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Flash Drought

Drought Map
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Flash Drought Index (FDI) indicates the onset and duration of a flash drought event, such as FDI=1 when the rapid intensification is met for a period of at least two weeks and at the end of this intensification period the drought condition is met (i.e., ESI<-1). The value of the FDI indicates the number of consecutive days these conditions are met. FDI returns to 0 when the drought condition is no longer met. More details on computation of the FDI can be found in Nguyen et al 2021.


The Evaporative Stress Index (ESI) is the standardized anomaly of the actual evapotranspiration to potential evapotranspiration ratio derived from the Bureau of Meteorology's land surface water balance model version 7 (AWRAl-v7) daily outputs. Detailed description of the method can be found in Nguyen et al 2019 .