[8422] | 1 | MODULE icethd_dif |
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| 2 | !!====================================================================== |
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| 3 | !! *** MODULE icethd_dif *** |
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| 4 | !! heat diffusion in sea ice |
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| 5 | !! computation of surface and inner T |
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| 6 | !!====================================================================== |
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| 7 | !! History : LIM ! 02-2003 (M. Vancoppenolle) original 1D code |
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| 8 | !! ! 06-2005 (M. Vancoppenolle) 3d version |
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| 9 | !! ! 11-2006 (X Fettweis) Vectorization by Xavier |
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| 10 | !! ! 04-2007 (M. Vancoppenolle) Energy conservation |
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| 11 | !! 4.0 ! 2011-02 (G. Madec) dynamical allocation |
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| 12 | !! - ! 2012-05 (C. Rousset) add penetration solar flux |
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| 13 | !!---------------------------------------------------------------------- |
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| 14 | #if defined key_lim3 |
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| 15 | !!---------------------------------------------------------------------- |
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| 16 | !! 'key_lim3' LIM3 sea-ice model |
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| 17 | !!---------------------------------------------------------------------- |
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| 18 | USE par_oce ! ocean parameters |
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| 19 | USE phycst ! physical constants (ocean directory) |
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[8486] | 20 | USE ice ! sea-ice: variables |
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| 21 | USE ice1D ! sea-ice: thermodynamics |
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[8422] | 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 (allows no signed zero when 'key_nosignedzero' defined) |
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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_dif ! called by ice_thd |
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| 31 | |
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| 32 | !!---------------------------------------------------------------------- |
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[8486] | 33 | !! NEMO/ICE 4.0 , NEMO Consortium (2017) |
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[8422] | 34 | !! $Id: icethd_dif.F90 8420 2017-08-08 12:18:46Z clem $ |
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| 35 | !! Software governed by the CeCILL licence (NEMOGCM/NEMO_CeCILL.txt) |
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| 36 | !!---------------------------------------------------------------------- |
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| 37 | CONTAINS |
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| 38 | |
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| 39 | SUBROUTINE ice_thd_dif |
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| 40 | !!------------------------------------------------------------------ |
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| 41 | !! *** ROUTINE ice_thd_dif *** |
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| 42 | !! ** Purpose : |
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| 43 | !! This routine determines the time evolution of snow and sea-ice |
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| 44 | !! temperature profiles. |
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| 45 | !! ** Method : |
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| 46 | !! This is done by solving the heat equation diffusion with |
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| 47 | !! a Neumann boundary condition at the surface and a Dirichlet one |
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| 48 | !! at the bottom. Solar radiation is partially absorbed into the ice. |
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| 49 | !! The specific heat and thermal conductivities depend on ice salinity |
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| 50 | !! and temperature to take into account brine pocket melting. The |
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| 51 | !! numerical |
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| 52 | !! scheme is an iterative Crank-Nicolson on a non-uniform multilayer grid |
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| 53 | !! in the ice and snow system. |
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| 54 | !! |
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| 55 | !! The successive steps of this routine are |
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| 56 | !! 1. Thermal conductivity at the interfaces of the ice layers |
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| 57 | !! 2. Internal absorbed radiation |
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| 58 | !! 3. Scale factors due to non-uniform grid |
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| 59 | !! 4. Kappa factors |
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| 60 | !! Then iterative procedure begins |
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| 61 | !! 5. specific heat in the ice |
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| 62 | !! 6. eta factors |
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| 63 | !! 7. surface flux computation |
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| 64 | !! 8. tridiagonal system terms |
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| 65 | !! 9. solving the tridiagonal system with Gauss elimination |
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| 66 | !! Iterative procedure ends according to a criterion on evolution |
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| 67 | !! of temperature |
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| 68 | !! |
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| 69 | !! ** Inputs / Ouputs : (global commons) |
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| 70 | !! surface temperature : t_su_1d |
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| 71 | !! ice/snow temperatures : t_i_1d, t_s_1d |
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| 72 | !! ice salinities : s_i_1d |
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| 73 | !! number of layers in the ice/snow: nlay_i, nlay_s |
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| 74 | !! total ice/snow thickness : ht_i_1d, ht_s_1d |
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| 75 | !!------------------------------------------------------------------ |
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[8522] | 76 | INTEGER :: ji, jk ! spatial loop index |
