| 1 | MODULE sbcice_if |
|---|
| 2 | !!====================================================================== |
|---|
| 3 | !! *** MODULE sbcice *** |
|---|
| 4 | !! Surface module : update surface ocean boundary condition over ice |
|---|
| 5 | !! covered area using ice-if model |
|---|
| 6 | !!====================================================================== |
|---|
| 7 | !! History : 3.0 ! 2006-06 (G. Madec) Original code |
|---|
| 8 | !!---------------------------------------------------------------------- |
|---|
| 9 | |
|---|
| 10 | !!---------------------------------------------------------------------- |
|---|
| 11 | !! sbc_ice_if : update sbc in ice-covered area |
|---|
| 12 | !!---------------------------------------------------------------------- |
|---|
| 13 | USE oce ! ocean dynamics and tracers |
|---|
| 14 | USE dom_oce ! ocean space and time domain |
|---|
| 15 | USE phycst ! physical constants |
|---|
| 16 | USE eosbn2 ! equation of state |
|---|
| 17 | USE sbc_oce ! surface boundary condition: ocean fields |
|---|
| 18 | #if defined key_si3 |
|---|
| 19 | USE ice , ONLY : a_i |
|---|
| 20 | #else |
|---|
| 21 | USE sbc_ice , ONLY : a_i |
|---|
| 22 | #endif |
|---|
| 23 | ! |
|---|
| 24 | USE in_out_manager ! I/O manager |
|---|
| 25 | USE iom ! I/O manager library |
|---|
| 26 | USE fldread ! read input field |
|---|
| 27 | USE lib_mpp ! MPP library |
|---|
| 28 | USE lib_fortran ! Fortran utilities (allows no signed zero when 'key_nosignedzero' defined) |
|---|
| 29 | |
|---|
| 30 | IMPLICIT NONE |
|---|
| 31 | PRIVATE |
|---|
| 32 | |
|---|
| 33 | PUBLIC sbc_ice_if ! routine called in sbcmod |
|---|
| 34 | |
|---|
| 35 | TYPE(FLD), ALLOCATABLE, DIMENSION(:) :: sf_ice ! structure of input ice-cover (file informations, fields read) |
|---|
| 36 | |
|---|
| 37 | !!---------------------------------------------------------------------- |
|---|
| 38 | !! NEMO/OCE 4.0 , NEMO Consortium (2018) |
|---|
| 39 | !! $Id$ |
|---|
| 40 | !! Software governed by the CeCILL license (see ./LICENSE) |
|---|
| 41 | !!---------------------------------------------------------------------- |
|---|
| 42 | CONTAINS |
|---|
| 43 | |
|---|
| 44 | SUBROUTINE sbc_ice_if( kt ) |
|---|
| 45 | !!--------------------------------------------------------------------- |
|---|
| 46 | !! *** ROUTINE sbc_ice_if *** |
|---|
| 47 | !! |
|---|
| 48 | !! ** Purpose : handle surface boundary condition over ice cover area |
|---|
| 49 | !! when sea-ice model are not used |
|---|
| 50 | !! |
|---|
| 51 | !! ** Method : - read sea-ice cover climatology |
|---|
| 52 | !! - blah blah blah, ... |
|---|
| 53 | !! |
|---|
| 54 | !! ** Action : utau, vtau : remain unchanged |
|---|
| 55 | !! taum, wndm : remain unchanged |
|---|
| 56 | !! qns, qsr : update heat flux below sea-ice |
|---|
| 57 | !! emp, sfx : update freshwater flux below sea-ice |
|---|
| 58 | !! fr_i : update the ice fraction |
|---|
| 59 | !!--------------------------------------------------------------------- |
|---|
| 60 | INTEGER, INTENT(in) :: kt ! ocean time step |
|---|
| 61 | ! |
|---|
| 62 | INTEGER :: ji, jj ! dummy loop indices |
|---|
| 63 | INTEGER :: ierror ! return error code |
|---|
| 64 | INTEGER :: ios ! Local integer output status for namelist read |
|---|
| 65 | REAL(wp) :: ztrp, zsice, zt_fzp, zfr_obs |
|---|
| 66 | REAL(wp) :: zqri, zqrj, zqrp, zqi |
|---|
| 67 | !! |
|---|
| 68 | CHARACTER(len=100) :: cn_dir ! Root directory for location of ice-if files |
|---|
| 69 | TYPE(FLD_N) :: sn_ice ! informations about the fields to be read |
|---|
| 70 | NAMELIST/namsbc_iif/ cn_dir, sn_ice |
|---|
| 71 | !!--------------------------------------------------------------------- |
|---|
| 72 | ! ! ====================== ! |
|---|
| 73 | IF( kt == nit000 ) THEN ! First call kt=nit000 ! |
|---|
| 74 | ! ! ====================== ! |
