6A.2
Intercomparison of polarimetric radar, profiler and disdrometer observations of tropical precipitation during CAMEX-4/KAMP
Justin T. Walters, University of Alabama, Huntsville, AL; and D. Kim, K. R. Knupp, C. R. Williams, E. N. Anagnostou, and A. Tokay
Intercomparison of Profiler, Polarimetric and Disdrometer Observations of Tropical Precipitation During CAMEX-4/KAMP
During the 2001 Keys Area Microphysics Project (KAMP), a part of the Fourth Convection and Moisture Experiment (CAMEX-4), the Mobile Integrated Profiling System (MIPS), using a 915 MHz profiler, and the X-Band Polarization Radar on Wheels (X-POW) conducted coordinated observations of precipitating systems. Additionally, a disdrometer was operated by NASA Goddard at the MIPS site. This paper will present a case study, from September 10, of passage of a tropical convective line trailed by variable stratiform precipitation. Two topics addressed here are 1) preliminary analyses and intercomparisons of disdrometer measured and profiler and polarimetrically estimated drop size distributions (DSD) and 2) intercomparison of rainfall rate estimators, from the profiler, radar, and disdrometer.
The deployment of a profiler, disdrometer and polarimetric radar has provided different perspectives to analyze raindrop DSDs. The disdrometer will be used to calculate near-ground reflectivity, which can then be used as a calibration tool for the profiler and radar. For the profiler, reflectivity calibration will permit the use of the sans air motion (SAM) model to estimate raindrop DSD, rain rate, mass weighted mean diameter and ambient vertical air motion. Since X-POW operates at an attenuating wavelength, differential propagation phase and specific differential propagation phase will be used to correct reflectivity. Comparison of lowest elevation angles with the disdrometer will allow quantitative assessment of reflectivity corrections. Corrected horizontal reflectivity (ZH) and corrected differential reflectivity (ZDR) will then be used with phase information to estimate raindrop DSDs and rainfall rate. DSDs and rainfall rates measured or estimated from the three platforms will be compared.
Session 6A, tropical cyclone rainfall II
Tuesday, 4 May 2004, 10:15 AM-11:45 AM, Le Jardin Room
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