Jovian Tropospheric Horizontal and Vertical Temperature Structure During the Galileo G1 Orbit

B.M. Fisher tex2html_wrap_inline11 , G.S. Orton, M. Ressler, S. Hinkley tex2html_wrap_inline13 (JPL,Caltech)

We observed Jupiter at 11 thermal infrared wavelengths from 7.85 tex2html_wrap_inline15 m to 24.5 tex2html_wrap_inline15 m from June 26-July 1, 1996 using the MIRLIN camera at the NASA IRTF. The observations were made in support of the Galileo Ganymede-1 orbit to provide a global perspective to compliment the high-resolution, limited-area spacecraft observations. Our wavelength coverage allows for sounding of the tropospheric temperatures at pressures of approximately 100-500 mbar. The sounding results in maps of temperature as a function of latitude, longitude, and pressure. Good weather during the observation period allowed for complete planet coverage. We apply the thermal wind equation for geostrophic conditions to find latitudinal and longitudinal wind shears as a function of pressure and location. Preliminary results have shown evidence for a counter-rotating region in the center of the Great Red Spot at the 250 mbar level. Thermal wind shears are examined in detail at the latitudes of the 5 tex2html_wrap_inline15 m hot spots, the North Equatorial Belt (NEB) and around the southern-hemisphere classical white ovals. Considerable longitudinal structure is observed in Jupiter's NEB. The vertical temperature structure of these features is examined for evidence vertical shear in the rotation rates. Temporal changes on the time scale of a few days are examined.

tex2html_wrap_inline11 NASA/NRC Resident Research Associate
tex2html_wrap_inline13 Caltech Summer Undergraduate Research Fellow