module ocean_rough_mod !----------------------------------------------------------------------- #ifdef INTERNAL_FILE_NML use mpp_mod, only: input_nml_file #else use fms_mod, only: open_namelist_file #endif use fms_mod, only: error_mesg, FATAL, file_exist, & check_nml_error, mpp_pe, mpp_root_pe, close_file, & write_version_number, stdlog use constants_mod, only: grav implicit none private public :: compute_ocean_roughness, fixed_ocean_roughness !----------------------------------------------------------------------- character(len=256) :: version = '$Id: ocean_rough.F90,v 19.0 2012/01/06 20:37:13 fms Exp $' character(len=256) :: tagname = '$Name: tikal $' !----------------------------------------------------------------------- !----- namelist ----- real :: roughness_init = 0.00044 ! not used in this version real :: roughness_min = 1.e-6 real :: charnock = 0.032 real :: roughness_mom = 5.8e-5 real :: roughness_heat = 5.8e-5 ! was 4.00e-4 real :: roughness_moist = 5.8e-5 ! real, parameter :: zcoh1 = 0.0 ! Beljaars 1994 values ! real, parameter :: zcoq1 = 0.0 ! real, parameter :: zcoh1 = 1.4e-5 ! real, parameter :: zcoq1 = 1.3e-4 real :: zcoh1 = 0.0 !miz real :: zcoq1 = 0.0 !miz logical :: do_highwind = .false. logical :: do_cap40 = .false. character(len=32) :: rough_scheme = 'fixed' ! possible values: ! 'fixed' ! 'charnock' ! 'beljaars' namelist /ocean_rough_nml/ roughness_init, roughness_heat, & roughness_mom, roughness_moist, & roughness_min, & charnock, & rough_scheme, do_highwind, &!miz do_cap40, zcoh1, zcoq1 !sjl !----------------------------------------------------------------------- logical :: do_init = .true. !----------------------------------------------------------------------- ! ---- constants ---- ! ..... high wind speed - rough sea real, parameter :: zcom1 = 1.8e-2 ! Charnock's constant ! ..... low wind speed - smooth sea real, parameter :: gnu = 1.5e-5 real, parameter :: zcom2 = 0.11 real, parameter :: zcoh2 = 0.40 real, parameter :: zcoq2 = 0.62 contains !####################################################################### subroutine compute_ocean_roughness ( ocean, u_star, & rough_mom, rough_heat, rough_moist ) logical, intent(in) :: ocean(:,:) real, intent(in) :: u_star(:,:) real, intent(out) :: rough_mom(:,:), rough_heat(:,:), rough_moist(:,:) !----------------------------------------------------------------------- ! computes ocean roughness for momentum using wind stress ! and sets roughness for heat/moisture using namelist value !----------------------------------------------------------------------- real, dimension(size(ocean,1),size(ocean,2)) :: ustar2, xx1, xx2, w10 !miz real :: a=0.001, b=0.028 !miz if (do_init) call ocean_rough_init if (trim(rough_scheme) == 'fixed') then ! --- set roughness for momentum and heat/moisture --- call fixed_ocean_roughness ( ocean, rough_mom, rough_heat, & rough_moist ) ! --- compute roughness for momentum, heat, moisture --- else if (trim(rough_scheme) == 'beljaars' .or. & trim(rough_scheme) == 'charnock') then where (ocean) ustar2(:,:) = max(gnu*gnu,u_star(:,:)*u_star(:,:)) xx1(:,:) = gnu / sqrt(ustar2(:,:)) xx2(:,:) = ustar2(:,:) / grav elsewhere rough_mom = 0.0 rough_heat = 0.0 rough_moist = 0.0 endwhere if (trim(rough_scheme) == 'charnock') then where (ocean) rough_mom (:,:) = charnock * xx2(:,:) rough_mom (:,:) = max( rough_mom(:,:), roughness_min ) rough_heat (:,:) = rough_mom (:,:) rough_moist(:,:) = rough_mom (:,:) endwhere else if (trim(rough_scheme) == 'beljaars') then ! --- Beljaars scheme --- ! SJL*** High Wind correction following Moon et al 2007 *** if (do_highwind) then if ( do_cap40 ) then where (ocean) w10(:,:) = 