[825] | 1 | MODULE limthd_dh |
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[1572] | 2 | !!====================================================================== |
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| 3 | !! *** MODULE limthd_dh *** |
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| 4 | !! LIM-3 : thermodynamic growth and decay of the ice |
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| 5 | !!====================================================================== |
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| 6 | !! History : LIM ! 2003-05 (M. Vancoppenolle) Original code in 1D |
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| 7 | !! ! 2005-06 (M. Vancoppenolle) 3D version |
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[4688] | 8 | !! 3.2 ! 2009-07 (M. Vancoppenolle, Y. Aksenov, G. Madec) bug correction in wfx_snw & wfx_ice |
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[3625] | 9 | !! 3.4 ! 2011-02 (G. Madec) dynamical allocation |
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| 10 | !! 3.5 ! 2012-10 (G. Madec & co) salt flux + bug fixes |
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[1572] | 11 | !!---------------------------------------------------------------------- |
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[825] | 12 | #if defined key_lim3 |
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[834] | 13 | !!---------------------------------------------------------------------- |
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| 14 | !! 'key_lim3' LIM3 sea-ice model |
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| 15 | !!---------------------------------------------------------------------- |
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[3625] | 16 | !! lim_thd_dh : vertical accr./abl. and lateral ablation of sea ice |
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[825] | 17 | !!---------------------------------------------------------------------- |
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[3625] | 18 | USE par_oce ! ocean parameters |
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| 19 | USE phycst ! physical constants (OCE directory) |
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| 20 | USE ice ! LIM variables |
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| 21 | USE thd_ice ! LIM thermodynamics |
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[8370] | 22 | ! |
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[3625] | 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 (allows no signed zero when 'key_nosignedzero' defined) |
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[4688] | 26 | |
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[825] | 27 | IMPLICIT NONE |
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| 28 | PRIVATE |
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| 29 | |
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[5407] | 30 | PUBLIC lim_thd_dh ! called by lim_thd |
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[5487] | 31 | PUBLIC lim_thd_snwblow ! called in sbcblk/sbcclio/sbccpl and here |
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[825] | 32 | |
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[5407] | 33 | INTERFACE lim_thd_snwblow |
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| 34 | MODULE PROCEDURE lim_thd_snwblow_1d, lim_thd_snwblow_2d |
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| 35 | END INTERFACE |
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| 36 | |
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[825] | 37 | !!---------------------------------------------------------------------- |
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[4161] | 38 | !! NEMO/LIM3 4.0 , UCL - NEMO Consortium (2010) |
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[1156] | 39 | !! $Id$ |
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[2715] | 40 | !! Software governed by the CeCILL licence (NEMOGCM/NEMO_CeCILL.txt) |
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[825] | 41 | !!---------------------------------------------------------------------- |
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| 42 | CONTAINS |
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| 43 | |
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[8342] | 44 | SUBROUTINE lim_thd_dh |
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[921] | 45 | !!------------------------------------------------------------------ |
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| 46 | !! *** ROUTINE lim_thd_dh *** |
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| 47 | !! |
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[1572] | 48 | !! ** Purpose : determines variations of ice and snow thicknesses. |
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[921] | 49 | !! |
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[1572] | 50 | !! ** Method : Ice/Snow surface melting arises from imbalance in surface fluxes |
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| 51 | !! Bottom accretion/ablation arises from flux budget |
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| 52 | !! Snow thickness can increase by precipitation and decrease by sublimation |
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| 53 | !! If snow load excesses Archmiede limit, snow-ice is formed by |
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| 54 | !! the flooding of sea-water in the snow |
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[921] | 55 | !! |
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[1572] | 56 | !! 1) Compute available flux of heat for surface ablation |
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| 57 | !! 2) Compute snow and sea ice enthalpies |
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| 58 | !! 3) Surface ablation and sublimation |
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| 59 | !! 4) Bottom accretion/ablation |
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| 60 | !! 5) Case of Total ablation |
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| 61 | !! 6) Snow ice formation |
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[921] | 62 | !! |
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[1572] | 63 | !! References : Bitz and Lipscomb, 1999, J. Geophys. Res. |
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| 64 | !! Fichefet T. and M. Maqueda 1997, J. Geophys. Res., 102(C6), 12609-12646 |
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| 65 | !! Vancoppenolle, Fichefet and Bitz, 2005, Geophys. Res. Let. |
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| 66 | !! Vancoppenolle et al.,2009, Ocean Modelling |
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[921] | 67 | !!------------------------------------------------------------------ |
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[1572] | 68 | INTEGER :: ji , jk ! dummy loop indices |
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| 69 | INTEGER :: iter |
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[825] | 70 | |
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[4688] | 71 | REAL(wp) :: ztmelts ! local scalar |
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[6416] | 72 | REAL(wp) :: zdum |
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[1572] | 73 | REAL(wp) :: zfracs ! fractionation coefficient for bottom salt entrapment |
