| 1 | MODULE limrhg |
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| 2 | !!====================================================================== |
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| 3 | !! *** MODULE limrhg *** |
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| 4 | !! Ice rheology : sea ice rheology |
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| 5 | !!====================================================================== |
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| 6 | !! History : - ! 2007-03 (M.A. Morales Maqueda, S. Bouillon) Original code |
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| 7 | !! 3.0 ! 2008-03 (M. Vancoppenolle) LIM3 |
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| 8 | !! - ! 2008-11 (M. Vancoppenolle, S. Bouillon, Y. Aksenov) add surface tilt in ice rheolohy |
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| 9 | !! 3.3 ! 2009-05 (G.Garric) addition of the lim2_evp cas |
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| 10 | !! 3.4 ! 2011-01 (A. Porter) dynamical allocation |
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| 11 | !! 3.5 ! 2012-08 (R. Benshila) AGRIF |
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| 12 | !!---------------------------------------------------------------------- |
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| 13 | #if defined key_lim3 || ( defined key_lim2 && ! defined key_lim2_vp ) |
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| 14 | !!---------------------------------------------------------------------- |
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| 15 | !! 'key_lim3' OR LIM-3 sea-ice model |
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| 16 | !! 'key_lim2' AND NOT 'key_lim2_vp' EVP LIM-2 sea-ice model |
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| 17 | !!---------------------------------------------------------------------- |
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| 18 | !! lim_rhg : computes ice velocities |
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| 19 | !!---------------------------------------------------------------------- |
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| 20 | USE phycst ! Physical constant |
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| 21 | USE oce , ONLY : snwice_mass, snwice_mass_b |
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| 22 | USE par_oce ! Ocean parameters |
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| 23 | USE dom_oce ! Ocean domain |
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| 24 | USE sbc_oce ! Surface boundary condition: ocean fields |
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| 25 | USE sbc_ice ! Surface boundary condition: ice fields |
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| 26 | #if defined key_lim3 |
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| 27 | USE ice ! LIM-3: ice variables |
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| 28 | USE dom_ice ! LIM-3: ice domain |
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| 29 | USE limitd_me ! LIM-3: |
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| 30 | #else |
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| 31 | USE ice_2 ! LIM-2: ice variables |
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| 32 | USE dom_ice_2 ! LIM-2: ice domain |
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| 33 | #endif |
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| 34 | USE lbclnk ! Lateral Boundary Condition / MPP link |
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| 35 | USE lib_mpp ! MPP library |
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| 36 | USE in_out_manager ! I/O manager |
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| 37 | USE prtctl ! Print control |
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| 38 | USE lib_fortran ! Fortran utilities (allows no signed zero when 'key_nosignedzero' defined) |
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| 39 | #if defined key_agrif && defined key_lim2 |
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| 40 | USE agrif_lim2_interp |
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| 41 | #endif |
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| 42 | #if defined key_bdy |
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| 43 | USE bdyice_lim |
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| 44 | #endif |
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| 45 | |
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| 46 | IMPLICIT NONE |
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| 47 | PRIVATE |
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| 48 | |
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| 49 | PUBLIC lim_rhg ! routine called by lim_dyn (or lim_dyn_2) |
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| 50 | |
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| 51 | !! * Substitutions |
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| 52 | # include "vectopt_loop_substitute.h90" |
