1 11A.3 THE IMPACT OF DROPSONDE DATA FROM DOTSTAR ON TROPICAL CYCLONE TRACK FORECASTING

Abstract 1 DOTSTAR, short for Dropwindsonde Observations for Typhoon Surveillance near the Taiwan Region, is an international research program conducted by meteorologists in Taiwan partnered with scientists at the Hurricane Research Division (HRD) and the National Centers for Environmental Prediction (NCEP) of the National Oceanic and Atmospheric Administration (NOAA). The DOTSTAR research team launched their typhoon surveillance in 2003. During 2004, 10 missions for 8 typhoons were conducted successfully with 155 dropwindsondes deployed. In this study, the impact of the dropwindsonde data on tropical cyclone track forecasts has been evaluated with five models (4 operational and 1 research). All models, except the Geophysical Fluid Dynamics Laboratory (GFDL) hurricane model, show positive impact the dropwindsonde data have on tropical cyclone track forecasts. During the first 72 h, the mean track error reductions in the NCEP Global Forecast Syste