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| 74 | REAL(wp) :: zswi1 ! switch for computation of bottom salinity |
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| 75 | REAL(wp) :: zswi12 ! switch for computation of bottom salinity |
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| 76 | REAL(wp) :: zswi2 ! switch for computation of bottom salinity |
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| 77 | REAL(wp) :: zgrr ! bottom growth rate |
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[4688] | 78 | REAL(wp) :: zt_i_new ! bottom formation temperature |
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| 79 | |
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| 80 | REAL(wp) :: zQm ! enthalpy exchanged with the ocean (J/m2), >0 towards the ocean |
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| 81 | REAL(wp) :: zEi ! specific enthalpy of sea ice (J/kg) |
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| 82 | REAL(wp) :: zEw ! specific enthalpy of exchanged water (J/kg) |
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| 83 | REAL(wp) :: zdE ! specific enthalpy difference (J/kg) |
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| 84 | REAL(wp) :: zfmdt ! exchange mass flux x time step (J/m2), >0 towards the ocean |
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| 85 | |
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[8373] | 86 | REAL(wp), DIMENSION(jpij) :: zqprec ! energy of fallen snow (J.m-3) |
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| 87 | REAL(wp), DIMENSION(jpij) :: zq_su ! heat for surface ablation (J.m-2) |
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| 88 | REAL(wp), DIMENSION(jpij) :: zq_bo ! heat for bottom ablation (J.m-2) |
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| 89 | REAL(wp), DIMENSION(jpij) :: zq_rema ! remaining heat at the end of the routine (J.m-2) |
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| 90 | REAL(wp), DIMENSION(jpij) :: zf_tt ! Heat budget to determine melting or freezing(W.m-2) |
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| 91 | REAL(wp), DIMENSION(jpij) :: zevap_rema ! remaining mass flux from sublimation (kg.m-2) |
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[3294] | 92 | |
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[8373] | 93 | REAL(wp), DIMENSION(jpij) :: zdh_s_mel ! snow melt |
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| 94 | REAL(wp), DIMENSION(jpij) :: zdh_s_pre ! snow precipitation |
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| 95 | REAL(wp), DIMENSION(jpij) :: zdh_s_sub ! snow sublimation |
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[3294] | 96 | |
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[8373] | 97 | REAL(wp), DIMENSION(jpij,nlay_i) :: zdeltah |
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| 98 | REAL(wp), DIMENSION(jpij,nlay_i) :: zh_i ! ice layer thickness |
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| 99 | INTEGER , DIMENSION(jpij,nlay_i) :: icount ! number of layers vanished by melting |
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[3294] | 100 | |
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[8373] | 101 | REAL(wp), DIMENSION(jpij) :: zeh_i ! total ice heat content (J.m-2) |
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| 102 | REAL(wp), DIMENSION(jpij) :: zsnw ! distribution of snow after wind blowing |
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[3294] | 103 | |
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[5123] | 104 | REAL(wp) :: zswitch_sal |
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[4161] | 105 | |
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[3294] | 106 | ! Heat conservation |
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[4688] | 107 | INTEGER :: num_iter_max |
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[1572] | 108 | !!------------------------------------------------------------------ |
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[825] | 109 | |
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[5123] | 110 | ! Discriminate between varying salinity (nn_icesal=2) and prescribed cases (other values) |
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[7646] | 111 | SELECT CASE( nn_icesal ) ! varying salinity or not |
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[8373] | 112 | CASE( 1, 3 ) ; zswitch_sal = 0._wp ! prescribed salinity profile |
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| 113 | CASE( 2 ) ; zswitch_sal = 1._wp ! varying salinity profile |
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[4688] | 114 | END SELECT |
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[825] | 115 | |
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[8342] | 116 | DO ji = 1, nidx |
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[8373] | 117 | icount (ji,:) = 0 |
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| 118 | zdh_s_mel(ji) = 0._wp |
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| 119 | e_i_1d(ji,nlay_i+1) = 0._wp ! Initialize enthalpy at nlay_i+1 |
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[5167] | 120 | END DO |
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| 121 | |
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[4688] | 122 | ! initialize layer thicknesses and enthalpies |
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[8373] | 123 | h_i_old (1:nidx,0:nlay_i+1) = 0._wp |
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| 124 | eh_i_old(1:nidx,0:nlay_i+1) = 0._wp |
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[4688] | 125 | DO jk = 1, nlay_i |
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[8342] | 126 | DO ji = 1, nidx |
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[5123] | 127 | h_i_old (ji,jk) = ht_i_1d(ji) * r1_nlay_i |
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[8325] | 128 | eh_i_old(ji,jk) = e_i_1d(ji,jk) * h_i_old(ji,jk) |
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[4688] | 129 | ENDDO |
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| 130 | ENDDO |
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[921] | 131 | ! |
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| 132 | !------------------------------------------------------------------------------! |
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[4688] | 133 | ! 1) Calculate available heat for surface and bottom ablation ! |
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[921] | 134 | !------------------------------------------------------------------------------! |
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| 135 | ! |
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[8342] | 136 | DO ji = 1, nidx |
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[6416] | 137 | zdum = qns_ice_1d(ji) + ( 1._wp - i0(ji) ) * qsr_ice_1d(ji) - fc_su(ji) |
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[4990] | 138 | zf_tt(ji) = fc_bo_i(ji) + fhtur_1d(ji) + fhld_1d(ji) |
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[4688] | 139 | |
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[6416] | 140 | zq_su (ji) = MAX( 0._wp, zdum * rdt_ice ) * MAX( 0._wp , SIGN( 1._wp, t_su_1d(ji) - rt0 ) ) |
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[4688] | 141 | zq_bo (ji) = MAX( 0._wp, zf_tt(ji) * rdt_ice ) |
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| 142 | END DO |
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| 143 | |
