! $Header: /u/gcmpack/MITgcm/pkg/atm_phys/surface_flux_mod.F90,v 1.1 2013/05/08 22:14:15 jmc Exp $ ! $Name: $ ! ============================================================================ module surface_flux_mod ! ============================================================================ ! use fms_mod, only: FATAL, close_file, mpp_pe, mpp_root_pe, & ! write_version_number ! use fms_mod, only: file_exist, check_nml_error, open_namelist_file, stdlog use monin_obukhov_mod, only: mo_drag, mo_profile use simple_sat_vapor_pres_mod, only: escomp, descomp use gcm_params_mod, only: gcm_LEN_MBUF, gcm_SQZ_R, gcm_stdMsgUnit use constants_mod, only: cp_air, hlv, stefan, rdgas, rvgas, grav implicit none private ! ==== public interface ====================================================== public surface_flux ! ==== end of public interface =============================================== interface surface_flux ! module procedure surface_flux_0d ! module procedure surface_flux_1d module procedure surface_flux_2d end interface !----------------------------------------------------------------------- character(len=*), parameter :: version = '$Id: surface_flux_mod.F90,v 1.1 2013/05/08 22:14:15 jmc Exp $' character(len=*), parameter :: tagname = '$Name: $' logical :: do_init = .true. real, parameter :: d622 = rdgas/rvgas real, parameter :: d378 = 1.-d622 real, parameter :: hlars = hlv/rvgas real, parameter :: gcp = grav/cp_air real, parameter :: kappa = rdgas/cp_air real :: d608 = d378/d622 ! d608 set to zero at initialization if the use of ! virtual temperatures is turned off in namelist ! ---- namelist with default values ------------------------------------------ logical :: no_neg_q = .false. ! for backwards compatibility logical :: use_virtual_temp = .true. logical :: alt_gustiness = .false. logical :: use_mixing_ratio = .false. real :: gust_const = 1.0 namelist /surface_flux_nml/ no_neg_q, & use_virtual_temp, & alt_gustiness, & gust_const, & use_mixing_ratio contains ! ============================================================================ subroutine surface_flux_1d ( & t_atm, q_atm_in, u_atm, v_atm, p_atm, z_atm, & p_surf, t_surf, t_ca, q_surf, & u_surf, v_surf, & rough_mom, rough_heat, rough_moist, gust, & flux_t, flux_q, flux_r, flux_u, flux_v, & cd_m, cd_t, cd_q, & w_atm, u_star, b_star, q_star, & dhdt_surf, dedt_surf, dedq_surf, drdt_surf, & dhdt_atm, dedq_atm, dtaudv_atm, & ! + slm Mar 28 2002 -- it is not necessary here since it is just cd_q*wind ! drag_q, & ! - slm Mar 28 2002 dt, land, avail, myThid ) ! ============================================================================ ! ---- arguments ----------------------------------------------------------- logical, intent(in), dimension(:) :: land, avail real, intent(in), dimension(:) :: & t_atm, q_atm_in, u_atm, v_atm, & p_atm, z_atm, t_ca, & p_surf, t_surf, u_surf, v_surf, & rough_mom, rough_heat, rough_moist, gust real, intent(out), dimension(:) :: & flux_t, flux_q, flux_r, flux_u, flux_v, & dhdt_surf, dedt_surf, dedq_surf, drdt_surf, & dhdt_atm, dedq_atm, dtaudv_atm, & w_atm, u_star, b_star, q_star, & cd_m, cd_t, cd_q real, intent(inout), dimension(:) :: q_surf real, intent(in) :: dt integer, intent(in) :: myThid ! ---- local constants ----------------------------------------------------- ! temperature increment and its reciprocal value for comp. of derivatives real, parameter:: del_temp=0.1, del_temp_inv=1.0/del_temp ! ---- local vars ---------------------------------------------------------- real, dimension(size(t_atm)) :: & thv_atm, th_atm, tv_atm, thv_surf, & e_sat, e_sat1, q_sat, q_sat1, p_ratio, & t_surf0, t_surf1, u_dif, v_dif, & rho_drag, drag_t, drag_m, drag_q, rho, & q_atm, q_surf0 integer :: i, nbad if (do_init) call surface_flux_init(myThid) !