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[8422] | 77 | INTEGER :: numeq ! current reference number of equation |
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| 78 | INTEGER :: minnumeqmin, maxnumeqmax |
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| 79 | INTEGER :: iconv ! number of iterations in iterative procedure |
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| 80 | INTEGER :: iconv_max = 50 ! max number of iterations in iterative procedure |
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| 81 | |
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| 82 | INTEGER, DIMENSION(jpij) :: numeqmin ! reference number of top equation |
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| 83 | INTEGER, DIMENSION(jpij) :: numeqmax ! reference number of bottom equation |
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| 84 | |
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| 85 | REAL(wp) :: zg1s = 2._wp ! for the tridiagonal system |
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| 86 | REAL(wp) :: zg1 = 2._wp ! |
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| 87 | REAL(wp) :: zgamma = 18009._wp ! for specific heat |
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| 88 | REAL(wp) :: zbeta = 0.117_wp ! for thermal conductivity (could be 0.13) |
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| 89 | REAL(wp) :: zraext_s = 10._wp ! extinction coefficient of radiation in the snow |
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| 90 | REAL(wp) :: zkimin = 0.10_wp ! minimum ice thermal conductivity |
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| 91 | REAL(wp) :: ztsu_err = 1.e-5_wp ! range around which t_su is considered at 0C |
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[8522] | 92 | REAL(wp) :: zdti_bnd = 1.e-4_wp ! maximal authorized error on temperature |
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[8422] | 93 | REAL(wp) :: ztmelt_i ! ice melting temperature |
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[8518] | 94 | REAL(wp) :: z1_hsu |
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[8422] | 95 | REAL(wp) :: zdti_max ! current maximal error on temperature |
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[8518] | 96 | REAL(wp) :: zcpi ! Ice specific heat |
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| 97 | REAL(wp) :: zhfx_err, zdq ! diag errors on heat |
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[8522] | 98 | REAL(wp) :: zfac ! dummy factor |
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[8422] | 99 | |
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| 100 | REAL(wp), DIMENSION(jpij) :: isnow ! switch for presence (1) or absence (0) of snow |
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[8518] | 101 | REAL(wp), DIMENSION(jpij) :: ztsub ! surface temperature at previous iteration |
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[8522] | 102 | REAL(wp), DIMENSION(jpij) :: zh_i, z1_h_i ! ice layer thickness |
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| 103 | REAL(wp), DIMENSION(jpij) :: zh_s, z1_h_s ! snow layer thickness |
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[8422] | 104 | REAL(wp), DIMENSION(jpij) :: zfsw ! solar radiation absorbed at the surface |
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| 105 | REAL(wp), DIMENSION(jpij) :: zqns_ice_b ! solar radiation absorbed at the surface |
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| 106 | REAL(wp), DIMENSION(jpij) :: zf ! surface flux function |
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[8518] | 107 | REAL(wp), DIMENSION(jpij) :: zdqns_ice_b ! derivative of the surface flux function |
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[8422] | 108 | REAL(wp), DIMENSION(jpij) :: zftrice ! solar radiation transmitted through the ice |
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| 109 | |
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[8522] | 110 | REAL(wp), DIMENSION(jpij,nlay_i) :: ztiold ! Old temperature in the ice |
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| 111 | REAL(wp), DIMENSION(jpij,nlay_s) :: ztsold ! Old temperature in the snow |
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| 112 | REAL(wp), DIMENSION(jpij,nlay_i) :: ztib ! Temporary temperature in the ice to check the convergence |
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| 113 | REAL(wp), DIMENSION(jpij,nlay_s) :: ztsb ! Temporary temperature in the snow to check the convergence |
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[8422] | 114 | REAL(wp), DIMENSION(jpij,0:nlay_i) :: ztcond_i ! Ice thermal conductivity |
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| 115 | REAL(wp), DIMENSION(jpij,0:nlay_i) :: zradtr_i ! Radiation transmitted through the ice |
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| 116 | REAL(wp), DIMENSION(jpij,0:nlay_i) :: zradab_i ! Radiation absorbed in the ice |
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| 117 | REAL(wp), DIMENSION(jpij,0:nlay_i) :: zkappa_i ! Kappa factor in the ice |
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| 118 | REAL(wp), DIMENSION(jpij,0:nlay_i) :: zeta_i ! Eta factor in the ice |
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| 119 | REAL(wp), DIMENSION(jpij,0:nlay_s) :: zradtr_s ! Radiation transmited through the snow |
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| 120 | REAL(wp), DIMENSION(jpij,0:nlay_s) :: zradab_s ! Radiation absorbed in the snow |
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| 121 | REAL(wp), DIMENSION(jpij,0:nlay_s) :: zkappa_s ! Kappa factor in the snow |
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| 122 | REAL(wp), DIMENSION(jpij,0:nlay_s) :: zeta_s ! Eta factor in the snow |
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| 123 | REAL(wp), DIMENSION(jpij,nlay_i+3) :: zindterm ! 'Ind'ependent term |
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| 124 | REAL(wp), DIMENSION(jpij,nlay_i+3) :: zindtbis ! Temporary 'ind'ependent term |
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| 125 | REAL(wp), DIMENSION(jpij,nlay_i+3) :: zdiagbis ! Temporary 'dia'gonal term |
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| 126 | REAL(wp), DIMENSION(jpij,nlay_i+3,3) :: ztrid ! Tridiagonal system terms |
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[8518] | 127 | REAL(wp), DIMENSION(jpij) :: zq_ini ! diag errors on heat |
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[8422] | 128 | REAL(wp), DIMENSION(jpij) :: zghe ! G(he), th. conduct enhancement factor, mono-cat |
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| 129 | |
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| 130 | ! Mono-category |
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| 131 | REAL(wp) :: zepsilon ! determines thres. above which computation of G(h) is done |
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| 132 | REAL(wp) :: zhe ! dummy factor |
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[8522] | 133 | REAL(wp) :: zcnd_i ! mean sea ice thermal conductivity |
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[8422] | 134 | !!------------------------------------------------------------------ |
