Millimeter-Wavelength Radar Observations of Coastal Marine Stratocumulus for Radiation, Cloud Microphysics, and Aerosol Studies

Coastal marine stratocumulus clouds provide unique condition for studying processes important to understanding interactions among aerosols, clouds, drizzle, and radiation. To fully characterize these clouds, the University of Miami 94 GHz Doppler Cloud Radar (UMDCR) was included as a key component of the first deployment of the DOE ARM Mobile Facility (AMF) to a costal location in Pt. Reyes National Park, California. In addition to the UMDCR, the AMF includes a suite of remote sensing systems for further characterizing cloud and boundary layer structures and in situ instruments for near-surface meteorology, radiation, and aerosol characterizations. Measurements from the site started in March 2005 and are planned to continue through mid-September 2005. At the site, the UMDCR was configured to obtain high temporal and spatial resolution (~1s and 30 m respectively) data, continuous monitoring of transmitted power, and recording of full 512-fft point Doppler spectra and Doppler moments. The radar, which has a sensitivity of -47 dBZ, is operated continuously (24/7) and monitored remotely from Miami FL. This paper will present initial radar results obtained during this deployment and will demonstrate the utility of these data for defining the bulk properties of the clouds, retrieving cloud microphysical parameters, and characterizing in-cloud turbulence.