Flash Drought in CMIP5 Models

Abstract ‘Flash drought’ (FD) describes the rapid onset of drought on sub-seasonal times scales. It is particular interest for agriculture as it can deplete soil moisture crop growth in just a few weeks. To better understand processes causing FD, we evaluate importance evaporative demand and precipitation by comparing three different indices that estimate this hazard using meteorological hydrological parameters from CMIP5 suite models. We apply Standardized Precipitation Index (SPI); Evaporative Demand Drought (EDDI), derived (E 0 ); Stress (ESI), which connects atmospheric conditions measuring ratio actual potential evaporation. The results show moderate-to-strong relationships (r 2 > 0.5) between upper level daily time scales, especially drought-prone regions. find all are able to identify FD top 10-cm layer similar proportion models’ climatologies. However, there significant inter-model spread characteristics FDs identified. This mainly caused an overestimation E , indicating stark differences land surface models coupling individual Of indices, SPI provides highest skill predicting prior or at moisture, while both EDDI ESI significantly lower skill. highlight lack main contributor climate models, with playing secondary role.