海平面上升與近代人類活動所造成氣候變遷現象有著緊密關聯，而海面變化尤其對於近岸陸地人口稠密區域造成相當大的威脅。以亞洲而言，孟加拉的恆河三角洲、越南的湄公河三角洲與中國的長江三角洲為首當其衝之處。這些三角洲因為水資源需求與地質脆弱，容易因超抽地下水造成地表變化，當地地表沈陷若與海平面上升現象產生加乘作用，相對海平面上升速率將較預期的增快許多。然而近海陸地在多數全球數值高程模型中未有詳細且準確的高程，導致淹水災害難以評估。因此本計畫擬利用多衛星觀測地表變化，包含利用光學衛星重建內陸與海岸地區高程，同時利用雷達衛星監測地表沉降，針對三處亞洲河口低地研究災害潛勢，以利後續評估海岸脆弱度以及制訂因地制宜的調適策略。 ;Sea-level rise (SLR), widely recognized as one of consequences resulting from anthropogenic climate change, has induced substantial coastal vulnerability in many populated deltas worldwide, such as three densely populated regions in Asia: Bangladesh, Mekong, and Yangtze deltas. The relative SLR (RSLR), combining eustatic/regional SLR with severe land subsidence due to fluvial sediment loading and anthropogenic extraction of ground water, have significantly exacerbate the coastal vulnerability of these deltas. The topographic surfaces of land and ocean have been measured individually worldwide from space, while several global products are available from multiple agencies. However, the accurate link between both spatially varying quantities remains elusive. The uncertain estimates of land deformation and inundation areas, which base on the biased topography and ocean surface models, would eventually lead to an inadequate assessment of coastal vulnerability. Our objective is to improve the understanding of the relative position between ocean and low-lying lands and their interactions that govern coastal vulnerability. The linkage is essential to deciphering the factors to address long-term sustainability in these three populous deltas.
