THE HURRICANE-CUSTOMIZED EXTENSION OF THE VAD (HEVAD) METHOD: HURRICANE WIND ESTIMATION IN THE LOWER TROPOSPHERE

摘要

This paper presents a new single-Doppler radar analysis method that estimates the earth-relative wind field of hurricanes in the Lower Troposphere (LT -altitude ≤ 3 km). Other methods currently in use include the GBVTD (Lee et al., 1999) and TREC (Tuttle and Gall, 1999) methods. The GBVTD method estimates the storm-relative wind field in hurricanes and thus requires extraneous information about the mean flow across the hurricane in order to obtain earth-relative winds for hurricane forecasting purposes. The TREC method also estimates the earth-relative wind field. However, as with all single-Doppler analysis methods, violations of the underlying assumptions made about the wind field bias the results either in certain regions or certain situations. The GBVTD and TREC methods are most accurate in the regions near and far from the hurricane's core, respectively. It is hoped that the current approach will bridge the gap of information in the intermediate region, and perhaps provide mean flow estimates to the GBVTD method so that a complete picture of the earth-relative wind field can be delivered to forecasters.