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GPM - IMERG: Drought Indices

Associated Agencies

NASA

The NASA Integrated Multi-satellitE Retrievals for GPM (IMERG) algorithm combines information from the GPM satellite constellation to estimate precipitation over the majority of the Earth's surface.  This algorithm is particularly valuable over the majority of the Earth's surface that lacks precipitation-measuring instruments on the ground.  Now in the latest Version 06 release of IMERG the algorithm fuses the early precipitation estimates collected during the operation of the TRMM satellite (2000 - 2015) with more recent precipitation estimates collected during operation of the GPM satellite (2014 - present).

 

SPI

The Standardized Precipitation Index, or SPI, is a drought index that captures how observed precipitation deviates from the climatological average over a given time period. This global SPI is derived from the GPM-IMERG dataset, using the Climate Engine tool, and includes timescales of 1, 2, 3, 6, 9, and 12 months. The SPI calculation uses a climatology period of 2000-2020 and non-parametric distribution type.

Precipitation Accumulation

Inches of Precipitation
Inches of Precipitation
Inches of Precipitation
Inches of Precipitation

Percent of Normal Precipitation

Percent of Normal Precipitation (%)
100%
Percent of Normal Precipitation (%)
100%
Percent of Normal Precipitation (%)
100%
Percent of Normal Precipitation (%)
100%
Percent of Normal Precipitation (%)
100%
Percent of Normal Precipitation (%)
100%

Access

Data processed via Climate Engine available for download from NOAA/NIDIS