Is global warming a threat to humans? If so, how?

January 23, 2014

Yes, health care providers and insurers alike recognize that global warming is a threat to humans. The major public health organizations of the world have said that climate change is a critical public health problem. According to the U.S. National Institute of Environmental Health Sciences, climate change makes many existing diseases and conditions worse, and it helps pests and pathogens spread into new regions. The most vulnerable people—children, the elderly, the poor, and those with health conditions—are at increased risk for climate-related health effects.

Edward Butcher, 64, looks out into the street as he sits near the window to stay cool in his non-air conditioned apartment on a sweltering Wednesday, Aug. 2, 2006 in the Ridgewood section of the Queens borough of New York. AP Photo/Jason DeCrow.

Global warming is also a threat to the economy and national security in many developing nations. Because societies and their built environments have developed under a climate that has fluctuated within a relatively small range of conditions, most impacts of a rapidly changing climate will present challenges—particularly as extreme weather and climate conditions become more extreme, more frequent, and longer lasting. In developing nations, populations are much more vulnerable to weather and climate extremes and are less able to adapt. Any climate-related impacts on scarce natural resources, food, and water are more likely to trigger humanitarian crises or armed conflicts that can destabilize nations, or whole regions.

In the United States, the most rapidly growing population is in the Mountain West. That region is projected to experience more frequent and more severe wildfires with less water availability, particularly during the high-demand period of summer. Because of high demand for irrigating agriculture, overuse of rivers and streams is common in the arid West, particularly along the Front Range of the Rocky Mountains in Colorado, in Southern California, and in the Central Valley of California. Rapid population and economic growth in these arid and semi-arid regions has dramatically increased people's vulnerability to water shortages.


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USGCRP (2009): Global Climate Change Impacts in the United States. A special report of the United States Global Change Research Program [T.R. Karl, J.M. Melillo, and T.C. Peterson (eds.)]. Cambridge University Press, New York, NY, USA, 188 pp.

Portier, C.J., K. Thigpen-Tart, S.R. Carter, C.H. Dilworth, A.E. Grambsch, J. Gohlke, J. Hess, S.N. Howard, G. Luber, J.T. Lutz, T. Maslak, N. Prudent, M. Radtke, J.P. Rosenthal, T. Rowles, P.S. Sandifer, J. Scheraga, P.J. Schramm, D. Strickman, J.M. Trtanj, P-Y Whung (2010): A Human Health Perspective On Climate Change:A Report Outlining the Research Needs on the Human Health Effects of Climate Change. Research Triangle Park, NC: Environmental Health Perspectives/National Institute of Environmental Health Sciences. doi:10.1289/ehp.1002272