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| 135 | |
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| 136 | ! --- diag error on heat diffusion - PART 1 --- ! |
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| 137 | DO ji = 1, nidx |
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| 138 | zq_ini(ji) = ( SUM( e_i_1d(ji,1:nlay_i) ) * ht_i_1d(ji) * r1_nlay_i + & |
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| 139 | & SUM( e_s_1d(ji,1:nlay_s) ) * ht_s_1d(ji) * r1_nlay_s ) |
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| 140 | END DO |
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| 141 | |
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| 142 | !------------------------------------------------------------------------------! |
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| 143 | ! 1) Initialization ! |
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| 144 | !------------------------------------------------------------------------------! |
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[8522] | 145 | DO ji = 1, nidx |
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[8422] | 146 | isnow(ji)= 1._wp - MAX( 0._wp , SIGN(1._wp, - ht_s_1d(ji) ) ) ! is there snow or not |
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| 147 | ! layer thickness |
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| 148 | zh_i(ji) = ht_i_1d(ji) * r1_nlay_i |
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| 149 | zh_s(ji) = ht_s_1d(ji) * r1_nlay_s |
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| 150 | END DO |
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[8522] | 151 | ! |
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| 152 | WHERE( zh_i(1:nidx) >= epsi10 ) ; z1_h_i(1:nidx) = 1._wp / zh_i(1:nidx) |
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| 153 | ELSEWHERE ; z1_h_i(1:nidx) = 0._wp |
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| 154 | END WHERE |
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[8422] | 155 | |
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[8522] | 156 | WHERE( zh_s(1:nidx) >= epsi10 ) ; z1_h_s(1:nidx) = 1._wp / zh_s(1:nidx) |
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| 157 | ELSEWHERE ; z1_h_s(1:nidx) = 0._wp |
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| 158 | END WHERE |
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[8422] | 159 | ! |
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[8522] | 160 | ! temperatures |
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| 161 | ztsub (1:nidx) = t_su_1d(1:nidx) ! temperature at the previous iteration |
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| 162 | ztsold (1:nidx,:) = t_s_1d(1:nidx,:) ! Old snow temperature |
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| 163 | ztiold (1:nidx,:) = t_i_1d(1:nidx,:) ! Old ice temperature |
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| 164 | t_su_1d(1:nidx) = MIN( t_su_1d(1:nidx), rt0 - ztsu_err ) ! necessary |
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| 165 | ! |
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[8422] | 166 | !------------------------------------------------------------------------------| |
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[8522] | 167 | ! 2) Radiation | |
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[8422] | 168 | !------------------------------------------------------------------------------| |
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| 169 | ! |
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[8518] | 170 | z1_hsu = 1._wp / 0.1_wp ! threshold for the computation of i0 |
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[8522] | 171 | DO ji = 1, nidx |
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[8518] | 172 | !------------------- |
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| 173 | ! Computation of i0 |
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| 174 | !------------------- |
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| 175 | ! i0 describes the fraction of solar radiation which does not contribute |
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| 176 | ! to the surface energy budget but rather penetrates inside the ice. |
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| 177 | ! We assume that no radiation is transmitted through the snow |
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| 178 | ! If there is no no snow |
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| 179 | ! zfsw = (1-i0).qsr_ice is absorbed at the surface |
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| 180 | ! zftrice = io.qsr_ice is below the surface |
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| 181 | ! ftr_ice = io.qsr_ice.exp(-k(h_i)) transmitted below the ice |
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| 182 | ! fr1_i0_1d = i0 for a thin ice cover, fr1_i0_2d = i0 for a thick ice cover |
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[8522] | 183 | zfac = MAX( 0._wp , 1._wp - ( ht_i_1d(ji) * z1_hsu ) ) |
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| 184 | i0(ji) = ( 1._wp - isnow(ji) ) * ( fr1_i0_1d(ji) + zfac * fr2_i0_1d(ji) ) |
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[8422] | 185 | |
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[8518] | 186 | !------------------------------------------------------- |
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| 187 | ! Solar radiation absorbed / transmitted at the surface |
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| 188 | ! Derivative of the non solar flux |
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| 189 | !------------------------------------------------------- |
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| 190 | zfsw (ji) = qsr_ice_1d(ji) * ( 1 - i0(ji) ) ! Shortwave radiation absorbed at surface |
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| 191 | zftrice(ji) = qsr_ice_1d(ji) * i0(ji) ! Solar radiation transmitted below the surface layer |
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| 192 | zdqns_ice_b(ji) = dqns_ice_1d(ji) ! derivative of incoming nonsolar flux |
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| 193 | zqns_ice_b (ji) = qns_ice_1d(ji) ! store previous qns_ice_1d value |
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[8422] | 194 | END DO |
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| 195 | |
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| 196 | !--------------------------------------------------------- |
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| 197 | ! Transmission - absorption of solar radiation in the ice |
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| 198 | !--------------------------------------------------------- |
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[8518] | 199 | zradtr_s(1:nidx,0) = zftrice(1:nidx) |
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| 200 | DO jk = 1, nlay_s |
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[8422] | 201 | DO ji = 1, nidx |
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| 202 | ! ! radiation transmitted below the layer-th snow layer |
