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 the social and environmental determinants of health, such as clean air, clean water, sufficient food, and a safe haven. Additionally, extremely high air temperatures directly contribute to deaths from cardiovascular and respiratory diseases, especially among older people. In the summer heat wave of 2003 in Europe, for example, more than 70,000 excess deaths were recorded (UNEP, 2004, March). Remarkably hot temperatures also raise levels of ozone and other pollutants in the air that exacerbate cardiovascular and respiratory diseases.

Globally, the number of reported climate-related natural disasters has more than tripled since the 1960s. Each year, these disasters cause more than 60,000 deaths, mainly in developing countries (WHO, 2017, July). In connection with rising sea levels and increasingly extreme weather events, in particular, homes, medical facilities and other essential services will be destroyed. More than half of the world’s population lives less than 60 km from the sea (Creel, 2003, September). And people can be forced to move, which in turn increases the risk of a variety of health effects, from mental disorders to communicable diseases. Increasingly variable rainfall patterns are likely to affect freshwater supplies. Lack of clean water can compromise hygiene and increase the risk of diarrheal diseases, which kill thousands of children under the age of 5 each year. In extreme cases, water scarcity leads to droughts and famines.

Floods are also increasing in frequency and intensity, and the frequency and intensity of extreme rainfall is expected to continue to increase throughout the current century. Floods contaminate freshwater supplies, increase the risk of waterborne diseases, and create a breeding ground for disease-carrying insects such as mosquitoes. They also cause drowning and physical injury, damage homes, and disrupt the provision of health and medical services.

In addition, weather conditions strongly affect waterborne diseases and diseases transmitted through insects, snails, or other cold-blooded animals. Climate changes are likely to lengthen the transmission seasons of important vector-borne diseases and alter their geographic distribution. For example, climate change is projected to significantly expand the area of ​​China where schistosomiasis, a snail-borne disease, occurs (WHO, 2009). Malaria is strongly influenced by the weather. Transmitted by Anopheles mosquitoes, malaria kills more than 400,000 people each year, mainly African children under 5 years of age (WHO, 2017, April).

In short, climate change typically affects all populations, but some are more vulnerable than others. People living in small island developing states and other coastal regions, megacities, and mountainous and polar regions are particularly vulnerable. Children, particularly children living in poor countries who are among the most vulnerable to the resulting health risks and will be exposed to health consequences for the longest time.

Reference

Ottmar Edenhofer, RP-M. (2014). GDS Summary for Policymakers.

UNA P. (2004, March). Impacts of the 2003 summer heat wave in Europe. Environmental alert bulletin.

Organization, WH (2017, July). Climate change and health. Media Center.

Creel, L. (2003, September). Domino effects: population and coastal regions. Population Reference Office.

WHO. (2009). Climate change and health. WHO Representative Office in China.

WHO. (2017, April). Malaria. Media Center.