Characteristics of Cb with waterspout over Ladoga Lake derived from remote measurements
A.A. Sin'kevich, V.B. Popov, Yu.P. Mikhailovskii, M.L. Toropova, Yu.A. Dovgalyuk, N.E. Veremei, D.S. Starykh
The Voeikov Main Geophysical Observatory, St.Petersburg, Russia
Keywords: водяной смерч, поляризационный радиолокатор, алгоритм классификации гидрометеоров, восходящие потоки, индексы неустойчивости, частота молний, waterspout, polarimetric radar, hydrometeor classification algorithm, updraft, instability indices, lightning frequency
Abstract
Characteristics of the thunderstorm with a waterspout over Ladoga Lake obtained with the help of C-band radar, lightning detection system, and radiosonde data are studied. The analysis of instability indices shows low and moderate probability of developing intensive convective processes. The hydrometeor classification and the updraft identification algorithms are used for the first time for the DMRL-C radar and are based on processing of polarization measurements. These algorithms made it possible to detect the appearance of big ice particles when lightning began and to extended updraft associated with the waterspout. The correlation analysis of the frequency of lightning and cloud characteristics, obtained by radar, was carried out. It showed the closest correlation of the frequency with the number of big ice particles, characterized by supercooled part of the cloud (above the 0 °C level) with the reflectivity higher than 50 dBZ.
|