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[8522] | 203 | zradtr_s(ji,jk) = zradtr_s(ji,0) * EXP( - zraext_s * zh_s(ji) * REAL(jk) ) |
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[8422] | 204 | ! ! radiation absorbed by the layer-th snow layer |
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| 205 | zradab_s(ji,jk) = zradtr_s(ji,jk-1) - zradtr_s(ji,jk) |
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| 206 | END DO |
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| 207 | END DO |
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[8518] | 208 | |
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| 209 | zradtr_i(1:nidx,0) = zradtr_s(1:nidx,nlay_s) * isnow(1:nidx) + zftrice(1:nidx) * ( 1._wp - isnow(1:nidx) ) |
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| 210 | DO jk = 1, nlay_i |
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[8422] | 211 | DO ji = 1, nidx |
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| 212 | ! ! radiation transmitted below the layer-th ice layer |
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[8522] | 213 | zradtr_i(ji,jk) = zradtr_i(ji,0) * EXP( - rn_kappa_i * zh_i(ji) * REAL(jk) ) |
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[8422] | 214 | ! ! radiation absorbed by the layer-th ice layer |
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| 215 | zradab_i(ji,jk) = zradtr_i(ji,jk-1) - zradtr_i(ji,jk) |
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| 216 | END DO |
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| 217 | END DO |
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| 218 | |
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[8518] | 219 | ftr_ice_1d(1:nidx) = zradtr_i(1:nidx,nlay_i) ! record radiation transmitted below the ice |
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[8422] | 220 | |
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| 221 | !------------------------------------------------------------------------------| |
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| 222 | ! 3) Iterative procedure begins | |
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| 223 | !------------------------------------------------------------------------------| |
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| 224 | ! |
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[8522] | 225 | iconv = 0 ! number of iterations |
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| 226 | zdti_max = 1000._wp ! maximal value of error on all points |
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[8422] | 227 | DO WHILE ( zdti_max > zdti_bnd .AND. iconv < iconv_max ) |
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| 228 | ! |
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| 229 | iconv = iconv + 1 |
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| 230 | ! |
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[8522] | 231 | ztib(1:nidx,:) = t_i_1d(1:nidx,:) |
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| 232 | ztsb(1:nidx,:) = t_s_1d(1:nidx,:) |
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| 233 | ! |
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[8422] | 234 | !------------------------------------------------------------------------------| |
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| 235 | ! 4) Sea ice thermal conductivity | |
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| 236 | !------------------------------------------------------------------------------| |
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| 237 | ! |
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[8514] | 238 | IF( ln_cndi_U64 ) THEN !-- Untersteiner (1964) formula: k = k0 + beta.S/T |
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[8522] | 239 | ! |
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| 240 | DO ji = 1, nidx |
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| 241 | ztcond_i(ji,0) = rcdic + zbeta * s_i_1d(ji,1) / MIN( -epsi10, t_i_1d(ji,1) - rt0 ) |
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| 242 | ztcond_i(ji,nlay_i) = rcdic + zbeta * s_i_1d(ji,nlay_i) / MIN( -epsi10, t_bo_1d(ji) - rt0 ) |
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[8422] | 243 | END DO |
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| 244 | DO jk = 1, nlay_i-1 |
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[8522] | 245 | DO ji = 1, nidx |
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| 246 | ztcond_i(ji,jk) = rcdic + zbeta * 0.5_wp * ( s_i_1d(ji,jk) + s_i_1d(ji,jk+1) ) / & |
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| 247 | & MIN( -epsi10, 0.5_wp * (t_i_1d(ji,jk) + t_i_1d(ji,jk+1)) - rt0 ) |
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[8422] | 248 | END DO |
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| 249 | END DO |
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[8522] | 250 | ! |
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[8514] | 251 | ELSEIF( ln_cndi_P07 ) THEN !-- Pringle et al formula: k = k0 + beta1.S/T - beta2.T |
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[8522] | 252 | ! |
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| 253 | DO ji = 1, nidx |
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| 254 | ztcond_i(ji,0) = rcdic + 0.09_wp * s_i_1d(ji,1) / MIN( -epsi10, t_i_1d(ji,1) - rt0 ) & |
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| 255 | & - 0.011_wp * ( t_i_1d(ji,1) - rt0 ) |
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| 256 | ztcond_i(ji,nlay_i) = rcdic + 0.09_wp * s_i_1d(ji,nlay_i) / MIN( -epsi10, t_bo_1d(ji) - rt0 ) & |
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| 257 | & - 0.011_wp * ( t_bo_1d(ji) - rt0 ) |
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[8422] | 258 | END DO |
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| 259 | DO jk = 1, nlay_i-1 |
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[8522] | 260 | DO ji = 1, nidx |
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| 261 | ztcond_i(ji,jk) = rcdic + 0.09_wp * 0.5_wp * ( s_i_1d(ji,jk) + s_i_1d(ji,jk+1) ) / & |
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| 262 | & MIN( -epsi10, 0.5_wp * (t_i_1d(ji,jk) + t_i_1d(ji,jk+1)) - rt0 ) & |
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| 263 | & - 0.011_wp * ( 0.5_wp * (t_i_1d(ji,jk) + t_i_1d(ji,jk+1)) - rt0 ) |
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[8422] | 264 | END DO |
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| 265 | END DO |
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[8522] | 266 | ! |
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[8422] | 267 | ENDIF |
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[8522] | 268 | ztcond_i(1:nidx,:) = MAX( zkimin, ztcond_i(1:nidx,:) ) |
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[8422] | 269 | ! |
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| 270 | !------------------------------------------------------------------------------| |
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| 271 | ! 5) G(he) - enhancement of thermal conductivity in mono-category case | |
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| 272 | !------------------------------------------------------------------------------| |
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| 273 | ! |
