module m_ECOSM_O2sat

      contains
c-------------------------------------------------------------------
      subroutine ECOSM_O2sat(T,S)
      implicit none

      real O2diff, O2flux, T, S
      common /O2surf/ O2flux
      real tr
*_______ Oxygen saturation micromol/liter__(Benson and Krause, 1984)
      tr=    1./(T + 273.15)
      O2flux= exp(            !     Cs [micromol/liter] = mmol/m**3 model units!
     & - 135.90205
     & + (1.575701*10.**5 ) * tr
     & - (6.642308*10.**7 ) * tr**2
     & + (1.243800*10.**10) * tr**3
     & - (8.621949*10.**11) * tr**4
     & - S*(0.017674-10.754*tr+2140.7*tr**2)  )

c      Cs= 0.0319988*Cs !    Cs [mg /liter] = 0.0319988 Cs [mmol/m**3]
c      Cs= 0.0223916*Cs !    Cs [ml /liter] = 0.0223916 Cs [mmol/m**3] ! the output units
c    write(*,*)O2_sat,T,S
c    stop
      return
      end subroutine ECOSM_O2sat
      end module m_ECOSM_O2sat