2.458 + u_star(:,:)*(20.255-0.56*u_star(:,:)) ! Eq(7) Moon et al. where ( w10(:,:) > 12.5 ) ! SJL mods: cap the growth of z0 with w10 up to 40 m/s ! rough_mom(:,:) = 0.001*(0.085*min(w10(:,:), 40.) - 0.58) ! capped Eq(8b) Moon et al. ! z0 (w10=40) = 2.82E-3 rough_mom(:,:) = 0.001*(0.085*w10(:,:) - 0.58) ! Eq(8b) Moon et al. rough_mom(:,:) = min( rough_mom(:,:), 2.82E-3) elsewhere rough_mom(:,:) = 0.0185/grav*u_star(:,:)**2 ! (8a) Moon et al. endwhere rough_heat (:,:) = zcoh1 * xx2(:,:) + zcoh2 * xx1(:,:) rough_moist(:,:) = zcoq1 * xx2(:,:) + zcoq2 * xx1(:,:) ! --- lower limit on roughness? --- rough_mom (:,:) = max( rough_mom (:,:), roughness_min ) rough_heat (:,:) = max( rough_heat (:,:), roughness_min ) rough_moist(:,:) = max( rough_moist(:,:), roughness_min ) endwhere else where (ocean) w10(:,:) = 2.458 + u_star(:,:)*(20.255-0.56*u_star(:,:)) ! Eq(7) Moon et al. where ( w10(:,:) > 12.5 ) rough_mom(:,:) = 0.001*(0.085*w10(:,:) - 0.58) ! Eq(8b) Moon et al. elsewhere rough_mom(:,:) = 0.0185/grav*u_star(:,:)**2 ! (8a) Moon et al. endwhere rough_heat (:,:) = zcoh1 * xx2(:,:) + zcoh2 * xx1(:,:) rough_moist(:,:) = zcoq1 * xx2(:,:) + zcoq2 * xx1(:,:) ! --- lower limit on roughness? --- rough_mom (:,:) = max( rough_mom (:,:), roughness_min ) rough_heat (:,:) = max( rough_heat (:,:), roughness_min ) rough_moist(:,:) = max( rough_moist(:,:), roughness_min ) endwhere endif ! SJL ---------------------------------------------------------------------------------------- else where (ocean) rough_mom (:,:) = zcom1 * xx2(:,:) + zcom2 * xx1(:,:) rough_heat (:,:) = zcoh1 * xx2(:,:) + zcoh2 * xx1(:,:) rough_moist(:,:) = zcoq1 * xx2(:,:) + zcoq2 * xx1(:,:) ! --- lower limit on roughness? --- rough_mom (:,:) = max( rough_mom (:,:), roughness_min ) rough_heat (:,:) = max( rough_heat (:,:), roughness_min ) rough_moist(:,:) = max( rough_moist(:,:), roughness_min ) endwhere endif endif endif !----------------------------------------------------------------------- end subroutine compute_ocean_roughness !####################################################################### subroutine fixed_ocean_roughness ( ocean, rough_mom, rough_heat, rough_moist ) logical, intent(in) :: ocean(:,:) real, intent(out) :: rough_mom(:,:), rough_heat(:,:), rough_moist(:,:) if (do_init) call ocean_rough_init where (ocean) rough_mom = roughness_mom rough_heat = roughness_heat rough_moist = roughness_moist endwhere end subroutine fixed_ocean_roughness !####################################################################### subroutine ocean_rough_init integer :: unit, ierr, io ! ----- read and write namelist ----- #ifdef INTERNAL_FILE_NML read (input_nml_file, nml=ocean_rough_nml, iostat=io) ierr = check_nml_error(io, 'ocean_rough_nml') #else if ( file_exist('input.nml')) then unit = open_namelist_file ('input.nml') ierr=1; do while (ierr /= 0) read (unit, nml=ocean_rough_nml, iostat=io, end=10) ierr = check_nml_error(io,'ocean_rough_nml') enddo 10 call close_file (unit) endif #endif !------- write version number and namelist --------- if ( mpp_pe() == mpp_root_pe() ) then call write_version_number(version, tagname) unit = stdlog() write (unit,nml=ocean_rough_nml) write (unit,11) endif !------ constants ----- roughness_moist = max (roughness_moist, roughness_min) roughness_heat = max (roughness_heat , roughness_min) roughness_mom = max (roughness_mom , roughness_min) do_init = .false. 11 format (/,'namelist option USE_FIXED_ROUGH is no longer supported', & /,'use variable ROUGH_SCHEME instead') end subroutine ocean_rough_init !####################################################################### end module ocean_rough_mod