MODULE sbcblk_clio !!====================================================================== !! *** MODULE sbcblk_clio *** !! Ocean forcing: bulk thermohaline forcing of the ocean (or ice) !!===================================================================== !! History : OPA ! 1997-06 (Louvain-La-Neuve) Original code !! ! 2001-04 (C. Ethe) add flx_blk_declin !! NEMO 2.0 ! 2002-08 (C. Ethe, G. Madec) F90: Free form and module !! 3.0 ! 2008-03 (C. Talandier, G. Madec) surface module + LIM3 !! 3.2 ! 2009-04 (B. Lemaire) Introduce iom_put !!---------------------------------------------------------------------- !!---------------------------------------------------------------------- !! sbc_blk_clio : CLIO bulk formulation: read and update required input fields !! blk_clio_oce : ocean CLIO bulk formulea: compute momentum, heat and freswater fluxes for the ocean !! blk_ice_clio : ice CLIO bulk formulea: compute momentum, heat and freswater fluxes for the sea-ice !! blk_clio_qsr_oce : shortwave radiation for ocean computed from the cloud cover !! blk_clio_qsr_ice : shortwave radiation for ice computed from the cloud cover !! flx_blk_declin : solar declination !!---------------------------------------------------------------------- USE oce ! ocean dynamics and tracers USE dom_oce ! ocean space and time domain USE phycst ! physical constants USE fldread ! read input fields USE sbc_oce ! Surface boundary condition: ocean fields USE iom ! I/O manager library USE in_out_manager ! I/O manager USE lib_mpp ! distribued memory computing library USE wrk_nemo ! work arrays USE timing ! Timing USE lbclnk ! ocean lateral boundary conditions (or mpp link) USE lib_fortran ! Fortran utilities (allows no signed zero when 'key_nosignedzero' defined) USE albedo USE prtctl ! Print control #if defined key_lim3 USE ice USE sbc_ice ! Surface boundary condition: ice fields USE limthd_dh ! for CALL lim_thd_snwblow #elif defined key_lim2 USE ice_2 USE sbc_ice ! Surface boundary condition: ice fields USE par_ice_2 ! Surface boundary condition: ice fields #endif IMPLICIT NONE PRIVATE PUBLIC sbc_blk_clio ! routine called by sbcmod.F90 #if defined key_lim2 || defined key_lim3 PUBLIC blk_ice_clio_tau ! routine called by sbcice_lim.F90 PUBLIC blk_ice_clio_flx ! routine called by sbcice_lim.F90 #endif INTEGER , PARAMETER :: jpfld = 7 ! maximum number of files to read INTEGER , PARAMETER :: jp_utau = 1 ! index of wind stress (i-component) (N/m2) at U-point INTEGER , PARAMETER :: jp_vtau = 2 ! index of wind stress (j-component) (N/m2) at V-point INTEGER , PARAMETER :: jp_wndm = 3 ! index of 10m wind module (m/s) at T-point INTEGER , PARAMETER :: jp_humi = 4 ! index of specific humidity ( % ) INTEGER , PARAMETER :: jp_ccov = 5 ! index of cloud cover ( % ) INTEGER , PARAMETER :: jp_tair = 6 ! index of 10m air temperature (Kelvin) INTEGER , PARAMETER :: jp_prec = 7 ! index of total precipitation (rain+snow) (Kg/m2/s) TYPE(FLD),ALLOCATABLE,DIMENSION(:) :: sf ! structure of input fields (file informations, fields read) INTEGER, PARAMETER :: jpintsr = 24 ! number of time step between sunrise and sunset ! ! uses for heat flux computation LOGICAL :: lbulk_init = .TRUE. ! flag, bulk initialization done or not) REAL(wp) :: cai = 1.40e-3 ! best estimate of atm drag in order to get correct FS export in ORCA2-LIM REAL(wp) :: cao = 1.00e-3 ! chosen by default ==> should depends on many things... !!gmto be updated REAL(wp) :: rdtbs2 !: REAL(wp), DIMENSION(19) :: budyko ! BUDYKO's coefficient (cloudiness effect on LW radiation) DATA budyko / 1.00, 0.98, 0.95, 0.92, 0.89, 0.86, 0.83, 0.80, 0.78, 0.75, & & 0.72, 0.69, 0.67, 0.64, 0.61, 0.58, 0.56, 0.53, 0.50 / REAL(wp), DIMENSION(20) :: tauco ! cloud optical depth coefficient DATA tauco / 6.6, 6.6, 7.0, 7.2, 7.1, 6.8, 6.5, 6.6, 7.1, 7.6, & & 6.6, 6.1, 5.6, 5.5, 5.8, 5.8, 5.6, 5.6, 5.6, 5.6 / !! REAL(wp), ALLOCATABLE, SAVE, DIMENSION(:,:) :: sbudyko ! cloudiness effect on LW radiation REAL(wp), ALLOCATABLE, SAVE, DIMENSION(:,:) :: stauc ! cloud optical depth REAL(wp) :: eps20 = 1.e-20 ! constant values !! * Substitutions # include "vectopt_loop_substitute.h90" !!---------------------------------------------------------------------- !! NEMO/OPA 4.0 , NEMO Consortium (2011) !! $Id$ !! Software governed by the CeCILL licence (NEMOGCM/NEMO_CeCILL.txt) !!---------------------------------------------------------------------- CONTAINS SUBROUTINE sbc_blk_clio( kt ) !!--------------------------------------------------------------------- !! *** ROUTINE sbc_blk_clio *** !! !! ** Purpose : provide at each time step the surface ocean fluxes !! (momentum, heat, freshwater and runoff) !! !! ** Method : (1) READ each fluxes in NetCDF files: !! the i-component of the stress (N/m2) !! the j-component of the stress (N/m2) !! the 10m wind speed module (m/s) !! the 10m air temperature (Kelvin) !! the 10m specific humidity (%) !! the cloud cover (%) !! the total precipitation (rain+snow) (Kg/m2/s) !! (2) CALL blk_oce_clio !! !! C A U T I O N : never mask the surface stress fields !! the stress is assumed to be in the (i,j) mesh referential !! !! ** Action : defined at each time-step at the air-sea interface !! - utau, vtau i- and j-component of the wind stress !! - taum wind stress module at T-point !! - wndm 10m wind module at T-point over free ocean or leads in presence of sea-ice !! - qns non-solar heat flux including latent heat of solid !! precip. melting and emp heat content !! - qsr solar heat flux !! - emp upward mass flux (evap. - precip) !! - sfx salt flux; set to zero at nit000 but possibly non-zero !! if ice is present (computed in limsbc(_2).F90) !!