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| 274 | ! Computation of effective thermal conductivity G(h) |
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| 275 | ! Used in mono-category case only to simulate an ITD implicitly |
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| 276 | ! Fichefet and Morales Maqueda, JGR 1997 |
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| 277 | |
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[8522] | 278 | zghe(1:nidx) = 1._wp |
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| 279 | |
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[8422] | 280 | SELECT CASE ( nn_monocat ) |
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| 281 | |
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[8522] | 282 | CASE ( 1 , 3 ) |
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[8422] | 283 | |
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| 284 | zepsilon = 0.1_wp |
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| 285 | DO ji = 1, nidx |
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| 286 | |
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| 287 | ! Mean sea ice thermal conductivity |
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[8522] | 288 | zcnd_i = SUM( ztcond_i(ji,:) ) / REAL( nlay_i+1, wp ) |
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[8422] | 289 | |
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| 290 | ! Effective thickness he (zhe) |
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[8522] | 291 | zhe = ( rn_cnd_s * ht_i_1d(ji) + zcnd_i * ht_s_1d(ji) ) / ( rn_cnd_s + zcnd_i ) |
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[8422] | 292 | |
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| 293 | ! G(he) |
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[8522] | 294 | IF( zhe >= zepsilon * 0.5_wp * EXP(1._wp) ) THEN |
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| 295 | zghe(ji) = MIN( 2._wp, 0.5_wp * ( 1._wp + LOG( 2._wp * zhe / zepsilon ) ) ) |
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| 296 | ENDIF |
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[8422] | 297 | |
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| 298 | END DO |
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| 299 | |
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| 300 | END SELECT |
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| 301 | ! |
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| 302 | !------------------------------------------------------------------------------| |
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| 303 | ! 6) kappa factors | |
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| 304 | !------------------------------------------------------------------------------| |
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| 305 | ! |
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| 306 | !--- Snow |
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[8522] | 307 | DO jk = 0, nlay_s-1 |
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| 308 | DO ji = 1, nidx |
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| 309 | zkappa_s(ji,jk) = zghe(ji) * rn_cnd_s * z1_h_s(ji) |
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[8422] | 310 | END DO |
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| 311 | END DO |
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[8522] | 312 | DO ji = 1, nidx ! Snow-ice interface |
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| 313 | zfac = 0.5_wp * ( ztcond_i(ji,0) * zh_s(ji) + rn_cnd_s * zh_i(ji) ) |
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| 314 | IF( zfac > epsi10 ) THEN |
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| 315 | zkappa_s(ji,nlay_s) = zghe(ji) * rn_cnd_s * ztcond_i(ji,0) / zfac |
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| 316 | ELSE |
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| 317 | zkappa_s(ji,nlay_s) = 0._wp |
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| 318 | ENDIF |
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| 319 | END DO |
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[8422] | 320 | |
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| 321 | !--- Ice |
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[8522] | 322 | DO jk = 0, nlay_i |
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| 323 | DO ji = 1, nidx |
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| 324 | zkappa_i(ji,jk) = zghe(ji) * ztcond_i(ji,jk) * z1_h_i(ji) |
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[8422] | 325 | END DO |
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| 326 | END DO |
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[8522] | 327 | DO ji = 1, nidx ! Snow-ice interface |
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| 328 | zkappa_i(ji,0) = zkappa_s(ji,nlay_s) * isnow(ji) + zkappa_i(ji,0) * ( 1._wp - isnow(ji) ) |
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[8422] | 329 | END DO |
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| 330 | ! |
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| 331 | !------------------------------------------------------------------------------| |
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| 332 | ! 7) Sea ice specific heat, eta factors | |
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| 333 | !------------------------------------------------------------------------------| |
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| 334 | ! |
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| 335 | DO jk = 1, nlay_i |
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[8522] | 336 | DO ji = 1, nidx |
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| 337 | zcpi = cpic + zgamma * s_i_1d(ji,jk) / MAX( ( t_i_1d(ji,jk) - rt0 ) * ( ztiold(ji,jk) - rt0 ), epsi10 ) |
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| 338 | zeta_i(ji,jk) = rdt_ice * r1_rhoic * z1_h_i(ji) / MAX( epsi10, zcpi ) |
---|
[8422] | 339 | END DO |
---|
| 340 | END DO |
---|
| 341 | |
---|
| 342 | DO jk = 1, nlay_s |
---|
[8522] | 343 | DO ji = 1, nidx |
---|
| 344 | zeta_s(ji,jk) = rdt_ice * r1_rhosn * r1_cpic * z1_h_s(ji) |
---|
[8422] | 345 | END DO |
---|
| 346 | END DO |
---|
| 347 | ! |
---|
| 348 | !------------------------------------------------------------------------------| |
---|
| 349 | ! 8) surface flux computation | |
---|
| 350 | !------------------------------------------------------------------------------| |
---|
| 351 | ! |
---|
[8514] | 352 | IF ( ln_dqns_i ) THEN |
---|
[8522] | 353 | DO ji = 1, nidx |
---|
[8422] | 354 | ! update of the non solar flux according to the update in T_su |
---|
[8518] | 355 | qns_ice_1d(ji) = qns_ice_1d(ji) + dqns_ice_1d(ji) * ( t_su_1d(ji) - ztsub(ji) ) |
---|
[8422] | 356 | END DO |
---|
| 357 | ENDIF |
---|
| 358 | |
---|
[8522] | 359 | DO ji = 1, nidx |
---|
| 360 | zf(ji) = zfsw(ji) + qns_ice_1d(ji) ! incoming = net absorbed solar radiation + non solar total flux (LWup, LWdw, SH, LH) |
---|
[8422] | 361 | END DO |
---|
| 362 | ! |
---|
| 363 | !------------------------------------------------------------------------------| |
---|
| 364 | ! 9) tridiagonal system terms | |
---|
