CPC Merged Analysis of Precipitation (CMAP)

monthly precipitation by merging gauge, 5 kinds of satellite estimates (GPI,OPI,SSM/I scattering, SSM/I emission and MSU) and (optionally) numerical model predictions.


Xie, P., and P. A. Arkin, 1996: Analyses of Global Monthly Precipitation Using Gauge Observations, Satellite Estimates, and Numerical Model Predictions. J. Climate, 9, 840 -858.

Xie, P., and P. A. Arkin, 1997: Global Precipitation: A 17-Year Monthly Analysis Based on Gauge Observations, Satellite Estimates and NUmerical Model Outputs. BAMS, 78, 2539-2558.

Please contact us for any problems or questions regarding to this product which is experimental in nature.

   Dr. Pingping Xie 
   National Centers for Environmental Prediction, #800A 
   National Oceanic and Atmospheric Administration  
   Washington, DC 20233 
   Tel:  (301)763-8167 
   Fax:  (301)763-8125 
   E-mail:  xping@sgi17.wwb.noaa.gov

The following information is from the "cmap_mon_v1101.announcement" file associated with this dataset:

Dear Colleagues, 

This is to announce the release of our updated data  
set of global monthly precipitation which we call
monthly CMAP (CPC Merged Analysis of Precipitation). 

The current version of the data set covers a 31-years
and 10 months period from January 1979 to October 2010. 

For the period from Jan.1979 to September 2009, the 
analysis is the same as in the previous version (v1001).   

!!!!!!!!!!!!!!!!!!   NOTICE   !!!!!!!!!!!!!!!!!!!!!!!!!!!!
Due to changes in the input data sets, discontinuities may observe 
in the analysis between periods before and after 2009.  While we 
are working on the issues, users should be cautious in 
applications where high quantitative accuracy is required. 

You may get the compressed ASCII data files along with
a document file through ftp:  

        ftp ftpprd.ncep.noaa.gov  
        name:  anonymous 
        passwd:  (your e-mail address) 
        cd /pub/precip/cmap/monthly  
        get cmap_mon_v1101_yy.txt.gz    (data file for 19yy, or 20yy) 
        get cmap_mon_v1101.doc.gz       (document)

Please check the above mentioned ftp site for updates
and extensions of the data set.

Please contact us if you have any problems or questions
concerning the merged analysis data. 

Please be advised that the CMAP data set may contain an artificial 
downward trend for period after 1996. Cares must be taken when using
the data set for accurate quantitative applications.   

Thanks for your interest!

Pingping Xie