---------------------------------------------------------------------- INTEGER, INTENT( in ) :: kt ! ocean time step !! INTEGER :: ifpr, jfpr ! dummy indices INTEGER :: ierr0, ierr1, ierr2, ierr3 ! return error code INTEGER :: ios ! Local integer output status for namelist read !! CHARACTER(len=100) :: cn_dir ! Root directory for location of CLIO files TYPE(FLD_N), DIMENSION(jpfld) :: slf_i ! array of namelist informations on the fields to read TYPE(FLD_N) :: sn_utau, sn_vtau, sn_wndm, sn_tair ! informations about the fields to be read TYPE(FLD_N) :: sn_humi, sn_ccov, sn_prec ! " " !! NAMELIST/namsbc_clio/ cn_dir, sn_utau, sn_vtau, sn_wndm, sn_humi, & & sn_ccov, sn_tair, sn_prec !!--------------------------------------------------------------------- ! ! ====================== ! IF( kt == nit000 ) THEN ! First call kt=nit000 ! ! ! ====================== ! REWIND( numnam_ref ) ! Namelist namsbc_clio in reference namelist : CLIO files READ ( numnam_ref, namsbc_clio, IOSTAT = ios, ERR = 901) 901 IF( ios /= 0 ) CALL ctl_nam ( ios , 'namsbc_clio in reference namelist', lwp ) REWIND( numnam_cfg ) ! Namelist namsbc_clio in configuration namelist : CLIO files READ ( numnam_cfg, namsbc_clio, IOSTAT = ios, ERR = 902 ) 902 IF( ios /= 0 ) CALL ctl_nam ( ios , 'namsbc_clio in configuration namelist', lwp ) IF(lwm) WRITE ( numond, namsbc_clio ) ! store namelist information in an array slf_i(jp_utau) = sn_utau ; slf_i(jp_vtau) = sn_vtau ; slf_i(jp_wndm) = sn_wndm slf_i(jp_tair) = sn_tair ; slf_i(jp_humi) = sn_humi slf_i(jp_ccov) = sn_ccov ; slf_i(jp_prec) = sn_prec ! set sf structure ALLOCATE( sf(jpfld), STAT=ierr0 ) IF( ierr0 > 0 ) CALL ctl_stop( 'STOP', 'sbc_blk_clio: unable to allocate sf structure' ) DO ifpr= 1, jpfld ALLOCATE( sf(ifpr)%fnow(jpi,jpj,1) , STAT=ierr1) IF( slf_i(ifpr)%ln_tint ) ALLOCATE( sf(ifpr)%fdta(jpi,jpj,1,2) , STAT=ierr2 ) END DO IF( ierr1+ierr2 > 0 ) CALL ctl_stop( 'STOP', 'sbc_blk_clio: unable to allocate sf array structure' ) ! fill sf with slf_i and control print CALL fld_fill( sf, slf_i, cn_dir, 'sbc_blk_clio', 'flux formulation for ocean surface boundary condition', 'namsbc_clio' ) ! allocate sbcblk clio arrays ALLOCATE( sbudyko(jpi,jpj) , stauc(jpi,jpj), STAT=ierr3 ) IF( ierr3 > 0 ) CALL ctl_stop( 'STOP', 'sbc_blk_clio: unable to allocate arrays' ) ! sfx(:,:) = 0._wp ! salt flux; zero unless ice is present (computed in limsbc(_2).F90) ! ENDIF ! ! ====================== ! ! ! At each time-step ! ! ! ====================== ! ! CALL fld_read( kt, nn_fsbc, sf ) ! input fields provided at the current time-step ! IF( MOD( kt - 1, nn_fsbc ) == 0 ) CALL blk_oce_clio( sf, sst_m ) ! END SUBROUTINE sbc_blk_clio SUBROUTINE blk_oce_clio( sf, pst ) !!--------------------------------------------------------------------------- !! *** ROUTINE blk_oce_clio *** !! !! ** Purpose : Compute momentum, heat and freshwater fluxes at ocean surface !! using CLIO bulk formulea !! !! ** Method : The flux of heat at the ocean surfaces are derived !! from semi-empirical ( or bulk ) formulae which relate the flux to !! the properties of the surface and of the lower atmosphere. Here, we !! follow the work of Oberhuber, 1988 !! - momentum flux (stresses) directly read in files at U- and V-points !! - compute ocean/ice albedos (call albedo_oce/albedo_ice) !! - compute shortwave radiation for ocean (call blk_clio_qsr_oce) !! - compute long-wave radiation for the ocean !! - compute the turbulent heat fluxes over the ocean !! - deduce the evaporation over the ocean !! ** Action : Fluxes over the ocean: !! - utau, vtau i- and j-component of the wind stress !! - taum wind stress module at T-point !! - wndm 10m wind module at T-point over free ocean or leads in presence of sea-ice !! - qns non-solar heat flux including latent heat of solid !! precip. melting and emp heat content !! - qsr solar heat flux !! - emp suface mass flux (evap.-precip.) !! ** Nota : sf has to be a dummy argument for AGRIF on NEC !!---------------------------------------------------------------------- TYPE(fld), INTENT(in), DIMENSION(:) :: sf ! input data REAL(wp) , INTENT(in), DIMENSION(jpi,jpj) :: pst ! surface temperature [Celcius] !! INTEGER :: ji, jj ! dummy loop indices !! REAL(wp) :: zrhova, zcsho, zcleo, zcldeff ! temporary scalars REAL(wp) :: zqsato, zdteta, zdeltaq, ztvmoy, zobouks ! - - REAL(wp) :: zpsims, zpsihs, zpsils, zobouku, zxins, zpsimu ! - - REAL(wp) :: zpsihu, zpsilu, zstab,zpsim, zpsih, zpsil ! - - REAL(wp) :: zvatmg, zcmn, zchn, zcln, zcmcmn, zdenum ! - - REAL(wp) :: zdtetar, ztvmoyr, zlxins, zchcm, zclcm ! - - REAL(wp) :: zmt1, zmt2, zmt3, ztatm3, ztamr, ztaevbk ! - - REAL(wp) :: zsst, ztatm, zcco1, zpatm, zcmax, zrmax ! - - REAL(wp) :: zrhoa, zev, zes, zeso, zqatm, zevsqr ! - - REAL(wp) :: ztx2, zty2, zcevap, zcprec ! - - REAL(wp), POINTER, DIMENSION(:,:) :: zqlw ! long-wave heat flux over ocean REAL(wp), POINTER, DIMENSION(:,:) :: zqla ! latent heat flux over ocean REAL(wp), POINTER, DIMENSION(:,:) :: zqsb ! sensible heat flux over ocean !!--------------------------------------------------------------------- ! IF( nn_timing == 1 ) CALL timing_start('blk_oce_clio') ! CALL wrk_alloc( jpi,jpj, zqlw, zqla, zqsb ) zpatm = 101000._wp ! atmospheric pressure (assumed constant here) !------------------------------------! ! momentum fluxes (utau, vtau ) ! !