Observation impact of dropsonde data in the ECMWF model during T-PARC 2008

• During the THORPEX-Pacific Asian Regional Campaign (T-PARC) in 2008 dropsondes were released for the purpose of targeting typhoon systems in the West Pacific • Joint missions were conducted, with simultaneous dropsonde observations in the typhoon center and core, the typhoon vicinity and in remote sensitive areas by four aircraft • Data denial studies are performed to evaluate the impact of the dropsondes for typhoon track forecasting with the ECMWF global model • Dropsondes are separated into observations located in the typhoon vicinity ('CeObs'), next to the center and core of the typhoon ('CeObs2'), and in remote sensitive areas ('ReObs') → impact of different subsets of observation