Impact of anthropogenic climate change on flash drought over southern Africa

“Flash drought” became popular after the unexpected 2012 central USA drought, mainly due to its rapid development, low predictability and devastating impacts on water resources and crop yields. During December-January of 2015/16, there was a severe flash drought characterized by persistent soil moisture deficit and heat waves over southern Africa. In the region, 32 temperature records were broken in South Africa with the highest reached 45°C, and 2015 was recorded as the driest year since 1904. Millions of people suffered from famine, disease and water shortage. This study will investigate the 2015/16 southern African flash drought in the context of a changing climate during 1948-2016, and diagnose the influence of anthropogenic climate change on the flash drought event.

The Variable Infiltration Capacity (VIC) land surface hydrological model, which has been implemented in the Princeton African drought monitoring system, will be used to estimate the change of flash drought during 1948-2016. Daily precipitation and temperature from 30 CMIP5 historical simulations with natural and natural forcing scenarios will be used to drive VIC model to investigate the frequency and geographic distribution of flash drought with or without anthropogenic influences. The Mann-Kendall test and regularized optimal fingerprinting method will be used to detect and attribute the change in flash drought.