LONG-TERM FLOOD DAMAGE BY PERMAFROST DEGRADATION IN SIBERIA

In the far North of Siberia, air temperature is increasing due to global warming. The warmer-than-normal air temperature thawed permafrost. Flood was caused when a large amount of permafrost thawed. Objectives are to monitor permafrost degradation using microwave remote sensing, to demonstrate spatio-temporal patterns of flood, and to understand flood-generating mechanism in order to manage flood risk. After ice wedge melting due to the increased air temperature, the melting water gushed from the ground. Then, the melting water flowed into a nearby river, leading to floods. Ground subsidence by permafrost degradation was measured using DInSAR of ALOS/PALSAR. Flood damages were quite different by location. In downstream area around Andryushkino, flood damage continued for two years. The flood water flowed slowly toward the north, because landscape in this area is almost flat without slope. Therefore, the local people who lived in Andryushkino suffered flood for a long time.