!-------- SENGEN �錾��
      implicit none
      integer col,lin,i,j,j2,col2
      parameter(col=141,lin=121)
      real adt(col,lin),dlat,dlon,longitude
      real(8) lat1,lat2,dist,dadt,coli,g,pi,gv,mlat

!--------- Parameters
      g=9.8; pi=3.141592
 
!--------- Read satellite data
      open(10,file="2012-05.madt.141x121.flat",access="direct",
     1 form='unformatted',status="old",recl=col*lin*4)
      read(10,rec=1) adt
      close(10)

!--------- Calculate column value based on Longitude value
      write(*,*) "Enter Longitude you want to calculate Geo. Vel."
      read(*,*) longitude
      dlon=(155.14-120.17)/141
      col2=int((longitude-120.17-0.5*dlon)/(dlon)+1)

!--------- Calculate Geostrophic Velocity along given longitude
      do i=col2,col2
      do j=1,lin-1
       dlat=(55.05-25.09)/121.
       j2=j+1
       lat1=55.05-(j-1)*dlat
       lat2=55.05-(j2-1)*dlat
       mlat=(lat1+lat2)*0.5

        call DISTLL(lat1,longitude,lat2,longitude,dist)
        dadt=-999
        if(adt(i,j).ne.-999.and.adt(i,j2).ne.-999)then
        if(dadt.ne.0)then
        dadt=adt(i,j)-adt(i,j2)

        coli=2*7.2*1.0e-5*sin(mlat*pi/180.0)
        gv=-(g/coli)*(dadt*0.01)/(dist*1000)

        else
        gv=-999
        endif
        else
        gv=-999
        endif

       write(*,100) longitude,lat1,lat2,adt(i,j),adt(i,j2),
     1 dadt,dist,gv
100    format("Longitude(E)=",f12.4," LAT1(N)=",f8.4," LAT2(N)=",f7.4,
     1 " adt1(cm)=",f9.4," adt2(cm)= ",f9.4,
     1 " dadt(cm)=",f12.4," Distance(km)= ",f10.4,
     1 "     gv(m/s)=",f12.4)

       enddo
      enddo

      stop
      end