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| 53 | !!---------------------------------------------------------------------- |
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| 54 | !! NEMO/LIM3 4.0 , UCL - NEMO Consortium (2011) |
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| 55 | !! $Id: limrhg.F90 5888 2015-11-13 16:47:32Z clem $ |
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| 56 | !! Software governed by the CeCILL licence (NEMOGCM/NEMO_CeCILL.txt) |
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| 57 | !!---------------------------------------------------------------------- |
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| 58 | CONTAINS |
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| 59 | |
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| 60 | SUBROUTINE lim_rhg( k_j1, k_jpj ) |
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| 61 | !!------------------------------------------------------------------- |
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| 62 | !! *** SUBROUTINE lim_rhg *** |
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| 63 | !! EVP-C-grid |
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| 64 | !! |
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| 65 | !! ** purpose : determines sea ice drift from wind stress, ice-ocean |
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| 66 | !! stress and sea-surface slope. Ice-ice interaction is described by |
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| 67 | !! a non-linear elasto-viscous-plastic (EVP) law including shear |
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| 68 | !! strength and a bulk rheology (Hunke and Dukowicz, 2002). |
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| 69 | !! |
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| 70 | !! The points in the C-grid look like this, dear reader |
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| 71 | !! |
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| 72 | !! (ji,jj) |
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| 73 | !! | |
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| 74 | !! | |
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| 75 | !! (ji-1,jj) | (ji,jj) |
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| 76 | !! --------- |
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| 77 | !! | | |
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| 78 | !! | (ji,jj) |------(ji,jj) |
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| 79 | !! | | |
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| 80 | !! --------- |
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| 81 | !! (ji-1,jj-1) (ji,jj-1) |
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| 82 | !! |
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| 83 | !! ** Inputs : - wind forcing (stress), oceanic currents |
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| 84 | !! ice total volume (vt_i) per unit area |
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| 85 | !! snow total volume (vt_s) per unit area |
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| 86 | !! |
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| 87 | !! ** Action : - compute u_ice, v_ice : the components of the |
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| 88 | !! sea-ice velocity vector |
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| 89 | !! - compute delta_i, shear_i, divu_i, which are inputs |
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| 90 | !! of the ice thickness distribution |
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| 91 | !! |
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| 92 | !! ** Steps : 1) Compute ice snow mass, ice strength |
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| 93 | !! 2) Compute wind, oceanic stresses, mass terms and |
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| 94 | !! coriolis terms of the momentum equation |
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| 95 | !! 3) Solve the momentum equation (iterative procedure) |
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| 96 | !! 4) Prevent high velocities if the ice is thin |
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| 97 | !! 5) Recompute invariants of the strain rate tensor |
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| 98 | !! which are inputs of the ITD, store stress |
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| 99 | !! for the next time step |
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| 100 | !! 6) Control prints of residual (convergence) |
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| 101 | !! and charge ellipse. |
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| 102 | !! The user should make sure that the parameters |
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| 103 | !! nn_nevp, elastic time scale and rn_creepl maintain stress state |
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| 104 | !! on the charge ellipse for plastic flow |
