Climate and health

Fact sheet, July 2005

From the tropics to the arctic, both climate and weather have powerful impacts, both direct and indirect, on human life. While people adapt to the conditions in which they live, and human physiology can handle substantial variation in weather, there are limits.

Marked short-term fluctuations in weather can cause acute adverse health effects:

• Extremes of both heat and cold can cause potentially fatal illnesses, e.g. heat stress or hypothermia, as well as increasing death rates from heart and respiratory diseases.
• In cities, stagnant weather conditions can trap both warm air and air pollutants — leading to smog episodes with significant health impacts.
• These effects can be significant. Abnormally high temperatures in Europe in the summer of 2003 were associated with at least 27,000 more deaths than the equivalent period in previous years¹ .

Other weather extremes, such as heavy rains, floods, and hurricanes, also have severe impacts on health. Approximately 600,000 deaths occurred world-wide as a result of weather-related natural disasters in the 1990s; and some 95% of these were in poor countries. Some examples:

• In October 1999, a cyclone in Orissa, India, caused 10,000 deaths. The total number of people affected was estimated at 10-15 million;
• In December 1999, floods in and around Caracas, Venezuela, killed approximately 30,000 people, many in shanty towns on exposed slopes.

In addition to changing weather patterns, climatic conditions affect diseases transmitted through water, and via vectors such as mosquitoes. Climate-sensitive diseases are among the largest global killers. Diarrhoea, malaria and protein-energy malnutrition alone caused more than 3.3 million deaths globally in 2002, with 29 % of these deaths occurring in the Region of Africa. Read More …….