------------------------------------! !CDIR COLLAPSE utau(:,:) = sf(jp_utau)%fnow(:,:,1) !CDIR COLLAPSE vtau(:,:) = sf(jp_vtau)%fnow(:,:,1) !------------------------------------! ! wind stress module (taum ) ! !------------------------------------! !CDIR NOVERRCHK DO jj = 2, jpjm1 !CDIR NOVERRCHK DO ji = fs_2, fs_jpim1 ! vector opt. ztx2 = utau(ji-1,jj ) + utau(ji,jj) zty2 = vtau(ji ,jj-1) + vtau(ji,jj) taum(ji,jj) = 0.5 * SQRT( ztx2 * ztx2 + zty2 * zty2 ) END DO END DO utau(:,:) = utau(:,:) * umask(:,:,1) vtau(:,:) = vtau(:,:) * vmask(:,:,1) taum(:,:) = taum(:,:) * tmask(:,:,1) CALL lbc_lnk( taum, 'T', 1. ) !------------------------------------! ! store the wind speed (wndm ) ! !------------------------------------! !CDIR COLLAPSE wndm(:,:) = sf(jp_wndm)%fnow(:,:,1) wndm(:,:) = wndm(:,:) * tmask(:,:,1) !------------------------------------------------! ! Shortwave radiation for ocean and snow/ice ! !------------------------------------------------! CALL blk_clio_qsr_oce( qsr ) qsr(:,:) = qsr(:,:) * tmask(:,:,1) ! no shortwave radiation into the ocean beneath ice shelf !------------------------! ! Other ocean fluxes ! !------------------------! !CDIR NOVERRCHK !CDIR COLLAPSE DO jj = 1, jpj !CDIR NOVERRCHK DO ji = 1, jpi ! zsst = pst(ji,jj) + rt0 ! converte Celcius to Kelvin the SST ztatm = sf(jp_tair)%fnow(ji,jj,1) ! and set minimum value far above 0 K (=rt0 over land) zcco1 = 1.0 - sf(jp_ccov)%fnow(ji,jj,1) ! fraction of clear sky ( 1 - cloud cover) zrhoa = zpatm / ( 287.04 * ztatm ) ! air density (equation of state for dry air) ztamr = ztatm - rtt ! Saturation water vapour zmt1 = SIGN( 17.269, ztamr ) ! || zmt2 = SIGN( 21.875, ztamr ) ! \ / zmt3 = SIGN( 28.200, -ztamr ) ! \/ zes = 611.0 * EXP( ABS( ztamr ) * MIN ( zmt1, zmt2 ) / ( ztatm - 35.86 + MAX( 0.e0, zmt3 ) ) ) zev = sf(jp_humi)%fnow(ji,jj,1) * zes ! vapour pressure zevsqr = SQRT( zev * 0.01 ) ! square-root of vapour pressure zqatm = 0.622 * zev / ( zpatm - 0.378 * zev ) ! specific humidity !--------------------------------------! ! long-wave radiation over the ocean ! ( Berliand 1952 ; all latitudes ) !--------------------------------------! ztatm3 = ztatm * ztatm * ztatm zcldeff = 1.0 - sbudyko(ji,jj) * sf(jp_ccov)%fnow(ji,jj,1) * sf(jp_ccov)%fnow(ji,jj,1) ztaevbk = ztatm * ztatm3 * zcldeff * ( 0.39 - 0.05 * zevsqr ) ! zqlw(ji,jj) = - emic * stefan * ( ztaevbk + 4. * ztatm3 * ( zsst - ztatm ) ) !-------------------------------------------------- ! Latent and sensible heat fluxes over the ocean !-------------------------------------------------- ! ! vapour pressure at saturation of ocean zeso = 611.0 * EXP ( 17.2693884 * ( zsst - rtt ) * tmask(ji,jj,1) / ( zsst - 35.86 ) ) zqsato = ( 0.622 * zeso ) / ( zpatm - 0.378 * zeso ) ! humidity close to the ocean surface (at saturation) ! Drag coefficients from Large and Pond (1981,1982) ! ! Stability parameters zdteta = zsst - ztatm zdeltaq = zqatm - zqsato ztvmoy = ztatm * ( 1. + 2.2e-3 * ztatm * zqatm ) zdenum = MAX( sf(jp_wndm)%fnow(ji,jj,1) * sf(jp_wndm)%fnow(ji,jj,1) * ztvmoy, eps20 ) zdtetar = zdteta / zdenum ztvmoyr = ztvmoy * ztvmoy * zdeltaq / zdenum ! ! case of stable atmospheric conditions zobouks = -70.0 * 10. * ( zdtetar + 3.2e-3 * ztvmoyr ) zobouks = MAX( 0.e0, zobouks ) zpsims = -7.0 * zobouks zpsihs = zpsims zpsils = zpsims ! ! case of unstable atmospheric conditions zobouku = MIN( 0.e0, -100.0 * 10.0 * ( zdtetar + 2.2e-3 * ztvmoyr ) ) zxins = ( 1. - 16. * zobouku )**0.25 zlxins = LOG( ( 1. + zxins * zxins ) / 2. ) zpsimu = 2. * LOG( ( 1 + zxins ) * 0.5 ) + zlxins - 2. * ATAN( zxins ) + rpi * 0.5 zpsihu = 2. * zlxins zpsilu = zpsihu ! ! intermediate values zstab = MAX( 0.e0, SIGN( 1.e0, zdteta ) ) zpsim = zstab * zpsimu + ( 1.0 - zstab ) * zpsims zpsih = zstab * zpsihu + ( 1.0 - zstab ) * zpsihs zpsil = zpsih zvatmg = MAX( 0.032 * 1.5e-3 * sf(jp_wndm)%fnow(ji,jj,1) * sf(jp_wndm)%fnow(ji,jj,1) / grav, eps20 ) zcmn = vkarmn / LOG ( 10. / zvatmg ) zchn = 0.0327 * zcmn zcln = 0.0346 * zcmn zcmcmn = 1. / ( 1. - zcmn * zpsim / vkarmn ) ! sometimes the ratio zchn * zpsih / ( vkarmn * zcmn ) is too close to 1 and zchcm becomes very very big zcmax = 0.1 ! choice for maximum value of the heat transfer coefficient, guided by my intuition zrmax = 1 - 3.e-4 / zcmax ! maximum value of the ratio zchcm = zcmcmn / ( 1. - MIN ( zchn * zpsih / ( vkarmn * zcmn ) , zrmax ) ) zclcm = zchcm ! ! transfert coef. (Large and Pond 1981,1982) zcsho = zchn * zchcm zcleo = zcln * zclcm zrhova = zrhoa * sf(jp_wndm)%fnow(ji,jj,1) ! sensible heat flux zqsb(ji,jj) = zrhova * zcsho * 1004.0 * ( zsst - ztatm ) ! latent heat flux (bounded by zero) zqla(ji,jj) = MAX( 0.e0, zrhova * zcleo * 2.5e+06 * ( zqsato - zqatm ) ) ! END DO END DO ! ----------------------------------------------------------------------------- ! ! III Total FLUXES ! ! ----------------------------------------------------------------------------- ! zcevap = rcp / cevap ! convert zqla ==> evap (Kg/m2/s) ==> m/s ==> W/m2 zcprec = rcp / rday ! convert prec ( mm/day ==> m/s) ==> W/m2 !CDIR COLLAPSE emp(:,:) = zqla(:,:) / cevap & ! freshwater flux & - sf(jp_prec)%fnow(:,:,1) / rday * tmask(:,:,1) ! !CDIR COLLAPSE qns(:,:) = zqlw(:,:) - zqsb(:,:) - zqla(:,:) & ! Downward Non Solar flux & - zqla(:,:) * pst(:,:) * zcevap & ! remove evap. heat content at SST in Celcius & + sf(jp_prec)%fnow(:,:,1) * sf(jp_tair)%fnow(:,:,1) * zcprec ! add precip. heat content at Tair in Celcius qns(:,:) = qns(:,:) * tmask(:,:,1) #if defined key_lim3 qns_oce(:,:) = zqlw(:,:) - zqsb(:,:) - zqla(:,:) qsr_oce(:,:) = qsr(:,:) #endif ! NB: if sea-ice model, the snow precip are computed and the associated heat is added to qns (see blk_ice_clio) IF ( nn_ice == 0 ) THEN CALL iom_put( "qlw_oce" , zqlw ) ! output downward longwave heat over the ocean CALL iom_put( "qsb_oce" , - zqsb ) ! output downward sensible heat over the ocean CALL iom_put( "qla_oce" , - zqla ) ! output downward latent heat over the ocean CALL iom_put( "qemp_oce", qns-zqlw+zqsb+zqla ) ! output downward heat content of E-P over the ocean CALL iom_put( "qns_oce" , qns ) ! output downward non solar heat over the ocean CALL iom_put( "qsr_oce" , qsr ) ! output downward solar heat over the ocean CALL iom_put( "qt_oce" , qns+qsr ) ! output total downward heat over the ocean ENDIF IF(ln_ctl) THEN CALL prt_ctl(tab2d_1=zqsb , clinfo1=' blk_oce_clio: zqsb : ', tab2d_2=zqlw , clinfo2=' zqlw : ') CALL prt_ctl(tab2d_1=zqla , clinfo1=' blk_oce_clio: zqla : ', tab2d_2=qsr , clinfo2=' qsr : ') CALL prt_ctl(tab2d_1=pst , clinfo1=' blk_oce_clio: pst : ', tab2d_2=emp , clinfo2=' emp : ') CALL prt_ctl(tab2d_1=utau , clinfo1=' blk_oce_clio: utau : ', mask1=umask, & & tab2d_2=vtau , clinfo2=' vtau : ', mask2=vmask ) ENDIF CALL wrk_dealloc( jpi,jpj, zqlw, zqla, zqsb ) ! IF( nn_timing == 1 ) CALL timing_stop('blk_oce_clio') ! END SUBROUTINE blk_oce_clio # if defined key_lim2 || defined key_lim3 SUBROUTINE blk_ice_clio_tau !!--------------------------------------------------------------------------- !! *** ROUTINE blk_ice_clio_tau *** !! !! ** Purpose : Computation momentum flux at the ice-atm interface !! !! ** Method : Read utau from a forcing file. Rearrange if C-grid !! !!---------------------------------------------------------------------- REAL(wp) :: zcoef INTEGER :: ji, jj ! dummy loop indices !!--------------------------------------------------------------------- ! IF( nn_timing == 1 ) CALL timing_start('blk_ice_clio_tau') SELECT CASE( cp_ice_msh ) CASE( 'C' ) ! C-grid ice dynamics zcoef = cai / cao ! Change from air-sea stress to air-ice stress utau_ice(:,:) = zcoef * utau(:,:) vtau_ice(:,:) = zcoef * vtau(:,:) CASE( 'I' ) ! I-grid ice dynamics: I-point (i.e. F-point lower-left corner) zcoef = 0.5_wp * cai / cao ! Change from air-sea stress to air-ice stress DO jj = 2, jpj ! stress from ocean U- and V-points to ice U,V point DO ji = 2, jpi ! I-grid : no vector opt. utau_ice(ji,jj) = zcoef * ( utau(ji-1,jj ) + utau(ji-1,jj-1) ) vtau_ice(ji,jj) = zcoef * ( vtau(ji ,jj-1) + vtau(ji-1,jj-1) ) END DO END DO CALL lbc_lnk( utau_ice(:,:), 'I', -1. ) ; CALL lbc_lnk( vtau_ice(:,:), 'I', -1. ) ! I-point END SELECT IF(ln_ctl) THEN CALL prt_ctl(tab2d_1=utau_ice , clinfo1=' blk_ice_clio: utau_ice : ', tab2d_2=vtau_ice , clinfo2=' vtau_ice : ') ENDIF IF( nn_timing == 1 ) CALL timing_stop('blk_ice_clio_tau') END SUBROUTINE blk_ice_clio_tau #endif # if defined key_lim2 || defined key_lim3 SUBROUTINE blk_ice_clio_flx( ptsu , palb_cs, palb_os, palb ) !!--------------------------------------------------------------------------- !! *** ROUTINE blk_ice_clio_flx *** !! !! ** Purpose : Computation of the heat fluxes at ocean and snow/ice !! surface the solar heat at ocean and snow/ice surfaces and the !! sensitivity of total heat fluxes to the SST variations !! !! ** Method : The flux of heat at the ice and ocean surfaces are derived !! from semi-empirical ( or bulk ) formulae which relate the flux to !! the properties of the surface and of the lower atmosphere. Here, we !! follow the work of Oberhuber, 1988 !! !! ** Action : call albedo_oce/albedo_ice to compute ocean/ice albedo !! - snow precipitation !! - solar flux at the ocean and ice surfaces !! - the long-wave radiation for the ocean and sea/ice !! - turbulent heat fluxes over water and ice !! - evaporation over water !! - total heat fluxes sensitivity over ice (dQ/dT) !! - latent heat flux sensitivity over ice (dQla/dT) !! - qns : modified the non solar heat flux over the ocean !! to take into account solid precip latent heat flux !!---------------------------------------------------------------------- REAL(wp), INTENT(in ), DIMENSION(:,:,:) :: ptsu ! ice surface temperature [Kelvin] REAL(wp), INTENT(in ), DIMENSION(:,:,:) :: palb_cs ! ice albedo (clear sky) (alb_ice_cs) [-] REAL(wp), INTENT(in ), DIMENSION(:,:,:) :: palb_os ! ice albedo (overcast sky) (alb_ice_os) [-] REAL(wp), INTENT( out), DIMENSION(:,:,:) :: palb ! ice albedo (actual value) [-] !! INTEGER :: ji, jj, jl ! dummy loop indices !! REAL(wp) :: zmt1, zmt2, zmt3, ztatm3 ! temporary scalars REAL(wp) :: ztaevbk, zind1, zind2, zind3, ztamr ! - - REAL(wp) :: zesi, zqsati, zdesidt ! - - REAL(wp) :: zdqla, zcldeff, zev, zes, zpatm, zrhova ! - - REAL(wp) :: zcshi, zclei, zrhovaclei, zrhovacshi ! - - REAL(wp) :: ztice3, zticemb, zticemb2, zdqlw, zdqsb ! - - REAL(wp) :: z1_lsub ! - - !! REAL(wp), DIMENSION(:,:) , POINTER :: ztatm ! Tair in Kelvin REAL(wp), DIMENSION(:,:) , POINTER :: zqatm ! specific humidity REAL(wp), DIMENSION(:,:) , POINTER :: zevsqr ! vapour pressure square-root REAL(wp), DIMENSION(:,:) , POINTER :: zrhoa ! air density REAL(wp), DIMENSION(:,:,:), POINTER :: z_qlw, z_qsb REAL(wp), DIMENSION(:,:) , POINTER :: zevap, zsnw !!--------------------------------------------------------------------- ! IF( nn_timing == 1 ) CALL timing_start('blk_ice_clio_flx') ! CALL wrk_alloc( jpi,jpj, ztatm, zqatm, zevsqr, zrhoa ) CALL wrk_alloc( jpi,jpj, jpl, z_qlw, z_qsb ) zpatm = 101000. ! atmospheric pressure (assumed constant here) !