Flash drought monitoring of agriculture systems using multi-source remote sensing and soil moisture data fusion in East Asia

East Asia is one of the most vulnerable regions to climate change and disaster. Among which, drought disaster is the most attractive extreme events and has caused numerous economic losses. It is critical to investigate how drought affects this region, and more importantly, how can we adapt to this kind of drought shock under climate change. Recent large precipitation deficits or increases in evaporative demand derive from unusual climate conditions. If precipitation deficits are accompanied by above average evaporative demand such as higher temperatures, increased vapor pressure deficit, and surface insolation, rapid drought intensification can occur. This type of drought is usually termed "flash drought", which has been used to describe an additional type of drought with the characteristic of rapid onset and high intensification. Flash drought events accelerate negative outcomes experienced at the land surface via rapid depletion of available soil water and excessive moisture stress on vegetation. This research aims to select agriculture as the hazard-bearing body, and explore the response of agriculture to drought shocks in East Asia. This will determine agriculture responses (i.e., yield loss) under flash drought events in East Asia, and then new time-varied index will be proposed to quantify drought stress on agriculture. Based on a global remote sensing-based reanalysis dataset, we identify flash droughts across China and Korea by focusing on the depletion rate of soil moisture percentile to understand climate change on its agriculture systems, and shed lights on flash drought shock adaptations for a resilient agriculture.