Monthly Analysis of Global Land Precipitation from 1948 to the Present 

1.   file name

     precl_mon_v1.0.lnx.yyyy.gri0.5m
     (yyyy = 1948-current)

2.   description of the data
    
     1) content:
        rain == monthly precipitation based on gauge observations from 
                GHCN version 2B and CAMS in (0.1 mm/day) 
                (e.g. 234.0 is 23.4 mm/day); 
        gauge_num == number of gauges in the grid box (0.5x0.5lat/lon);  

     2) coverage:
        -89.75S -- 89.75N;
        0.25E -> Eastward -> 0.25W;
        from January 1948 to current;

     3) spatical resolution :
        0.5 deg lat x 0.5 deg lon;
   
     4) missing values
        -999.0

     5) format
        direct access binary format in little endian template 

3.   example program

c      program    :    example
c      projective :    to read the monthly gauge analysis data
c                      for 1948 
c
       dimension    rain(720,360),gauge_num(720,360)
c
c      1.  to open the data file
c
       open  (unit=10,file='precl_mon_v1.0.sgi.1948.gri0.5m',
     #       access='direct',status='old',
     #       recl=720*360*4)
c
c      2.  to read the data
c
       do  2001 kmon = 1, 12
           kinp = (kmon-1)*2 + 1
           read (10,rec=kinp) rain
           kinp = (kmon-1)*2 + 2
           read (10,rec=kinp) gauge_num
 2001  continue
c
       stop
       end
c

4.  references:
   
    Chen, M., P. Xie, J. E. Janowiak, and P. A. Arkin, Global Land 
          Precipiation: A 50-yr Monthly Analysis Based on Gauge 
          Observations, 2002, J. Hydrometeor., 3, 249-266. 

5.  contacts:

    Please contact us for any problems or questions regarding 
    this product. 

    Dr. Mingyue Chen
    Climate Prediction Center
    5200 Auth Road, Room #605
    Camp Spings MD 20746
    Tel:  (301) 763-8000 ext. 7506
    Fax:  (301) 763-8125 
    E-mail:  mingyue.chen@noaa.gov