-------------------------------------------------------------------------------- ! Determine cloud optical depths as a function of latitude (Chou et al., 1981). ! and the correction factor for taking into account the effect of clouds !-------------------------------------------------------------------------------- !CDIR NOVERRCHK !CDIR COLLAPSE DO jj = 1, jpj !CDIR NOVERRCHK DO ji = 1, jpi ztatm (ji,jj) = sf(jp_tair)%fnow(ji,jj,1) ! air temperature in Kelvins zrhoa(ji,jj) = zpatm / ( 287.04 * ztatm(ji,jj) ) ! air density (equation of state for dry air) ztamr = ztatm(ji,jj) - rtt ! Saturation water vapour zmt1 = SIGN( 17.269, ztamr ) zmt2 = SIGN( 21.875, ztamr ) zmt3 = SIGN( 28.200, -ztamr ) zes = 611.0 * EXP( ABS( ztamr ) * MIN ( zmt1, zmt2 ) & & / ( ztatm(ji,jj) - 35.86 + MAX( 0.e0, zmt3 ) ) ) zev = sf(jp_humi)%fnow(ji,jj,1) * zes ! vapour pressure zevsqr(ji,jj) = SQRT( zev * 0.01 ) ! square-root of vapour pressure zqatm(ji,jj) = 0.622 * zev / ( zpatm - 0.378 * zev ) ! specific humidity !---------------------------------------------------- ! Computation of snow precipitation (Ledley, 1985) | !---------------------------------------------------- zmt1 = 253.0 - ztatm(ji,jj) ; zind1 = MAX( 0.e0, SIGN( 1.e0, zmt1 ) ) zmt2 = ( 272.0 - ztatm(ji,jj) ) / 38.0 ; zind2 = MAX( 0.e0, SIGN( 1.e0, zmt2 ) ) zmt3 = ( 281.0 - ztatm(ji,jj) ) / 18.0 ; zind3 = MAX( 0.e0, SIGN( 1.e0, zmt3 ) ) sprecip(ji,jj) = sf(jp_prec)%fnow(ji,jj,1) / rday & ! rday = converte mm/day to kg/m2/s & * ( zind1 & ! solid (snow) precipitation [kg/m2/s] & + ( 1.0 - zind1 ) * ( zind2 * ( 0.5 + zmt2 ) & & + ( 1.0 - zind2 ) * zind3 * zmt3 ) ) !----------------------------------------------------! ! fraction of net penetrative shortwave radiation ! !----------------------------------------------------! ! fraction of qsr_ice which is NOT absorbed in the thin surface layer ! and thus which penetrates inside the ice cover ( Maykut and Untersteiner, 1971 ; Elbert anbd Curry, 1993 ) fr1_i0(ji,jj) = 0.18 * ( 1.e0 - sf(jp_ccov)%fnow(ji,jj,1) ) + 0.35 * sf(jp_ccov)%fnow(ji,jj,1) fr2_i0(ji,jj) = 0.82 * ( 1.e0 - sf(jp_ccov)%fnow(ji,jj,1) ) + 0.65 * sf(jp_ccov)%fnow(ji,jj,1) END DO END DO CALL iom_put( 'snowpre', sprecip ) ! Snow precipitation !-----------------------------------------------------------! ! snow/ice Shortwave radiation (abedo already computed) ! !-----------------------------------------------------------! CALL blk_clio_qsr_ice( palb_cs, palb_os, qsr_ice ) DO jl = 1, jpl palb(:,:,jl) = ( palb_cs(:,:,jl) * ( 1.e0 - sf(jp_ccov)%fnow(:,:,1) ) & & + palb_os(:,:,jl) * sf(jp_ccov)%fnow(:,:,1) ) END DO ! ! ========================== ! DO jl = 1, jpl ! Loop over ice categories ! ! ! ========================== ! !CDIR NOVERRCHK !CDIR COLLAPSE DO jj = 1 , jpj !CDIR NOVERRCHK DO ji = 1, jpi !-------------------------------------------! ! long-wave radiation over ice categories ! ( Berliand 1952 ; all latitudes ) !-------------------------------------------! ztatm3 = ztatm(ji,jj) * ztatm(ji,jj) * ztatm(ji,jj) zcldeff = 1.0 - sbudyko(ji,jj) * sf(jp_ccov)%fnow(ji,jj,1) * sf(jp_ccov)%fnow(ji,jj,1) ztaevbk = ztatm3 * ztatm(ji,jj) * zcldeff * ( 0.39 - 0.05 * zevsqr(ji,jj) ) ! z_qlw(ji,jj,jl) = - emic * stefan * ( ztaevbk + 4. * ztatm3 * ( ptsu(ji,jj,jl) - ztatm(ji,jj) ) ) !---------------------------------------- ! Turbulent heat fluxes over snow/ice ( Latent and sensible ) !---------------------------------------- ! vapour pressure at saturation of ice (tmask to avoid overflow in the exponential) zesi = 611.0 * EXP( 21.8745587 * tmask(ji,jj,1) * ( ptsu(ji,jj,jl) - rtt )/ ( ptsu(ji,jj,jl) - 7.66 ) ) ! humidity close to the ice surface (at saturation) zqsati = ( 0.622 * zesi ) / ( zpatm - 0.378 * zesi ) ! computation of intermediate values zticemb = ptsu(ji,jj,jl) - 7.66 zticemb2 = zticemb * zticemb ztice3 = ptsu(ji,jj,jl) * ptsu(ji,jj,jl) * ptsu(ji,jj,jl) zdesidt = zesi * ( 9.5 * LOG( 10.0 ) * ( rtt - 7.66 ) / zticemb2 ) ! Transfer cofficients assumed to be constant (Parkinson 1979 ; Maykut 1982) zcshi = 1.75e-03 zclei = zcshi ! sensible and latent fluxes over ice zrhova = zrhoa(ji,jj) * sf(jp_wndm)%fnow(ji,jj,1) ! computation of intermediate values zrhovaclei = zrhova * zcshi * 2.834e+06 zrhovacshi = zrhova * zclei * 1004.0 ! sensible heat flux z_qsb(ji,jj,jl) = zrhovacshi * ( ptsu(ji,jj,jl) - ztatm(ji,jj) ) ! latent heat flux qla_ice(ji,jj,jl) = MAX( 0.e0, zrhovaclei * ( zqsati - zqatm(ji,jj) ) ) ! sensitivity of non solar fluxes (dQ/dT) (long-wave, sensible and latent fluxes) zdqlw = 4.0 * emic * stefan * ztice3 zdqsb = zrhovacshi zdqla = zrhovaclei * ( zdesidt * ( zqsati * zqsati / ( zesi * zesi ) ) * ( zpatm / 0.622 ) ) ! dqla_ice(ji,jj,jl) = zdqla ! latent flux sensitivity dqns_ice(ji,jj,jl) = -( zdqlw + zdqsb + zdqla ) ! total non solar sensitivity END DO ! END DO ! END DO ! ! ----------------------------------------------------------------------------- ! ! Total FLUXES ! ! ----------------------------------------------------------------------------- ! ! !CDIR COLLAPSE qns_ice(:,:,:) = z_qlw (:,:,:) - z_qsb (:,:,:) - qla_ice (:,:,:) ! Downward Non Solar flux !CDIR COLLAPSE tprecip(:,:) = sf(jp_prec)%fnow(:,:,1) / rday ! total precipitation [kg/m2/s] ! ! ----------------------------------------------------------------------------- ! ! Correct the OCEAN non solar flux with the existence of solid precipitation ! ! ---------------=====--------------------------------------------------------- ! !CDIR COLLAPSE qns(:,:) = qns(:,:) & ! update the non-solar heat flux with: & - sprecip(:,:) * lfus & ! remove melting solid