Physicians have long noted that deaths spike during heat waves. Compared to periods of normal temperature, more people die of heart attack and stroke during hot periods. And hot periods are also associated with the greater formation of ozone and other air pollutants that exacerbate respiratory illnesses such as asthma and emphysema. Electricity generation for air conditioning peaks on hot summer days.
The changes in mortality are not trivial. Over a thirty-year period, Daniel Astrom of Umea University in Sweden found that there were twice as many deaths in Stockholm as a result of high temperature events associated with climate change. The result was a combination of both higher temperatures and more frequent extreme heat events.
Some have argued that a warmer climate will be less stressful to human health, by lowering the incidence and severity of flu and the number of accidents due to icy conditions. Examining the net impacts on mortality, Dr. Tiantian Li and his colleagues from Columbia University estimate a 5.3 to 6.2% increase in mortality in Manhattan by 2020 due to climate change, with greater increases later in the century.
The health effects of climate change are not simply confined to cities. Climate change is also likely to exacerbate mortality from insect-borne diseases such as malaria that are spread by mosquitoes. Mosquitoes like warm, wet conditions and a long growing season to reproduce.
These results from Stockholm and Manhattan argue that a warmer climate will take a toll on human life that we should not overlook.
**********
.
Web Links
Photo, taken on July 14, 2012, courtesy of David Prasad via Flickr.
.
Earth Wise is a production of WAMC Northeast Public Radio. Support for Earth Wise comes from the Cary Institute of Ecosystem Studies in Millbrook, NY.