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| 105 | !! e.g. in the Canadian Archipelago |
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| 106 | !! |
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| 107 | !! References : Hunke and Dukowicz, JPO97 |
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| 108 | !! Bouillon et al., Ocean Modelling 2009 |
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| 109 | !!------------------------------------------------------------------- |
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| 110 | INTEGER, INTENT(in) :: k_j1 ! southern j-index for ice computation |
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| 111 | INTEGER, INTENT(in) :: k_jpj ! northern j-index for ice computation |
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| 112 | !! |
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| 113 | INTEGER :: ji, jj ! dummy loop indices |
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| 114 | INTEGER :: jter ! local integers |
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| 115 | CHARACTER (len=50) :: charout |
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| 116 | REAL(wp) :: zt11, zt12, zt21, zt22, ztagnx, ztagny, delta ! |
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| 117 | REAL(wp) :: za, zstms ! local scalars |
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| 118 | REAL(wp) :: zc1, zc2, zc3 ! ice mass |
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| 119 | |
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| 120 | REAL(wp) :: dtevp , z1_dtevp ! time step for subcycling |
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| 121 | REAL(wp) :: dtotel, z1_dtotel, ecc2, ecci ! square of yield ellipse eccenticity |
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| 122 | REAL(wp) :: z0, zr, zcca, zccb ! temporary scalars |
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| 123 | REAL(wp) :: zu_ice2, zv_ice1 ! |
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| 124 | REAL(wp) :: zddc, zdtc ! delta on corners and on centre |
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| 125 | REAL(wp) :: zdst ! shear at the center of the grid point |
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| 126 | REAL(wp) :: zdsshx, zdsshy ! term for the gradient of ocean surface |
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| 127 | REAL(wp) :: sigma1, sigma2 ! internal ice stress |
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| 128 | |
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| 129 | REAL(wp) :: zresm ! Maximal error on ice velocity |
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| 130 | REAL(wp) :: zintb, zintn ! dummy argument |
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| 131 | |
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| 132 | REAL(wp), DIMENSION(jpi,jpj) :: zpresh ! temporary array for ice strength |
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| 133 | REAL(wp), DIMENSION(jpi,jpj) :: zpreshc ! Ice strength on grid cell corners (zpreshc) |
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| 134 | REAL(wp), DIMENSION(jpi,jpj) :: zfrld1, zfrld2 ! lead fraction on U/V points |
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| 135 | REAL(wp), DIMENSION(jpi,jpj) :: zmass1, zmass2 ! ice/snow mass on U/V points |
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| 136 | REAL(wp), DIMENSION(jpi,jpj) :: zcorl1, zcorl2 ! coriolis parameter on U/V points |
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| 137 | REAL(wp), DIMENSION(jpi,jpj) :: za1ct , za2ct ! temporary arrays |
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| 138 | REAL(wp), DIMENSION(jpi,jpj) :: v_oce1 ! ocean u/v component on U points |
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| 139 | REAL(wp), DIMENSION(jpi,jpj) :: u_oce2 ! ocean u/v component on V points |
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| 140 | REAL(wp), DIMENSION(jpi,jpj) :: u_ice2, v_ice1 ! ice u/v component on V/U point |
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| 141 | REAL(wp), DIMENSION(jpi,jpj) :: zf1 , zf2 ! arrays for internal stresses |
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| 142 | REAL(wp), DIMENSION(jpi,jpj) :: zmask ! mask ocean grid points |
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| 143 | |
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| 144 | REAL(wp), DIMENSION(jpi,jpj) :: zdt ! tension at centre of grid cells |
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| 145 | REAL(wp), DIMENSION(jpi,jpj) :: zds ! Shear on northeast corner of grid cells |
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| 146 | REAL(wp), DIMENSION(jpi,jpj) :: zs1 , zs2 ! Diagonal stress tensor components zs1 and zs2 |
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| 147 | REAL(wp), DIMENSION(jpi,jpj) :: zs12 ! Non-diagonal stress tensor component zs12 |
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| 148 | REAL(wp), DIMENSION(jpi,jpj) :: zu_ice, zv_ice, zresr ! Local error on velocity |
