Evaluation of airborne C- and X- band SAR data covering parts of Darbhanga for flood signatures

Abstract

An evaluation of C-(developed at SAC) and X-band (data of opportunity) Airborne SAR (ASAR) data was done for flood signatures. The data was collected over parts of a perennially flood affected area of Darbhanga district located in the Bihar State. This activity is carried out as an R&D effort under the Disaster Management Support Programme (DMSP) at SAC. The ASAR data was critically analyzed for identifying flood features and with an aim to develop it finally as a system dedicated for DMS. The need for such a system is important as many a times there are gaps in satellite coverage over tropical regions for flood damage assessment besides it was observed that the varying flight directions provided additional information as regards the flood signatures. Both the airborne data were available in near synchronous time frame and with VV polarization. A comparison of C-and X-band ASAR showed that the inundated area was estimated better in X-band (62.8 %) as compared to C-(50.2 %) and that the combined data set gave further improvement (71.0 %).