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[921] | 144 | ! |
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| 145 | !------------------------------------------------------------------------------! |
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[4688] | 146 | ! If snow temperature is above freezing point, then snow melts |
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| 147 | ! (should not happen but sometimes it does) |
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[921] | 148 | !------------------------------------------------------------------------------! |
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[8342] | 149 | DO ji = 1, nidx |
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[5123] | 150 | IF( t_s_1d(ji,1) > rt0 ) THEN !!! Internal melting |
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[4688] | 151 | ! Contribution to heat flux to the ocean [W.m-2], < 0 |
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[8325] | 152 | hfx_res_1d(ji) = hfx_res_1d(ji) + e_s_1d(ji,1) * ht_s_1d(ji) * a_i_1d(ji) * r1_rdtice |
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[4688] | 153 | ! Contribution to mass flux |
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[8233] | 154 | wfx_snw_sum_1d(ji) = wfx_snw_sum_1d(ji) + rhosn * ht_s_1d(ji) * a_i_1d(ji) * r1_rdtice |
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[4688] | 155 | ! updates |
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[4872] | 156 | ht_s_1d(ji) = 0._wp |
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[8325] | 157 | e_s_1d (ji,1) = 0._wp |
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[5123] | 158 | t_s_1d (ji,1) = rt0 |
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[4688] | 159 | END IF |
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| 160 | END DO |
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| 161 | |
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| 162 | !------------------------------------------------------------! |
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| 163 | ! 2) Computing layer thicknesses and enthalpies. ! |
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| 164 | !------------------------------------------------------------! |
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[921] | 165 | ! |
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[825] | 166 | DO jk = 1, nlay_i |
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[8342] | 167 | DO ji = 1, nidx |
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[5123] | 168 | zh_i(ji,jk) = ht_i_1d(ji) * r1_nlay_i |
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[8325] | 169 | zeh_i(ji) = zeh_i(ji) + e_i_1d(ji,jk) * zh_i(ji,jk) |
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[825] | 170 | END DO |
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| 171 | END DO |
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[921] | 172 | ! |
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| 173 | !------------------------------------------------------------------------------| |
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| 174 | ! 3) Surface ablation and sublimation | |
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| 175 | !------------------------------------------------------------------------------| |
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| 176 | ! |
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[834] | 177 | !------------------------- |
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| 178 | ! 3.1 Snow precips / melt |
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| 179 | !------------------------- |
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[825] | 180 | ! Snow accumulation in one thermodynamic time step |
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| 181 | ! snowfall is partitionned between leads and ice |
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| 182 | ! if snow fall was uniform, a fraction (1-at_i) would fall into leads |
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| 183 | ! but because of the winds, more snow falls on leads than on sea ice |
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| 184 | ! and a greater fraction (1-at_i)^beta of the total mass of snow |
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[834] | 185 | ! (beta < 1) falls in leads. |
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[825] | 186 | ! In reality, beta depends on wind speed, |
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| 187 | ! and should decrease with increasing wind speed but here, it is |
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[834] | 188 | ! considered as a constant. an average value is 0.66 |
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[825] | 189 | ! Martin Vancoppenolle, December 2006 |
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| 190 | |
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[8342] | 191 | CALL lim_thd_snwblow( 1. - at_i_1d(1:nidx), zsnw(1:nidx) ) ! snow distribution over ice after wind blowing |
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[5487] | 192 | |
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[8373] | 193 | zdeltah(1:nidx,:) = 0._wp |
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[8342] | 194 | DO ji = 1, nidx |
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[4688] | 195 | !----------- |
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| 196 | ! Snow fall |
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| 197 | !----------- |
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| 198 | ! thickness change |
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[5407] | 199 | zdh_s_pre(ji) = zsnw(ji) * sprecip_1d(ji) * rdt_ice * r1_rhosn / at_i_1d(ji) |
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| 200 | ! enthalpy of the precip (>0, J.m-3) |
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| 201 | zqprec (ji) = - qprec_ice_1d(ji) |
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[4688] | 202 | IF( sprecip_1d(ji) == 0._wp ) zqprec(ji) = 0._wp |
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| 203 | ! heat flux from snow precip (>0, W.m-2) |
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[4872] | 204 | hfx_spr_1d(ji) = hfx_spr_1d(ji) + zdh_s_pre(ji) * a_i_1d(ji) * zqprec(ji) * r1_rdtice |
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[4688] | 205 | ! mass flux, <0 |
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[4872] | 206 | wfx_spr_1d(ji) = wfx_spr_1d(ji) - rhosn * a_i_1d(ji) * zdh_s_pre(ji) * r1_rdtice |
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[825] | 207 | |
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[4688] | 208 | !--------------------- |
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| 209 | ! Melt of falling snow |
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| 210 | !--------------------- |
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| 211 | ! thickness change |
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[5134] | 212 | rswitch = MAX( 0._wp , SIGN( 1._wp , zqprec(ji) - epsi20 ) ) |
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[5167] | 213 | zdeltah (ji,1) = - rswitch * zq_su(ji) / MAX( zqprec(ji) , epsi20 ) |
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| 214 | zdeltah (ji,1) = MAX( - zdh_s_pre(ji), zdeltah(ji,1) ) ! bound melting |
