Rainband Feature Tracking for Wind Speeds around Typhoon Eyes Using Multiple Sensors

摘要

In this study, five typhoon cases observed by quasi-concurrent satellite-based Synthetic Aperture Radar (SAR) and Moderate Resolution Imaging Spectroradiometer (MODIS) data, and one of the cases also by ground-based Doppler radar observations have been studied. The rainband features around typhoon eyes are first delineated using wavelet analysis, and then the wind speeds are estimated by feature tracking using quasi-concurrent multi-sensor images. It was found that the resulting wind speeds are reasonable compared with the maximum wind speed reported by the Joint Typhoon Warning Center (JTWC), which accounts for the radial dependence of wind speed using the Rankine combined vortex approximation. In a specific case, with the aid of Doppler radar near the coast, wind speed estimation based on the multi-sensor also shows consistent results. This study demonstrates that the local wind distribution of cyclonic winds around typhoon eyes at different radial distances from the typhoon centers may be derived from rainband feature tracking using quasi-concurrent multi-sensor images. This technique may offer useful wind information for typhoon simulations and forecasting.