Joint EOL/TiiMES seminar presented by Anthony Illingsworth, Department of Meteorology, University of Reading, UK.
It will be difficult to use the polarization parameters on Nexrad for rain rates below 10mm/hr because the signals are small and noisy. For example, the noise on the differential reflectivity (ZDR) at each gate appears to about 0.5dB and frequently has an unphysical negative value. However, we have found that by looking at the distribution of the Z and the ZDR signals over a 5km square area we are able to derive the raindrop concentration, Nw, quite accurately and hence compute the value of 'a' which should be used in the empirical Z = a R^1.5 relationship over each 5km square area. We find remarkable consistency with the Nw derived from a coincident profiler thus confirming the precision and validity of the Z/ZDR technique. Possible implementation in the operational NEXRAD network will be discussed.
Friday, August 4 at 3:00pm in FL2-1001 (refreshments at 2:30pm)
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