Gobal Precipitation Climatology Project (GPCP) Version 2.1

SOURCE: G.J. Huffman, D.T. Bolvin, and R.F. Adler, working in the Laboratory for Atmospheres, NASA Goddard Space Flight Center, Code 613.1, Greenbelt, Maryland, USA, as the GPCP Merge Development Centre.

DATA DESCRIPTION: GPCP V2.1 documentation


GRID: Global - 2.5 x 2.5 degree grid


TIMES: 12 values per year

CURRENT HOLDINGS: Jan 1979 - Dec 2009


Description Name Units
Monthly satellite-guage precipitation PREC mm day-1
Absolute error ERROR mm day-1



  • GPCP_V21.yyyy.nc
  • GPCP_V21.esg.yyyy.nc
  • V21_GPCP.1979-2009.nc
  • V21_GPCP.esp.1979-2009.nc

where "yyyy" is the 4-digit year and "esg" represents files containing absolute error.

Update History:

  • /CA/GPCP/MONTHLY/V21_GPCP.1979-2009.nc


  • Huffman, G.J., R.F. Adler, D.T. Bolvin, G. Gu, 2009: Improving the global precipitation record: GPCP Version 2.1. Geophys. Res. Lett. submitted.
  • Adler, R. F., G. J. Huffman, A. Chang, R. Ferraro, P. Xie, J. Janowiak, B. Rudolf, U. Schneider, S. Curtis, D. Bolvin, A. Gruber, J. Susskind, P. Arkin, E.J. Nelkin, 2003: The Version 2.1 Global Precipitation Climatology Project (GPCP) Monthly Precipitation Analysis (1979-Present). J Hydrometeor., 4(6), 1147-1167.
  • Adler, Robert F., George J. Huffman, David T. Bolvin, Scott Curtis, Eric J. Nelkin, 2000: Tropical Rainfall Distributions Determined Using TRMM Combined with Other Satellite and Rain Gauge Information. Journal of Applied Meteorology: Vol. 39, No. 12, pp. 2007-2023.
  • Huffman, George J., Robert F. Adler, Mark M. Morrissey, David T. Bolvin, Scott Curtis, Robert Joyce, Brad McGavock, Joel Susskind, 2001: Global Precipitation at One-Degree Daily Resolution from Multisatellite Observations. Journal of Hydrometeorology: Vol. 2, No. 1, pp. 36-50.
  • Huffman, G.J., 1997: Estimates of root-mean-square random error contained in finite sets of estimated precipitation. J. Appl. Meteor., 36, 1191-1201.
  • Huffman, George J., Robert F. Adler, Philip Arkin, Alfred Chang, Ralph Ferraro, Arnold Gruber, John Janowiak, Alan McNab, Bruno Rudolf, Udo Schneider, 1997: The Global Precipitation Climatology Project (GPCP) Combined Precipitation Dataset. Bulletin of the American Meteorological Society: Vol. 78, No. 1, pp. 5-20.

Acknowledgements:The data set source should be acknowledged when the data are used. [One possible wording is: "The GPCP combined precipitation data were provided by the NASA/Goddard Space Flight Center's Laboratory for Atmospheres, which develops and computes the dataset as a contribution to the GEWEX Global Precipitation Climatology Project."]

The dataset creators further recommend "New users should obtain their own current, clean copy, rather than taking a version from a third party that might be damaged or out of date. Current users should check for updates and new versions to avoid reliance on out-of-date data." To do so, see the home page, under SOURCE, above.