New research confirms that temperatures in the lower atmosphere are not behaving as climate models have projected—and are warming far less than expected.
Universally, climate models that are run with increasing atmospheric concentrations of greenhouse gases produce some degree of warming at the earth’ surface, but even more warming above the surface, especially in the layer from 5,000 to 30,000 feet. Models project this warming aloft to be especially strong in the tropical half of the planet (less so for a very small region around the poles). Actual observations of temperature trends in the lower atmosphere, however, don’t confirm these model results, instead showing that warming trends in general decline with altitude.
Why is this important? The atmosphere is an integrated whole, and temperatures aloft are an important determinant of temperatures at the surface. If the models have this wrong upstairs, but right for the area near the surface, they’ve been pretty lucky, or, some might say, pretty “adjusted.”
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