| 365 | !------------------------------------------------------------------------------| |
---|
| 366 | ! |
---|
| 367 | !!layer denotes the number of the layer in the snow or in the ice |
---|
| 368 | !!numeq denotes the reference number of the equation in the tridiagonal |
---|
| 369 | !!system, terms of tridiagonal system are indexed as following : |
---|
| 370 | !!1 is subdiagonal term, 2 is diagonal and 3 is superdiagonal one |
---|
| 371 | |
---|
| 372 | !!ice interior terms (top equation has the same form as the others) |
---|
| 373 | |
---|
| 374 | DO numeq=1,nlay_i+3 |
---|
[8522] | 375 | DO ji = 1, nidx |
---|
[8422] | 376 | ztrid(ji,numeq,1) = 0. |
---|
| 377 | ztrid(ji,numeq,2) = 0. |
---|
| 378 | ztrid(ji,numeq,3) = 0. |
---|
| 379 | zindterm(ji,numeq)= 0. |
---|
| 380 | zindtbis(ji,numeq)= 0. |
---|
| 381 | zdiagbis(ji,numeq)= 0. |
---|
| 382 | ENDDO |
---|
| 383 | ENDDO |
---|
| 384 | |
---|
| 385 | DO numeq = nlay_s + 2, nlay_s + nlay_i |
---|
[8522] | 386 | DO ji = 1, nidx |
---|
[8422] | 387 | jk = numeq - nlay_s - 1 |
---|
| 388 | ztrid(ji,numeq,1) = - zeta_i(ji,jk) * zkappa_i(ji,jk-1) |
---|
| 389 | ztrid(ji,numeq,2) = 1.0 + zeta_i(ji,jk) * ( zkappa_i(ji,jk-1) + zkappa_i(ji,jk) ) |
---|
| 390 | ztrid(ji,numeq,3) = - zeta_i(ji,jk) * zkappa_i(ji,jk) |
---|
[8522] | 391 | zindterm(ji,numeq) = ztiold(ji,jk) + zeta_i(ji,jk) * zradab_i(ji,jk) |
---|
[8422] | 392 | END DO |
---|
| 393 | ENDDO |
---|
| 394 | |
---|
| 395 | numeq = nlay_s + nlay_i + 1 |
---|
[8522] | 396 | DO ji = 1, nidx |
---|
[8422] | 397 | !!ice bottom term |
---|
| 398 | ztrid(ji,numeq,1) = - zeta_i(ji,nlay_i)*zkappa_i(ji,nlay_i-1) |
---|
| 399 | ztrid(ji,numeq,2) = 1.0 + zeta_i(ji,nlay_i) * ( zkappa_i(ji,nlay_i) * zg1 + zkappa_i(ji,nlay_i-1) ) |
---|
| 400 | ztrid(ji,numeq,3) = 0.0 |
---|
[8522] | 401 | zindterm(ji,numeq) = ztiold(ji,nlay_i) + zeta_i(ji,nlay_i) * & |
---|
[8422] | 402 | & ( zradab_i(ji,nlay_i) + zkappa_i(ji,nlay_i) * zg1 * t_bo_1d(ji) ) |
---|
| 403 | ENDDO |
---|
| 404 | |
---|
| 405 | |
---|
[8522] | 406 | DO ji = 1, nidx |
---|
[8422] | 407 | IF ( ht_s_1d(ji) > 0.0 ) THEN |
---|
| 408 | ! |
---|
| 409 | !------------------------------------------------------------------------------| |
---|
| 410 | ! snow-covered cells | |
---|
| 411 | !------------------------------------------------------------------------------| |
---|
| 412 | ! |
---|
| 413 | !!snow interior terms (bottom equation has the same form as the others) |
---|
| 414 | DO numeq = 3, nlay_s + 1 |
---|
| 415 | jk = numeq - 1 |
---|
| 416 | ztrid(ji,numeq,1) = - zeta_s(ji,jk) * zkappa_s(ji,jk-1) |
---|
| 417 | ztrid(ji,numeq,2) = 1.0 + zeta_s(ji,jk) * ( zkappa_s(ji,jk-1) + zkappa_s(ji,jk) ) |
---|
| 418 | ztrid(ji,numeq,3) = - zeta_s(ji,jk)*zkappa_s(ji,jk) |
---|
[8522] | 419 | zindterm(ji,numeq) = ztsold(ji,jk) + zeta_s(ji,jk) * zradab_s(ji,jk) |
---|
[8422] | 420 | END DO |
---|
| 421 | |
---|
| 422 | !!case of only one layer in the ice (ice equation is altered) |
---|
[8522] | 423 | IF ( nlay_i == 1 ) THEN |
---|
[8422] | 424 | ztrid(ji,nlay_s+2,3) = 0.0 |
---|
| 425 | zindterm(ji,nlay_s+2) = zindterm(ji,nlay_s+2) + zkappa_i(ji,1) * t_bo_1d(ji) |
---|
| 426 | ENDIF |
---|
| 427 | |
---|
| 428 | IF ( t_su_1d(ji) < rt0 ) THEN |
---|
| 429 | |
---|
| 430 | !------------------------------------------------------------------------------| |
---|
| 431 | ! case 1 : no surface melting - snow present | |
---|
| 432 | !------------------------------------------------------------------------------| |
---|
| 433 | numeqmin(ji) = 1 |
---|
| 434 | numeqmax(ji) = nlay_i + nlay_s + 1 |
---|
| 435 | |
---|
| 436 | !!surface equation |
---|
| 437 | ztrid(ji,1,1) = 0.0 |
---|
[8518] | 438 | ztrid(ji,1,2) = zdqns_ice_b(ji) - zg1s * zkappa_s(ji,0) |
---|
[8422] | 439 | ztrid(ji,1,3) = zg1s * zkappa_s(ji,0) |
---|
[8518] | 440 | zindterm(ji,1) = zdqns_ice_b(ji) * t_su_1d(ji) - zf(ji) |
---|
[8422] | 441 | |
---|
| 442 | !!first layer of snow equation |
---|
| 443 | ztrid(ji,2,1) = - zkappa_s(ji,0) * zg1s * zeta_s(ji,1) |
---|
| 444 | ztrid(ji,2,2) = 1.0 + zeta_s(ji,1) * ( zkappa_s(ji,1) + zkappa_s(ji,0) * zg1s ) |
---|
| 445 | ztrid(ji,2,3) = - zeta_s(ji,1)* zkappa_s(ji,1) |
---|
[8522] | 446 | zindterm(ji,2) = ztsold(ji,1) + zeta_s(ji,1) * zradab_s(ji,1) |
---|
[8422] | 447 | |
---|
| 448 | ELSE |
---|
| 449 | ! |
---|
| 450 | !------------------------------------------------------------------------------| |
---|
| 451 | ! case 2 : surface is melting - snow present | |
---|
| 452 | !------------------------------------------------------------------------------| |
---|
| 453 | ! |
---|
| 454 | numeqmin(ji) = 2 |
---|
| 455 | numeqmax(ji) = nlay_i + nlay_s + 1 |
---|
| 456 | |
---|
| 457 | !!first layer of snow equation |
---|
| 458 | ztrid(ji,2,1) = 0.0 |
---|
| 459 | ztrid(ji,2,2) = 1.0 + zeta_s(ji,1) * ( zkappa_s(ji,1) + zkappa_s(ji,0) * zg1s ) |
---|
| 460 | ztrid(ji,2,3) = - zeta_s(ji,1)*zkappa_s(ji,1) |
---|
[8522] | 461 | zindterm(ji,2) = ztsold(ji,1) + zeta_s(ji,1) * & |
---|
[8422] | 462 | & ( zradab_s(ji,1) + zkappa_s(ji,0) * zg1s * t_su_1d(ji) ) |
---|
| 463 | ENDIF |
---|
| 464 | ELSE |
---|
| 465 | ! |
---|
| 466 | !------------------------------------------------------------------------------| |
---|
| 467 | ! cells without snow | |
---|
| 468 | !------------------------------------------------------------------------------| |
---|
| 469 | ! |
---|
| 470 | IF ( t_su_1d(ji) < rt0 ) THEN |
---|
| 471 | ! |
---|
| 472 | !------------------------------------------------------------------------------| |
---|
| 473 | ! case 3 : no surface melting - no snow | |
---|
| 474 | !------------------------------------------------------------------------------| |
---|
| 475 | ! |
---|
| 476 | numeqmin(ji) = nlay_s + 1 |
---|
| 477 | numeqmax(ji) = nlay_i + nlay_s + 1 |
---|
| 478 | |
---|
| 479 | !!surface equation |
---|
| 480 | ztrid(ji,numeqmin(ji),1) = 0.0 |
---|
[8518] | 481 | ztrid(ji,numeqmin(ji),2) = zdqns_ice_b(ji) - zkappa_i(ji,0)*zg1 |
---|
[8422] | 482 | ztrid(ji,numeqmin(ji),3) = zkappa_i(ji,0)*zg1 |
---|
[8518] | 483 | zindterm(ji,numeqmin(ji)) = zdqns_ice_b(ji)*t_su_1d(ji) - zf(ji) |
---|
[8422] | 484 | |
---|
| 485 | !!first layer of ice equation |
---|
| 486 | ztrid(ji,numeqmin(ji)+1,1) = - zkappa_i(ji,0) * zg1 * zeta_i(ji,1) |
---|
| 487 | ztrid(ji,numeqmin(ji)+1,2) = 1.0 + zeta_i(ji,1) * ( zkappa_i(ji,1) + zkappa_i(ji,0) * zg1 ) |
---|
| 488 | ztrid(ji,numeqmin(ji)+1,3) = - zeta_i(ji,1) * zkappa_i(ji,1) |
---|
[8522] | 489 | zindterm(ji,numeqmin(ji)+1)= ztiold(ji,1) + zeta_i(ji,1) * zradab_i(ji,1) |
---|
[8422] | 490 | |
---|
| 491 | !!case of only one layer in the ice (surface & ice equations are altered) |
---|
| 492 | |
---|
| 493 | IF ( nlay_i == 1 ) THEN |
---|
| 494 | ztrid(ji,numeqmin(ji),1) = 0.0 |
---|
[8518] | 495 | ztrid(ji,numeqmin(ji),2) = zdqns_ice_b(ji) - zkappa_i(ji,0) * 2.0 |
---|
[8422] | 496 | ztrid(ji,numeqmin(ji),3) = zkappa_i(ji,0) * 2.0 |
---|
| 497 | ztrid(ji,numeqmin(ji)+1,1) = -zkappa_i(ji,0) * 2.0 * zeta_i(ji,1) |
---|
| 498 | ztrid(ji,numeqmin(ji)+1,2) = 1.0 + zeta_i(ji,1) * ( zkappa_i(ji,0) * 2.0 + zkappa_i(ji,1) ) |
---|
| 499 | ztrid(ji,numeqmin(ji)+1,3) = 0.0 |
---|
| 500 | |
---|
[8522] | 501 | zindterm(ji,numeqmin(ji)+1) = ztiold(ji,1) + zeta_i(ji,1) * & |
---|