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[4688] | 215 | ! heat used to melt snow (W.m-2, >0) |
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[5167] | 216 | hfx_snw_1d(ji) = hfx_snw_1d(ji) - zdeltah(ji,1) * a_i_1d(ji) * zqprec(ji) * r1_rdtice |
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[4688] | 217 | ! snow melting only = water into the ocean (then without snow precip), >0 |
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[8233] | 218 | wfx_snw_sum_1d(ji) = wfx_snw_sum_1d(ji) - rhosn * a_i_1d(ji) * zdeltah(ji,1) * r1_rdtice |
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[5167] | 219 | ! updates available heat + precipitations after melting |
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| 220 | zq_su (ji) = MAX( 0._wp , zq_su (ji) + zdeltah(ji,1) * zqprec(ji) ) |
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| 221 | zdh_s_pre (ji) = zdh_s_pre(ji) + zdeltah(ji,1) |
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[4688] | 222 | |
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[5167] | 223 | ! update thickness |
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| 224 | ht_s_1d(ji) = MAX( 0._wp , ht_s_1d(ji) + zdh_s_pre(ji) ) |
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[825] | 225 | END DO |
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| 226 | |
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[5167] | 227 | ! If heat still available (zq_su > 0), then melt more snow |
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[8373] | 228 | zdeltah(1:nidx,:) = 0._wp |
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[825] | 229 | DO jk = 1, nlay_s |
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[8342] | 230 | DO ji = 1, nidx |
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[4688] | 231 | ! thickness change |
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[4990] | 232 | rswitch = 1._wp - MAX( 0._wp, SIGN( 1._wp, - ht_s_1d(ji) ) ) |
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[8325] | 233 | rswitch = rswitch * ( MAX( 0._wp, SIGN( 1._wp, e_s_1d(ji,jk) - epsi20 ) ) ) |
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| 234 | zdeltah (ji,jk) = - rswitch * zq_su(ji) / MAX( e_s_1d(ji,jk), epsi20 ) |
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[5167] | 235 | zdeltah (ji,jk) = MAX( zdeltah(ji,jk) , - ht_s_1d(ji) ) ! bound melting |
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[4688] | 236 | zdh_s_mel(ji) = zdh_s_mel(ji) + zdeltah(ji,jk) |
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| 237 | ! heat used to melt snow(W.m-2, >0) |
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[8325] | 238 | hfx_snw_1d(ji) = hfx_snw_1d(ji) - zdeltah(ji,jk) * a_i_1d(ji) * e_s_1d(ji,jk) * r1_rdtice |
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[4688] | 239 | ! snow melting only = water into the ocean (then without snow precip) |
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[8233] | 240 | wfx_snw_sum_1d(ji) = wfx_snw_sum_1d(ji) - rhosn * a_i_1d(ji) * zdeltah(ji,jk) * r1_rdtice |
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[4688] | 241 | ! updates available heat + thickness |
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[8325] | 242 | zq_su (ji) = MAX( 0._wp , zq_su (ji) + zdeltah(ji,jk) * e_s_1d(ji,jk) ) |
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[4872] | 243 | ht_s_1d(ji) = MAX( 0._wp , ht_s_1d(ji) + zdeltah(ji,jk) ) |
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[1572] | 244 | END DO |
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| 245 | END DO |
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[825] | 246 | |
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[6416] | 247 | !------------------------------ |
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| 248 | ! 3.2 Sublimation (part1: snow) |
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| 249 | !------------------------------ |
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[4688] | 250 | ! qla_ice is always >=0 (upwards), heat goes to the atmosphere, therefore snow sublimates |
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[8414] | 251 | ! clem comment: not counted in mass/heat exchange in iceupdate.F90 since this is an exchange with atm. (not ocean) |
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[8373] | 252 | zdeltah(1:nidx,:) = 0._wp |
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[8342] | 253 | DO ji = 1, nidx |
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[6416] | 254 | zdh_s_sub(ji) = MAX( - ht_s_1d(ji) , - evap_ice_1d(ji) * r1_rhosn * rdt_ice ) |
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| 255 | ! remaining evap in kg.m-2 (used for ice melting later on) |
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| 256 | zevap_rema(ji) = evap_ice_1d(ji) * rdt_ice + zdh_s_sub(ji) * rhosn |
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| 257 | ! Heat flux by sublimation [W.m-2], < 0 (sublimate first snow that had fallen, then pre-existing snow) |
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[5407] | 258 | zdeltah(ji,1) = MAX( zdh_s_sub(ji), - zdh_s_pre(ji) ) |
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[8325] | 259 | hfx_sub_1d(ji) = hfx_sub_1d(ji) + ( zdeltah(ji,1) * zqprec(ji) + ( zdh_s_sub(ji) - zdeltah(ji,1) ) * e_s_1d(ji,1) & |
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[5407] | 260 | & ) * a_i_1d(ji) * r1_rdtice |
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| 261 | ! Mass flux by sublimation |
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[8239] | 262 | wfx_snw_sub_1d(ji) = wfx_snw_sub_1d(ji) - rhosn * a_i_1d(ji) * zdh_s_sub(ji) * r1_rdtice |
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| 263 | |
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[5407] | 264 | ! new snow thickness |
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| 265 | ht_s_1d(ji) = MAX( 0._wp , ht_s_1d(ji) + zdh_s_sub(ji) ) |
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| 266 | ! update precipitations after sublimation and correct sublimation |
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| 267 | zdh_s_pre(ji) = zdh_s_pre(ji) + zdeltah(ji,1) |
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| 268 | zdh_s_sub(ji) = zdh_s_sub(ji) - zdeltah(ji,1) |
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| 269 | END DO |
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| 270 | |
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[4688] | 271 | ! --- Update snow diags --- ! |
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[8342] | 272 | DO ji = 1, nidx |
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[5167] | 273 | dh_s_tot(ji) = zdh_s_mel(ji) + zdh_s_pre(ji) + zdh_s_sub(ji) |
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| 274 | END DO |
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[825] | 275 | |
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[4688] | 276 | !------------------------------------------- |
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| 277 | ! 3.3 Update temperature, energy |
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| 278 | !------------------------------------------- |
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| 279 | ! new temp and enthalpy of the snow (remaining snow precip + remaining pre-existing snow) |
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[825] | 280 | DO jk = 1, nlay_s |
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[8342] | 281 | DO ji = 1,nidx |
