C==================================================================
C PROGRAM TO READ ONE DEGREE GRIDDED POPULATION DATA AND THE 
C  NASA-GISS COUNTRY/REGION-PROVINCE IDENTIFICATION CODES
C==================================================================

      INTEGER POP(180,360)
      INTEGER IJCODE(180,360)
C
      OPEN(10,FILE='POPMOD.DAT',STATUS='OLD')
      OPEN(20,FILE='CNTYMOD.DAT',STATUS='OLD')
      OPEN(30,FILE='MOD.OUT',STATUS='UNKNOWN')
C
      SUM=0.D0
      WRITE(30,*)'POPULATION & NASA-GISS-ID'
C FROM NORTH > SOUTH
      DO 10 I=1,180
C FROM WEST > EAST:
         DO 10 J=1,360
            READ(10,'(I10)')POP(I,J)
            READ(20,'(I6)')IJCODE(I,J)
            SUM=SUM+POP(I,J)
C ECHO PRINT:
            WRITE(30,*)POP(I,J),IJCODE(I,J)
10      CONTINUE
      PRINT *,SUM
      CLOSE (UNIT=10)
      CLOSE (UNIT=20)
      CLOSE (UNIT=30)
      STOP
      END
C==================================================================