precip & + sprecip(:,:) * MIN( sf(jp_tair)%fnow(:,:,1), rt0_snow - rt0 ) * cpic & ! add solid P at least below melting & - sprecip(:,:) * sf(jp_tair)%fnow(:,:,1) * rcp ! remove solid precip. at Tair #if defined key_lim3 ! ----------------------------------------------------------------------------- ! ! Distribute evapo, precip & associated heat over ice and ocean ! ---------------=====--------------------------------------------------------- ! CALL wrk_alloc( jpi,jpj, zevap, zsnw ) ! --- evaporation --- ! z1_lsub = 1._wp / Lsub evap_ice (:,:,:) = qla_ice (:,:,:) * z1_lsub ! sublimation devap_ice(:,:,:) = dqla_ice(:,:,:) * z1_lsub zevap (:,:) = emp(:,:) + tprecip(:,:) ! evaporation over ocean ! --- evaporation minus precipitation --- ! CALL lim_thd_snwblow( pfrld, zsnw ) ! snow redistribution by wind emp_oce(:,:) = pfrld(:,:) * zevap(:,:) - ( tprecip(:,:) - sprecip(:,:) ) - sprecip(:,:) * ( 1._wp - zsnw ) emp_ice(:,:) = SUM( a_i_b(:,:,:) * evap_ice(:,:,:), dim=3 ) - sprecip(:,:) * zsnw emp_tot(:,:) = emp_oce(:,:) + emp_ice(:,:) ! --- heat flux associated with emp --- ! qemp_oce(:,:) = - pfrld(:,:) * zevap(:,:) * sst_m(:,:) * rcp & ! evap & + ( tprecip(:,:) - sprecip(:,:) ) * ( sf(jp_tair)%fnow(:,:,1) - rt0 ) * rcp & ! liquid precip & + sprecip(:,:) * ( 1._wp - zsnw ) * & ! solid precip & ( ( MIN( sf(jp_tair)%fnow(:,:,1), rt0_snow ) - rt0 ) * cpic * tmask(:,:,1) - lfus ) qemp_ice(:,:) = sprecip(:,:) * zsnw * & ! solid precip (only) & ( ( MIN( sf(jp_tair)%fnow(:,:,1), rt0_snow ) - rt0 ) * cpic * tmask(:,:,1) - lfus ) ! --- total solar and non solar fluxes --- ! qns_tot(:,:) = pfrld(:,:) * qns_oce(:,:) + SUM( a_i_b(:,:,:) * qns_ice(:,:,:), dim=3 ) + qemp_ice(:,:) + qemp_oce(:,:) qsr_tot(:,:) = pfrld(:,:) * qsr_oce(:,:) + SUM( a_i_b(:,:,:) * qsr_ice(:,:,:), dim=3 ) ! --- heat content of precip over ice in J/m3 (to be used in 1D-thermo) --- ! qprec_ice(:,:) = rhosn * ( ( MIN( sf(jp_tair)%fnow(:,:,1), rt0_snow ) - rt0 ) * cpic * tmask(:,:,1) - lfus ) CALL wrk_dealloc( jpi,jpj, zevap, zsnw ) #endif !!gm : not necessary as all input data are lbc_lnk... CALL lbc_lnk( fr1_i0 (:,:) , 'T', 1. ) CALL lbc_lnk( fr2_i0 (:,:) , 'T', 1. ) DO jl = 1, jpl CALL lbc_lnk( qns_ice (:,:,jl) , 'T', 1. ) CALL lbc_lnk( dqns_ice(:,:,jl) , 'T', 1. ) CALL lbc_lnk( qla_ice (:,:,jl) , 'T', 1. ) CALL lbc_lnk( dqla_ice(:,:,jl) , 'T', 1. ) END DO !!gm : mask is not required on forcing DO jl = 1, jpl qns_ice (:,:,jl) = qns_ice (:,:,jl) * tmask(:,:,1) qla_ice (:,:,jl) = qla_ice (:,:,jl) * tmask(:,:,1) dqns_ice(:,:,jl) = dqns_ice(:,:,jl) * tmask(:,:,1) dqla_ice(:,:,jl) = dqla_ice(:,:,jl) * tmask(:,:,1) END DO CALL wrk_dealloc( jpi,jpj, ztatm, zqatm, zevsqr, zrhoa ) CALL wrk_dealloc( jpi,jpj, jpl , z_qlw, z_qsb ) IF(ln_ctl) THEN CALL prt_ctl(tab3d_1=z_qsb , clinfo1=' blk_ice_clio: z_qsb : ', tab3d_2=z_qlw , clinfo2=' z_qlw : ', kdim=jpl) CALL prt_ctl(tab3d_1=qla_ice , clinfo1=' blk_ice_clio: z_qla : ', tab3d_2=qsr_ice , clinfo2=' qsr_ice : ', kdim=jpl) CALL prt_ctl(tab3d_1=dqns_ice , clinfo1=' blk_ice_clio: dqns_ice : ', tab3d_2=qns_ice , clinfo2=' qns_ice : ', kdim=jpl) CALL prt_ctl(tab3d_1=dqla_ice , clinfo1=' blk_ice_clio: dqla_ice : ', tab3d_2=ptsu , clinfo2=' ptsu : ', kdim=jpl) CALL prt_ctl(tab2d_1=tprecip , clinfo1=' blk_ice_clio: tprecip : ', tab2d_2=sprecip , clinfo2=' sprecip : ') ENDIF IF( nn_timing == 1 ) CALL timing_stop('blk_ice_clio_flx') ! END SUBROUTINE blk_ice_clio_flx #endif SUBROUTINE blk_clio_qsr_oce( pqsr_oce ) !!--------------------------------------------------------------------------- !! *** ROUTINE blk_clio_qsr_oce *** !! !! ** Purpose : Computation of the shortwave radiation at the ocean and the !! snow/ice surfaces. !! !! ** Method : - computed qsr from the cloud cover for both ice and ocean !! - also initialise sbudyko and stauc once for all !!---------------------------------------------------------------------- REAL(wp), INTENT( out), DIMENSION(jpi,jpj) :: pqsr_oce ! shortwave radiation over the ocean !! INTEGER, PARAMETER :: jp24 = 24 ! sampling of the daylight period (sunrise to sunset) into 24 equal parts !! INTEGER :: ji, jj, jt ! dummy loop indices INTEGER :: indaet ! = -1, 0, 1 for odd, normal and leap years resp. INTEGER :: iday ! integer part of day INTEGER :: indxb, indxc ! index for cloud depth coefficient REAL(wp) :: zalat , zclat, zcmue, zcmue2 ! local scalars REAL(wp) :: zmt1, zmt2, zmt3 ! REAL(wp) :: zdecl, zsdecl , zcdecl ! REAL(wp) :: za_oce, ztamr ! REAL(wp) :: zdl, zlha ! local scalars REAL(wp) :: zlmunoon, zcldcor, zdaycor ! REAL(wp) :: zxday, zdist, zcoef, zcoef1 ! REAL(wp) :: zes REAL(wp), DIMENSION(:,:), POINTER :: zev ! vapour pressure REAL(wp), DIMENSION(:,:), POINTER :: zdlha, zlsrise, zlsset ! 2D workspace REAL(wp), DIMENSION(:,:), POINTER :: zps, zpc ! sine (cosine) of latitude per sine (cosine) of solar declination !!