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| 149 | REAL(wp), DIMENSION(jpi,jpj) :: zpice ! array used for the calculation of ice surface slope: |
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| 150 | ! ocean surface (ssh_m) if ice is not embedded |
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| 151 | ! ice top surface if ice is embedded |
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| 152 | |
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| 153 | REAL(wp), PARAMETER :: zepsi = 1.0e-20_wp ! tolerance parameter |
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| 154 | REAL(wp), PARAMETER :: zvmin = 1.0e-03_wp ! ice volume below which ice velocity equals ocean velocity |
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| 155 | !!------------------------------------------------------------------- |
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| 156 | |
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| 157 | |
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| 158 | #if defined key_lim2 && ! defined key_lim2_vp |
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| 159 | # if defined key_agrif |
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| 160 | USE ice_2, vt_s => hsnm |
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| 161 | USE ice_2, vt_i => hicm |
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| 162 | # else |
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| 163 | vt_s => hsnm |
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| 164 | vt_i => hicm |
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| 165 | # endif |
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| 166 | at_i(:,:) = 1. - frld(:,:) |
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| 167 | #endif |
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| 168 | #if defined key_agrif && defined key_lim2 |
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| 169 | CALL agrif_rhg_lim2_load ! First interpolation of coarse values |
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| 170 | #endif |
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| 171 | ! |
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| 172 | !------------------------------------------------------------------------------! |
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| 173 | ! 1) Ice strength (zpresh) ! |
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| 174 | !------------------------------------------------------------------------------! |
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| 175 | ! |
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| 176 | ! Put every vector to 0 |
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| 177 | delta_i(:,:) = 0._wp ; |
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| 178 | zpresh (:,:) = 0._wp ; |
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| 179 | zpreshc(:,:) = 0._wp |
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| 180 | u_ice2 (:,:) = 0._wp ; v_ice1(:,:) = 0._wp |
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| 181 | divu_i (:,:) = 0._wp ; zdt (:,:) = 0._wp ; zds(:,:) = 0._wp |
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| 182 | shear_i(:,:) = 0._wp |
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| 183 | |
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| 184 | #if defined key_lim3 |
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| 185 | CALL lim_itd_me_icestrength( nn_icestr ) ! LIM-3: Ice strength on T-points |
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| 186 | #endif |
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| 187 | |
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| 188 | DO jj = k_j1 , k_jpj ! Ice mass and temp variables |
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| 189 | DO ji = 1 , jpi |
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| 190 | #if defined key_lim3 |
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| 191 | zpresh(ji,jj) = tmask(ji,jj,1) * strength(ji,jj) |
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| 192 | #endif |
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| 193 | #if defined key_lim2 |
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| 194 | zpresh(ji,jj) = tmask(ji,jj,1) * pstar * vt_i(ji,jj) * EXP( -c_rhg * (1. - at_i(ji,jj) ) ) |
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| 195 | #endif |
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| 196 | ! zmask = 1 where there is ice or on land |
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| 197 | zmask(ji,jj) = 1._wp - ( 1._wp - MAX( 0._wp , SIGN ( 1._wp , vt_i(ji,jj) - zepsi ) ) ) * tmask(ji,jj,1) |
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| 198 | END DO |
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| 199 | END DO |
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| 200 | |
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| 201 | ! Ice strength on grid cell corners (zpreshc) |
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| 202 | ! needed for calculation of shear stress |