[8422] | 502 | & ( zradab_i(ji,1) + zkappa_i(ji,1) * t_bo_1d(ji) ) |
---|
| 503 | ENDIF |
---|
| 504 | |
---|
| 505 | ELSE |
---|
| 506 | |
---|
| 507 | ! |
---|
| 508 | !------------------------------------------------------------------------------| |
---|
| 509 | ! case 4 : surface is melting - no snow | |
---|
| 510 | !------------------------------------------------------------------------------| |
---|
| 511 | ! |
---|
| 512 | numeqmin(ji) = nlay_s + 2 |
---|
| 513 | numeqmax(ji) = nlay_i + nlay_s + 1 |
---|
| 514 | |
---|
| 515 | !!first layer of ice equation |
---|
| 516 | ztrid(ji,numeqmin(ji),1) = 0.0 |
---|
| 517 | ztrid(ji,numeqmin(ji),2) = 1.0 + zeta_i(ji,1) * ( zkappa_i(ji,1) + zkappa_i(ji,0) * zg1 ) |
---|
| 518 | ztrid(ji,numeqmin(ji),3) = - zeta_i(ji,1) * zkappa_i(ji,1) |
---|
[8522] | 519 | zindterm(ji,numeqmin(ji)) = ztiold(ji,1) + zeta_i(ji,1) * & |
---|
[8422] | 520 | & ( zradab_i(ji,1) + zkappa_i(ji,0) * zg1 * t_su_1d(ji) ) |
---|
| 521 | |
---|
| 522 | !!case of only one layer in the ice (surface & ice equations are altered) |
---|
| 523 | IF ( nlay_i == 1 ) THEN |
---|
| 524 | ztrid(ji,numeqmin(ji),1) = 0.0 |
---|
| 525 | ztrid(ji,numeqmin(ji),2) = 1.0 + zeta_i(ji,1) * ( zkappa_i(ji,0) * 2.0 + zkappa_i(ji,1) ) |
---|
| 526 | ztrid(ji,numeqmin(ji),3) = 0.0 |
---|
[8522] | 527 | zindterm(ji,numeqmin(ji)) = ztiold(ji,1) + zeta_i(ji,1) * ( zradab_i(ji,1) + zkappa_i(ji,1) * t_bo_1d(ji) ) & |
---|
[8422] | 528 | & + t_su_1d(ji) * zeta_i(ji,1) * zkappa_i(ji,0) * 2.0 |
---|
| 529 | ENDIF |
---|
| 530 | |
---|
| 531 | ENDIF |
---|
| 532 | ENDIF |
---|
| 533 | |
---|
| 534 | END DO |
---|
| 535 | ! |
---|
| 536 | !------------------------------------------------------------------------------| |
---|
| 537 | ! 10) tridiagonal system solving | |
---|
| 538 | !------------------------------------------------------------------------------| |
---|
| 539 | ! |
---|
| 540 | ! Solve the tridiagonal system with Gauss elimination method. |
---|
| 541 | ! Thomas algorithm, from Computational fluid Dynamics, J.D. ANDERSON, |
---|
| 542 | ! McGraw-Hill 1984. |
---|
| 543 | |
---|
| 544 | maxnumeqmax = 0 |
---|
| 545 | minnumeqmin = nlay_i+5 |
---|
| 546 | |
---|
[8522] | 547 | DO ji = 1, nidx |
---|
[8422] | 548 | zindtbis(ji,numeqmin(ji)) = zindterm(ji,numeqmin(ji)) |
---|
| 549 | zdiagbis(ji,numeqmin(ji)) = ztrid(ji,numeqmin(ji),2) |
---|
| 550 | minnumeqmin = MIN(numeqmin(ji),minnumeqmin) |
---|
| 551 | maxnumeqmax = MAX(numeqmax(ji),maxnumeqmax) |
---|
| 552 | END DO |
---|
| 553 | |
---|
| 554 | DO jk = minnumeqmin+1, maxnumeqmax |
---|
[8522] | 555 | DO ji = 1, nidx |
---|
[8422] | 556 | numeq = min(max(numeqmin(ji)+1,jk),numeqmax(ji)) |
---|
| 557 | zdiagbis(ji,numeq) = ztrid(ji,numeq,2) - ztrid(ji,numeq,1) * ztrid(ji,numeq-1,3) / zdiagbis(ji,numeq-1) |
---|
| 558 | zindtbis(ji,numeq) = zindterm(ji,numeq) - ztrid(ji,numeq,1) * zindtbis(ji,numeq-1) / zdiagbis(ji,numeq-1) |
---|
| 559 | END DO |
---|
| 560 | END DO |
---|
| 561 | |
---|
[8522] | 562 | DO ji = 1, nidx |
---|
[8422] | 563 | ! ice temperatures |
---|
[8522] | 564 | t_i_1d(ji,nlay_i) = zindtbis(ji,numeqmax(ji)) / zdiagbis(ji,numeqmax(ji)) |
---|
[8422] | 565 | END DO |
---|
| 566 | |
---|
| 567 | DO numeq = nlay_i + nlay_s, nlay_s + 2, -1 |
---|
[8522] | 568 | DO ji = 1, nidx |
---|
[8422] | 569 | jk = numeq - nlay_s - 1 |
---|
| 570 | t_i_1d(ji,jk) = ( zindtbis(ji,numeq) - ztrid(ji,numeq,3) * t_i_1d(ji,jk+1) ) / zdiagbis(ji,numeq) |
---|
| 571 | END DO |
---|
| 572 | END DO |
---|
| 573 | |
---|
[8522] | 574 | DO ji = 1, nidx |
---|
[8422] | 575 | ! snow temperatures |
---|
[8522] | 576 | IF( ht_s_1d(ji) > 0._wp ) THEN |
---|
| 577 | t_s_1d(ji,nlay_s) = ( zindtbis(ji,nlay_s+1) - ztrid(ji,nlay_s+1,3) * t_i_1d(ji,1) ) & |
---|
| 578 | & / zdiagbis(ji,nlay_s+1) |
---|
| 579 | ENDIF |
---|
[8422] | 580 | ! surface temperature |
---|
[8518] | 581 | ztsub(ji) = t_su_1d(ji) |
---|
[8522] | 582 | IF( t_su_1d(ji) < rt0 ) THEN |
---|
[8422] | 583 | t_su_1d(ji) = ( zindtbis(ji,numeqmin(ji)) - ztrid(ji,numeqmin(ji),3) * & |
---|
[8522] | 584 | & ( isnow(ji) * t_s_1d(ji,1) + ( 1._wp - isnow(ji) ) * t_i_1d(ji,1) ) ) / zdiagbis(ji,numeqmin(ji)) |
---|
| 585 | ENDIF |
---|
[8422] | 586 | END DO |
---|
| 587 | ! |
---|
| 588 | !-------------------------------------------------------------------------- |
---|
| 589 | ! 11) Has the scheme converged ?, end of the iterative procedure | |
---|
| 590 | !-------------------------------------------------------------------------- |
---|
| 591 | ! |
---|
| 592 | ! check that nowhere it has started to melt |
---|
[8522] | 593 | ! zdti_max is a measure of error, it has to be under zdti_bnd |
---|
| 594 | zdti_max = 0._wp |
---|
| 595 | DO ji = 1, nidx |
---|
| 596 | t_su_1d(ji) = MAX( MIN( t_su_1d(ji) , rt0 ) , rt0 - 100._wp ) |
---|
| 597 | zdti_max = MAX( zdti_max, ABS( t_su_1d(ji) - ztsub(ji) ) ) |
---|
[8422] | 598 | END DO |
---|
| 599 | |
---|
| 600 | DO jk = 1, nlay_s |
---|
[8522] | 601 | DO ji = 1, nidx |
---|
| 602 | t_s_1d(ji,jk) = MAX( MIN( t_s_1d(ji,jk), rt0 ), rt0 - 100._wp ) |
---|
| 603 | zdti_max = MAX( zdti_max, ABS( t_s_1d(ji,jk) - ztsb(ji,jk) ) ) |
---|
[8422] | 604 | END DO |
---|
| 605 | END DO |
---|
| 606 | |
---|
| 607 | DO jk = 1, nlay_i |
---|
[8522] | 608 | DO ji = 1, nidx |
---|
[8422] | 609 | ztmelt_i = -tmut * s_i_1d(ji,jk) + rt0 |
---|
[8522] | 610 | t_i_1d(ji,jk) = MAX( MIN( t_i_1d(ji,jk), ztmelt_i ), rt0 - 100._wp ) |
---|
| 611 | zdti_max = MAX( zdti_max, ABS( t_i_1d(ji,jk) - ztib(ji,jk) ) ) |
---|
[8422] | 612 | END DO |
---|
| 613 | END DO |
---|
| 614 | |
---|
| 615 | ! Compute spatial maximum over all errors |
---|
| 616 | ! note that this could be optimized substantially by iterating only the non-converging points |
---|
| 617 | IF( lk_mpp ) CALL mpp_max( zdti_max, kcom=ncomm_ice ) |
---|
| 618 | |
---|
| 619 | END DO ! End of the do while iterative procedure |
---|
| 620 | |
---|
[8514] | 621 | IF( ln_icectl .AND. lwp ) THEN |
---|
[8422] | 622 | WRITE(numout,*) ' zdti_max : ', zdti_max |
---|
| 623 | WRITE(numout,*) ' iconv : ', iconv |
---|
| 624 | ENDIF |
---|
| 625 | |
---|
| 626 | ! |
---|
| 627 | !-------------------------------------------------------------------------! |
---|
| 628 | ! 12) Fluxes at the interfaces ! |
---|
| 629 | !-------------------------------------------------------------------------! |
---|
| 630 | DO ji = 1, nidx |
---|
| 631 | ! ! surface ice conduction flux |
---|
| 632 | fc_su(ji) = - isnow(ji) * zkappa_s(ji,0) * zg1s * (t_s_1d(ji,1) - t_su_1d(ji)) & |
---|
| 633 | & - ( 1._wp - isnow(ji) ) * zkappa_i(ji,0) * zg1 * (t_i_1d(ji,1) - t_su_1d(ji)) |
---|
| 634 | ! ! bottom ice conduction flux |
---|
| 635 | fc_bo_i(ji) = - zkappa_i(ji,nlay_i) * ( zg1*(t_bo_1d(ji) - t_i_1d(ji,nlay_i)) ) |
---|
| 636 | END DO |
---|
| 637 | |
---|
| 638 | ! --- computes sea ice energy of melting compulsory for icethd_dh --- ! |
---|
| 639 | CALL ice_thd_enmelt |
---|
| 640 | |
---|
| 641 | ! --- diagnose the change in non-solar flux due to surface temperature change --- ! |
---|
[8514] | 642 | IF ( ln_dqns_i ) THEN |
---|
[8422] | 643 | DO ji = 1, nidx |
---|
| 644 | hfx_err_dif_1d(ji) = hfx_err_dif_1d(ji) - ( qns_ice_1d(ji) - zqns_ice_b(ji) ) * a_i_1d(ji) |
---|
| 645 | END DO |
---|
| 646 | END IF |
---|
| 647 | |
---|
