Flood hazard assessment in Bangladesh using NOAA AVHRR data with geographical information system

Flooded area and flood hazard assessment in Bangladesh were evaluated using remote sensing (RS) data with the geographical information system (GIS). I mage data from the National Oceanographic and Atmospheric Administration (N OAA) Advanced Very High Resolution Radiometer (AVHRR) were used to analyse Bangladesh's historical flood event of 1988, which sets a hundred-year reco rd for the inundated areas, with severe damage occurring throughout this re gion. Cloudy skies often occur during big floods, and visible and infrared rays observed by the NOAA AVHRR cannot penetrate cloud cover. We therefore proposed a new algorithm for classifying cloud covered pixels into water or non-water categories. In order to estimate the flooded area accurately, th e images taken during the flood and dry season which were classified into w ater and non-water categories were superimposed. A new flood hazard map, cr eated from the land cover category and elevation height data which were ran ked by flood affected frequency, can be used to evaluate flood risk using o nly RS data and elevation height data. Copyright (C) 2000 John Wiley & Sons , Ltd.