CMAP
CPC Merged Analysis of Precipitation
CMAP includes monthly and pentad global gridded precipitation means. It has a standard version and one enhanced with NCEP Reanalysis. CMAP covers from 1979 to near the present on a global grid at 2.5 degree latitude x 2.5 degree longitude resolution. For more information you can check the original data soruce on the NOAA Physical Sceince Laboratory (PSL) website and the UCAR climate data guide for a review of the dataset. The original data is created by NOAA Climate Prediction Center (CPC) and it is in ascii format, we download a netcdf version from PSL. For this reason the PSL data is updated irregularly, following updates at CPC.
CMAP at NCI
We downloaded CMAP in
/g/data/ua8/Precipitation/CMAP
There are two sub-folders:
- enh - for enhanced monthly
- precip.mon.ltm.nc - enhanced long term monthly mean, derived from years 1981 to 2010
- precip.mon.mean.nc - enhanced monthly mean from 1979/01 to 2021/03
- precip.pentad.mean.nc - enhanced pentad mean from 1979/01 to 2016/12/27
- std - for standard monthly
- precip.mon.ltm.nc - standard long term monthly mean, derived from years 1981 to 2010
- precip.mon.mean.nc - standard monthly mean from 1979/01 to 2021/03
- precip.pentad.mean.nc - standard pentad mean from 1979/01 to 2016/12/27
The files get updated occasionally, the information on the days the files have been updated and the actual creation date for the file themselves are in:
/g/data/ua8/Precipitation/CMAP/updates.txt
The previous version of the files is kept in /g/data/ua8/Precipitation/CMAP/<std/enh>/previous_version/ for reference only.
Citation
- Xie, P., and P.A. Arkin, 1997: Global precipitation: A 17-year monthly analysis based on gauge observations, satellite estimates, and numerical model outputs. Bull. Amer. Meteor. Soc., 78, 2539 - 2558.
Please note: If you acquire CMAP Precipitation data products from PSL, we ask that you acknowledge us in your use of the data. This may be done by including text such as
CMAP Precipitation data provided by the NOAA/OAR/ESRL PSL, Boulder, Colorado, USA, from their Web site at https://psl.noaa.gov/data/gridded/data.cmap.html on the <date>
use the updated <date> from the download log updates.txt
in any documents or publications using these data. We would also appreciate receiving a copy of the relevant publications. This will help PSL to justify keeping the CMAP Precipitation data set freely available online in the future.
References
- Huffman, G. J. and co-authors, 1997: The Global Precipitation Climatology Project (GPCP) combined data set. Bull. Amer. Meteor. Soc., 78, 5-20.
- Reynolds, R. W., 1988: A real-time global sea surface temperature analysis. J. Climate, 1, 75-86.
- Spencer, R. W., 1993: Global oceanic precipitation from the MSU during 1979-91 and comparisons to other climatologies. J. Climate, 6, 1301-1326.
- Xie P., and P. A. Arkin, 1997: Global precipitation: a 17-year monthly analysis based on gauge observations, satellite estimates, and numerical model outputs. Bull. Amer. Meteor. Soc., 78, 2539-2558.