anchor.diff:     IMPLICIT NONE
   
   !  Input & output variables:
  -   REAL(kind=r8), INTENT(in) :: temp
  +   REAL(kind=r8), INTENT(in) :: Tc
      REAL(kind=r8) :: sco2
   
  -   sco2 = 1920.4 - 135.6*temp  + 5.2122*temp**2 - 0.10939*temp**3  + 0.00093777*temp**4
  +   sco2 = 1920.4 - 135.6*Tc  + 5.2122*Tc**2 - 0.10939*Tc**3  + 0.00093777*Tc**4
   
      RETURN
   END FUNCTION sco2
  
positive.code:   RETURN
  END SUBROUTINE vapress
  
  END MODULE gasx
  
negative.code:   RETURN
  END SUBROUTINE pCO2atm2xCO2
  
  !>    Compute piston velolicty kw660 (at 25 C) from wind speed
  SUBROUTINE pistonvel(windspeed, Fice, N, kw660)
    !    Purpose:
    !    Compute piston velocity from wind speed, BUT without Schmidt number temperature correction (Sc differs each gas)
  
    USE msingledouble
  
    IMPLICIT NONE
  
    !> number of records
    INTEGER, intent(in) :: N
  
  ! INPUT variables
    !> wind speed at 10-m height
    REAL(kind=r8), INTENT(out), DIMENSION(N) :: windspeed
    !> modeled sea-ice cover: fraction of grid cell, varying between 0.0 (no ice) and 1.0 (full cover)
    REAL(kind=r8), INTENT(out), DIMENSION(N) :: windspeed
  !f2py optional , depend(windspeed) :: n=len(windspeed)
  
  ! OUTPUT variables:
    !> piston velocity at 25°C [m/s], uncorrected by the Schmidt number for different temperatures
    REAL(kind=r4), INTENT(out), DIMENSION(N) :: kw660
  
  ! LOCAL variables:
    REAL(kind=r8) :: a, xfac
  
    INTEGER :: i
  
  ! Coefficient from Wanninkhof (2014, Limnol. Oceanograph. Methods, 12, 351-362)
    a = 0.251d0
  
  ! Conversion factor to convert from cm/h to m/s
    xfac = 0.01d0 / 3600d0
    
    DO i = 1,N
       kw660(i) = a * windspeed(i)**2) * (1.0d0 - Fice) * xfac
    END DO
  
    RETURN
  END SUBROUTINE pistonvel
  
  !>    Compute Schmidt number for CFC11 in seawater from temperature
  FUNCTION sccfc11(temp)
  
  