CRU05 1901-1996 0.5o Latitude/Longitude Monthly Climate Data
23 August 1998

Variables                    Directory     Units   
Precipitation                pre           mm
Wet day frequency            rd0           days
Mean temperature             tmp           degC*10
Diurnal temperature range    dtr           degC*10
Vapour pressure              vap           hPa*10
Cloud cover                  cld           oktas*10

Format (ascii)
One file per year per variable.
The first and second lines of the file contain information on the grid size,
 for example, for a global field:
grd_sz    xmin    ymin    xmax    ymax  n_cols  n_rows n_months 
 0.5    -179.75  -89.75  189.75  89.75    720     360     12

This is followed by 12 monthly grids that are n_cols by n_rows in
size.
Each record contains n_cols longitude values, format n_colsi5, 
starting at xmin and ending at xmax
The first record starts at January, ymin and the last record is the
row for December, ymax.
Missing values (Antarctica, oceans and major inland water bodies) are 
assigned values of -9999.

To read in one year of data the following program should work:

      program rd_ascii
c f90 program to read in an integer ascii grid with
c  variable dimensions into a global grid (720x360x12)
c
      parameter (n_cols=720,n_rows=360)  
      integer*2 grid(n_cols,n_rows,12)
      character infl*72,fmt*20
      call getarg(1,infl)
      if(infl.eq.' ')then
       write(*,*) 'Enter ascii grid file name'
       read(*,'(a72)')infl
      endif
      open(1,file=infl,status='old')
      read(1,*)
      read(1,*)gs,xmin,ymin,xmax,ymax,ncols,nrows,nmonths
      grid=-9999
      fmt='(   i5)'
      write(fmt(2:4),'(i3)')n_cols
      do im=1,nmonths
       do lat=1,n_rows
        read(1,fmt)(grid(lon,lat,im),lon=1,n_cols)
       enddo
      enddo
      end