PHASEARRAY

CLASIC - 9.4 GHz Phase Array Radar

8 June 2007 - 30 June 2007

Lead Scientist: Pavlos Kollias

Observatory: SGP

Land surface inhomogeneities affect the temporal and spatial evolution of cumulus convection. On the other hand, developed cloudiness affect the surface radiation budget and precipitation fall out alters the soil moisture. In turn, these changes in the surface feedback in the cumulus clouds development. The SGP Cloud LAnd Surface Interaction Campaign (CLASIC) conducted June 2007 addressed these scientific issues. Short-range (50 km) weather radars operating at 9.4-GHz are often used to provide continuous mapping of the spatial distribution of precipitation over a large domain. The Center for Interdisciplinary Remotely-Piloted Aircraft Studies 9.4-GHz phased-array radar was deployed at the SGP during the CLASIC. Using multiple beams and frequencies that are controlled electronically, phased array radar reduces the volume scan time from minutes to seconds, provide a unique mapping of precipitation. We participated for the entire IOP (8-30 June). The radar provided comprehensive mapping of the 3D structure of shallow and deep precipitation on a 50x50 km domain around the SGP. The mapping of precipitation over such large domain was used to evaluate the meso-scale structure of cumulus convection, its organization, diurnal cycle and variability and it’s relevant to land surface processes and properties. Comparisons with the ARM millimeter-wavelength vertically pointing cloud radars and disdrometer were used to calibrate the radar and develop a Z-R relationship.