[8586] | 1 | MODULE icethd_dh |
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| 2 | !!====================================================================== |
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| 3 | !! *** MODULE icethd_dh *** |
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| 4 | !! seaice : thermodynamic growth and melt |
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| 5 | !!====================================================================== |
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[9604] | 6 | !! History : ! 2003-05 (M. Vancoppenolle) Original code in 1D |
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| 7 | !! ! 2005-06 (M. Vancoppenolle) 3D version |
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| 8 | !! 4.0 ! 2018 (many people) SI3 [aka Sea Ice cube] |
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[8586] | 9 | !!---------------------------------------------------------------------- |
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[9570] | 10 | #if defined key_si3 |
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[8586] | 11 | !!---------------------------------------------------------------------- |
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[9570] | 12 | !! 'key_si3' SI3 sea-ice model |
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[8586] | 13 | !!---------------------------------------------------------------------- |
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| 14 | !! ice_thd_dh : vertical sea-ice growth and melt |
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[13284] | 15 | !!---------------------------------------------------------------------- |
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[8586] | 16 | USE dom_oce ! ocean space and time domain |
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| 17 | USE phycst ! physical constants |
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| 18 | USE ice ! sea-ice: variables |
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| 19 | USE ice1D ! sea-ice: thermodynamics variables |
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| 20 | USE icethd_sal ! sea-ice: salinity profiles |
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[13284] | 21 | USE icevar ! for CALL ice_var_snwblow |
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[8586] | 22 | ! |
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| 23 | USE in_out_manager ! I/O manager |
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| 24 | USE lib_mpp ! MPP library |
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| 25 | USE lib_fortran ! fortran utilities (glob_sum + no signed zero) |
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| 26 | |
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| 27 | IMPLICIT NONE |
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| 28 | PRIVATE |
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| 29 | |
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| 30 | PUBLIC ice_thd_dh ! called by ice_thd |
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| 31 | |
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| 32 | !!---------------------------------------------------------------------- |
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[9598] | 33 | !! NEMO/ICE 4.0 , NEMO Consortium (2018) |
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[10069] | 34 | !! $Id$ |
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[10068] | 35 | !! Software governed by the CeCILL license (see ./LICENSE) |
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[8586] | 36 | !!---------------------------------------------------------------------- |
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| 37 | CONTAINS |
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| 38 | |
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| 39 | SUBROUTINE ice_thd_dh |
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| 40 | !!------------------------------------------------------------------ |
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| 41 | !! *** ROUTINE ice_thd_dh *** |
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| 42 | !! |
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[9274] | 43 | !! ** Purpose : compute ice and snow thickness changes due to growth/melting |
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[8586] | 44 | !! |
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| 45 | !! ** Method : Ice/Snow surface melting arises from imbalance in surface fluxes |
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[9274] | 46 | !! Bottom accretion/ablation arises from flux budget |
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| 47 | !! Snow thickness can increase by precipitation and decrease by sublimation |
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| 48 | !! If snow load excesses Archmiede limit, snow-ice is formed by |
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| 49 | !! the flooding of sea-water in the snow |
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[8586] | 50 | !! |
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[9274] | 51 | !! - Compute available flux of heat for surface ablation |
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| 52 | !! - Compute snow and sea ice enthalpies |
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| 53 | !! - Surface ablation and sublimation |
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| 54 | !! - Bottom accretion/ablation |
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| 55 | !! - Snow ice formation |
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[8586] | 56 | !! |
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| 57 | !! References : Bitz and Lipscomb, 1999, J. Geophys. Res. |
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| 58 | !! Fichefet T. and M. Maqueda 1997, J. Geophys. Res., 102(C6), 12609-12646 |
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| 59 | !! Vancoppenolle, Fichefet and Bitz, 2005, Geophys. Res. Let. |
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| 60 | !! Vancoppenolle et al.,2009, Ocean Modelling |
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| 61 | !!------------------------------------------------------------------ |
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| 62 | INTEGER :: ji, jk ! dummy loop indices |
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| 63 | INTEGER :: iter ! local integer |
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| 64 | |
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| 65 | REAL(wp) :: ztmelts ! local scalar |
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| 66 | REAL(wp) :: zdum |
