Monday, July 26, 2004


"Every climate model that is run with increasing atmospheric concentrations of greenhouse gases produces some degree of warming at earth's surface and even greater warming above the surface, especially in the atmospheric layer between 5,000 to 30,000 feet in altitude (the troposphere). Models calculate this warming to be especially strong in the tropical half of the planet and weaker in a very small region around both poles.

Observations of real world temperature trends in the lower atmosphere don't confirm these model results and instead show that, generally, warming trends decline with altitude.

Why is this important? The atmosphere is an integrated whole. Temperature aloft is an important determinant of temperature at the surface. If the models have the "upstairs" wrong but have it right "downstairs" in the area near the surface, they've been pretty lucky. Some might say, pretty "adjusted."

The discrepancy between models and observations is the crux of one of the major arguments against the models and over reliance on them to anticipate future climate. If the models can't accurately portray present observations, they cannot be relied upon to predict the future.

The hypothesis that models continue to get it wrong is strongly supported by results from a research effort led by The University of Rochester's David Douglass and published in a pair of articles in Geophysical Research Letters (online on July 9, 2004). Two other scientists involved in the effort were Patrick Michaels and Paul Knappenberger, chief editor and technical supervisor of World Climate Alerts"......

In sum, the results of research presented in Douglass's two papers provide strong evidence for three important points:

1) The discrepancy between temperature trends measured at the earth's surface and those measured in the earth's lower atmosphere is real.

2) A large part of this discrepancy likely is caused by local, non-climatic influences on surface thermometers not by stratospheric contamination of the lower tropospheric data.

3) Climate models that include observed changes to known climate forcing agents (both natural and anthropogenic) are unable to replicate the observed behavior of the temperatures in the lower atmosphere. Furthermore, if local, non-climatic influences are largely responsible for the surface temperature trends, then the climate models are getting the surface trends right for the wrong reasons - indicating their failure at that level as well.

Such findings should give pause to anyone who relies on climate model output to inform their decision-making."

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