--------------------------------------------------------------------- ! IF( nn_timing == 1 ) CALL timing_start('blk_clio_qsr_oce') ! CALL wrk_alloc( jpi,jpj, zev, zdlha, zlsrise, zlsset, zps, zpc ) IF( lbulk_init ) THEN ! Initilization at first time step only rdtbs2 = nn_fsbc * rdt * 0.5 ! cloud optical depths as a function of latitude (Chou et al., 1981). ! and the correction factor for taking into account the effect of clouds DO jj = 1, jpj DO ji = 1 , jpi zalat = ( 90.e0 - ABS( gphit(ji,jj) ) ) / 5.e0 zclat = ( 95.e0 - gphit(ji,jj) ) / 10.e0 indxb = 1 + INT( zalat ) indxc = 1 + INT( zclat ) zdl = zclat - INT( zclat ) ! correction factor to account for the effect of clouds sbudyko(ji,jj) = budyko(indxb) stauc (ji,jj) = ( 1.e0 - zdl ) * tauco( indxc ) + zdl * tauco( indxc + 1 ) END DO END DO lbulk_init = .FALSE. ENDIF ! Saturated water vapour and vapour pressure ! ------------------------------------------ !CDIR NOVERRCHK !CDIR COLLAPSE DO jj = 1, jpj !CDIR NOVERRCHK DO ji = 1, jpi ztamr = sf(jp_tair)%fnow(ji,jj,1) - rtt zmt1 = SIGN( 17.269, ztamr ) zmt2 = SIGN( 21.875, ztamr ) zmt3 = SIGN( 28.200, -ztamr ) zes = 611.0 * EXP( ABS( ztamr ) * MIN ( zmt1, zmt2 ) & ! Saturation water vapour & / ( sf(jp_tair)%fnow(ji,jj,1) - 35.86 + MAX( 0.e0, zmt3 ) ) ) zev(ji,jj) = sf(jp_humi)%fnow(ji,jj,1) * zes * 1.0e-05 ! vapour pressure END DO END DO !-----------------------------------! ! Computation of solar irradiance ! !-----------------------------------! !!gm : hard coded leap year ??? indaet = 1 ! = -1, 0, 1 for odd, normal and leap years resp. zxday = nday_year + rdtbs2 / rday ! day of the year at which the fluxes are calculated iday = INT( zxday ) ! (centred at the middle of the ice time step) CALL flx_blk_declin( indaet, iday, zdecl ) ! solar declination of the current day zsdecl = SIN( zdecl * rad ) ! its sine zcdecl = COS( zdecl * rad ) ! its cosine ! correction factor added for computation of shortwave flux to take into account the variation of ! the distance between the sun and the earth during the year (Oberhuber 1988) zdist = zxday * 2. * rpi / REAL(nyear_len(1), wp) zdaycor = 1.0 + 0.0013 * SIN( zdist ) + 0.0342 * COS( zdist ) !CDIR NOVERRCHK DO jj = 1, jpj !CDIR NOVERRCHK DO ji = 1, jpi ! product of sine (cosine) of latitude and sine (cosine) of solar declination zps(ji,jj) = SIN( gphit(ji,jj) * rad ) * zsdecl zpc(ji,jj) = COS( gphit(ji,jj) * rad ) * zcdecl ! computation of the both local time of sunrise and sunset zlsrise(ji,jj) = ACOS( - SIGN( 1.e0, zps(ji,jj) ) & & * MIN( 1.e0, SIGN( 1.e0, zps(ji,jj) ) * ( zps(ji,jj) / zpc(ji,jj) ) ) ) zlsset (ji,jj) = - zlsrise(ji,jj) ! dividing the solar day into jp24 segments of length zdlha zdlha (ji,jj) = ( zlsrise(ji,jj) - zlsset(ji,jj) ) / REAL( jp24, wp ) END DO END DO !---------------------------------------------! ! shortwave radiation absorbed by the ocean ! !---------------------------------------------! pqsr_oce(:,:) = 0.e0 ! set ocean qsr to zero ! compute and sum ocean qsr over the daylight (i.e. between sunrise and sunset) !CDIR NOVERRCHK DO jt = 1, jp24 zcoef = FLOAT( jt ) - 0.5 !CDIR NOVERRCHK !CDIR COLLAPSE DO jj = 1, jpj !CDIR NOVERRCHK DO ji = 1, jpi zlha = COS( zlsrise(ji,jj) - zcoef * zdlha(ji,jj) ) ! local hour angle zcmue = MAX( 0.e0 , zps(ji,jj) + zpc(ji,jj) * zlha ) ! cos of local solar altitude zcmue2 = 1368.0 * zcmue * zcmue ! ocean albedo depending on the cloud cover (Payne, 1972) za_oce = ( 1.0 - sf(jp_ccov)%fnow(ji,jj,1) ) * 0.05 / ( 1.1 * zcmue**1.4 + 0.15 ) & ! clear sky & + sf(jp_ccov)%fnow(ji,jj,1) * 0.06 ! overcast ! solar heat flux absorbed by the ocean (Zillman, 1972) pqsr_oce(ji,jj) = pqsr_oce(ji,jj) & & + ( 1.0 - za_oce ) * zdlha(ji,jj) * zcmue2 & & / ( ( zcmue + 2.7 ) * zev(ji,jj) + 1.085 * zcmue + 0.10 ) END DO END DO END DO ! Taking into account the ellipsity of the earth orbit, the clouds AND masked if sea-ice cover > 0% zcoef1 = srgamma * zdaycor / ( 2. * rpi ) !CDIR COLLAPSE DO jj = 1, jpj DO ji = 1, jpi zlmunoon = ASIN( zps(ji,jj) + zpc(ji,jj) ) / rad ! local noon solar altitude zcldcor = MIN( 1.e0, ( 1.e0 - 0.62 * sf(jp_ccov)%fnow(ji,jj,1) & ! cloud correction (Reed 1977) & + 0.0019 * zlmunoon ) ) pqsr_oce(ji,jj) = zcoef1 * zcldcor * pqsr_oce(ji,jj) * tmask(ji,jj,1) ! and zcoef1: ellipsity END DO END DO CALL wrk_dealloc( jpi,jpj, zev, zdlha, zlsrise, zlsset, zps, zpc ) ! IF( nn_timing == 1 ) CALL timing_stop('blk_clio_qsr_oce') ! END SUBROUTINE blk_clio_qsr_oce SUBROUTINE blk_clio_qsr_ice( pa_ice_cs, pa_ice_os, pqsr_ice ) !!--------------------------------------------------------------------------- !! *** ROUTINE blk_clio_qsr_ice *** !! !! ** Purpose : Computation of the shortwave radiation at the ocean and the !! snow/ice surfaces. !! !! ** Method : - computed qsr from the cloud cover for both ice and ocean !! - also initialise sbudyko and stauc once for all !!---------------------------------------------------------------------- REAL(wp), INTENT(in ), DIMENSION(:,:,:) :: pa_ice_cs ! albedo of ice under clear sky REAL(wp), INTENT(in ), DIMENSION(:,:,:) :: pa_ice_os ! albedo of ice under overcast sky REAL(wp), INTENT( out), DIMENSION(:,:,:) :: pqsr_ice ! shortwave radiation over the ice/snow !! INTEGER, PARAMETER :: jp24 = 24 ! sampling of the daylight period (sunrise to sunset) into 24 equal parts !! INTEGER :: ji, jj, jl, jt ! dummy loop indices INTEGER :: ijpl ! number of ice categories (3rd dim of pqsr_ice) INTEGER :: indaet ! = -1, 0, 1 for odd, normal and leap years resp. INTEGER :: iday ! integer part of day !! REAL(wp) :: zcmue, zcmue2, ztamr ! temporary scalars REAL(wp) :: zmt1, zmt2, zmt3 ! - - REAL(wp) :: zdecl, zsdecl, zcdecl ! - - REAL(wp) :: zlha, zdaycor, zes ! - - REAL(wp) :: zxday, zdist, zcoef, zcoef1 ! - - REAL(wp) :: zqsr_ice_cs, zqsr_ice_os ! - - REAL(wp), DIMENSION(:,:), POINTER :: zev ! vapour pressure REAL(wp), DIMENSION(:,:), POINTER :: zdlha, zlsrise, zlsset ! 2D workspace REAL(wp), DIMENSION(:,:), POINTER :: zps, zpc ! sine (cosine) of latitude per sine (cosine) of solar declination !!