摘要：This article discusses the near real-time (NRT) satellite mapping activities in response to the recent Gorkha earthquake in Nepal by UNSW as well as other institutions around the globe. This study demonstrates that data from current SAR satellites can already be processed and delivered in near real-time to support post-disaster response and emergency management. Three ALOS-2 PALSAR-2 interferometric pairs were used by the GEOS team at UNSW (2 Stripmap pairs and 1 ScanSAR pair) to deliver a suite of satellite remote sensing products, such as the differential interferometric SAR (DInSAR) interferogram, DInSAR ground displacement map, contour map of ground deformation, horizontal ground displacement based on the pixel offset tracking analysis, and damage map based on coherence difference analysis. This study shows that the mapping products can be released 6–8 hours after the post-event image is acquired using international ground receiving stations, with the direct mapping activities such as DInSAR and GIS processing typically taking 3–4 hours only. This study also discusses the urgent need for internationally coordinated development and deployment of SAR satellite constellations in order to greatly reduce the latency in NRT mapping of disasters, which will benefit a range of other satellite remote sensing applications as well. Moreover, it is suggested that the near real-time responses be coordinated across the globe in order to improve the effectiveness of rapid disaster mapping in order to mitigate the effects of earthquakes and other natural disasters.