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| 67 | REAL(wp) :: zfracs ! fractionation coefficient for bottom salt entrapment |
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| 68 | REAL(wp) :: zswi1 ! switch for computation of bottom salinity |
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| 69 | REAL(wp) :: zswi12 ! switch for computation of bottom salinity |
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| 70 | REAL(wp) :: zswi2 ! switch for computation of bottom salinity |
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| 71 | REAL(wp) :: zgrr ! bottom growth rate |
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| 72 | REAL(wp) :: zt_i_new ! bottom formation temperature |
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[9935] | 73 | REAL(wp) :: z1_rho ! 1/(rhos+rau0-rhoi) |
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[8586] | 74 | |
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| 75 | REAL(wp) :: zQm ! enthalpy exchanged with the ocean (J/m2), >0 towards the ocean |
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| 76 | REAL(wp) :: zEi ! specific enthalpy of sea ice (J/kg) |
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| 77 | REAL(wp) :: zEw ! specific enthalpy of exchanged water (J/kg) |
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| 78 | REAL(wp) :: zdE ! specific enthalpy difference (J/kg) |
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| 79 | REAL(wp) :: zfmdt ! exchange mass flux x time step (J/m2), >0 towards the ocean |
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| 80 | |
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| 81 | REAL(wp), DIMENSION(jpij) :: zqprec ! energy of fallen snow (J.m-3) |
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[9922] | 82 | REAL(wp), DIMENSION(jpij) :: zq_top ! heat for surface ablation (J.m-2) |
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| 83 | REAL(wp), DIMENSION(jpij) :: zq_bot ! heat for bottom ablation (J.m-2) |
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[8586] | 84 | REAL(wp), DIMENSION(jpij) :: zq_rema ! remaining heat at the end of the routine (J.m-2) |
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| 85 | REAL(wp), DIMENSION(jpij) :: zf_tt ! Heat budget to determine melting or freezing(W.m-2) |
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| 86 | REAL(wp), DIMENSION(jpij) :: zevap_rema ! remaining mass flux from sublimation (kg.m-2) |
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| 87 | |
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| 88 | REAL(wp), DIMENSION(jpij) :: zdh_s_mel ! snow melt |
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| 89 | REAL(wp), DIMENSION(jpij) :: zdh_s_pre ! snow precipitation |
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| 90 | REAL(wp), DIMENSION(jpij) :: zdh_s_sub ! snow sublimation |
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| 91 | |
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[9271] | 92 | REAL(wp), DIMENSION(jpij,nlay_s) :: zh_s ! snw layer thickness |
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| 93 | REAL(wp), DIMENSION(jpij,nlay_i) :: zh_i ! ice layer thickness |
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[8586] | 94 | REAL(wp), DIMENSION(jpij,nlay_i) :: zdeltah |
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| 95 | INTEGER , DIMENSION(jpij,nlay_i) :: icount ! number of layers vanished by melting |
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| 96 | |
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| 97 | REAL(wp), DIMENSION(jpij) :: zsnw ! distribution of snow after wind blowing |
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| 98 | |
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| 99 | REAL(wp) :: zswitch_sal |
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| 100 | |
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| 101 | INTEGER :: num_iter_max ! Heat conservation |
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| 102 | !!------------------------------------------------------------------ |
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| 103 | |
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| 104 | ! Discriminate between time varying salinity and constant |
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| 105 | SELECT CASE( nn_icesal ) ! varying salinity or not |
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| 106 | CASE( 1 , 3 ) ; zswitch_sal = 0._wp ! prescribed salinity profile |
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| 107 | CASE( 2 ) ; zswitch_sal = 1._wp ! varying salinity profile |
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| 108 | END SELECT |
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| 109 | |
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| 110 | ! initialize layer thicknesses and enthalpies |
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| 111 | h_i_old (1:npti,0:nlay_i+1) = 0._wp |
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| 112 | eh_i_old(1:npti,0:nlay_i+1) = 0._wp |
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| 113 | DO jk = 1, nlay_i |
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| 114 | DO ji = 1, npti |
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| 115 | h_i_old (ji,jk) = h_i_1d(ji) * r1_nlay_i |
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| 116 | eh_i_old(ji,jk) = e_i_1d(ji,jk) * h_i_old(ji,jk) |
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| 117 | END DO |
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| 118 | END DO |
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| 119 | ! |
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[9604] | 120 | ! ! ============================================== ! |
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| 121 | ! ! Available heat for surface and bottom ablation ! |
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| 122 | ! ! ============================================== ! |
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[8813] | 123 | ! |
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[10534] | 124 | IF( ln_cndflx .AND. .NOT.ln_cndemulate ) THEN |
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[8813] | 125 | ! |
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| 126 | DO ji = 1, npti |
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[9922] | 127 | zq_top(ji) = MAX( 0._wp, qml_ice_1d(ji) * rdt_ice ) |
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[8813] | 128 | END DO |
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| 129 | ! |
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[10534] | 130 | ELSE |
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[8813] | 131 | ! |
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| 132 | DO ji = 1, npti |