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[6416] | 282 | rswitch = MAX( 0._wp , SIGN( 1._wp, ht_s_1d(ji) - epsi20 ) ) |
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[8325] | 283 | e_s_1d(ji,jk) = rswitch / MAX( ht_s_1d(ji), epsi20 ) * & |
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[6416] | 284 | & ( ( zdh_s_pre(ji) ) * zqprec(ji) + & |
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| 285 | & ( ht_s_1d(ji) - zdh_s_pre(ji) ) * rhosn * ( cpic * ( rt0 - t_s_1d(ji,jk) ) + lfus ) ) |
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[825] | 286 | END DO |
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| 287 | END DO |
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| 288 | |
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[4688] | 289 | !-------------------------- |
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| 290 | ! 3.4 Surface ice ablation |
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| 291 | !-------------------------- |
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[8373] | 292 | zdeltah(1:nidx,:) = 0._wp ! important |
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[4688] | 293 | DO jk = 1, nlay_i |
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[8342] | 294 | DO ji = 1, nidx |
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[5202] | 295 | ztmelts = - tmut * s_i_1d(ji,jk) + rt0 ! Melting point of layer k [K] |
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| 296 | |
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| 297 | IF( t_i_1d(ji,jk) >= ztmelts ) THEN !!! Internal melting |
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[4688] | 298 | |
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[8325] | 299 | zEi = - e_i_1d(ji,jk) * r1_rhoic ! Specific enthalpy of layer k [J/kg, <0] |
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[5202] | 300 | zdE = 0._wp ! Specific enthalpy difference (J/kg, <0) |
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| 301 | ! set up at 0 since no energy is needed to melt water...(it is already melted) |
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| 302 | zdeltah(ji,jk) = MIN( 0._wp , - zh_i(ji,jk) ) ! internal melting occurs when the internal temperature is above freezing |
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| 303 | ! this should normally not happen, but sometimes, heat diffusion leads to this |
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| 304 | zfmdt = - zdeltah(ji,jk) * rhoic ! Mass flux x time step > 0 |
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| 305 | |
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| 306 | dh_i_surf(ji) = dh_i_surf(ji) + zdeltah(ji,jk) ! Cumulate surface melt |
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| 307 | |
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| 308 | zfmdt = - rhoic * zdeltah(ji,jk) ! Recompute mass flux [kg/m2, >0] |
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[4688] | 309 | |
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[5202] | 310 | ! Contribution to heat flux to the ocean [W.m-2], <0 (ice enthalpy zEi is "sent" to the ocean) |
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| 311 | hfx_res_1d(ji) = hfx_res_1d(ji) + zfmdt * a_i_1d(ji) * zEi * r1_rdtice |
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| 312 | |
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| 313 | ! Contribution to salt flux (clem: using sm_i_1d and not s_i_1d(jk) is ok) |
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| 314 | sfx_res_1d(ji) = sfx_res_1d(ji) - rhoic * a_i_1d(ji) * zdeltah(ji,jk) * sm_i_1d(ji) * r1_rdtice |
---|
| 315 | |
---|
| 316 | ! Contribution to mass flux |
---|
| 317 | wfx_res_1d(ji) = wfx_res_1d(ji) - rhoic * a_i_1d(ji) * zdeltah(ji,jk) * r1_rdtice |
---|
[4688] | 318 | |
---|
[5202] | 319 | ELSE !!! Surface melting |
---|
| 320 | |
---|
[8325] | 321 | zEi = - e_i_1d(ji,jk) * r1_rhoic ! Specific enthalpy of layer k [J/kg, <0] |
---|
[5202] | 322 | zEw = rcp * ( ztmelts - rt0 ) ! Specific enthalpy of resulting meltwater [J/kg, <0] |
---|
| 323 | zdE = zEi - zEw ! Specific enthalpy difference < 0 |
---|
| 324 | |
---|
| 325 | zfmdt = - zq_su(ji) / zdE ! Mass flux to the ocean [kg/m2, >0] |
---|
| 326 | |
---|
| 327 | zdeltah(ji,jk) = - zfmdt * r1_rhoic ! Melt of layer jk [m, <0] |
---|
| 328 | |
---|
| 329 | 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] |
---|
| 330 | |
---|
| 331 | zq_su(ji) = MAX( 0._wp , zq_su(ji) - zdeltah(ji,jk) * rhoic * zdE ) ! update available heat |
---|
| 332 | |
---|
| 333 | dh_i_surf(ji) = dh_i_surf(ji) + zdeltah(ji,jk) ! Cumulate surface melt |
---|
| 334 | |
---|
| 335 | zfmdt = - rhoic * zdeltah(ji,jk) ! Recompute mass flux [kg/m2, >0] |
---|
| 336 | |
---|
| 337 | zQm = zfmdt * zEw ! Energy of the melt water sent to the ocean [J/m2, <0] |
---|
| 338 | |
---|
[6416] | 339 | ! Contribution to salt flux >0 (clem: using sm_i_1d and not s_i_1d(jk) is ok) |
---|
[5202] | 340 | sfx_sum_1d(ji) = sfx_sum_1d(ji) - rhoic * a_i_1d(ji) * zdeltah(ji,jk) * sm_i_1d(ji) * r1_rdtice |
---|
| 341 | |
---|
| 342 | ! Contribution to heat flux [W.m-2], < 0 |
---|
| 343 | hfx_thd_1d(ji) = hfx_thd_1d(ji) + zfmdt * a_i_1d(ji) * zEw * r1_rdtice |
---|
| 344 | |
---|
| 345 | ! Total heat flux used in this process [W.m-2], > 0 |
---|
| 346 | hfx_sum_1d(ji) = hfx_sum_1d(ji) - zfmdt * a_i_1d(ji) * zdE * r1_rdtice |
---|
| 347 | |
---|
| 348 | ! Contribution to mass flux |
---|
| 349 | wfx_sum_1d(ji) = wfx_sum_1d(ji) - rhoic * a_i_1d(ji) * zdeltah(ji,jk) * r1_rdtice |
---|
| 350 | |
---|
[5167] | 351 | END IF |
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[6416] | 352 | ! ---------------------- |
---|
| 353 | ! Sublimation part2: ice |
---|
| 354 | ! ---------------------- |
---|
| 355 | zdum = MAX( - ( zh_i(ji,jk) + zdeltah(ji,jk) ) , - zevap_rema(ji) * r1_rhoic ) |
---|
| 356 | zdeltah(ji,jk) = zdeltah(ji,jk) + zdum |
---|
| 357 | dh_i_sub(ji) = dh_i_sub(ji) + zdum |
---|
| 358 | ! Salt flux > 0 (clem2016: flux is sent to the ocean for simplicity but salt should remain in the ice except if all ice is melted. |
---|
| 359 | ! It must be corrected at some point) |
---|
| 360 | sfx_sub_1d(ji) = sfx_sub_1d(ji) - rhoic * a_i_1d(ji) * zdum * sm_i_1d(ji) * r1_rdtice |
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| 361 | ! Heat flux [W.m-2], < 0 |
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[8325] | 362 | hfx_sub_1d(ji) = hfx_sub_1d(ji) + zdum * e_i_1d(ji,jk) * a_i_1d(ji) * r1_rdtice |
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[6416] | 363 | ! Mass flux > 0 |
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[8239] | 364 | wfx_ice_sub_1d(ji) = wfx_ice_sub_1d(ji) - rhoic * a_i_1d(ji) * zdum * r1_rdtice |
---|
| 365 | |
---|
[6416] | 366 | ! update remaining mass flux |
---|
| 367 | zevap_rema(ji) = zevap_rema(ji) + zdum * rhoic |
---|
| 368 | |
---|
[4688] | 369 | ! record which layers have disappeared (for bottom melting) |
---|
| 370 | ! => icount=0 : no layer has vanished |
---|
| 371 | ! => icount=5 : 5 layers have vanished |
---|
[5202] | 372 | rswitch = MAX( 0._wp , SIGN( 1._wp , - ( zh_i(ji,jk) + zdeltah(ji,jk) ) ) ) |
---|
| 373 | icount(ji,jk) = NINT( rswitch ) |
---|
| 374 | zh_i(ji,jk) = MAX( 0._wp , zh_i(ji,jk) + zdeltah(ji,jk) ) |
---|
[6416] | 375 | |
---|
[4688] | 376 | ! update heat content (J.m-2) and layer thickness |
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[8325] | 377 | eh_i_old(ji,jk) = eh_i_old(ji,jk) + zdeltah(ji,jk) * e_i_1d(ji,jk) |
---|
