CMORPH 0.25 degree 3-hourly Precipitation Data 

This data set contains  0.25 degree resolution 3-hourly global CMORPH 
precipitation data during DYNAMO (August 2011 through March 2012).  
CMORPH is the CPC Morphing technique which derives precipitation estimates
from low orbiter satellite microwave observations.  The data are in binary format and
were provided by NOAA/CPC.
		 

The data are compressed using the standard Unix compress function (files have a
suffix of ".Z"). Each file is composed of 16 direct access binary
("big_endian") records that are defined as follows:

Record 1: contains the merged microwave precipitation only for 00 UTC
Record 2: contains the "CMORPH" precipitation estimates for 00 UTC

Record 3: contains the merged microwave precipitation only for 03 UTC
Record 4: contains the "CMORPH" precipitation estimates for 03 UTC

Record 5: contains the merged microwave precipitation only for 06 UTC;
Record 6: contains the "CMORPH" precipitation estimates for 06 UTC;

Record 7: contains the merged microwave precipitation only for 09 UTC;
Record 8: contains the "CMORPH" precipitation estimates for 09 UTC;

Record 9: contains the merged microwave precipitation only for 12 UTC;
Record 10: contains the "CMORPH" precipitation estimates for 12 UTC;

Record 11: contains the merged microwave precipitation only for 15 UTC;
Record 12: contains the "CMORPH" precipitation estimates for 15 UTC;

Record 13: contains the merged microwave precipitation only for 18 UTC;
Record 14: contains the "CMORPH" precipitation estimates for 18 UTC;
 
Record 15: contains the merged microwave precipitation only for 21 UTC
Record 16: contains the "CMORPH" precipitation estimates for 21 UTC

All units are "mm/hr".  Missing data are denoted by values of "-9999."
Each record contains a 1440 x 480 REAL*4 array of data which is oriented
from 0.125E EASTward and from 59.875N SOUTHward, with a grid increment
of 0.25 degrees of latitude and longitude.  Thus, the grid locations
are the centers od a 0.25 degree lat/lon grid box.  Note that these 
estimates represent spatial averages, so the data are grid-centered, 
rather than lattice-centered.

For example (1,1) is 0.125E, 59.875N 
            (2,2) is 0.375E, 59.625N, etc.

There is an associated GrADS ctl file included with your order:
CMORPH+MWCOMB_025deg-3hr.ctl 

For further information about these data see the reference:

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. 
 
The data were provided by Robert Joyce (robert.joyce@noaa.gov) from NOAA/CPC.


Below is FORTRAN code (run on an SGI) that will read the data sets:

      program cread
c    program cpc_advt+comb_read.f

      parameter (IRMAX=1440, JRMAX=480, PMAX=2)

      real*4 ssmipropREG(IRMAX,JRMAX,PMAX)
      character*115 in1ssmipropREG

      iyrmndy = 20031110
      irec = 0

c    Open input regional blended sensor rainfall file for 3
c      hour CPC micro rainfall file

      in1ssmipropREG = '/export-2/sgi109/irstat/blended_tech/cpc/data/02
     &5deg/YYYY0M0D_3hr-025deg_cpc+comb'

      write (in1ssmipropREG(54:61),'(i8)') iyrmndy
        write(6,'('' file '',a88)') in1ssmipropREG

      open (unit=15, file=in1ssmipropREG, access='direct',
     &              recl=1440*480*2*4, form='unformatted')

c    Loop over 8 3 hourly periods for one day
      do ihr = 0, 21, 3

       irec = irec + 1

       write(6,'(//,''proc 3 hr starting '',i8,i4)') iyrmndy, ihr

       read (15, rec = irec) ssmipropREG

       write (6,'(/,'' cpc combined MW '')')
       do jreg = 271, 280
        write(6,'(15(f5.1))') (ssmipropREG(ireg,jreg,1),ireg=1161,1175)
       enddo

       write (6,'(/,'' CMORPH '')')
       do jreg = 271, 280
        write(6,'(15(f5.1))') (ssmipropREG(ireg,jreg,2),ireg=1161,1175)
       enddo

c    End 3 hour loop

      enddo

      close (15)

      stop

      end