FLOOD MONITORING OF MEKONG RIVER DELTA, VIETNAM USING ERS SAR DATA

Successful launches of space borne high resolution microwave imaging radars in recent years added a new dimension of remote sensing technology to observe the Earth. With its all-weather and day-night time imaging capability, It has an interesting potential in the study of hydrological processes, especially in the tropical countries like Vietnam, where there is a limitation from using traditional optical imagery. Flood monitoring using SAR imagery has proven to be very successful. This study presented preliminary results of flood investigation in the Mekong River Delta (MKD), Vietnam based on analysis and interpretation of some ERS SAR PRI data, especially to monitor of changes from temporal flooding situations during the rainy season. A case study of flood monitoring in 1996 has been investigated. As a well known that in Vietnam, 1996 brought most serious damages from flooding into both of human and property. Five ERS-2 SAR PRI scenes of upper part of MKD acquired between June 1996 and February 1997 were processed into a set of multi -temporal images for interpretation and analysis, based on the knowledge in the changes of radar backscatter from surface, due to surface roughness, soil moisture and vegetation cover. The multi-temporal image revealed high variation in vegetation and soil surface roughness both in time and space, especially during the rainy season. A preliminary assessment of flood damages was focused to estimate affected paddy fields in the region.