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[9916] | 133 | zdum = qns_ice_1d(ji) + qsr_ice_1d(ji) - qtr_ice_top_1d(ji) - qcn_ice_top_1d(ji) |
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[9274] | 134 | qml_ice_1d(ji) = zdum * MAX( 0._wp , SIGN( 1._wp, t_su_1d(ji) - rt0 ) ) |
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[9922] | 135 | zq_top(ji) = MAX( 0._wp, qml_ice_1d(ji) * rdt_ice ) |
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[8813] | 136 | END DO |
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| 137 | ! |
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[10534] | 138 | ENDIF |
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[8813] | 139 | ! |
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[8586] | 140 | DO ji = 1, npti |
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[13642] | 141 | zf_tt(ji) = qcn_ice_bot_1d(ji) + qsb_ice_bot_1d(ji) + fhld_1d(ji) + qtr_ice_bot_1d(ji) * frq_m_1d(ji) |
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[9922] | 142 | zq_bot(ji) = MAX( 0._wp, zf_tt(ji) * rdt_ice ) |
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[8586] | 143 | END DO |
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| 144 | |
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[9274] | 145 | ! Ice and snow layer thicknesses |
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| 146 | !------------------------------- |
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[9271] | 147 | DO jk = 1, nlay_i |
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| 148 | DO ji = 1, npti |
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| 149 | zh_i(ji,jk) = h_i_1d(ji) * r1_nlay_i |
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| 150 | END DO |
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| 151 | END DO |
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| 152 | |
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| 153 | DO jk = 1, nlay_s |
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| 154 | DO ji = 1, npti |
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| 155 | zh_s(ji,jk) = h_s_1d(ji) * r1_nlay_s |
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| 156 | END DO |
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| 157 | END DO |
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| 158 | |
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[9274] | 159 | ! ! ============ ! |
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| 160 | ! ! Snow ! |
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| 161 | ! ! ============ ! |
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| 162 | ! |
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| 163 | ! Internal melting |
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| 164 | ! ---------------- |
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| 165 | ! IF snow temperature is above freezing point, THEN snow melts (should not happen but sometimes it does) |
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[9271] | 166 | DO jk = 1, nlay_s |
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[8586] | 167 | DO ji = 1, npti |
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[9274] | 168 | IF( t_s_1d(ji,jk) > rt0 ) THEN |
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| 169 | hfx_res_1d (ji) = hfx_res_1d (ji) + e_s_1d(ji,jk) * zh_s(ji,jk) * a_i_1d(ji) * r1_rdtice ! heat flux to the ocean [W.m-2], < 0 |
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[9935] | 170 | wfx_snw_sum_1d(ji) = wfx_snw_sum_1d(ji) + rhos * zh_s(ji,jk) * a_i_1d(ji) * r1_rdtice ! mass flux |
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[9271] | 171 | ! updates |
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[9274] | 172 | dh_s_mlt(ji) = dh_s_mlt(ji) - zh_s(ji,jk) |
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| 173 | h_s_1d (ji) = h_s_1d(ji) - zh_s(ji,jk) |
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| 174 | zh_s (ji,jk) = 0._wp |
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| 175 | e_s_1d (ji,jk) = 0._wp |
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| 176 | t_s_1d (ji,jk) = rt0 |
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[9271] | 177 | END IF |
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[8586] | 178 | END DO |
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[9274] | 179 | END DO |
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[8586] | 180 | |
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[9274] | 181 | ! Snow precipitation |
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| 182 | !------------------- |
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[13284] | 183 | CALL ice_var_snwblow( 1. - at_i_1d(1:npti), zsnw(1:npti) ) ! snow distribution over ice after wind blowing |
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[8586] | 184 | |
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| 185 | zdeltah(1:npti,:) = 0._wp |
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| 186 | DO ji = 1, npti |
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[9274] | 187 | IF( sprecip_1d(ji) > 0._wp ) THEN |
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| 188 | ! |
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| 189 | ! --- precipitation --- |
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[9935] | 190 | zdh_s_pre (ji) = zsnw(ji) * sprecip_1d(ji) * rdt_ice * r1_rhos / at_i_1d(ji) ! thickness change |
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[9274] | 191 | zqprec (ji) = - qprec_ice_1d(ji) ! enthalpy of the precip (>0, J.m-3) |
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| 192 | ! |
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| 193 | hfx_spr_1d(ji) = hfx_spr_1d(ji) + zdh_s_pre(ji) * a_i_1d(ji) * zqprec(ji) * r1_rdtice ! heat flux from snow precip (>0, W.m-2) |
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[9935] | 194 | wfx_spr_1d(ji) = wfx_spr_1d(ji) - rhos * a_i_1d(ji) * zdh_s_pre(ji) * r1_rdtice ! mass flux, <0 |
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[9274] | 195 | |
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| 196 | ! --- melt of falling snow --- |
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| 197 | rswitch = MAX( 0._wp , SIGN( 1._wp , zqprec(ji) - epsi20 ) ) |
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[9922] | 198 | zdeltah (ji,1) = - rswitch * zq_top(ji) / MAX( zqprec(ji) , epsi20 ) ! thickness change |
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| 199 | zdeltah (ji,1) = MAX( - zdh_s_pre(ji), zdeltah(ji,1) ) ! bound melting |
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[9274] | 200 | hfx_snw_1d (ji) = hfx_snw_1d (ji) - zdeltah(ji,1) * a_i_1d(ji) * zqprec(ji) * r1_rdtice ! heat used to melt snow (W.m-2, >0) |
