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Global Gridded Standardized Precipitation Index (SPI) from CMORPH Daily

Associated Agencies

National Oceanic and Atmospheric Administration's (NOAA) Climate Prediction Center (CPC)

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 NOAA CMORPH dataset, using the Climate Engine tool, and includes timescales of 1, 2, 3, 6, 9 and 12 months.

The NOAA CMORPH precipitation dataset is a gridded dataset derived from combining numerous microwave-based estimates from low orbiter satellites.  The dataset is also archived and managed through the NOAA Climate Data Record program at NOAA's National Centers for Environmental Information (NCEI).

Interactive Map: Standardized Precipitation Index (SPI)

Dry Conditions
Wet Conditions
Dry Conditions
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HOW TO

How to use this site:

  • Datasets are in GeoTIFF, readable by GIS software and many meteorological tools.

ACCESS

SPI from CMORPH in GeoTIFF: available for download from NOAA/NIDIS 

Related Publications

Joyce, R. J., J. E. Janowiak, P. A. Arkin, and P. Xie, 2004: CMORPH: A method that produces global precipitation estimates from passive microwave and infrared data at high spatial and temporal resolution.. J. Hydromet., 5, 487-503.   https://ftp.cpc.ncep.noaa.gov/precip.orig/CMORPH_V1.0/REF/Joyce_et_al_2004_JHM_CMORPHP.pdf

Guttman, N. B., 1999: Accepting the standardized precipitation index: A calculation algorithm. J. Amer. Water Resour. Assoc., 35, 311–322, https://doi.org/10.1111/j.1752-1688.1999.tb03592.x.

Wu, H., M. J. Hayes, D. A. Wilhite, and M. D. Svoboda, 2005: The effect of length of record on the standardized precipitation index. Int. J. Climatol., 25, 505–520, https://doi.org/10.1002/joc.1142.

Wu, H., M. D. Svoboda, M. J. Hayes, D. A. Wilhite, and F. Wen, 2007: Appropriate application of the standardized precipitation index in arid locations and dry seasons. Int. J. Climatol., 27, 65–79, https://doi.org/10.1002/joc.1371.

Cumbie-Ward, R. V., and R. P. Boyles, 2016: Evaluation of a high-resolution SPI for monitoring local drought severity. J. Appl. Meteor. Climatol., 55, 2247–2262, https://doi.org/10.1175/JAMC-D-16-0106.1.

Vose, R. S., and et al, 2014a: NOAA’s Gridded Climate Divisional Dataset (CLIMDIV). NOAA National Climatic Data Center, accessed 4 June 2018, https://doi.org/10.7289/V5M32STR.