EDO Standardized Precipitation-Evapotranspiration Index MARSMet, 9-month accumulation period (SPEI-9) (version 1.1.0)

The 9-month Standardized Precipitation-Evapotranspiration Index (SPEI-9) is an indicator used to monitor meteorological drought based on precipitation and reference evapotransipration. Anomalies over 9-month accumulation periods. SPEI-9 serves as a proxy indicator for medium-term impacts, such as reduced stream flow and reservoir storage. The input data for calculating the SPEI-9 is the 10-km interpolated daily data (MARSMet) created and maintained by the EC-JRC Agri4CAST project for the MARS Crop Yield Forecasting System.