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[9935] | 201 | wfx_snw_sum_1d(ji) = wfx_snw_sum_1d(ji) - rhos * a_i_1d(ji) * zdeltah(ji,1) * r1_rdtice ! snow melting only = water into the ocean (then without snow precip), >0 |
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[9274] | 202 | |
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| 203 | ! updates available heat + precipitations after melting |
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| 204 | dh_s_mlt (ji) = dh_s_mlt(ji) + zdeltah(ji,1) |
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[9922] | 205 | zq_top (ji) = MAX( 0._wp , zq_top (ji) + zdeltah(ji,1) * zqprec(ji) ) |
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[9274] | 206 | zdh_s_pre(ji) = zdh_s_pre(ji) + zdeltah(ji,1) |
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| 207 | |
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| 208 | ! update thickness |
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| 209 | h_s_1d(ji) = MAX( 0._wp , h_s_1d(ji) + zdh_s_pre(ji) ) |
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| 210 | ! |
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| 211 | ELSE |
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| 212 | ! |
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| 213 | zdh_s_pre(ji) = 0._wp |
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| 214 | zqprec (ji) = 0._wp |
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| 215 | ! |
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| 216 | ENDIF |
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[8586] | 217 | END DO |
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| 218 | |
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[9271] | 219 | ! recalculate snow layers |
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| 220 | DO jk = 1, nlay_s |
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| 221 | DO ji = 1, npti |
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| 222 | zh_s(ji,jk) = h_s_1d(ji) * r1_nlay_s |
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| 223 | END DO |
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| 224 | END DO |
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| 225 | |
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[9274] | 226 | ! Snow melting |
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| 227 | ! ------------ |
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[9922] | 228 | ! If heat still available (zq_top > 0), then melt more snow |
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[8586] | 229 | zdeltah(1:npti,:) = 0._wp |
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| 230 | zdh_s_mel(1:npti) = 0._wp |
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| 231 | DO jk = 1, nlay_s |
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| 232 | DO ji = 1, npti |
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[9922] | 233 | IF( zh_s(ji,jk) > 0._wp .AND. zq_top(ji) > 0._wp ) THEN |
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[9274] | 234 | ! |
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| 235 | rswitch = MAX( 0._wp, SIGN( 1._wp, e_s_1d(ji,jk) - epsi20 ) ) |
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[9922] | 236 | zdeltah (ji,jk) = - rswitch * zq_top(ji) / MAX( e_s_1d(ji,jk), epsi20 ) ! thickness change |
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| 237 | zdeltah (ji,jk) = MAX( zdeltah(ji,jk) , - zh_s(ji,jk) ) ! bound melting |
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[9274] | 238 | zdh_s_mel(ji) = zdh_s_mel(ji) + zdeltah(ji,jk) |
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| 239 | |
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| 240 | hfx_snw_1d(ji) = hfx_snw_1d(ji) - zdeltah(ji,jk) * a_i_1d(ji) * e_s_1d (ji,jk) * r1_rdtice ! heat used to melt snow(W.m-2, >0) |
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[9935] | 241 | wfx_snw_sum_1d(ji) = wfx_snw_sum_1d(ji) - rhos * a_i_1d(ji) * zdeltah(ji,jk) * r1_rdtice ! snow melting only = water into the ocean (then without snow precip) |
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[9274] | 242 | |
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| 243 | ! updates available heat + thickness |
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| 244 | dh_s_mlt(ji) = dh_s_mlt(ji) + zdeltah(ji,jk) |
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[9922] | 245 | zq_top (ji) = MAX( 0._wp , zq_top(ji) + zdeltah(ji,jk) * e_s_1d(ji,jk) ) |
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[9274] | 246 | h_s_1d (ji) = MAX( 0._wp , h_s_1d(ji) + zdeltah(ji,jk) ) |
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| 247 | zh_s (ji,jk) = MAX( 0._wp , zh_s(ji,jk) + zdeltah(ji,jk) ) |
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| 248 | ! |
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| 249 | ENDIF |
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[8586] | 250 | END DO |
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| 251 | END DO |
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| 252 | |
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[9274] | 253 | ! Snow sublimation |
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| 254 | !----------------- |
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[8586] | 255 | ! qla_ice is always >=0 (upwards), heat goes to the atmosphere, therefore snow sublimates |
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[8885] | 256 | ! comment: not counted in mass/heat exchange in iceupdate.F90 since this is an exchange with atm. (not ocean) |
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[8586] | 257 | zdeltah(1:npti,:) = 0._wp |
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| 258 | DO ji = 1, npti |
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[9274] | 259 | IF( evap_ice_1d(ji) > 0._wp ) THEN |
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| 260 | ! |
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[9935] | 261 | zdh_s_sub (ji) = MAX( - h_s_1d(ji) , - evap_ice_1d(ji) * r1_rhos * rdt_ice ) |
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| 262 | zevap_rema(ji) = evap_ice_1d(ji) * rdt_ice + zdh_s_sub(ji) * rhos ! remaining evap in kg.m-2 (used for ice melting later on) |
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[9274] | 263 | zdeltah (ji,1) = MAX( zdh_s_sub(ji), - zdh_s_pre(ji) ) |
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| 264 | |
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| 265 | hfx_sub_1d (ji) = hfx_sub_1d(ji) + & ! Heat flux by sublimation [W.m-2], < 0 (sublimate snow that had fallen, then pre-existing snow) |
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| 266 | & ( zdeltah(ji,1) * zqprec(ji) + ( zdh_s_sub(ji) - zdeltah(ji,1) ) * e_s_1d(ji,1) ) & |