--------------------------------------------------------------------- ! IF( nn_timing == 1 ) CALL timing_start('blk_clio_qsr_ice') ! CALL wrk_alloc( jpi,jpj, zev, zdlha, zlsrise, zlsset, zps, zpc ) ijpl = SIZE(pqsr_ice, 3 ) ! number of ice categories ! Saturated water vapour and vapour pressure ! ------------------------------------------ !CDIR NOVERRCHK !CDIR COLLAPSE DO jj = 1, jpj !CDIR NOVERRCHK DO ji = 1, jpi ztamr = sf(jp_tair)%fnow(ji,jj,1) - rtt zmt1 = SIGN( 17.269, ztamr ) zmt2 = SIGN( 21.875, ztamr ) zmt3 = SIGN( 28.200, -ztamr ) zes = 611.0 * EXP( ABS( ztamr ) * MIN ( zmt1, zmt2 ) & ! Saturation water vapour & / ( sf(jp_tair)%fnow(ji,jj,1) - 35.86 + MAX( 0.e0, zmt3 ) ) ) zev(ji,jj) = sf(jp_humi)%fnow(ji,jj,1) * zes * 1.0e-05 ! vapour pressure END DO END DO !-----------------------------------! ! Computation of solar irradiance ! !-----------------------------------! !!gm : hard coded leap year ??? indaet = 1 ! = -1, 0, 1 for odd, normal and leap years resp. zxday = nday_year + rdtbs2 / rday ! day of the year at which the fluxes are calculated iday = INT( zxday ) ! (centred at the middle of the ice time step) CALL flx_blk_declin( indaet, iday, zdecl ) ! solar declination of the current day zsdecl = SIN( zdecl * rad ) ! its sine zcdecl = COS( zdecl * rad ) ! its cosine ! correction factor added for computation of shortwave flux to take into account the variation of ! the distance between the sun and the earth during the year (Oberhuber 1988) zdist = zxday * 2. * rpi / REAL(nyear_len(1), wp) zdaycor = 1.0 + 0.0013 * SIN( zdist ) + 0.0342 * COS( zdist ) !CDIR NOVERRCHK DO jj = 1, jpj !CDIR NOVERRCHK DO ji = 1, jpi ! product of sine (cosine) of latitude and sine (cosine) of solar declination zps(ji,jj) = SIN( gphit(ji,jj) * rad ) * zsdecl zpc(ji,jj) = COS( gphit(ji,jj) * rad ) * zcdecl ! computation of the both local time of sunrise and sunset zlsrise(ji,jj) = ACOS( - SIGN( 1.e0, zps(ji,jj) ) & & * MIN( 1.e0, SIGN( 1.e0, zps(ji,jj) ) * ( zps(ji,jj) / zpc(ji,jj) ) ) ) zlsset (ji,jj) = - zlsrise(ji,jj) ! dividing the solar day into jp24 segments of length zdlha zdlha (ji,jj) = ( zlsrise(ji,jj) - zlsset(ji,jj) ) / REAL( jp24, wp ) END DO END DO !---------------------------------------------! ! shortwave radiation absorbed by the ice ! !---------------------------------------------! ! compute and sum ice qsr over the daylight for each ice categories pqsr_ice(:,:,:) = 0.e0 zcoef1 = zdaycor / ( 2. * rpi ) ! Correction for the ellipsity of the earth orbit ! !----------------------------! DO jl = 1, ijpl ! loop over ice categories ! ! !----------------------------! !CDIR NOVERRCHK DO jt = 1, jp24 zcoef = FLOAT( jt ) - 0.5 !CDIR NOVERRCHK !CDIR COLLAPSE DO jj = 1, jpj !CDIR NOVERRCHK DO ji = 1, jpi zlha = COS( zlsrise(ji,jj) - zcoef * zdlha(ji,jj) ) ! local hour angle zcmue = MAX( 0.e0 , zps(ji,jj) + zpc(ji,jj) * zlha ) ! cos of local solar altitude zcmue2 = 1368.0 * zcmue * zcmue ! solar heat flux absorbed by the ice/snow system (Shine and Crane 1984 adapted to high albedo) zqsr_ice_cs = ( 1.0 - pa_ice_cs(ji,jj,jl) ) * zdlha(ji,jj) * zcmue2 & ! clear sky & / ( ( 1.0 + zcmue ) * zev(ji,jj) + 1.2 * zcmue + 0.0455 ) zqsr_ice_os = zdlha(ji,jj) * SQRT( zcmue ) & ! overcast sky & * ( 53.5 + 1274.5 * zcmue ) * ( 1.0 - 0.996 * pa_ice_os(ji,jj,jl) ) & & / ( 1.0 + 0.139 * stauc(ji,jj) * ( 1.0 - 0.9435 * pa_ice_os(ji,jj,jl) ) ) pqsr_ice(ji,jj,jl) = pqsr_ice(ji,jj,jl) + ( ( 1.0 - sf(jp_ccov)%fnow(ji,jj,1) ) * zqsr_ice_cs & & + sf(jp_ccov)%fnow(ji,jj,1) * zqsr_ice_os ) END DO END DO END DO ! ! Correction : Taking into account the ellipsity of the earth orbit pqsr_ice(:,:,jl) = pqsr_ice(:,:,jl) * zcoef1 * tmask(:,:,1) ! ! !--------------------------------! END DO ! end loop over ice categories ! ! !--------------------------------! !!gm : this should be suppress as input data have been passed through lbc_lnk DO jl = 1, ijpl CALL lbc_lnk( pqsr_ice(:,:,jl) , 'T', 1. ) END DO ! CALL wrk_dealloc( jpi,jpj, zev, zdlha, zlsrise, zlsset, zps, zpc ) ! IF( nn_timing == 1 ) CALL timing_stop('blk_clio_qsr_ice') ! END SUBROUTINE blk_clio_qsr_ice SUBROUTINE flx_blk_declin( ky, kday, pdecl ) !!--------------------------------------------------------------------------- !! *** ROUTINE flx_blk_declin *** !! !! ** Purpose : Computation of the solar declination for the day !! !! ** Method : ??? !!--------------------------------------------------------------------- INTEGER , INTENT(in ) :: ky ! = -1, 0, 1 for odd, normal and leap years resp. INTEGER , INTENT(in ) :: kday ! day of the year ( kday = 1 on january 1) REAL(wp), INTENT( out) :: pdecl ! solar declination !! REAL(wp) :: a0 = 0.39507671 ! coefficients for solar declinaison computation REAL(wp) :: a1 = 22.85684301 ! " "" " REAL(wp) :: a2 = -0.38637317 ! " "" " REAL(wp) :: a3 = 0.15096535 ! " "" " REAL(wp) :: a4 = -0.00961411 ! " "" " REAL(wp) :: b1 = -4.29692073 ! " "" " REAL(wp) :: b2 = 0.05702074 ! " "" " REAL(wp) :: b3 = -0.09028607 ! " "" " REAL(wp) :: b4 = 0.00592797 !! REAL(wp) :: zday ! corresponding day of type year (cf. ky) REAL(wp) :: zp ! temporary scalars !!--------------------------------------------------------------------- IF ( ky == 1 ) THEN ; zday = REAL( kday, wp ) - 0.5 ELSEIF( ky == 3 ) THEN ; zday = REAL( kday, wp ) - 1. ELSE ; zday = REAL( kday, wp ) ENDIF zp = rpi * ( 2.0 * zday - 367.0 ) / REAL(nyear_len(1), wp) pdecl = a0 & & + a1 * COS( zp ) + a2 * COS( 2. * zp ) + a3 * COS( 3. * zp ) + a4 * COS( 4. * zp ) & & + b1 * SIN( zp ) + b2 * SIN( 2. * zp ) + b3 * SIN( 3. * zp ) + b4 * SIN( 4. * zp ) ! END SUBROUTINE flx_blk_declin !!====================================================================== END MODULE sbcblk_clio