[4688] | 378 | h_i_old (ji,jk) = h_i_old (ji,jk) + zdeltah(ji,jk) |
---|
[825] | 379 | END DO |
---|
[921] | 380 | END DO |
---|
[4688] | 381 | ! update ice thickness |
---|
[8342] | 382 | DO ji = 1, nidx |
---|
[6416] | 383 | ht_i_1d(ji) = MAX( 0._wp , ht_i_1d(ji) + dh_i_surf(ji) + dh_i_sub(ji) ) |
---|
[4688] | 384 | END DO |
---|
[825] | 385 | |
---|
[6416] | 386 | ! remaining "potential" evap is sent to ocean |
---|
[8342] | 387 | DO ji = 1, nidx |
---|
[8326] | 388 | 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) |
---|
[6416] | 389 | END DO |
---|
| 390 | |
---|
[921] | 391 | ! |
---|
| 392 | !------------------------------------------------------------------------------! |
---|
| 393 | ! 4) Basal growth / melt ! |
---|
| 394 | !------------------------------------------------------------------------------! |
---|
| 395 | ! |
---|
[4688] | 396 | !------------------ |
---|
| 397 | ! 4.1 Basal growth |
---|
| 398 | !------------------ |
---|
| 399 | ! Basal growth is driven by heat imbalance at the ice-ocean interface, |
---|
| 400 | ! between the inner conductive flux (fc_bo_i), from the open water heat flux |
---|
| 401 | ! (fhld) and the turbulent ocean flux (fhtur). |
---|
| 402 | ! fc_bo_i is positive downwards. fhtur and fhld are positive to the ice |
---|
[825] | 403 | |
---|
[4688] | 404 | ! If salinity varies in time, an iterative procedure is required, because |
---|
| 405 | ! the involved quantities are inter-dependent. |
---|
| 406 | ! Basal growth (dh_i_bott) depends upon new ice specific enthalpy (zEi), |
---|
| 407 | ! which depends on forming ice salinity (s_i_new), which depends on dh/dt (dh_i_bott) |
---|
| 408 | ! -> need for an iterative procedure, which converges quickly |
---|
| 409 | |
---|
[5167] | 410 | num_iter_max = 1 |
---|
| 411 | IF( nn_icesal == 2 ) num_iter_max = 5 |
---|
[825] | 412 | |
---|
[4688] | 413 | ! Iterative procedure |
---|
[8342] | 414 | DO ji = 1, nidx |
---|
[8341] | 415 | IF( zf_tt(ji) < 0._wp ) THEN |
---|
| 416 | DO iter = 1, num_iter_max |
---|
[825] | 417 | |
---|
[4688] | 418 | ! New bottom ice salinity (Cox & Weeks, JGR88 ) |
---|
| 419 | !--- zswi1 if dh/dt < 2.0e-8 |
---|
| 420 | !--- zswi12 if 2.0e-8 < dh/dt < 3.6e-7 |
---|
| 421 | !--- zswi2 if dh/dt > 3.6e-7 |
---|
| 422 | zgrr = MIN( 1.0e-3, MAX ( dh_i_bott(ji) * r1_rdtice , epsi10 ) ) |
---|
| 423 | zswi2 = MAX( 0._wp , SIGN( 1._wp , zgrr - 3.6e-7 ) ) |
---|
| 424 | zswi12 = MAX( 0._wp , SIGN( 1._wp , zgrr - 2.0e-8 ) ) * ( 1.0 - zswi2 ) |
---|
| 425 | zswi1 = 1. - zswi2 * zswi12 |
---|
| 426 | zfracs = MIN ( zswi1 * 0.12 + zswi12 * ( 0.8925 + 0.0568 * LOG( 100.0 * zgrr ) ) & |
---|
| 427 | & + zswi2 * 0.26 / ( 0.26 + 0.74 * EXP ( - 724300.0 * zgrr ) ) , 0.5 ) |
---|
[825] | 428 | |
---|
[8326] | 429 | s_i_new(ji) = zswitch_sal * zfracs * sss_1d(ji) & ! New ice salinity |
---|
[4872] | 430 | + ( 1. - zswitch_sal ) * sm_i_1d(ji) |
---|
[4688] | 431 | ! New ice growth |
---|
[5123] | 432 | ztmelts = - tmut * s_i_new(ji) + rt0 ! New ice melting point (K) |
---|
[825] | 433 | |
---|
[4872] | 434 | zt_i_new = zswitch_sal * t_bo_1d(ji) + ( 1. - zswitch_sal) * t_i_1d(ji, nlay_i) |
---|
[4688] | 435 | |
---|
| 436 | zEi = cpic * ( zt_i_new - ztmelts ) & ! Specific enthalpy of forming ice (J/kg, <0) |
---|
[5123] | 437 | & - lfus * ( 1.0 - ( ztmelts - rt0 ) / ( zt_i_new - rt0 ) ) & |
---|
| 438 | & + rcp * ( ztmelts-rt0 ) |
---|
[4688] | 439 | |
---|
[4872] | 440 | zEw = rcp * ( t_bo_1d(ji) - rt0 ) ! Specific enthalpy of seawater (J/kg, < 0) |
---|
[4688] | 441 | |
---|
| 442 | zdE = zEi - zEw ! Specific enthalpy difference (J/kg, <0) |
---|
| 443 | |
---|
| 444 | dh_i_bott(ji) = rdt_ice * MAX( 0._wp , zf_tt(ji) / ( zdE * rhoic ) ) |
---|
| 445 | |
---|
[8325] | 446 | e_i_1d(ji,nlay_i+1) = -zEi * rhoic ! New ice energy of melting (J/m3, >0) |
---|
[4688] | 447 | |
---|
[8341] | 448 | END DO |
---|
| 449 | ! Contribution to Energy and Salt Fluxes |
---|
[4688] | 450 | zfmdt = - rhoic * dh_i_bott(ji) ! Mass flux x time step (kg/m2, < 0) |
---|
| 451 | |
---|
[5123] | 452 | ztmelts = - tmut * s_i_new(ji) + rt0 ! New ice melting point (K) |
---|
[4688] | 453 | |
---|
[4872] | 454 | zt_i_new = zswitch_sal * t_bo_1d(ji) + ( 1. - zswitch_sal) * t_i_1d(ji, nlay_i) |
---|
[4688] | 455 | |
---|
| 456 | zEi = cpic * ( zt_i_new - ztmelts ) & ! Specific enthalpy of forming ice (J/kg, <0) |
---|
[5123] | 457 | & - lfus * ( 1.0 - ( ztmelts - rt0 ) / ( zt_i_new - rt0 ) ) & |
---|
| 458 | & + rcp * ( ztmelts-rt0 ) |
---|
[4688] | 459 | |
---|
[4872] | 460 | zEw = rcp * ( t_bo_1d(ji) - rt0 ) ! Specific enthalpy of seawater (J/kg, < 0) |
---|
[4688] | 461 | |
---|
| 462 | zdE = zEi - zEw ! Specific enthalpy difference (J/kg, <0) |
---|
| 463 | |
---|
| 464 | ! Contribution to heat flux to the ocean [W.m-2], >0 |
---|
[4872] | 465 | hfx_thd_1d(ji) = hfx_thd_1d(ji) + zfmdt * a_i_1d(ji) * zEw * r1_rdtice |
---|
[4688] | 466 | |
---|
| 467 | ! Total heat flux used in this process [W.m-2], <0 |
---|
[4872] | 468 | hfx_bog_1d(ji) = hfx_bog_1d(ji) - zfmdt * a_i_1d(ji) * zdE * r1_rdtice |
---|
[4688] | 469 | |
---|
| 470 | ! Contribution to salt flux, <0 |
---|
[5167] | 471 | sfx_bog_1d(ji) = sfx_bog_1d(ji) - rhoic * a_i_1d(ji) * dh_i_bott(ji) * s_i_new(ji) * r1_rdtice |
---|
[4688] | 472 | |
---|
| 473 | ! Contribution to mass flux, <0 |
---|
[4872] | 474 | wfx_bog_1d(ji) = wfx_bog_1d(ji) - rhoic * a_i_1d(ji) * dh_i_bott(ji) * r1_rdtice |
---|
[4688] | 475 | |
---|
| 476 | ! update heat content (J.m-2) and layer thickness |
---|
[8325] | 477 | eh_i_old(ji,nlay_i+1) = eh_i_old(ji,nlay_i+1) + dh_i_bott(ji) * e_i_1d(ji,nlay_i+1) |
---|
[4688] | 478 | h_i_old (ji,nlay_i+1) = h_i_old (ji,nlay_i+1) + dh_i_bott(ji) |
---|
[8341] | 479 | |
---|
[825] | 480 | ENDIF |
---|
[8341] | 481 | |
---|
[825] | 482 | END DO |
---|
| 483 | |
---|
[4688] | 484 | !---------------- |
---|
| 485 | ! 4.2 Basal melt |
---|
| 486 | !---------------- |
---|
[8373] | 487 | zdeltah(1:nidx,:) = 0._wp ! important |
---|
[825] | 488 | DO jk = nlay_i, 1, -1 |
---|
[8342] | 489 | DO ji = 1, nidx |
---|
[5202] | 490 | IF( zf_tt(ji) > 0._wp .AND. jk > icount(ji,jk) ) THEN ! do not calculate where layer has already disappeared by surface melting |
---|
[825] | 491 | |
---|
[5123] | 492 | ztmelts = - tmut * s_i_1d(ji,jk) + rt0 ! Melting point of layer jk (K) |
---|
[825] | 493 | |
---|
[4872] | 494 | IF( t_i_1d(ji,jk) >= ztmelts ) THEN !!! Internal melting |
---|
[825] | 495 | |
---|
[8325] | 496 | zEi = - e_i_1d(ji,jk) * r1_rhoic ! Specific enthalpy of melting ice (J/kg, <0) |
---|
[4688] | 497 | zdE = 0._wp ! Specific enthalpy difference (J/kg, <0) |
---|
| 498 | ! set up at 0 since no energy is needed to melt water...(it is already melted) |
---|
[5202] | 499 | zdeltah (ji,jk) = MIN( 0._wp , - zh_i(ji,jk) ) ! internal melting occurs when the internal temperature is above freezing |
---|
| 500 | ! this should normally not happen, but sometimes, heat diffusion leads to this |
---|
[4161] | 501 | |
---|
[4688] | 502 | dh_i_bott (ji) = dh_i_bott(ji) + zdeltah(ji,jk) |
---|
[825] | 503 | |
---|
[5202] | 504 | zfmdt = - zdeltah(ji,jk) * rhoic ! Mass flux x time step > 0 |
---|
[825] | 505 | |
---|
[4688] | 506 | ! Contribution to heat flux to the ocean [W.m-2], <0 (ice enthalpy zEi is "sent" to the ocean) |
---|
[4872] | 507 | hfx_res_1d(ji) = hfx_res_1d(ji) + zfmdt * a_i_1d(ji) * zEi * r1_rdtice |
---|
[825] | 508 | |
---|
[4872] | 509 | ! Contribution to salt flux (clem: using sm_i_1d and not s_i_1d(jk) is ok) |
---|
