Response and recovery of terrestrial ecosystem productivity to flash drought over China under climate change

The increasing drought with rapid onset in a warming climate arouses wide concerns due to its enormous impacts on the terrestrial ecosystem. Despite the duration of flash drought is relatively short ranging from several weeks to months, its legacy effects on the terrestrial ecosystem may remain even after flash drought. Here we use remote sensing observations of Solar-Induced chlorophyll Fluorescence (SIF) and Gross Primary Productivity (GPP) and a land surface model to investigate the negative impacts and legacy effects of flash drought on terrestrial ecosystem productivity. The decline and recovery in observed and modeled terrestrial ecosystem productivity caused by flash drought are more rapid over drier regions, showing lower drought resistance and higher drought recovery. For wetter regions, GPP and SIF over wetter regions show higher drought resistance, whereas they are still lower within 15 days after flash drought compared with their pre-drought level. The resistance of terrestrial ecosystem productivity shows a significant increasing trend during recent decades, which is possibly related to the increased vegetation growth. The legacy effects of flash drought over wetter regions highlight the importance of drought monitoring and forecasting over humid or semi-humid regions