[Previous] | [Session 40] | [Next]
A. A. Simon-Miller (NASA GSFC), B. J. Conrath, P. J. Gierasch (Cornell), G. S. Orton (JPL), R. K. Achterberg (SSAI), B. M. Fisher (JPL), F. M. Flasar (NASA GSFC)
Retrievals run on Cassini Composite Infrared Spectrometer data obtained during the distant Jupiter flyby were used to generate global temperature maps of the planet in the troposphere and stratosphere. Similar retrievals were performed on Voyager 1 IRIS data to yield temperature maps over the same regions, including the first detailed IRIS map of the stratosphere. In both data sets, high latitude troposphere temperatures were retrieved for the first time and meridional gradients support the presence of circumpolar wind jets. Thermal winds were calculated for each data set and show strong vertical wind shears at low latitudes, in balance with the temperature variations.
The temperatures retrieved from the two spacecraft were also compared with yearly ground-based data obtained over the intervening 21 years. Tropospheric temperatures reveal gradual changes at low latitudes, with little seasonal or short term variation (Orton et al. 1994). Stratospheric temperatures show much more complicated behavior over short timescales, consistent with quasi-quadrennial oscillations, as had been noted in prior analyses of shorter intervals of ground-based data (Orton et al. 1991, Friedson 1999). The more recent data sets reveal unexpected temperature changes in the late 1990s, however.
[Previous] | [Session 40] | [Next]
Bulletin of the American Astronomical Society, 35 #4
© 2003. The American Astronomical Soceity.