[5167] | 510 | sfx_res_1d(ji) = sfx_res_1d(ji) - rhoic * a_i_1d(ji) * zdeltah(ji,jk) * sm_i_1d(ji) * r1_rdtice |
---|
[4688] | 511 | |
---|
| 512 | ! Contribution to mass flux |
---|
[4872] | 513 | wfx_res_1d(ji) = wfx_res_1d(ji) - rhoic * a_i_1d(ji) * zdeltah(ji,jk) * r1_rdtice |
---|
[825] | 514 | |
---|
[4688] | 515 | ! update heat content (J.m-2) and layer thickness |
---|
[8325] | 516 | eh_i_old(ji,jk) = eh_i_old(ji,jk) + zdeltah(ji,jk) * e_i_1d(ji,jk) |
---|
[4688] | 517 | h_i_old (ji,jk) = h_i_old (ji,jk) + zdeltah(ji,jk) |
---|
[825] | 518 | |
---|
[4688] | 519 | ELSE !!! Basal melting |
---|
[825] | 520 | |
---|
[8325] | 521 | zEi = - e_i_1d(ji,jk) * r1_rhoic ! Specific enthalpy of melting ice (J/kg, <0) |
---|
[5202] | 522 | zEw = rcp * ( ztmelts - rt0 ) ! Specific enthalpy of meltwater (J/kg, <0) |
---|
| 523 | zdE = zEi - zEw ! Specific enthalpy difference (J/kg, <0) |
---|
[825] | 524 | |
---|
[5202] | 525 | zfmdt = - zq_bo(ji) / zdE ! Mass flux x time step (kg/m2, >0) |
---|
[825] | 526 | |
---|
[5202] | 527 | zdeltah(ji,jk) = - zfmdt * r1_rhoic ! Gross thickness change |
---|
[4688] | 528 | |
---|
[5202] | 529 | zdeltah(ji,jk) = MIN( 0._wp , MAX( zdeltah(ji,jk), - zh_i(ji,jk) ) ) ! bound thickness change |
---|
[4688] | 530 | |
---|
[5202] | 531 | zq_bo(ji) = MAX( 0._wp , zq_bo(ji) - zdeltah(ji,jk) * rhoic * zdE ) ! update available heat. MAX is necessary for roundup errors |
---|
[4688] | 532 | |
---|
[5202] | 533 | dh_i_bott(ji) = dh_i_bott(ji) + zdeltah(ji,jk) ! Update basal melt |
---|
[4688] | 534 | |
---|
[5202] | 535 | zfmdt = - zdeltah(ji,jk) * rhoic ! Mass flux x time step > 0 |
---|
[4688] | 536 | |
---|
[5202] | 537 | zQm = zfmdt * zEw ! Heat exchanged with ocean |
---|
[4688] | 538 | |
---|
| 539 | ! Contribution to heat flux to the ocean [W.m-2], <0 |
---|
[5202] | 540 | hfx_thd_1d(ji) = hfx_thd_1d(ji) + zfmdt * a_i_1d(ji) * zEw * r1_rdtice |
---|
[4688] | 541 | |
---|
[4872] | 542 | ! Contribution to salt flux (clem: using sm_i_1d and not s_i_1d(jk) is ok) |
---|
[5202] | 543 | sfx_bom_1d(ji) = sfx_bom_1d(ji) - rhoic * a_i_1d(ji) * zdeltah(ji,jk) * sm_i_1d(ji) * r1_rdtice |
---|
[4688] | 544 | |
---|
| 545 | ! Total heat flux used in this process [W.m-2], >0 |
---|
[5202] | 546 | hfx_bom_1d(ji) = hfx_bom_1d(ji) - zfmdt * a_i_1d(ji) * zdE * r1_rdtice |
---|
[4688] | 547 | |
---|
| 548 | ! Contribution to mass flux |
---|
[5202] | 549 | wfx_bom_1d(ji) = wfx_bom_1d(ji) - rhoic * a_i_1d(ji) * zdeltah(ji,jk) * r1_rdtice |
---|
[4688] | 550 | |
---|
| 551 | ! update heat content (J.m-2) and layer thickness |
---|
[8325] | 552 | eh_i_old(ji,jk) = eh_i_old(ji,jk) + zdeltah(ji,jk) * e_i_1d(ji,jk) |
---|
[4688] | 553 | h_i_old (ji,jk) = h_i_old (ji,jk) + zdeltah(ji,jk) |
---|
| 554 | ENDIF |
---|
| 555 | |
---|
| 556 | ENDIF |
---|
[5123] | 557 | END DO |
---|
| 558 | END DO |
---|
[4688] | 559 | |
---|
[825] | 560 | !------------------------------------------- |
---|
[4688] | 561 | ! Update temperature, energy |
---|
[825] | 562 | !------------------------------------------- |
---|
[8342] | 563 | DO ji = 1, nidx |
---|
[4872] | 564 | ht_i_1d(ji) = MAX( 0._wp , ht_i_1d(ji) + dh_i_bott(ji) ) |
---|
[4688] | 565 | END DO |
---|
[825] | 566 | |
---|
[4688] | 567 | !------------------------------------------- |
---|
| 568 | ! 5. What to do with remaining energy |
---|
| 569 | !------------------------------------------- |
---|
| 570 | ! If heat still available for melting and snow remains, then melt more snow |
---|
| 571 | !------------------------------------------- |
---|
[8373] | 572 | zdeltah(1:nidx,:) = 0._wp ! important |
---|
[8342] | 573 | DO ji = 1, nidx |
---|
[4688] | 574 | zq_rema(ji) = zq_su(ji) + zq_bo(ji) |
---|
[5128] | 575 | rswitch = 1._wp - MAX( 0._wp, SIGN( 1._wp, - ht_s_1d(ji) ) ) ! =1 if snow |
---|
[8325] | 576 | rswitch = rswitch * MAX( 0._wp, SIGN( 1._wp, e_s_1d(ji,1) - epsi20 ) ) |
---|
| 577 | zdeltah (ji,1) = - rswitch * zq_rema(ji) / MAX( e_s_1d(ji,1), epsi20 ) |
---|
[5128] | 578 | zdeltah (ji,1) = MIN( 0._wp , MAX( zdeltah(ji,1) , - ht_s_1d(ji) ) ) ! bound melting |
---|
| 579 | dh_s_tot (ji) = dh_s_tot(ji) + zdeltah(ji,1) |
---|
| 580 | ht_s_1d (ji) = ht_s_1d(ji) + zdeltah(ji,1) |
---|
| 581 | |
---|
[8325] | 582 | zq_rema(ji) = zq_rema(ji) + zdeltah(ji,1) * e_s_1d(ji,1) ! update available heat (J.m-2) |
---|
[5128] | 583 | ! heat used to melt snow |
---|
[8325] | 584 | hfx_snw_1d(ji) = hfx_snw_1d(ji) - zdeltah(ji,1) * a_i_1d(ji) * e_s_1d(ji,1) * r1_rdtice ! W.m-2 (>0) |
---|
[5128] | 585 | ! Contribution to mass flux |
---|
[8233] | 586 | wfx_snw_sum_1d(ji) = wfx_snw_sum_1d(ji) - rhosn * a_i_1d(ji) * zdeltah(ji,1) * r1_rdtice |
---|
[5128] | 587 | ! |
---|
[4688] | 588 | ! Remaining heat flux (W.m-2) is sent to the ocean heat budget |
---|
[8326] | 589 | hfx_out_1d(ji) = hfx_out_1d(ji) + ( zq_rema(ji) * a_i_1d(ji) ) * r1_rdtice |
---|
[825] | 590 | |
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[7646] | 591 | IF( ln_limctl .AND. zq_rema(ji) < 0. .AND. lwp ) WRITE(numout,*) 'ALERTE zq_rema <0 = ', zq_rema(ji) |
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[4688] | 592 | END DO |
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[8239] | 593 | |
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[921] | 594 | ! |
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| 595 | !------------------------------------------------------------------------------| |
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| 596 | ! 6) Snow-Ice formation | |
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| 597 | !------------------------------------------------------------------------------| |
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[1572] | 598 | ! When snow load excesses Archimede's limit, snow-ice interface goes down under sea-level, |
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| 599 | ! flooding of seawater transforms snow into ice dh_snowice is positive for the ice |
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[8342] | 600 | DO ji = 1, nidx |
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[1572] | 601 | ! |
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[4872] | 602 | dh_snowice(ji) = MAX( 0._wp , ( rhosn * ht_s_1d(ji) + (rhoic-rau0) * ht_i_1d(ji) ) / ( rhosn+rau0-rhoic ) ) |
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[825] | 603 | |
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[5167] | 604 | ht_i_1d(ji) = ht_i_1d(ji) + dh_snowice(ji) |
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| 605 | ht_s_1d(ji) = ht_s_1d(ji) - dh_snowice(ji) |
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[825] | 606 | |
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[4688] | 607 | ! Contribution to energy flux to the ocean [J/m2], >0 (if sst<0) |
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[7646] | 608 | zfmdt = ( rhosn - rhoic ) * dh_snowice(ji) ! <0 |
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[8326] | 609 | zEw = rcp * sst_1d(ji) |
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[4688] | 610 | zQm = zfmdt * zEw |
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| 611 | |
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| 612 | ! Contribution to heat flux |
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[4872] | 613 | hfx_thd_1d(ji) = hfx_thd_1d(ji) + zfmdt * a_i_1d(ji) * zEw * r1_rdtice |
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[825] | 614 | |
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[4688] | 615 | ! Contribution to salt flux |
