Cloud structures observed by an airborne radar

Prof. Gabor Vali

Dept of Atmospheric Sciences, University of Wyoming

Airborne radars put into use over the last decade are beginning to fill in the gap between observations provided by in situ sensors mounted on aircraft and the depictions of clouds derived from ground based radars. As could have been expected, these airborne radars are revealing structures of great complexity, which pose new challenges to our thinking about cloud processes. Non-linearities in the processes of nucleation and hydrometeor interactions indicate that the observed fine-scale structures may be of great importance.

The 95 GHz radar mounted on the University of Wyoming King Air aircraft has been in operation since 1992. Studies have been made with this radar of small cumulii, marine stratus, mountain wave clouds, and of deep stratiform clouds. Reflectivity, velocity and polarimetric measurements are obtained. In the first part of the talk, examples of various observations will be used to demonstrate cloud structures, many of them quite unexpected.

The second part of the talk will focus on marine stratus. In situ and radar measurements are used to examine questions related to the evolution of drizzle, entrainment and cloud structure in general.