Know Climate Change

Impacts of Climate Change

Impacts on Health

Impact of climate change on human health can be of two types.

  • Direct Impacts: Increased mortality due to heat/cold waves, floods, droughts, cyclones, poisonous gases, and so on.
  • Indirect Impacts: Increased health problems due to vectors, contaminated food and water, malnutrition due to reduced food production.

The diagram below summarizes some of the main pathways (both direct and indirect impacts) and categories of health impact of climate change.

Pathways by which climate change may affect human health
Source: Mc Michael et al., 2003

Various impacts of climate change and their interrelation with human health are summarized below.


Findings from Research

  • Increases in malnutrition and consequent disorders, with implications for child growth and development
  • Increased number of deaths, diseases, and injuries due to heat waves, floods, storms, fires, and droughts
  • Increased burden of diarrhoeal disease
  • Mixed effects on the range (increases and decreases) and transmission potential of malaria in Africa
  • Increased frequency of cardio-respiratory diseases due to higher concentrations of ground-level ozone related to climate change
  • Altered spatial distribution of some infectious-disease causing vectors

Heat Wave in Europe, 2003
In August 2003, a heat wave that emanated from...

In August 2003, a heat wave that emanated from France spread across Europe and caused more than 14,800 deaths in Belgium, the Czech Republic, Germany, Italy, Portugal, Spain, Switzerland, the Netherlands and the UK. All these countries reported excess mortality during the heat-wave period, with total deaths in the range of 35,000. In France, around 60% of the heat wave deaths occurred in persons aged 75 and above. Other harmful exposures were also caused or exacerbated by the extreme weather, such as outdoor air pollutants and pollution from forest fires. A French parliamentary inquiry concluded that the health impact was ‘unforeseen’, surveillance for heat-wave deaths was inadequate, and the limited public-health response was due to a lack of experts, limited strength of public-health agencies, and poor exchange of information between public organizations (IPCC, 2007).