Wednesday, 5 May 2004
Improving Hurricane Intensity Forecasts by Combining Microwave Imagery with the SHIPS Model
Richelieu Room (Deauville Beach Resort)
Microwave satellite imagery collected from the Special Sensor Microwave/Imager (SSM/I) and TRMM Microwave Imager (TMI) sensors for all tropical cyclones in the Atlantic basin between 1996 and 2002 are combined with the training data from the operational Statistical Hurricane Intensity Prediction Scheme (SHIPS) model to produce a combined environmental, microwave satellite hurricane intensity model (SHIPS-MI). Microwave bands for which data are readily available include 19 Ghz, 37 Ghz, and 85 Ghz that roughly correspond to rainfall, water vapor, and graupel signatures all of which have some association with cyclone intensity. Various combinations of SHIPS predictors and microwave data revealed that vertically polarized 19 Ghz brightness temperature information within 100 km of a storm center proved to be the most useful addition to the basic SHIPS model. A comparison of the operational SHIPS and the best SHIPS-MI showed that the microwave information decreases absolute forecast intensity errors 0.5 kt or more depending on forecast time. Further enhancement of the SHIPS-MI model is underway using more rigorous modeling techniques and additional microwave derived predictors (e.g. an eye-presence and strength predictor based upon 85 Ghz data).
Supplementary URL: