastructure and in instances make it impossible to treat sewage properly and secure clean freshwater to households.
Although global warming may bring some localized benefits, such as fewer winter deaths in temperate climates and increased food production in certain areas, the overall health effects of a changing climate are likely to be overwhelmingly negative. Climate change affects social and environmental determinants of health – clean air, safe drinking water, sufficient food and secure shelter.
Extreme high air temperatures contribute directly to deaths from cardiovascular and respiratory disease, particularly among elderly people. In the heat wave of summer 2003 in Europe for example, more than 70 000 excess deaths were recorded2.
High temperatures also raise the levels of ozone and other pollutants in the air that exacerbate cardiovascular and respiratory disease.
Pollen and other aeroallergen levels are also higher in extreme heat. These can trigger asthma, which affects around 300 million people. Ongoing temperature increases are expected to increase this burden.
Globally, the number of reported weather-related natural disasters has more than tripled since the 1960s. Every year, these disasters result in over 60 000 deaths, mainly in developing countries.
Rising sea levels and increasingly extreme weather events will destroy homes, medical facilities and other essential services. More than half of the world’s population lives within 60 km of the sea. People may be forced to move, which in turn heightens the risk of a range of health effects, from mental disorders to communicable diseases. WHO Fact Sheet (2015) Climate change and health
- WHO (2015) Climate change and health
- WHO: Burden of disease from ambient and household air pollution
- Lancet (2016) Global and regional health effects of future food production under climate change: a modelling study
- Alternet (2016) How Just One Consequence of Climate Change Will Cause 500,000 to Die by 2050 With global temperatures rising, researchers predict there will be fewer healthy fruits and veggies to go around in the future
- Climate change not a big killer?
- Climate Change and Health (World Bank)
- Study links global warming to rise in waterborne illnesses
- El Niño on a warming planet may have sparked the Zika epidemic, scientists report (Dec 2016)
- Anthropocentric view ignores crucial connections
- New Doctors’ Group Highlights Climate Change’s Urgent Threat to Health Nationwide (March 2017)
- Taxpayers Give Billions in Fossil Fuel Subsidies, Lose Trillions to Related Health Costs (July 2017)
- Thousands hit by malaria, dengue as South Asia’s worst floods in a decade recede (Sept 2017)
- Lancet: Pollution – a global health crisis (2017)
- Pollution is one of the world’s biggest killers, a new study says |(Oct 2017)
- Study: Climate Change Is Damaging the Health of Millions of People (Time, Oct 2017)
- Toxic algae: Once a nuisance, now a severe nationwide threat (Nov 2017)
|Home||Chapter 3||3. Impacts|
|3.1 More water vapor|
|3.2 Sea level rise|
|3.3 Polar sea ice|
|3.4 Air pollution|
|3.7 Extreme weather|
|3.9 Refugees and conflicts|
|3.11 Tipping points|
|Chapter 4||4. Ecosystems|