| 648 | ! --- diag conservation imbalance on heat diffusion - PART 2 --- ! |
---|
[8518] | 649 | ! hfx_dif = Heat flux used to warm/cool ice in W.m-2 |
---|
| 650 | ! zhfx_err = correction on the diagnosed heat flux due to non-convergence of the algorithm used to solve heat equation |
---|
[8422] | 651 | DO ji = 1, nidx |
---|
[8518] | 652 | zdq = - zq_ini(ji) + ( SUM( e_i_1d(ji,1:nlay_i) ) * ht_i_1d(ji) * r1_nlay_i + & |
---|
| 653 | & SUM( e_s_1d(ji,1:nlay_s) ) * ht_s_1d(ji) * r1_nlay_s ) |
---|
| 654 | |
---|
[8422] | 655 | IF( t_su_1d(ji) < rt0 ) THEN ! case T_su < 0degC |
---|
[8518] | 656 | zhfx_err = ( qns_ice_1d(ji) + qsr_ice_1d(ji) - zradtr_i(ji,nlay_i) - fc_bo_i(ji) + zdq * r1_rdtice ) * a_i_1d(ji) |
---|
[8422] | 657 | ELSE ! case T_su = 0degC |
---|
[8518] | 658 | zhfx_err = ( fc_su(ji) + i0(ji) * qsr_ice_1d(ji) - zradtr_i(ji,nlay_i) - fc_bo_i(ji) + zdq * r1_rdtice ) * a_i_1d(ji) |
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[8422] | 659 | ENDIF |
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[8518] | 660 | hfx_dif_1d(ji) = hfx_dif_1d(ji) - zdq * r1_rdtice * a_i_1d(ji) |
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[8422] | 661 | |
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| 662 | ! total heat that is sent to the ocean (i.e. not used in the heat diffusion equation) |
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[8518] | 663 | hfx_err_dif_1d(ji) = hfx_err_dif_1d(ji) + zhfx_err |
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[8422] | 664 | |
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| 665 | END DO |
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[8522] | 666 | |
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| 667 | ! --- Diagnostics SIMIP --- ! |
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| 668 | DO ji = 1, nidx |
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| 669 | !--- Conduction fluxes (positive downwards) |
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| 670 | diag_fc_bo_1d(ji) = diag_fc_bo_1d(ji) + fc_bo_i(ji) * a_i_1d(ji) / at_i_1d(ji) |
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| 671 | diag_fc_su_1d(ji) = diag_fc_su_1d(ji) + fc_su(ji) * a_i_1d(ji) / at_i_1d(ji) |
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| 672 | |
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| 673 | !--- Snow-ice interfacial temperature (diagnostic SIMIP) |
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| 674 | zfac = rn_cnd_s * zh_i(ji) + ztcond_i(ji,1) * zh_s(ji) |
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| 675 | IF( zh_s(ji) >= 1.e-3 .AND. zfac > epsi10 ) THEN |
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| 676 | t_si_1d(ji) = ( rn_cnd_s * zh_i(ji) * t_s_1d(ji,1) + & |
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| 677 | & ztcond_i(ji,1) * zh_s(ji) * t_i_1d(ji,1) ) / zfac |
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| 678 | ELSE |
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| 679 | t_si_1d(ji) = t_su_1d(ji) |
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| 680 | ENDIF |
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| 681 | END DO |
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[8422] | 682 | ! |
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| 683 | END SUBROUTINE ice_thd_dif |
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| 684 | |
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[8486] | 685 | |
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[8422] | 686 | SUBROUTINE ice_thd_enmelt |
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| 687 | !!----------------------------------------------------------------------- |
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| 688 | !! *** ROUTINE ice_thd_enmelt *** |
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| 689 | !! |
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| 690 | !! ** Purpose : Computes sea ice energy of melting q_i (J.m-3) from temperature |
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| 691 | !! |
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| 692 | !! ** Method : Formula (Bitz and Lipscomb, 1999) |
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| 693 | !!------------------------------------------------------------------- |
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| 694 | INTEGER :: ji, jk ! dummy loop indices |
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| 695 | REAL(wp) :: ztmelts ! local scalar |
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| 696 | !!------------------------------------------------------------------- |
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| 697 | ! |
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| 698 | DO jk = 1, nlay_i ! Sea ice energy of melting |
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| 699 | DO ji = 1, nidx |
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[8522] | 700 | ztmelts = - tmut * s_i_1d(ji,jk) |
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| 701 | t_i_1d(ji,jk) = MIN( t_i_1d(ji,jk), ztmelts + rt0 ) ! Force t_i_1d to be lower than melting point |
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| 702 | ! (sometimes dif scheme produces abnormally high temperatures) |
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| 703 | e_i_1d(ji,jk) = rhoic * ( cpic * ( ztmelts - ( t_i_1d(ji,jk) - rt0 ) ) & |
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| 704 | & + lfus * ( 1._wp - ztmelts / ( t_i_1d(ji,jk) - rt0 ) ) & |
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| 705 | & - rcp * ztmelts ) |
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[8422] | 706 | END DO |
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| 707 | END DO |
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| 708 | DO jk = 1, nlay_s ! Snow energy of melting |
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| 709 | DO ji = 1, nidx |
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| 710 | e_s_1d(ji,jk) = rhosn * ( cpic * ( rt0 - t_s_1d(ji,jk) ) + lfus ) |
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| 711 | END DO |
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| 712 | END DO |
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| 713 | ! |
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| 714 | END SUBROUTINE ice_thd_enmelt |
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| 715 | |
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| 716 | #else |
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| 717 | !!---------------------------------------------------------------------- |
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| 718 | !! Dummy Module No LIM-3 sea-ice model |
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| 719 | !!---------------------------------------------------------------------- |
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| 720 | #endif |
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[8486] | 721 | |
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[8422] | 722 | !!====================================================================== |
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| 723 | END MODULE icethd_dif |
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