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| 267 | & * a_i_1d(ji) * r1_rdtice |
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[9935] | 268 | wfx_snw_sub_1d(ji) = wfx_snw_sub_1d(ji) - rhos * a_i_1d(ji) * zdh_s_sub(ji) * r1_rdtice ! Mass flux by sublimation |
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[9274] | 269 | |
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| 270 | ! new snow thickness |
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| 271 | h_s_1d(ji) = MAX( 0._wp , h_s_1d(ji) + zdh_s_sub(ji) ) |
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| 272 | ! update precipitations after sublimation and correct sublimation |
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| 273 | zdh_s_pre(ji) = zdh_s_pre(ji) + zdeltah(ji,1) |
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| 274 | zdh_s_sub(ji) = zdh_s_sub(ji) - zdeltah(ji,1) |
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| 275 | ! |
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| 276 | ELSE |
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| 277 | ! |
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| 278 | zdh_s_sub (ji) = 0._wp |
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| 279 | zevap_rema(ji) = 0._wp |
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| 280 | ! |
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| 281 | ENDIF |
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[8586] | 282 | END DO |
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| 283 | |
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| 284 | ! --- Update snow diags --- ! |
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| 285 | DO ji = 1, npti |
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| 286 | dh_s_tot(ji) = zdh_s_mel(ji) + zdh_s_pre(ji) + zdh_s_sub(ji) |
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| 287 | END DO |
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| 288 | |
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[9274] | 289 | ! Update temperature, energy |
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| 290 | !--------------------------- |
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[8586] | 291 | ! new temp and enthalpy of the snow (remaining snow precip + remaining pre-existing snow) |
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| 292 | DO jk = 1, nlay_s |
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| 293 | DO ji = 1,npti |
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| 294 | rswitch = MAX( 0._wp , SIGN( 1._wp, h_s_1d(ji) - epsi20 ) ) |
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[9274] | 295 | e_s_1d(ji,jk) = rswitch / MAX( h_s_1d(ji), epsi20 ) * & |
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| 296 | & ( ( zdh_s_pre(ji) ) * zqprec(ji) + & |
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[9935] | 297 | & ( h_s_1d(ji) - zdh_s_pre(ji) ) * rhos * ( rcpi * ( rt0 - t_s_1d(ji,jk) ) + rLfus ) ) |
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[8586] | 298 | END DO |
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| 299 | END DO |
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[9274] | 300 | |
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| 301 | ! ! ============ ! |
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| 302 | ! ! Ice ! |
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| 303 | ! ! ============ ! |
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[8586] | 304 | |
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[9274] | 305 | ! Surface ice melting |
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| 306 | !-------------------- |
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[8586] | 307 | zdeltah(1:npti,:) = 0._wp ! important |
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| 308 | DO jk = 1, nlay_i |
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| 309 | DO ji = 1, npti |
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[9935] | 310 | ztmelts = - rTmlt * sz_i_1d(ji,jk) ! Melting point of layer k [C] |
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[8586] | 311 | |
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[9274] | 312 | IF( t_i_1d(ji,jk) >= (ztmelts+rt0) ) THEN !-- Internal melting |
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[8586] | 313 | |
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[9935] | 314 | zEi = - e_i_1d(ji,jk) * r1_rhoi ! Specific enthalpy of layer k [J/kg, <0] |
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[9274] | 315 | zdE = 0._wp ! Specific enthalpy difference (J/kg, <0) |
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[8586] | 316 | ! set up at 0 since no energy is needed to melt water...(it is already melted) |
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| 317 | zdeltah(ji,jk) = MIN( 0._wp , - zh_i(ji,jk) ) ! internal melting occurs when the internal temperature is above freezing |
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| 318 | ! this should normally not happen, but sometimes, heat diffusion leads to this |
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[9935] | 319 | zfmdt = - zdeltah(ji,jk) * rhoi ! Mass flux x time step > 0 |
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[8586] | 320 | |
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[9750] | 321 | dh_i_itm(ji) = dh_i_itm(ji) + zdeltah(ji,jk) ! Cumulate internal melting |
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[8586] | 322 | |
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[9935] | 323 | zfmdt = - rhoi * zdeltah(ji,jk) ! Recompute mass flux [kg/m2, >0] |
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[8586] | 324 | |
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[9274] | 325 | hfx_res_1d(ji) = hfx_res_1d(ji) + zfmdt * a_i_1d(ji) * zEi * r1_rdtice ! Heat flux to the ocean [W.m-2], <0 |
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| 326 | ! ice enthalpy zEi is "sent" to the ocean |
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[9935] | 327 | sfx_res_1d(ji) = sfx_res_1d(ji) - rhoi * a_i_1d(ji) * zdeltah(ji,jk) * s_i_1d(ji) * r1_rdtice ! Salt flux |
---|
[9274] | 328 | ! using s_i_1d and not sz_i_1d(jk) is ok |
---|
[9935] | 329 | wfx_res_1d(ji) = wfx_res_1d(ji) - rhoi * a_i_1d(ji) * zdeltah(ji,jk) * r1_rdtice ! Mass flux |
---|
[8586] | 330 | |
---|
[9274] | 331 | ELSE !-- Surface melting |
---|
[8586] | 332 | |
---|
[9935] | 333 | zEi = - e_i_1d(ji,jk) * r1_rhoi ! Specific enthalpy of layer k [J/kg, <0] |
---|
[8586] | 334 | zEw = rcp * ztmelts ! Specific enthalpy of resulting meltwater [J/kg, <0] |
---|
| 335 | zdE = zEi - zEw ! Specific enthalpy difference < 0 |
---|
| 336 | |
---|
[9922] | 337 | zfmdt = - zq_top(ji) / zdE ! Mass flux to the ocean [kg/m2, >0] |
---|
[8586] | 338 | |
---|
