Influence of water ice clouds on nighttime tropical temperature structure as seen by the Mars Climate Sounder

An analysis of nighttime temperature and water ice cloud extinction profiles from the Mars Climate Sounder aboard the Mars Reconnaissance Orbiter provides evidence for the close relationship between tropical temperature structure and water ice clouds. The tropical temperature structure that evolves over the spring and summer seasons is closely coupled to the waxing and waning of tropical cloud activity. The presence of strong elevated nighttime temperature inversions in the Tharsis region is a robust feature of the equatorial atmosphere during the L-s=0-135 degrees season, with little interannual variation seen in the three Mars years examined. Mars global circulation model simulations imply that cloud radiative forcing plays a dominant role in the seasonal modulation of the observed longitude distribution of warm and cold anomalies in surface and low-altitude air temperatures, respectively.