A new and powerful approach to mapping large-scale landslides using InSAR and LiDAR derived DEMs

In recent years, natural disasters occurred more frequently than before mainly due to extreme rainfall arising from global climate change. The Hsiaolin landslide that caused 450 casualties during the 2009 Typhoon Morakot is a typical example known to many people. After Hsiaolin Landslide, Central Geological Survey and Soil and water Conservation Bureau have devoted great efforts to map potential large-scale landslides using LiDAR-derived 1 m DEM. So far, over ten thousands of large-scale landslides have been identified. Considering vulnerability and risks involved, 182 deep-seated landslides have been selected for further landslide hazard mitigation. Additionally, InSAR analysis that can provide mm resolution displacement rate is also employed to help to determine which site needs to be paid more attention with. This paper has selected Dingyuan New Village in Nantou County to illustrate how to use both of LiDAR derived DEMs and the results of Temporarily Coherent Point SAR Interferometry (TCP-InSAR) to locate large-scale landslides.