Many thanks are given to Sun Wong, Kenneth Bowman, Paquita Zuidema, and Eric Fetzer for their advice and guidance. This work was supported by the NASA Earth System Science Fellowship. AIRS data were obtained from the Goddard Space Flight Center’s Data and Information Services Center (DISC). NCEP reanalysis-derived data were provided by the NOAA/OAR/ESRL PSD of Boulder, Colorado, from their Web site (http://www.cdc.noaa.gov/).
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