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| 203 | DO jj = k_j1+1, k_jpj-1 |
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| 204 | DO ji = 2, jpim1 !RB caution no fs_ (ji+1,jj+1) |
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| 205 | zstms = tmask(ji+1,jj+1,1) * wght(ji+1,jj+1,2,2) + tmask(ji,jj+1,1) * wght(ji+1,jj+1,1,2) + & |
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| 206 | & tmask(ji+1,jj,1) * wght(ji+1,jj+1,2,1) + tmask(ji,jj,1) * wght(ji+1,jj+1,1,1) |
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| 207 | zpreshc(ji,jj) = ( zpresh(ji+1,jj+1) * wght(ji+1,jj+1,2,2) + zpresh(ji,jj+1) * wght(ji+1,jj+1,1,2) + & |
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| 208 | & zpresh(ji+1,jj) * wght(ji+1,jj+1,2,1) + zpresh(ji,jj) * wght(ji+1,jj+1,1,1) & |
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| 209 | & ) / MAX( zstms, zepsi ) |
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| 210 | END DO |
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| 211 | END DO |
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| 212 | CALL lbc_lnk( zpreshc(:,:), 'F', 1. ) |
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| 213 | ! |
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| 214 | !------------------------------------------------------------------------------! |
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| 215 | ! 2) Wind / ocean stress, mass terms, coriolis terms |
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| 216 | !------------------------------------------------------------------------------! |
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| 217 | ! |
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| 218 | ! Wind stress, coriolis and mass terms on the sides of the squares |
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| 219 | ! zfrld1: lead fraction on U-points |
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| 220 | ! zfrld2: lead fraction on V-points |
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| 221 | ! zmass1: ice/snow mass on U-points |
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| 222 | ! zmass2: ice/snow mass on V-points |
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| 223 | ! zcorl1: Coriolis parameter on U-points |
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| 224 | ! zcorl2: Coriolis parameter on V-points |
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| 225 | ! (ztagnx,ztagny): wind stress on U/V points |
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| 226 | ! v_oce1: ocean v component on u points |
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| 227 | ! u_oce2: ocean u component on v points |
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| 228 | |
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| 229 | IF( nn_ice_embd == 2 ) THEN !== embedded sea ice: compute representative ice top surface ==! |
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| 230 | ! |
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| 231 | ! average interpolation coeff as used in dynspg = (1/nn_fsbc) * {SUM[n/nn_fsbc], n=0,nn_fsbc-1} |
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| 232 | ! = (1/nn_fsbc)^2 * {SUM[n], n=0,nn_fsbc-1} |
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| 233 | zintn = REAL( nn_fsbc - 1 ) / REAL( nn_fsbc ) * 0.5_wp |
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| 234 | ! |
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| 235 | ! average interpolation coeff as used in dynspg = (1/nn_fsbc) * {SUM[1-n/nn_fsbc], n=0,nn_fsbc-1} |
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| 236 | ! = (1/nn_fsbc)^2 * (nn_fsbc^2 - {SUM[n], n=0,nn_fsbc-1}) |
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| 237 | zintb = REAL( nn_fsbc + 1 ) / REAL( nn_fsbc ) * 0.5_wp |
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| 238 | ! |
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| 239 | zpice(:,:) = ssh_m(:,:) + ( zintn * snwice_mass(:,:) + zintb * snwice_mass_b(:,:) ) * r1_rau0 |
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| 240 | ! |
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| 241 | ELSE !== non-embedded sea ice: use ocean surface for slope calculation ==! |
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| 242 | zpice(:,:) = ssh_m(:,:) |
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| 243 | ENDIF |
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| 244 | |
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| 245 | DO jj = k_j1+1, k_jpj-1 |
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| 246 | DO ji = fs_2, fs_jpim1 |
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| 247 | |
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| 248 | zc1 = tmask(ji ,jj ,1) * ( rhosn * vt_s(ji ,jj ) + rhoic * vt_i(ji ,jj ) ) |
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| 249 | zc2 = tmask(ji+1,jj ,1) * ( rhosn * vt_s(ji+1,jj ) + rhoic * vt_i(ji+1,jj ) ) |
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| 250 | zc3 = tmask(ji ,jj+1,1) * ( rhosn * vt_s(ji ,jj+1) + rhoic * vt_i(ji ,jj+1) ) |
