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Droughts, increasingly intensified by human-induced climate change, pose growing threats to society. Thus, enhancing our capabilities to monitor drought occurrence and intensity is crucial. Here, we present a new dataset of drought indices derived from the 5th generation ECMWF reanalysis system (ERA5), which offers long-term monitoring of the global climate in both deterministic and probabilistic forms — hereafter referred to as ERA5–Drought. Produced by ECMWF, this global dataset is freely accessible through the ECMWF Data Store. To date, it entails two of the most prominent drought indices: the Standardized Precipitation Index (SPI) and the Standardized Precipitation Evapotranspiration Index (SPEI). Both indices are calculated over a range of accumulation periods from 1 month to 4 years and are available for the full ERA5 climatology from 1940 to today. In addition, data that rates the quality of these drought indices is provided. The ERA5–Drought data set serves as a valuable tool for environmental agencies and supports sectors such as agriculture and water management, thus contributing to efforts that monitor water and food insecurity.  

A full description of the data set and usage notes can be found in:

Keune, J., Di Giuseppe, F., Barnard, C., Damasio da Costa, E. and Wetterhall, F.: ERA5–Drought: Global drought indices based on ECMWF reanalysis. Scientific Data12, 616 (2025). https://doi.org/10.1038/s41597-025-04896-y

If you use the dataset, please acknowledge it by citing

this publication. This helps demonstrate the usefulness of the resource and supports its continued availability.

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