Investigation of Two Microburst Producing Storms Using a Microburst RecognitionAlgorithm

摘要

A review of the history of the microburst, complete with current achievements, isgiven. Two microbursts are investigated and associated precursors were extracted with the use of a microburst recognition algorithm. The precursors were then used to determine the forcing mechanisms for the microbursts. The structure of the microbursts and the timing of the precursors were compared and contrasted with each other and also with a moderate reflectively model, and differences are discussed. One microburst was initiated by a misocyclone which created vertical pressure gradients, while the other microburst was initiated by precipitation drag. All five precursors were detected in both events. It was discovered that several improvements could be made upon the microburst recognition algorithm. The algorithms main difficulty stemmed from the fact that it was tuned to high reflectivity events, and thus had difficulty with the two microbursts which were of a lower reflectivity class. It was pointed out that this could be solved by incorporating the moderate reflectivity model into the algorithm complete with a subroutine which enables the algorithm to determine the reflectivity class of microbursts.