Atmospheric Chemistry and Physics www.atmos-chem-phys.net 1680-7316 1680-7324 10 6 2010 10.5194/acp-10-2643-2010 http://www.atmos-chem-phys.net/10/2643/2010/ http://www.atmos-chem-phys.net/10/2643/2010/acp-10-2643-2010.html http://www.atmos-chem-phys.net/10/2643/2010/acp-10-2643-2010.pdf 2643 2653 2010-03-18 On the seasonal dependence of tropical lower-stratospheric temperature trends Q. Fu qfu@atmos.washington.edu S. Solomon P. Lin Department of Atmospheric Sciences, University of Washington, Seattle, WA, USA College of Atmospheric Sciences, Lanzhou University, Lanzhou 730000, China Chemical Science Division, Earth System Research Laboratory, NOAA, Boulder, CO, USA This study examines the seasonality of tropical lower-stratospheric temperature trends using the Microwave Sounding Unit lower-stratospheric channel (<i>T</i>₄) for 1980–2008. 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