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[8326] | 616 | sfx_sni_1d(ji) = sfx_sni_1d(ji) + sss_1d(ji) * a_i_1d(ji) * zfmdt * r1_rdtice |
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[7646] | 617 | |
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[6470] | 618 | ! virtual salt flux to keep salinity constant |
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| 619 | IF( nn_icesal == 1 .OR. nn_icesal == 3 ) THEN |
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[8326] | 620 | 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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[8369] | 621 | & - sm_i_1d(ji) * a_i_1d(ji) * dh_snowice(ji) * rhoic * r1_rdtice ! and get rn_icesal from the ocean |
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[6470] | 622 | ENDIF |
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| 623 | |
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[4688] | 624 | ! Contribution to mass flux |
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| 625 | ! All snow is thrown in the ocean, and seawater is taken to replace the volume |
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[8341] | 626 | wfx_sni_1d(ji) = wfx_sni_1d(ji) - a_i_1d(ji) * dh_snowice(ji) * rhoic * r1_rdtice |
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| 627 | wfx_snw_sni_1d(ji) = wfx_snw_sni_1d(ji) + a_i_1d(ji) * dh_snowice(ji) * rhosn * r1_rdtice |
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[4688] | 628 | |
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| 629 | ! update heat content (J.m-2) and layer thickness |
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[8325] | 630 | eh_i_old(ji,0) = eh_i_old(ji,0) + dh_snowice(ji) * e_s_1d(ji,1) + zfmdt * zEw |
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[4688] | 631 | h_i_old (ji,0) = h_i_old (ji,0) + dh_snowice(ji) |
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| 632 | |
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[5134] | 633 | END DO |
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[825] | 634 | |
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[2715] | 635 | ! |
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[4688] | 636 | !------------------------------------------- |
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| 637 | ! Update temperature, energy |
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| 638 | !------------------------------------------- |
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[8342] | 639 | DO ji = 1, nidx |
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[4990] | 640 | rswitch = 1.0 - MAX( 0._wp , SIGN( 1._wp , - ht_i_1d(ji) ) ) |
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[5123] | 641 | t_su_1d(ji) = rswitch * t_su_1d(ji) + ( 1.0 - rswitch ) * rt0 |
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[5134] | 642 | END DO |
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[4688] | 643 | |
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| 644 | DO jk = 1, nlay_s |
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[8342] | 645 | DO ji = 1,nidx |
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[4688] | 646 | ! mask enthalpy |
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[5134] | 647 | rswitch = 1._wp - MAX( 0._wp , SIGN( 1._wp, - ht_s_1d(ji) ) ) |
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[8325] | 648 | e_s_1d(ji,jk) = rswitch * e_s_1d(ji,jk) |
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| 649 | ! recalculate t_s_1d from e_s_1d |
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| 650 | t_s_1d(ji,jk) = rt0 + rswitch * ( - e_s_1d(ji,jk) / ( rhosn * cpic ) + lfus / cpic ) |
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[4688] | 651 | END DO |
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| 652 | END DO |
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[5134] | 653 | |
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| 654 | ! --- ensure that a_i = 0 where ht_i = 0 --- |
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[8369] | 655 | DO ji = 1, nidx |
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| 656 | IF( ht_i_1d(ji) == 0._wp ) a_i_1d(ji) = 0._wp |
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[8373] | 657 | END DO |
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[2715] | 658 | ! |
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[921] | 659 | END SUBROUTINE lim_thd_dh |
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[5407] | 660 | |
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| 661 | |
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| 662 | !!-------------------------------------------------------------------------- |
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| 663 | !! INTERFACE lim_thd_snwblow |
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| 664 | !! ** Purpose : Compute distribution of precip over the ice |
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| 665 | !!-------------------------------------------------------------------------- |
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| 666 | SUBROUTINE lim_thd_snwblow_2d( pin, pout ) |
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[8313] | 667 | REAL(wp), DIMENSION(:,:), INTENT(in ) :: pin ! previous fraction lead ( 1. - a_i_b ) |
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[5487] | 668 | REAL(wp), DIMENSION(:,:), INTENT(inout) :: pout |
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[5407] | 669 | pout = ( 1._wp - ( pin )**rn_betas ) |
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| 670 | END SUBROUTINE lim_thd_snwblow_2d |
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| 671 | |
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| 672 | SUBROUTINE lim_thd_snwblow_1d( pin, pout ) |
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[5487] | 673 | REAL(wp), DIMENSION(:), INTENT(in ) :: pin |
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| 674 | REAL(wp), DIMENSION(:), INTENT(inout) :: pout |
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[5407] | 675 | pout = ( 1._wp - ( pin )**rn_betas ) |
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| 676 | END SUBROUTINE lim_thd_snwblow_1d |
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| 677 | |
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[1572] | 678 | |
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[825] | 679 | #else |
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[1572] | 680 | !!---------------------------------------------------------------------- |
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| 681 | !! Default option NO LIM3 sea-ice model |
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| 682 | !!---------------------------------------------------------------------- |
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[825] | 683 | CONTAINS |
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| 684 | SUBROUTINE lim_thd_dh ! Empty routine |
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| 685 | END SUBROUTINE lim_thd_dh |
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| 686 | #endif |
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[1572] | 687 | |
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| 688 | !!====================================================================== |
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[921] | 689 | END MODULE limthd_dh |
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