Global Warming Effects

The Clinton administration recently released a report predicting  probable climate changes in the United States as global temperatures continue to rise.  In coming decades the predictions include crop increases in the heartland, increased coastal erosion caused by more frequent and more violent storms plus a steady rise in sea level, summer droughts  and winter floods in the west as well as sweltering summer temperatures in urban environs like New York City. Based on the assumption that global temperatures will rise between 5-10 degrees Fahrenheit by 2100 and carbon dioxide concentrations will continue to rise at their present rate, the report is more pessimistic that that of the Intergovernmental Panel on Climate Change, a United Nations group whose best estimate on warming over the next one hundred years is 3.6-6 F. degrees by 2100.

One of the more serious conclusions of the report is that society will be able to adapt to the changes but many elements of nature, for example, coral reefs and mangrove stands, will not.  These ecosystems will simply be crowded out by human activity.

The report is available on the web at www.nacc.udgcrp.gov.

The report has drawn its share of  criticism. .  Critics point out the  conclusions are a  merger of two greenhouse simulation models that have serious disagreements with each other. For example, one model predicts drought in the southeast, the other increased rainfall.  Many scientists say that only generalized effects can be predicted,.  Local   climatic shifts may be complicated by a number of unforeseen interactions.

In an article in the August 2000 issue of Scientific American, Paul Epstein points out that global warming is already having adverse consequences on world health.  Warmer weather accompanied by a decline in freezing temperatures allows a great many carriers of serious disease to spread beyond their normal boundaries.  Probably the most significant of these is the mosquito which is an intermediate host for the organisms that cause malaria, dengue (aka “breakbone”) fever, yellow fever, encephalitis, and, more recently, Rift fever and west Nile fever.

In an  article in the July issue of Atlantic Monthly, Sarewitz and Pielke argue  that more models and more science will not break the gridlock over what actions we should take to avert the predicted effects of warming but instead deal with the weather problems it may  already be causing. They contend that political action is hostage to not only to the limitations of science to document global warming but to correlating the blame with human activity. Politically, our present policy is to do more research but the upshot of that has been a call for even more research and no concrete action.  The authors suggest a different tack;  work at reducing our vulnerability to extreme weather. This includes both societal changes as well as  our approach to the environment.  This would include practical steps such as reforestation to prevent floods and landslides,  reduced logging to accomplish similar goals, changes in grazing  and agricultural practices, fishing regulations and alike.

The August 2000 issue of Scientific American, in an article by Paul Epstein, points out another hazard of global warming, an increase in tropical diseases.  This, he points out, is well under way.  Malaria and dengue (aka “breakbone”) fever, spread by mosquitoes, are on the increase  in regions where, in past cooler years, they were rare. About 45 percent of the world’s population is now exposed; by 2100, 60 percent will be at risk. Epstien also looks at the West Nile virus, encephalitis, hanta virus and cholera.

01/08/04 19:14