|---|
| 75 | ! set file information |
|---|
| 76 | READ ( numnam_ref, namsbc_iif, IOSTAT = ios, ERR = 901) |
|---|
| 77 | 901 IF( ios /= 0 ) CALL ctl_nam ( ios , 'namsbc_iif in reference namelist' ) |
|---|
| 78 | |
|---|
| 79 | READ ( numnam_cfg, namsbc_iif, IOSTAT = ios, ERR = 902 ) |
|---|
| 80 | 902 IF( ios > 0 ) CALL ctl_nam ( ios , 'namsbc_iif in configuration namelist' ) |
|---|
| 81 | IF(lwm) WRITE ( numond, namsbc_iif ) |
|---|
| 82 | |
|---|
| 83 | ALLOCATE( sf_ice(1), STAT=ierror ) |
|---|
| 84 | IF( ierror > 0 ) CALL ctl_stop( 'STOP', 'sbc_ice_if: unable to allocate sf_ice structure' ) |
|---|
| 85 | ALLOCATE( sf_ice(1)%fnow(jpi,jpj,1) ) |
|---|
| 86 | IF( sn_ice%ln_tint ) ALLOCATE( sf_ice(1)%fdta(jpi,jpj,1,2) ) |
|---|
| 87 | |
|---|
| 88 | ! fill sf_ice with sn_ice and control print |
|---|
| 89 | CALL fld_fill( sf_ice, (/ sn_ice /), cn_dir, 'sbc_ice_if', 'ice-if sea-ice model', 'namsbc_iif' ) |
|---|
| 90 | ! |
|---|
| 91 | ENDIF |
|---|
| 92 | |
|---|
| 93 | CALL fld_read( kt, nn_fsbc, sf_ice ) ! Read input fields and provides the |
|---|
| 94 | ! ! input fields at the current time-step |
|---|
| 95 | |
|---|
| 96 | IF( MOD( kt-1, nn_fsbc) == 0 ) THEN |
|---|
| 97 | ! |
|---|
| 98 | ztrp = -40. ! restoring terme for temperature (w/m2/k) |
|---|
| 99 | zsice = - 0.04 / 0.8 ! ratio of isohaline compressibility over isotherme compressibility |
|---|
| 100 | ! ( d rho / dt ) / ( d rho / ds ) ( s = 34, t = -1.8 ) |
|---|
| 101 | |
|---|
| 102 | CALL eos_fzp( sss_m(:,:), fr_i(:,:) ) ! sea surface freezing temperature [Celsius] |
|---|
| 103 | fr_i(:,:) = fr_i(:,:) * tmask(:,:,1) |
|---|
| 104 | |
|---|
| 105 | IF( ln_cpl ) a_i(:,:,1) = fr_i(:,:) |
|---|
| 106 | |
|---|
| 107 | ! Flux and ice fraction computation |
|---|
| 108 | DO jj = 1, jpj |
|---|
| 109 | DO ji = 1, jpi |
|---|
| 110 | ! |
|---|
| 111 | zt_fzp = fr_i(ji,jj) ! freezing point temperature |
|---|
| 112 | zfr_obs = sf_ice(1)%fnow(ji,jj,1) ! observed ice cover |
|---|
| 113 | ! ! ocean ice fraction (0/1) from the freezing point temperature |
|---|
| 114 | IF( sst_m(ji,jj) <= zt_fzp ) THEN ; fr_i(ji,jj) = 1.e0 |
|---|
| 115 | ELSE ; fr_i(ji,jj) = 0.e0 |
|---|
| 116 | ENDIF |
|---|
| 117 | |
|---|
| 118 | tsn(ji,jj,1,jp_tem) = MAX( tsn(ji,jj,1,jp_tem), zt_fzp ) ! avoid over-freezing point temperature |
|---|
| 119 | |
|---|
| 120 | qsr(ji,jj) = ( 1. - zfr_obs ) * qsr(ji,jj) ! solar heat flux : zero below observed ice cover |
|---|
| 121 | |
|---|
| 122 | ! ! non solar heat flux : add a damping term |
|---|
| 123 | ! # ztrp*(t-(tgel-1.)) if observed ice and no opa ice (zfr_obs=1 fr_i=0) |
|---|
| 124 | ! # ztrp*min(0,t-tgel) if observed ice and opa ice (zfr_obs=1 fr_i=1) |
|---|
| 125 | zqri = ztrp * ( tsb(ji,jj,1,jp_tem) - ( zt_fzp - 1.) ) |
|---|
| 126 | zqrj = ztrp * MIN( 0., tsb(ji,jj,1,jp_tem) - zt_fzp ) |
|---|
| 127 | zqrp = ( zfr_obs * ( (1. - fr_i(ji,jj) ) * zqri & |
|---|
| 128 | & + fr_i(ji,jj) * zqrj ) ) * tmask(ji,jj,1) |
|---|
| 129 | |
|---|
| 130 | ! ! non-solar heat flux |
|---|
| 131 | ! # qns unchanged if no climatological ice (zfr_obs=0) |
|---|
| 132 | ! # qns = zqrp if climatological ice and no opa ice (zfr_obs=1, fr_i=0) |
|---|
| 133 | ! # qns = zqrp -2(-4) watt/m2 if climatological ice and opa ice (zfr_obs=1, fr_i=1) |
|---|
| 134 | ! (-2=arctic, -4=antarctic) |
|---|
| 135 | zqi = -3. + SIGN( 1._wp, ff_f(ji,jj) ) |
|---|
| 136 | qns(ji,jj) = ( ( 1.- zfr_obs ) * qns(ji,jj) & |
|---|
| 137 | & + zfr_obs * fr_i(ji,jj) * zqi ) * tmask(ji,jj,1) & |
|---|
| 138 | & + zqrp |
|---|
| 139 | END DO |
|---|
| 140 | END DO |
|---|
| 141 | ! |
|---|
| 142 | ENDIF |
|---|
| 143 | ! |
|---|
| 144 | END SUBROUTINE sbc_ice_if |
|---|
| 145 | |
|---|
| 146 | !!====================================================================== |
|---|
| 147 | END MODULE sbcice_if |
|---|
