QuickSCAT's SeaWinds facilitates early identification of tropical depressions in 1999 hurricane season

Abstract

Far from land and surface ship observations, most tropical depressions are identified by examining images from geostationary satellites for the presence of rotation of the convective cloud masses. During the 1999 hurricane season, surface wind vectors obtained by the Sea Winds scatterometer on the QuickSCAT satelite for the tropical Atlantic and Caribbean Sea were examined to test hypothesis that developing tropical depressions (TDs) could be observed with this satelite sensor, before identification by the traditional means. QuickSCAT was able to detect the presence of closed circulation in the surface winds before the systems were designated as depressions. The satellite's unprecedented large swath width of 1800 km allows twice a day observation of most of the tropical oceans. Sea Winds data can therefore, provide valuable guidance that are an important addition to the tools available to the tropical cyclone forecasting community.