Is this the same as moving the entire state one degree southwards?
Reporting in today's issue of Science,
researchers at the universities of Washington and Utah examined
satellite data from the past 27 years and discovered that the jets have
been wandering. During this time, the subtropical jets have moved as
much as 1° of latitude, or 112 kilometers, away from the equator and
toward the poles. The researchers also found what they think might be
causing the migration: The troposphere--the layer of atmosphere
reaching from the surface to an altitude of about 12 kilometers--has
warmed faster than the rest of the atmosphere over the subtropics in
bands centering about 30° north and south of the equator.
Simultaneously, the stratosphere--which overlays the troposphere,
extending to 50 kilometers--has been cooling.
Abstract here:
http://www.sciencemag.org/cgi/content/abstract/312/5777/1179
Enhanced Mid-Latitude Tropospheric Warming in Satellite Measurements
The spatial distribution of tropospheric and stratospheric temperature trends for 1979 to 2005 was examined, based on radiances from satellite-borne microwave sounding units that were processed with state-of-the-art retrieval algorithms. We found that relative to the global-mean trends of the respective layers, both hemispheres have experienced enhanced tropospheric warming and stratospheric cooling in the 15 to 45° latitude belt, which is a pattern indicative of a widening of the tropical circulation and a poleward shift of the tropospheric jet streams and their associated subtropical dry zones. This distinctive spatial pattern in the trends appears to be a robust feature of this 27-year record.
1 Department of Atmospheric Sciences, University of Washington, Seattle, WA 98195, USA.
2 College of Atmospheric Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China.
3 Department of Meteorology, University of Utah, 135 S 1460 E, Room 819 (WBB), Salt Lake City, UT 84112-0110, USA.
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