STUDY OF A WINTER MONSOON FRONT AND A SQUALL LINE OVER THE SOUTH CHINA SEA BY SYNERGETIC USE OF SYNTHETIC APERTURE AND WEATHER RADAR DATA

摘要

Synthetic aperture radar (SAR) images acquired by thernAdvanced Synthetic Aperture Radar (ASAR) onboardrnthe European Envisat satellite and weather radar imagesrnof the Hong Kong Observatory (HKO) are used to studyrna winter monsoon front and a squall line over the SouthrnChina Sea (SCS). The atmospheric front was generatedrnby a freshening of the northeast monsoon caused by thernmerging of two high pressure areas over the ChinesernContinent. The high-resolution SAR image reveals finescalernstructures of the front which cannot be obtained byrnother spaceborne sensors. This front is furtherrninvestigated by using other satellite data and byrncomparing the observational data with model data.rnSquall lines are lines of organized convective rain cellsrnaccompanied by wind shear and high wind gusts. It isrnshown that the synergetic use of high-resolution SARrnand weather radar data provides a comprehensive viewrnof the three-dimensional wind flow associated with thernsquall line.