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| 251 | |
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| 252 | zt11 = tmask(ji ,jj,1) * e1t(ji ,jj) |
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| 253 | zt12 = tmask(ji+1,jj,1) * e1t(ji+1,jj) |
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| 254 | zt21 = tmask(ji,jj ,1) * e2t(ji,jj ) |
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| 255 | zt22 = tmask(ji,jj+1,1) * e2t(ji,jj+1) |
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| 256 | |
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| 257 | ! Leads area. |
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| 258 | zfrld1(ji,jj) = ( zt12 * ( 1.0 - at_i(ji,jj) ) + zt11 * ( 1.0 - at_i(ji+1,jj) ) ) / ( zt11 + zt12 + zepsi ) |
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| 259 | zfrld2(ji,jj) = ( zt22 * ( 1.0 - at_i(ji,jj) ) + zt21 * ( 1.0 - at_i(ji,jj+1) ) ) / ( zt21 + zt22 + zepsi ) |
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| 260 | |
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| 261 | ! Mass, coriolis coeff. and currents |
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| 262 | zmass1(ji,jj) = ( zt12 * zc1 + zt11 * zc2 ) / ( zt11 + zt12 + zepsi ) |
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| 263 | zmass2(ji,jj) = ( zt22 * zc1 + zt21 * zc3 ) / ( zt21 + zt22 + zepsi ) |
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| 264 | zcorl1(ji,jj) = zmass1(ji,jj) * ( e1t(ji+1,jj) * ff_f(ji,jj) + e1t(ji,jj) * ff_f(ji+1,jj) ) & |
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| 265 | & / ( e1t(ji,jj) + e1t(ji+1,jj) + zepsi ) |
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| 266 | zcorl2(ji,jj) = zmass2(ji,jj) * ( e2t(ji,jj+1) * ff_f(ji,jj) + e2t(ji,jj) * ff_f(ji,jj+1) ) & |
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| 267 | & / ( e2t(ji,jj+1) + e2t(ji,jj) + zepsi ) |
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| 268 | ! |
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| 269 | ! Ocean has no slip boundary condition |
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| 270 | v_oce1(ji,jj) = 0.5 * ( ( v_oce(ji ,jj) + v_oce(ji ,jj-1) ) * e1t(ji,jj) & |
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| 271 | & + ( v_oce(ji+1,jj) + v_oce(ji+1,jj-1) ) * e1t(ji+1,jj) ) & |
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| 272 | & / ( e1t(ji+1,jj) + e1t(ji,jj) ) * umask(ji,jj,1) |
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| 273 | |
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| 274 | u_oce2(ji,jj) = 0.5 * ( ( u_oce(ji,jj ) + u_oce(ji-1,jj ) ) * e2t(ji,jj) & |
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| 275 | & + ( u_oce(ji,jj+1) + u_oce(ji-1,jj+1) ) * e2t(ji,jj+1) ) & |
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| 276 | & / ( e2t(ji,jj+1) + e2t(ji,jj) ) * vmask(ji,jj,1) |
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| 277 | |
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| 278 | ! Wind stress at U,V-point |
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| 279 | ztagnx = ( 1. - zfrld1(ji,jj) ) * utau_ice(ji,jj) |
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| 280 | ztagny = ( 1. - zfrld2(ji,jj) ) * vtau_ice(ji,jj) |
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| 281 | |
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| 282 | ! Computation of the velocity field taking into account the ice internal interaction. |
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| 283 | ! Terms that are independent of the velocity field. |
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| 284 | |
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| 285 | ! SB On utilise maintenant le gradient de la pente de l'ocean |
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| 286 | ! include it later |
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| 287 | |
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| 288 | zdsshx = ( zpice(ji+1,jj) - zpice(ji,jj) ) * r1_e1u(ji,jj) |
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| 289 | zdsshy = ( zpice(ji,jj+1) - zpice(ji,jj) ) * r1_e2v(ji,jj) |
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| 290 | |
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| 291 | za1ct(ji,jj) = ztagnx - zmass1(ji,jj) * grav * zdsshx |
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| 292 | za2ct(ji,jj) = ztagny - zmass2(ji,jj) * grav * zdsshy |
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| 293 | |
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| 294 | END DO |
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| 295 | END DO |
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| 296 | |
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| 297 | ! |
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| 298 | !------------------------------------------------------------------------------! |
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| 299 | ! 3) Solution of the momentum equation, iterative procedure |
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| 300 | !------------------------------------------------------------------------------! |
