Scientists Still Baffled by Surface- Atmosphere Discrepancy
A new study in the September 2002 issue of the Journal of Climate takes another look at the discrepancy in temperature trends between the surface, measured by ground-based thermometers, and the atmosphere (more specifically the troposphere), measured by satellite-borne instruments, and concludes that we dont know why there is a discrepancy.
The temperature differential between the surface and the atmosphere is known as the lapse rate. From 1964 to 1979 the lapse rate decreased, meaning that surface and atmospheric temperatures were converging. However, beginning in 1980 the lapse rate began to increase and has continued to do so until the present time. Much of the winter-to-winter lapse rate variability in the high latitudes is dynamically induced, according to the study, but most of the change in lapse rate is over the lower latitudes or tropics.
The researchers, Gabriele C. Hegerl of Duke University and John M. Wallace of the University of Washington, attempted to account for this change by comparing the pattern to El Nio southern oscillation and other factors, but found that, “Trends in these patterns can account for only a small fraction of the observed trend in lapse rate.”
The researchers then ran the data through a climate model, both a control run and a run with greenhouse gas and aerosol forcings, which did a decent job of simulating short-term, monthly changes in lapse rate, but failed to simulate decadal scale changes. The model shows a tighter long-term coupling between the surface and atmospheric temperatures than is observed in nature. As this study shows, our understanding of heat transfer between the surface and atmosphere is still incomplete, and until this problem is resolved there is little hope that climate models can tell us anything about what the climate may be like in 10, 50 or 100 years.
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- The September 2002 issue of The Washington Monthly ran an article reminiscent of the “ozone hole over Kennebunkport” flap under Bush I about the possible effects of global warming on President George W. Bushs ranch in Crawford, Texas.
The article begins with an account of British Prime Minister Tony Blairs visit to the Bush ranch for a meeting with the “cowboy president.” President Bushs plans to take Blair on a tour of the ranch were ruined by severe thunderstorms and golf-ball-sized hail. The article fingers global warming as the culprit. “But that possibility apparently seemed as remote to Bush as the likelihood that the storm was a sign from God,” it said.
Theres a good reason why this twaddle may not have crossed President Bushs mind. It turns out that, according to data from the United States Historical Climatology Network, its getting cooler around Crawford. The nearest long-term temperature station to the Bush ranch is in Temple, Texas, 34 miles south of Crawford. It shows a cooling trend since 1890, and since 1920 the yearly average temperature has fallen by well over 2 degrees Celsius.
Announcements
The Cooler Heads Coalition will hold a congressional and media briefing by Professor Richard S. Lindzen of MIT on September 30 from noon to 1:30 PM in Room 345 of the Cannon House Office Building. Lunch will be provided. Reservations are required. Those wishing to attend should e-mail their name, affiliation, and phone number to mebell@cei.org or telephone Myron Ebell at (202) 331-1010, ext. 216. Dr. Lindzen will be speaking “On the meaning of global warming claims.”