[9935] | 339 | zdeltah(ji,jk) = - zfmdt * r1_rhoi ! Melt of layer jk [m, <0] |
---|
[8586] | 340 | |
---|
| 341 | zdeltah(ji,jk) = MIN( 0._wp , MAX( zdeltah(ji,jk) , - zh_i(ji,jk) ) ) ! Melt of layer jk cannot exceed the layer thickness [m, <0] |
---|
| 342 | |
---|
[9935] | 343 | zq_top(ji) = MAX( 0._wp , zq_top(ji) - zdeltah(ji,jk) * rhoi * zdE ) ! update available heat |
---|
[8586] | 344 | |
---|
[9750] | 345 | dh_i_sum(ji) = dh_i_sum(ji) + zdeltah(ji,jk) ! Cumulate surface melt |
---|
[8586] | 346 | |
---|
[9935] | 347 | zfmdt = - rhoi * zdeltah(ji,jk) ! Recompute mass flux [kg/m2, >0] |
---|
[8586] | 348 | |
---|
| 349 | zQm = zfmdt * zEw ! Energy of the melt water sent to the ocean [J/m2, <0] |
---|
| 350 | |
---|
[9935] | 351 | sfx_sum_1d(ji) = sfx_sum_1d(ji) - rhoi * a_i_1d(ji) * zdeltah(ji,jk) * s_i_1d(ji) * r1_rdtice ! Salt flux >0 |
---|
[9274] | 352 | ! using s_i_1d and not sz_i_1d(jk) is ok) |
---|
| 353 | hfx_thd_1d(ji) = hfx_thd_1d(ji) + zfmdt * a_i_1d(ji) * zEw * r1_rdtice ! Heat flux [W.m-2], < 0 |
---|
| 354 | hfx_sum_1d(ji) = hfx_sum_1d(ji) - zfmdt * a_i_1d(ji) * zdE * r1_rdtice ! Heat flux used in this process [W.m-2], > 0 |
---|
| 355 | ! |
---|
[9935] | 356 | wfx_sum_1d(ji) = wfx_sum_1d(ji) - rhoi * a_i_1d(ji) * zdeltah(ji,jk) * r1_rdtice ! Mass flux |
---|
[8586] | 357 | |
---|
| 358 | END IF |
---|
[9274] | 359 | |
---|
| 360 | ! Ice sublimation |
---|
| 361 | ! --------------- |
---|
[9935] | 362 | zdum = MAX( - ( zh_i(ji,jk) + zdeltah(ji,jk) ) , - zevap_rema(ji) * r1_rhoi ) |
---|
[9274] | 363 | zdeltah (ji,jk) = zdeltah (ji,jk) + zdum |
---|
| 364 | dh_i_sub(ji) = dh_i_sub(ji) + zdum |
---|
| 365 | |
---|
[9935] | 366 | sfx_sub_1d(ji) = sfx_sub_1d(ji) - rhoi * a_i_1d(ji) * zdum * s_i_1d(ji) * r1_rdtice ! Salt flux >0 |
---|
[9274] | 367 | ! clem: flux is sent to the ocean for simplicity |
---|
| 368 | ! but salt should remain in the ice except |
---|
| 369 | ! if all ice is melted. => must be corrected |
---|
| 370 | hfx_sub_1d(ji) = hfx_sub_1d(ji) + zdum * e_i_1d(ji,jk) * a_i_1d(ji) * r1_rdtice ! Heat flux [W.m-2], < 0 |
---|
[8586] | 371 | |
---|
[9935] | 372 | wfx_ice_sub_1d(ji) = wfx_ice_sub_1d(ji) - rhoi * a_i_1d(ji) * zdum * r1_rdtice ! Mass flux > 0 |
---|
[9274] | 373 | |
---|
[8586] | 374 | ! update remaining mass flux |
---|
[9935] | 375 | zevap_rema(ji) = zevap_rema(ji) + zdum * rhoi |
---|
[8586] | 376 | |
---|
| 377 | ! record which layers have disappeared (for bottom melting) |
---|
| 378 | ! => icount=0 : no layer has vanished |
---|
| 379 | ! => icount=5 : 5 layers have vanished |
---|
| 380 | rswitch = MAX( 0._wp , SIGN( 1._wp , - ( zh_i(ji,jk) + zdeltah(ji,jk) ) ) ) |
---|
| 381 | icount(ji,jk) = NINT( rswitch ) |
---|
| 382 | zh_i(ji,jk) = MAX( 0._wp , zh_i(ji,jk) + zdeltah(ji,jk) ) |
---|
| 383 | |
---|
| 384 | ! update heat content (J.m-2) and layer thickness |
---|
| 385 | eh_i_old(ji,jk) = eh_i_old(ji,jk) + zdeltah(ji,jk) * e_i_1d(ji,jk) |
---|
| 386 | h_i_old (ji,jk) = h_i_old (ji,jk) + zdeltah(ji,jk) |
---|
| 387 | END DO |
---|
| 388 | END DO |
---|
[9274] | 389 | |
---|
[8586] | 390 | ! update ice thickness |
---|
| 391 | DO ji = 1, npti |
---|
[9750] | 392 | h_i_1d(ji) = MAX( 0._wp , h_i_1d(ji) + dh_i_sum(ji) + dh_i_itm(ji) + dh_i_sub(ji) ) |
---|
[8586] | 393 | END DO |
---|
| 394 | |
---|
| 395 | ! remaining "potential" evap is sent to ocean |
---|
| 396 | DO ji = 1, npti |
---|
| 397 | wfx_err_sub_1d(ji) = wfx_err_sub_1d(ji) - zevap_rema(ji) * a_i_1d(ji) * r1_rdtice ! <=0 (net evap for the ocean in kg.m-2.s-1) |
---|
| 398 | END DO |
---|
| 399 | |
---|
| 400 | |
---|
[9274] | 401 | ! Ice Basal growth |
---|
[8586] | 402 | !------------------ |
---|
| 403 | ! Basal growth is driven by heat imbalance at the ice-ocean interface, |
---|
[9916] | 404 | ! between the inner conductive flux (qcn_ice_bot), from the open water heat flux |
---|
[9913] | 405 | ! (fhld) and the sensible ice-ocean flux (qsb_ice_bot). |
---|
[9916] | 406 | ! qcn_ice_bot is positive downwards. qsb_ice_bot and fhld are positive to the ice |
---|
[8586] | 407 | |
---|
| 408 | ! If salinity varies in time, an iterative procedure is required, because |
---|
| 409 | ! the involved quantities are inter-dependent. |
---|
[9750] | 410 | ! Basal growth (dh_i_bog) depends upon new ice specific enthalpy (zEi), |
---|
| 411 | ! which depends on forming ice salinity (s_i_new), which depends on dh/dt (dh_i_bog) |
---|
[8586] | 412 | ! -> need for an iterative procedure, which converges quickly |
---|
| 413 | |
---|
| 414 | num_iter_max = 1 |
---|
| 415 | IF( nn_icesal == 2 ) num_iter_max = 5 ! salinity varying in time |
---|
| 416 | |
---|
| 417 | DO ji = 1, npti |
---|
| 418 | IF( zf_tt(ji) < 0._wp ) THEN |
---|
[9274] | 419 | DO iter = 1, num_iter_max ! iterations |
---|
[8586] | 420 | |
---|
| 421 | ! New bottom ice salinity (Cox & Weeks, JGR88 ) |
---|
| 422 | !--- zswi1 if dh/dt < 2.0e-8 |
---|
| 423 | !--- zswi12 if 2.0e-8 < dh/dt < 3.6e-7 |
---|
| 424 | !--- zswi2 if dh/dt > 3.6e-7 |
---|
[9750] | 425 | zgrr = MIN( 1.0e-3, MAX ( dh_i_bog(ji) * r1_rdtice , epsi10 ) ) |
---|
[9274] | 426 | zswi2 = MAX( 0._wp , SIGN( 1._wp , zgrr - 3.6e-7 ) ) |
---|
| 427 | zswi12 = MAX( 0._wp , SIGN( 1._wp , zgrr - 2.0e-8 ) ) * ( 1.0 - zswi2 ) |
---|
| 428 | zswi1 = 1. - zswi2 * zswi12 |
---|
| 429 | zfracs = MIN( zswi1 * 0.12 + zswi12 * ( 0.8925 + 0.0568 * LOG( 100.0 * zgrr ) ) & |
---|
| 430 | & + zswi2 * 0.26 / ( 0.26 + 0.74 * EXP ( - 724300.0 * zgrr ) ) , 0.5 ) |
---|
[8586] | 431 | |
---|
[9274] | 432 | s_i_new(ji) = zswitch_sal * zfracs * sss_1d(ji) + ( 1. - zswitch_sal ) * s_i_1d(ji) ! New ice salinity |
---|
[8586] | 433 | |
---|
[9935] | 434 | ztmelts = - rTmlt * s_i_new(ji) ! New ice melting point (C) |
---|
[9274] | 435 | |
---|
| 436 | zt_i_new = zswitch_sal * t_bo_1d(ji) + ( 1. - zswitch_sal) * t_i_1d(ji, nlay_i) |
---|
[8586] | 437 | |
---|
[9935] | 438 | zEi = rcpi * ( zt_i_new - (ztmelts+rt0) ) & ! Specific enthalpy of forming ice (J/kg, <0) |
---|
| 439 | & - rLfus * ( 1.0 - ztmelts / ( zt_i_new - rt0 ) ) + rcp * ztmelts |
---|
[8586] | 440 | |
---|
[9274] | 441 | zEw = rcp * ( t_bo_1d(ji) - rt0 ) ! Specific enthalpy of seawater (J/kg, < 0) |
---|
[8586] | 442 | |
---|
[9274] | 443 | zdE = zEi - zEw ! Specific enthalpy difference (J/kg, <0) |
---|
[8586] | 444 | |
---|
[9935] | 445 | dh_i_bog(ji) = rdt_ice * MAX( 0._wp , zf_tt(ji) / ( zdE * rhoi ) ) |
---|
[8586] | 446 | |
---|
| 447 | END DO |
---|
| 448 | ! Contribution to Energy and Salt Fluxes |
---|
[9935] | 449 | zfmdt = - rhoi * dh_i_bog(ji) ! Mass flux x time step (kg/m2, < 0) |
---|
[8586] | 450 | |
---|
[9274] | 451 | hfx_thd_1d(ji) = hfx_thd_1d(ji) + zfmdt * a_i_1d(ji) * zEw * r1_rdtice ! Heat flux to the ocean [W.m-2], >0 |
---|
| 452 | hfx_bog_1d(ji) = hfx_bog_1d(ji) - zfmdt * a_i_1d(ji) * zdE * r1_rdtice ! Heat flux used in this process [W.m-2], <0 |
