Cloud and Precipitation Studies Using a Millimeter Wavelength Doppler Radar

University Of Miami, Coral Gables FL

Investigators

Abstract

The objectives of this research are to advance the understanding of cloud development and precipitation formation and to provide observations that can be used for evaluating large-eddy simulations of air flow and mixing processes in clouds. The work is based on observations using ground-based remote sensing instruments consisting of a vertically-pointing 94 GHz (3.2 mm wavelength) radar, a UHF wind-profiling radar, and a newly built vertically-pointing X-band (3.2 cm wavelength) radar. Together, these radars enable the measurement of vertical motions of both the air and the raindrops in clouds. The fall speed of the drops relative to the air can be determined, enabling the estimation of the drop-size distribution. The main site of the experiments is a field station at Virginia Key, although the equipment will be installed on a 20-ft trailer to enable observations from other locations. Observations will be used to document the structure of fair-weather cumulus clouds as well as the relations between precipitation development and vertical air motions in clouds producing heavy rain. The work contributes to precipitation physics by direct observation and to cloud modeling by providing the data needed for validating numerical simulations.