Climate Change
Climate Change

Another potential threat that could have a significant impact on global human health comes from the possibility of climate change. The predicted rise of average global temperatures due to human behavior (from the burning of fossil fuels, use of other chemicals, and the cutting down of forests) has been increasingly accepted by international scientists.

A report by the Intergovernmental Panel on Climate Change (IPCC) found that:

Projected climate change will be accompanied by an increase in heat waves, often exacerbated by increased humidity and urban air pollution, which would cause an increase in heat-related deaths and illness episodes. The evidence indicates that the impact would be greatest in urban populations, affecting particularly the elderly, sick and those without access to air-conditioning.

Many climate models indicate that the world is likely to become significantly wetter as a result of the warming processmeaning that rainfall is likely to increase in many areas.

This rise in temperatures and moisture would significantly expand the natural habitats of mosquitoes, which carry malaria and other diseases. A report by the National Institute of Public Health and Environmental Protection in the Netherlands calculated that the predicted global mean temperature rise of three degrees Celsius by 2100 would double the potential for malaria epidemics in tropical regions, and increase the potential in temperate zones by more than 10 times (cited in McGinn).

Similarly, the southwestern United States has been affected by the emergence of the previously unknown Hanta virus. Mice spread this microbe, which is extremely deadly. The recent appearance of the disease in humans has been linked to an exponential increase in the population of mice in the region brought about by significantly increased rainfalls. The heavier rains have been attributed to the El Nino effect.

Although some scientists question whether the apparently increased severity of the El Nino effect is a result of global warming, the phenomenon is nonetheless believed to provide an accurate model for how rainfall would increase due to overall global warming.

The report by the IPCC also predicts that the increase in global mean temperatures will lead to increased flooding in coastal areas, which “will increase the risk of drowning, diarrheal and respiratory diseases, and in developing countries, hunger and malnutrition.”

Questions for Discussion:

Have you visited any of the “mega-cities” that are developing around the world (like New York, Tokyo, Mexico City and Moscow)? What conditions did you encounter?

Assume you were the mayor of Los Angeles. How would you go about reducing the spread of disease in your city? Would you regulate construction? Offer free immunizations against certain diseases? Now assume you were the mayor of Jakarta. Would you be able to adopt the same policies? How would your approach differ?

For additional information on human health and climate change, please click here.



Next: Localized Environmental Concerns