---|
[8586] | 453 | |
---|
[9935] | 454 | sfx_bog_1d(ji) = sfx_bog_1d(ji) - rhoi * a_i_1d(ji) * dh_i_bog(ji) * s_i_new(ji) * r1_rdtice ! Salt flux, <0 |
---|
[8586] | 455 | |
---|
[9935] | 456 | wfx_bog_1d(ji) = wfx_bog_1d(ji) - rhoi * a_i_1d(ji) * dh_i_bog(ji) * r1_rdtice ! Mass flux, <0 |
---|
[8586] | 457 | |
---|
| 458 | ! update heat content (J.m-2) and layer thickness |
---|
[9935] | 459 | eh_i_old(ji,nlay_i+1) = eh_i_old(ji,nlay_i+1) + dh_i_bog(ji) * (-zEi * rhoi) |
---|
[9750] | 460 | h_i_old (ji,nlay_i+1) = h_i_old (ji,nlay_i+1) + dh_i_bog(ji) |
---|
[8586] | 461 | |
---|
| 462 | ENDIF |
---|
| 463 | |
---|
| 464 | END DO |
---|
| 465 | |
---|
[9274] | 466 | ! Ice Basal melt |
---|
| 467 | !--------------- |
---|
[8586] | 468 | zdeltah(1:npti,:) = 0._wp ! important |
---|
| 469 | DO jk = nlay_i, 1, -1 |
---|
| 470 | DO ji = 1, npti |
---|
| 471 | IF( zf_tt(ji) > 0._wp .AND. jk > icount(ji,jk) ) THEN ! do not calculate where layer has already disappeared by surface melting |
---|
| 472 | |
---|
[9935] | 473 | ztmelts = - rTmlt * sz_i_1d(ji,jk) ! Melting point of layer jk (C) |
---|
[8586] | 474 | |
---|
[9274] | 475 | IF( t_i_1d(ji,jk) >= (ztmelts+rt0) ) THEN !-- Internal melting |
---|
[8586] | 476 | |
---|
[9935] | 477 | zEi = - e_i_1d(ji,jk) * r1_rhoi ! Specific enthalpy of melting ice (J/kg, <0) |
---|
[8586] | 478 | zdE = 0._wp ! Specific enthalpy difference (J/kg, <0) |
---|
[9274] | 479 | ! set up at 0 since no energy is needed to melt water...(it is already melted) |
---|
[8586] | 480 | zdeltah (ji,jk) = MIN( 0._wp , - zh_i(ji,jk) ) ! internal melting occurs when the internal temperature is above freezing |
---|
| 481 | ! this should normally not happen, but sometimes, heat diffusion leads to this |
---|
| 482 | |
---|
[9750] | 483 | dh_i_itm (ji) = dh_i_itm(ji) + zdeltah(ji,jk) |
---|
[8586] | 484 | |
---|
[9935] | 485 | zfmdt = - zdeltah(ji,jk) * rhoi ! Mass flux x time step > 0 |
---|
[8586] | 486 | |
---|
[9274] | 487 | hfx_res_1d(ji) = hfx_res_1d(ji) + zfmdt * a_i_1d(ji) * zEi * r1_rdtice ! Heat flux to the ocean [W.m-2], <0 |
---|
| 488 | ! ice enthalpy zEi is "sent" to the ocean |
---|
[9935] | 489 | sfx_res_1d(ji) = sfx_res_1d(ji) - rhoi * a_i_1d(ji) * zdeltah(ji,jk) * s_i_1d(ji) * r1_rdtice ! Salt flux |
---|
[9274] | 490 | ! using s_i_1d and not sz_i_1d(jk) is ok |
---|
[9935] | 491 | wfx_res_1d(ji) = wfx_res_1d(ji) - rhoi * a_i_1d(ji) * zdeltah(ji,jk) * r1_rdtice ! Mass flux |
---|
[8586] | 492 | |
---|
| 493 | ! update heat content (J.m-2) and layer thickness |
---|
| 494 | eh_i_old(ji,jk) = eh_i_old(ji,jk) + zdeltah(ji,jk) * e_i_1d(ji,jk) |
---|
| 495 | h_i_old (ji,jk) = h_i_old (ji,jk) + zdeltah(ji,jk) |
---|
| 496 | |
---|
[9274] | 497 | ELSE !-- Basal melting |
---|
[8586] | 498 | |
---|
[9935] | 499 | zEi = - e_i_1d(ji,jk) * r1_rhoi ! Specific enthalpy of melting ice (J/kg, <0) |
---|
[9274] | 500 | zEw = rcp * ztmelts ! Specific enthalpy of meltwater (J/kg, <0) |
---|
| 501 | zdE = zEi - zEw ! Specific enthalpy difference (J/kg, <0) |
---|
[8586] | 502 | |
---|
[9922] | 503 | zfmdt = - zq_bot(ji) / zdE ! Mass flux x time step (kg/m2, >0) |
---|
[8586] | 504 | |
---|
[9935] | 505 | zdeltah(ji,jk) = - zfmdt * r1_rhoi ! Gross thickness change |
---|
[8586] | 506 | |
---|
[9274] | 507 | zdeltah(ji,jk) = MIN( 0._wp , MAX( zdeltah(ji,jk), - zh_i(ji,jk) ) ) ! bound thickness change |
---|
[8586] | 508 | |
---|
[9935] | 509 | zq_bot(ji) = MAX( 0._wp , zq_bot(ji) - zdeltah(ji,jk) * rhoi * zdE ) ! update available heat. MAX is necessary for roundup errors |
---|
[8586] | 510 | |
---|
[9922] | 511 | dh_i_bom(ji) = dh_i_bom(ji) + zdeltah(ji,jk) ! Update basal melt |
---|
[8586] | 512 | |
---|
[9935] | 513 | zfmdt = - zdeltah(ji,jk) * rhoi ! Mass flux x time step > 0 |
---|
[8586] | 514 | |
---|
[9274] | 515 | zQm = zfmdt * zEw ! Heat exchanged with ocean |
---|
[8586] | 516 | |
---|
[9274] | 517 | hfx_thd_1d(ji) = hfx_thd_1d(ji) + zfmdt * a_i_1d(ji) * zEw * r1_rdtice ! Heat flux to the ocean [W.m-2], <0 |
---|
| 518 | hfx_bom_1d(ji) = hfx_bom_1d(ji) - zfmdt * a_i_1d(ji) * zdE * r1_rdtice ! Heat used in this process [W.m-2], >0 |
---|
[8586] | 519 | |
---|
[9935] | 520 | sfx_bom_1d(ji) = sfx_bom_1d(ji) - rhoi * a_i_1d(ji) * zdeltah(ji,jk) * s_i_1d(ji) * r1_rdtice ! Salt flux |
---|
[9274] | 521 | ! using s_i_1d and not sz_i_1d(jk) is ok |
---|
[8586] | 522 | |
---|
[9935] | 523 | wfx_bom_1d(ji) = wfx_bom_1d(ji) - rhoi * a_i_1d(ji) * zdeltah(ji,jk) * r1_rdtice ! Mass flux |
---|
[8586] | 524 | |
---|
| 525 | ! update heat content (J.m-2) and layer thickness |
---|
| 526 | eh_i_old(ji,jk) = eh_i_old(ji,jk) + zdeltah(ji,jk) * e_i_1d(ji,jk) |
---|
| 527 | h_i_old (ji,jk) = h_i_old (ji,jk) + zdeltah(ji,jk) |
---|
| 528 | ENDIF |
---|
| 529 | |
---|
| 530 | ENDIF |
---|
| 531 | END DO |
---|
| 532 | END DO |
---|
| 533 | |
---|
| 534 | ! Update temperature, energy |
---|
[9274] | 535 | ! -------------------------- |
---|
[8586] | 536 | DO ji = 1, npti |
---|
[9750] | 537 | h_i_1d(ji) = MAX( 0._wp , h_i_1d(ji) + dh_i_bog(ji) + dh_i_bom(ji) ) |
---|
[8586] | 538 | END DO |
---|
| 539 | |
---|
[9274] | 540 | ! If heat still available then melt more snow |
---|
[8586] | 541 | !------------------------------------------- |
---|
| 542 | zdeltah(1:npti,:) = 0._wp ! important |
---|
| 543 | DO ji = 1, npti |
---|
[9922] | 544 | zq_rema (ji) = zq_top(ji) + zq_bot(ji) |
---|
[9274] | 545 | rswitch = 1._wp - MAX( 0._wp, SIGN( 1._wp, - h_s_1d(ji) ) ) ! =1 if snow |
---|
| 546 | rswitch = rswitch * MAX( 0._wp, SIGN( 1._wp, e_s_1d(ji,1) - epsi20 ) ) |
---|
| 547 | zdeltah (ji,1) = - rswitch * zq_rema(ji) / MAX( e_s_1d(ji,1), epsi20 ) |
---|
| 548 | zdeltah (ji,1) = MIN( 0._wp , MAX( zdeltah(ji,1) , - h_s_1d(ji) ) ) ! bound melting |
---|
| 549 | dh_s_tot(ji) = dh_s_tot(ji) + zdeltah(ji,1) |
---|
| 550 | h_s_1d (ji) = h_s_1d (ji) + zdeltah(ji,1) |
---|
[8586] | 551 | |
---|
[9274] | 552 | zq_rema(ji) = zq_rema(ji) + zdeltah(ji,1) * e_s_1d(ji,1) ! update available heat (J.m-2) |
---|
| 553 | hfx_snw_1d(ji) = hfx_snw_1d(ji) - zdeltah(ji,1) * a_i_1d(ji) * e_s_1d(ji,1) * r1_rdtice ! Heat used to melt snow, W.m-2 (>0) |
---|
[9935] | 554 | wfx_snw_sum_1d(ji) = wfx_snw_sum_1d(ji) - rhos * a_i_1d(ji) * zdeltah(ji,1) * r1_rdtice ! Mass flux |
---|
[8637] | 555 | dh_s_mlt(ji) = dh_s_mlt(ji) + zdeltah(ji,1) |
---|
[8586] | 556 | ! |
---|
| 557 | ! Remaining heat flux (W.m-2) is sent to the ocean heat budget |
---|
[13589] | 558 | !!!hfx_res_1d(ji) = hfx_res_1d(ji) + ( zq_rema(ji) * a_i_1d(ji) ) * r1_rdtice |
---|
[8586] | 559 | |
---|
| 560 | IF( ln_icectl .AND. zq_rema(ji) < 0. .AND. lwp ) WRITE(numout,*) 'ALERTE zq_rema <0 = ', zq_rema(ji) |
---|
| 561 | END DO |
---|
| 562 | |
---|
| 563 | ! |
---|
[9274] | 564 | ! Snow-Ice formation |
---|
| 565 | ! ------------------ |
---|