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| 301 | ! |
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| 302 | ! Time step for subcycling |
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| 303 | dtevp = rdt_ice / nn_nevp |
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| 304 | #if defined key_lim3 |
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| 305 | dtotel = dtevp / ( 2._wp * rn_relast * rdt_ice ) |
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| 306 | #else |
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| 307 | dtotel = dtevp / ( 2._wp * telast ) |
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| 308 | #endif |
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| 309 | z1_dtotel = 1._wp / ( 1._wp + dtotel ) |
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| 310 | z1_dtevp = 1._wp / dtevp |
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| 311 | !-ecc2: square of yield ellipse eccenticrity (reminder: must become a namelist parameter) |
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| 312 | ecc2 = rn_ecc * rn_ecc |
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| 313 | ecci = 1. / ecc2 |
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| 314 | |
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| 315 | !-Initialise stress tensor |
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| 316 | zs1 (:,:) = stress1_i (:,:) |
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| 317 | zs2 (:,:) = stress2_i (:,:) |
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| 318 | zs12(:,:) = stress12_i(:,:) |
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| 319 | |
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| 320 | ! !----------------------! |
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| 321 | DO jter = 1 , nn_nevp ! loop over jter ! |
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| 322 | ! !----------------------! |
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| 323 | DO jj = k_j1, k_jpj-1 |
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| 324 | zu_ice(:,jj) = u_ice(:,jj) ! velocity at previous time step |
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| 325 | zv_ice(:,jj) = v_ice(:,jj) |
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| 326 | END DO |
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| 327 | |
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| 328 | DO jj = k_j1+1, k_jpj-1 |
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| 329 | DO ji = fs_2, fs_jpim1 !RB bug no vect opt due to zmask |
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| 330 | |
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| 331 | ! |
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| 332 | !- Divergence, tension and shear (Section a. Appendix B of Hunke & Dukowicz, 2002) |
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| 333 | !- divu_i(:,:), zdt(:,:): divergence and tension at centre of grid cells |
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| 334 | !- zds(:,:): shear on northeast corner of grid cells |
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| 335 | ! |
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| 336 | !- IMPORTANT REMINDER: Dear Gurvan, note that, the way these terms are coded, |
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| 337 | ! there are many repeated calculations. |
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| 338 | ! Speed could be improved by regrouping terms. For |
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| 339 | ! the moment, however, the stress is on clarity of coding to avoid |
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| 340 | ! bugs (Martin, for Miguel). |
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| 341 | ! |
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| 342 | !- ALSO: arrays zdt, zds and delta could |
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| 343 | ! be removed in the future to minimise memory demand. |
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| 344 | ! |
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| 345 | !- MORE NOTES: Note that we are calculating deformation rates and stresses on the corners of |
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| 346 | ! grid cells, exactly as in the B grid case. For simplicity, the indexation on |
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| 347 | ! the corners is the same as in the B grid. |
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| 348 | ! |
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| 349 | ! |
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| 350 | divu_i(ji,jj) = ( e2u(ji,jj) * u_ice(ji,jj) - e2u(ji-1,jj) * u_ice(ji-1,jj) & |
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| 351 | & + e1v(ji,jj) * v_ice(ji,jj) - e1v(ji,jj-1) * v_ice(ji,jj-1) & |
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| 352 | & ) * r1_e1e2t(ji,jj) |
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| 353 | |