---- use local value of surf temp ---- t_surf0 = 200. ! avoids out-of-bounds in es lookup where (avail) where (land) t_surf0 = t_ca elsewhere t_surf0 = t_surf endwhere endwhere t_surf1 = t_surf0 + del_temp call escomp ( t_surf0, e_sat ) ! saturation vapor pressure call escomp ( t_surf1, e_sat1 ) ! perturbed vapor pressure if(use_mixing_ratio) then ! surface mixing ratio at saturation q_sat = d622*e_sat /(p_surf-e_sat ) q_sat1 = d622*e_sat1/(p_surf-e_sat1) else ! surface specific humidity at saturation q_sat = d622*e_sat /(p_surf-d378*e_sat ) q_sat1 = d622*e_sat1/(p_surf-d378*e_sat1) endif ! initilaize surface air humidity according to surface type where (land) q_surf0 = q_surf ! land calculates it elsewhere q_surf0 = q_sat ! everything else assumes saturated sfc humidity endwhere ! check for negative atmospheric humidities where(avail) q_atm = q_atm_in if(no_neg_q) then where(avail .and. q_atm_in < 0.0) q_atm = 0.0 endif ! generate information needed by monin_obukhov where (avail) p_ratio = (p_surf/p_atm)**kappa tv_atm = t_atm * (1.0 + d608*q_atm) ! virtual temperature th_atm = t_atm * p_ratio ! potential T, using p_surf as refernce thv_atm = tv_atm * p_ratio ! virt. potential T, using p_surf as reference thv_surf= t_surf0 * (1.0 + d608*q_surf0 ) ! surface virtual (potential) T ! thv_surf= t_surf0 ! surface virtual (potential) T -- just for testing tun off the q_surf u_dif = u_surf - u_atm ! velocity components relative to surface v_dif = v_surf - v_atm endwhere if(alt_gustiness) then where(avail) & w_atm = max(sqrt(u_dif*u_dif + v_dif*v_dif), gust_const) else where(avail) & w_atm = sqrt(u_dif*u_dif + v_dif*v_dif + gust*gust) endif ! monin-obukhov similarity theory call mo_drag (thv_atm, thv_surf, z_atm, & rough_mom, rough_heat, rough_moist, w_atm, & cd_m, cd_t, cd_q, u_star, b_star, myThid, avail ) where (avail) ! surface layer drag coefficients drag_t = cd_t * w_atm drag_q = cd_q * w_atm drag_m = cd_m * w_atm ! density rho = p_atm / (rdgas * tv_atm) ! sensible heat flux rho_drag = cp_air * drag_t * rho flux_t = rho_drag * (t_surf0 - th_atm) ! flux of sensible heat (W/m**2) dhdt_surf = rho_drag ! d(sensible heat flux)/d(surface temperature) dhdt_atm = -rho_drag*p_ratio ! d(sensible heat flux)/d(atmos temperature) ! evaporation rho_drag = drag_q * rho flux_q = rho_drag * (q_surf0 - q_atm) ! flux of water vapor (Kg/(m**2 s)) where (land) dedq_surf = rho_drag dedt_surf = 0 elsewhere dedq_surf = 0 dedt_surf = rho_drag * (q_sat1 - q_sat) *del_temp_inv endwhere dedq_atm = -rho_drag ! d(latent heat flux)/d(atmospheric mixing ratio) q_star = flux_q / (u_star * rho) ! moisture scale ! ask Chris and Steve K if we still want to keep this for diagnostics q_surf = q_atm + flux_q / (rho*cd_q*w_atm) ! surface specific humidity ! upward long wave radiation flux_r = stefan*t_surf**4 ! (W/m**2) drdt_surf = 4*stefan*t_surf**3 ! d(upward longwave)/d(surface temperature) ! stresses rho_drag = drag_m * rho flux_u = rho_drag * u_dif ! zonal component of stress (Nt/m**2) flux_v = rho_drag * v_dif ! meridional component of stress dtaudv_atm = -rho_drag ! d(stress component)/d(atmos wind) elsewhere ! zero-out un-available data in output only fields flux_t = 0.0 flux_q = 0.0 flux_r = 0.0 flux_u = 0.0 flux_v = 0.0 dhdt_surf = 0.0 dedt_surf = 0.0 dedq_surf = 0.0 drdt_surf = 0.0 dhdt_atm = 0.0 dedq_atm = 0.0 dtaudv_atm = 0.0 u_star = 0.0 b_star = 0.0 q_star = 0.0 q_surf = 0.0 w_atm = 0.0 endwhere end subroutine surface_flux_1d !####################################################################### subroutine surface_flux_0d ( & t_atm_0, q_atm_0, u_atm_0, v_atm_0, p_atm_0, z_atm_0, & p_surf_0, t_surf_0, t_ca_0, q_surf_0, & u_surf_0, v_surf_0, & rough_mom_0, rough_heat_0, rough_moist_0, gust_0, & flux_t_0, flux_q_0, flux_r_0, flux_u_0, flux_v_0, & cd_m_0, cd_t_0, cd_q_0, & w_atm_0, u_star_0, b_star_0, q_star_0, & dhdt_surf_0, dedt_surf_0, dedq_surf_0, drdt_surf_0, & dhdt_atm_0, dedq_atm_0, dtaudv_atm_0, & dt, land_0, avail_0, myThid ) ! ---- arguments ----------------------------------------------------------- logical, intent(in) :: land_0, avail_0 real, intent(in) :: & t_atm_0, q_atm_0, u_atm_0, v_atm_0, & p_atm_0, z_atm_0, t_ca_0, & p_surf_0, t_surf_0, u_surf_0, v_surf_0, & rough_mom_0, rough_heat_0, rough_moist_0, gust_0 real, intent(out) :: & flux_t_0, flux_q_0, flux_r_0, flux_u_0, flux_v_0, & dhdt_surf_0, dedt_surf_0, dedq_surf_0, drdt_surf_0, & dhdt_atm_0, dedq_atm_0, dtaudv_atm_0, & w_atm_0, u_star_0, b_star_0, q_star_0, & cd_m_0, cd_t_0, cd_q_0 real, intent(inout) :: q_surf_0 real, intent(in) :: dt integer, intent(in) :: myThid ! ---- local vars ---------------------------------------------------------- logical, dimension(1) :: land, avail real, dimension(1) :: & t_atm, q_atm, u_atm, v_atm, & p_atm, z_atm, t_ca, & p_surf, t_surf, u_surf, v_surf, & rough_mom, rough_heat, rough_moist, gust real, dimension(1) :: & flux_t, flux_q, flux_r, flux_u, flux_v, & dhdt_surf, dedt_surf, dedq_surf, drdt_surf, & dhdt_atm, dedq_atm, dtaudv_atm, & w_atm, u_star, b_star, q_star, & cd_m, cd_t, cd_q real, dimension(1) :: q_surf avail = .true. t_atm(1) = t_atm_0 q_atm(1) = q_atm_0 u_atm(1) = u_atm_0 v_atm(1) = v_atm_0 p_atm(1) = p_atm_0 z_atm(1) = z_atm_0 p_surf(1) = p_surf_0 t_surf(1) = t_surf_0 u_surf(1) = u_surf_0 v_surf(1) = v_surf_0 rough_mom(1) = rough_mom_0 rough_heat(1) = rough_heat_0 rough_moist(1) = rough_moist_0 gust(1) = gust_0 call surface_flux_1d ( & t_atm, q_atm, u_atm, v_atm, p_atm, z_atm, & p_surf, t_surf, t_ca, q_surf, & u_surf, v_surf, & rough_mom, rough_heat, rough_moist, gust, & flux_t, flux_q, flux_r, flux_u, flux_v, & cd_m, cd_t, cd_q, & w_atm, u_star, b_star, q_star, & dhdt_surf, dedt_surf, dedq_surf, drdt_surf, & dhdt_atm, dedq_atm, dtaudv_atm, & dt, land, avail, myThid ) flux_t_0 = flux_t(1) flux_q_0 = flux_q(1) flux_r_0 = flux_r(1) flux_u_0 = flux_u(1) flux_v_0 = flux_v(1) dhdt_surf_0 = dhdt_surf(1) dedt_surf_0 = dedt_surf(1) drdt_surf_0 = drdt_surf(1) dedq_surf_0 = dedq_surf(1) dhdt_atm_0 = dhdt_atm(1) dedq_atm_0 = dedq_atm(1) dtaudv_atm_0 = dtaudv_atm(1) w_atm_0 = w_atm(1) u_star_0 = u_star(1) b_star_0 = b_star(1) q_star_0 = q_star(1) q_surf_0 = q_surf(1) cd_m_0 = cd_m(1) cd_t_0 = cd_t(1) cd_q_0 = cd_q(1) end subroutine surface_flux_0d subroutine surface_flux_2d ( & t_atm, q_atm_in, u_atm, v_atm, p_atm, z_atm, & p_surf, t_surf, t_ca, q_surf, & u_surf, v_surf, & rough_mom, rough_heat, rough_moist, gust, & flux_t, flux_q, flux_r, flux_u, flux_v, & cd_m, cd_t, cd_q, & w_atm, u_star, b_star, q_star, & dhdt_surf, dedt_surf, dedq_surf, drdt_surf, & dhdt_atm, dedq_atm, dtaudv_atm, & dt, land, avail, myThid ) ! ---- arguments ----------------------------------------------------------- logical, intent(in), dimension(:,:) :: land, avail real, intent(in), dimension(:,:) :: & t_atm, q_atm_in, u_atm, v_atm, & p_atm, z_atm, t_ca, & p_surf, t_surf, u_surf, v_surf, & rough_mom, rough_heat, rough_moist, gust real, intent(out), dimension(:,:) :: & flux_t, flux_q, flux_r, flux_u, flux_v, & dhdt_surf, dedt_surf, dedq_surf, drdt_surf, & dhdt_atm, dedq_atm, dtaudv_atm, & w_atm, u_star, b_star, q_star, & cd_m, cd_t, cd_q real, intent(inout), dimension(:,:) :: q_surf real, intent(in) :: dt integer, intent (in) :: myThid ! ---- local vars ----------------------------------------------------------- integer :: j do j = 1, size(t_atm,2) call surface_flux_1d ( & t_atm(:,j), q_atm_in(:,j), u_atm(:,j), v_atm(:,j), p_atm(:,j), z_atm(:,j), & p_surf(:,j), t_surf(:,j), t_ca(:,j), q_surf(:,j), & u_surf(:,j), v_surf(:,j), & rough_mom(:,j), rough_heat(:,j), rough_moist(:,j), gust(:,j), & flux_t(:,j), flux_q(:,j), flux_r(:,j), flux_u(:,j), flux_v(:,j), & cd_m(:,j), cd_t(:,j), cd_q(:,j), & w_atm(:,j), u_star(:,j), b_star(:,j), q_star(:,j), & dhdt_surf(:,j), dedt_surf(:,j), dedq_surf(:,j), drdt_surf(:,j), & dhdt_atm(:,j), dedq_atm(:,j), dtaudv_atm(:,j), & dt, land(:,j), avail(:,j), myThid ) end do end subroutine surface_flux_2d ! ============================================================================ subroutine surface_flux_init (myThid) ! ============================================================================ ! initializes surface flux module ! ---- local vars ---------------------------------------------------------- integer, intent(in) :: myThid integer :: unit, ierr, io !-- added: integer :: iUnit CHARACTER*(gcm_LEN_MBUF) :: msgBuf ! read namelist ! _BARRIER ! _BEGIN_MASTER(myThid) CALL BARRIER(myThid) IF ( myThid.EQ.1 ) THEN WRITE(msgBuf,'(A)') 'SURFACE_FLUX_INIT: opening data.atm_gray' CALL PRINT_MESSAGE( msgBuf, gcm_stdMsgUnit, gcm_SQZ_R, myThid ) CALL OPEN_COPY_DATA_FILE( & 'data.atm_gray', 'SURFACE_FLUX_INIT', & iUnit, & myThid ) ! Read parameters from open data file READ(UNIT=iUnit,NML=surface_flux_nml) WRITE(msgBuf,'(A)') & 'SURFACE_FLUX_INIT: finished reading data.atm_gray' CALL PRINT_MESSAGE( msgBuf, gcm_stdMsgUnit, gcm_SQZ_R, myThid ) ! Close the open data file CLOSE(iUnit) ! if ( file_exist('input.nml')) then ! unit = open_namelist_file () ! ierr=1; ! do while (ierr /= 0) ! read (unit, nml=surface_flux_nml, iostat=io, end=10) ! ierr = check_nml_error(io,'surface_flux_nml') ! enddo !10 call close_file (unit) ! endif ! ! write version number ! call write_version_number(version, tagname) ! if ( mpp_pe() == mpp_root_pe() ) write (stdlog(), nml=surface_flux_nml) ! if(.not. use_virtual_temp) d608 = 0.0 do_init = .false. ENDIF CALL BARRIER (myThid) end subroutine surface_flux_init end module surface_flux_mod