[8586] | 566 | ! When snow load excesses Archimede's limit, snow-ice interface goes down under sea-level, |
---|
| 567 | ! flooding of seawater transforms snow into ice dh_snowice is positive for the ice |
---|
[9935] | 568 | z1_rho = 1._wp / ( rhos+rau0-rhoi ) |
---|
[8586] | 569 | DO ji = 1, npti |
---|
| 570 | ! |
---|
[9935] | 571 | dh_snowice(ji) = MAX( 0._wp , ( rhos * h_s_1d(ji) + (rhoi-rau0) * h_i_1d(ji) ) * z1_rho ) |
---|
[8586] | 572 | |
---|
| 573 | h_i_1d(ji) = h_i_1d(ji) + dh_snowice(ji) |
---|
| 574 | h_s_1d(ji) = h_s_1d(ji) - dh_snowice(ji) |
---|
| 575 | |
---|
| 576 | ! Contribution to energy flux to the ocean [J/m2], >0 (if sst<0) |
---|
[9935] | 577 | zfmdt = ( rhos - rhoi ) * dh_snowice(ji) ! <0 |
---|
[8586] | 578 | zEw = rcp * sst_1d(ji) |
---|
| 579 | zQm = zfmdt * zEw |
---|
| 580 | |
---|
[9274] | 581 | hfx_thd_1d(ji) = hfx_thd_1d(ji) + zfmdt * a_i_1d(ji) * zEw * r1_rdtice ! Heat flux |
---|
[8586] | 582 | |
---|
[9274] | 583 | sfx_sni_1d(ji) = sfx_sni_1d(ji) + sss_1d(ji) * a_i_1d(ji) * zfmdt * r1_rdtice ! Salt flux |
---|
[8586] | 584 | |
---|
| 585 | ! Case constant salinity in time: virtual salt flux to keep salinity constant |
---|
[8637] | 586 | IF( nn_icesal /= 2 ) THEN |
---|
[8586] | 587 | sfx_bri_1d(ji) = sfx_bri_1d(ji) - sss_1d (ji) * a_i_1d(ji) * zfmdt * r1_rdtice & ! put back sss_m into the ocean |
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[9935] | 588 | & - s_i_1d(ji) * a_i_1d(ji) * dh_snowice(ji) * rhoi * r1_rdtice ! and get rn_icesal from the ocean |
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[8586] | 589 | ENDIF |
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| 590 | |
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[9274] | 591 | ! Mass flux: All snow is thrown in the ocean, and seawater is taken to replace the volume |
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[9935] | 592 | wfx_sni_1d(ji) = wfx_sni_1d(ji) - a_i_1d(ji) * dh_snowice(ji) * rhoi * r1_rdtice |
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| 593 | wfx_snw_sni_1d(ji) = wfx_snw_sni_1d(ji) + a_i_1d(ji) * dh_snowice(ji) * rhos * r1_rdtice |
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[8586] | 594 | |
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| 595 | ! update heat content (J.m-2) and layer thickness |
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| 596 | eh_i_old(ji,0) = eh_i_old(ji,0) + dh_snowice(ji) * e_s_1d(ji,1) + zfmdt * zEw |
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| 597 | h_i_old (ji,0) = h_i_old (ji,0) + dh_snowice(ji) |
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| 598 | |
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| 599 | END DO |
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| 600 | |
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| 601 | ! |
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| 602 | ! Update temperature, energy |
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[9274] | 603 | ! -------------------------- |
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[8586] | 604 | DO ji = 1, npti |
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[9274] | 605 | rswitch = 1._wp - MAX( 0._wp , SIGN( 1._wp , - h_i_1d(ji) ) ) |
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| 606 | t_su_1d(ji) = rswitch * t_su_1d(ji) + ( 1._wp - rswitch ) * rt0 |
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[8586] | 607 | END DO |
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| 608 | |
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| 609 | DO jk = 1, nlay_s |
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| 610 | DO ji = 1,npti |
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[10786] | 611 | ! where there is no ice or no snow |
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| 612 | rswitch = ( 1._wp - MAX( 0._wp, SIGN( 1._wp, - h_s_1d(ji) ) ) ) * ( 1._wp - MAX( 0._wp, SIGN(1._wp, - h_i_1d(ji) ) ) ) |
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| 613 | ! mass & energy loss to the ocean |
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| 614 | hfx_res_1d(ji) = hfx_res_1d(ji) + ( 1._wp - rswitch ) * & |
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| 615 | & ( e_s_1d(ji,jk) * h_s_1d(ji) * r1_nlay_s * a_i_1d(ji) * r1_rdtice ) ! heat flux to the ocean [W.m-2], < 0 |
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| 616 | wfx_res_1d(ji) = wfx_res_1d(ji) + ( 1._wp - rswitch ) * & |
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| 617 | & ( rhos * h_s_1d(ji) * r1_nlay_s * a_i_1d(ji) * r1_rdtice ) ! mass flux |
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| 618 | ! update energy (mass is updated in the next loop) |
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[8586] | 619 | e_s_1d(ji,jk) = rswitch * e_s_1d(ji,jk) |
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| 620 | ! recalculate t_s_1d from e_s_1d |
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[9935] | 621 | t_s_1d(ji,jk) = rt0 + rswitch * ( - e_s_1d(ji,jk) * r1_rhos * r1_rcpi + rLfus * r1_rcpi ) |
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[8586] | 622 | END DO |
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| 623 | END DO |
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| 624 | |
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[10786] | 625 | ! --- ensure that a_i = 0 & h_s = 0 where h_i = 0 --- |
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| 626 | WHERE( h_i_1d(1:npti) == 0._wp ) |
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| 627 | a_i_1d(1:npti) = 0._wp |
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| 628 | h_s_1d(1:npti) = 0._wp |
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| 629 | END WHERE |
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[8586] | 630 | ! |
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| 631 | END SUBROUTINE ice_thd_dh |
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| 632 | |
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| 633 | #else |
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| 634 | !!---------------------------------------------------------------------- |
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[9570] | 635 | !! Default option NO SI3 sea-ice model |
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[8586] | 636 | !!---------------------------------------------------------------------- |
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| 637 | #endif |
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| 638 | |
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| 639 | !!====================================================================== |
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| 640 | END MODULE icethd_dh |
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