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| 354 | zdt(ji,jj) = ( ( u_ice(ji,jj) * r1_e2u(ji,jj) - u_ice(ji-1,jj) * r1_e2u(ji-1,jj) ) * e2t(ji,jj) * e2t(ji,jj) & |
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| 355 | & - ( v_ice(ji,jj) * r1_e1v(ji,jj) - v_ice(ji,jj-1) * r1_e1v(ji,jj-1) ) * e1t(ji,jj) * e1t(ji,jj) & |
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| 356 | & ) * r1_e1e2t(ji,jj) |
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| 357 | |
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| 358 | ! |
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| 359 | zds(ji,jj) = ( ( u_ice(ji,jj+1) * r1_e1u(ji,jj+1) - u_ice(ji,jj) * r1_e1u(ji,jj) ) * e1f(ji,jj) * e1f(ji,jj) & |
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| 360 | & + ( v_ice(ji+1,jj) * r1_e2v(ji+1,jj) - v_ice(ji,jj) * r1_e2v(ji,jj) ) * e2f(ji,jj) * e2f(ji,jj) & |
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| 361 | & ) * r1_e1e2f(ji,jj) * ( 2._wp - fmask(ji,jj,1) ) & |
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| 362 | & * zmask(ji,jj) * zmask(ji,jj+1) * zmask(ji+1,jj) * zmask(ji+1,jj+1) |
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| 363 | |
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| 364 | |
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| 365 | v_ice1(ji,jj) = 0.5_wp * ( ( v_ice(ji ,jj) + v_ice(ji ,jj-1) ) * e1t(ji+1,jj) & |
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| 366 | & + ( v_ice(ji+1,jj) + v_ice(ji+1,jj-1) ) * e1t(ji ,jj) ) & |
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| 367 | & / ( e1t(ji+1,jj) + e1t(ji,jj) ) * umask(ji,jj,1) |
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| 368 | |
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| 369 | u_ice2(ji,jj) = 0.5_wp * ( ( u_ice(ji,jj ) + u_ice(ji-1,jj ) ) * e2t(ji,jj+1) & |
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| 370 | & + ( u_ice(ji,jj+1) + u_ice(ji-1,jj+1) ) * e2t(ji,jj ) ) & |
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| 371 | & / ( e2t(ji,jj+1) + e2t(ji,jj) ) * vmask(ji,jj,1) |
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| 372 | END DO |
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| 373 | END DO |
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| 374 | |
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| 375 | CALL lbc_lnk_multi( v_ice1, 'U', -1., u_ice2, 'V', -1. ) ! lateral boundary cond. |
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| 376 | |
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| 377 | DO jj = k_j1+1, k_jpj-1 |
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| 378 | DO ji = fs_2, fs_jpim1 |
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| 379 | |
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| 380 | !- Calculate Delta at centre of grid cells |
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| 381 | zdst = ( e2u(ji,jj) * v_ice1(ji,jj) - e2u(ji-1,jj ) * v_ice1(ji-1,jj ) & |
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| 382 | & + e1v(ji,jj) * u_ice2(ji,jj) - e1v(ji ,jj-1) * u_ice2(ji ,jj-1) & |
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| 383 | & ) * r1_e1e2t(ji,jj) |
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| 384 | |
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| 385 | delta = SQRT( divu_i(ji,jj)**2 + ( zdt(ji,jj)**2 + zdst**2 ) * usecc2 ) |
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| 386 | delta_i(ji,jj) = delta + rn_creepl |
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| 387 | |
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| 388 | !- Calculate Delta on corners |
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| 389 | zddc = ( ( v_ice1(ji,jj+1) * r1_e1u(ji,jj+1) - v_ice1(ji,jj) * r1_e1u(ji,jj) ) * e1f(ji,jj) * e1f(ji,jj) & |
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| 390 | & + ( u_ice2(ji+1,jj) * r1_e2v(ji+1,jj) - u_ice2(ji,jj) * r1_e2v(ji,jj) ) * e2f(ji,jj) * e2f(ji,jj) & |
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| 391 | & ) * r1_e1e2f(ji,jj) |
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| 392 | |
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| 393 | zdtc = (- ( v_ice1(ji,jj+1) * r1_e1u(ji,jj+1) - v_ice1(ji,jj) * r1_e1u(ji,jj) ) * e1f(ji,jj) * e1f(ji,jj) & |
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| 394 | & + ( u_ice2(ji+1,jj) * r1_e2v(ji+1,jj) - u_ice2(ji,jj) * r1_e2v(ji,jj) ) * e2f(ji,jj) * e2f(ji,jj) & |
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| 395 | & ) * r1_e1e2f(ji,jj) |
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| 396 | |
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| 397 | zddc = SQRT( zddc**2 + ( zdtc**2 + zds(ji,jj)**2 ) * usecc2 ) + rn_creepl |
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| 398 | |
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| 399 | !-Calculate stress tensor components zs1 and zs2 at centre of grid cells (see section 3.5 of CICE user's guide). |
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| 400 | zs1(ji,jj) = ( zs1 (ji,jj) + dtotel * ( divu_i(ji,jj) - delta ) / delta_i(ji,jj) * zpresh(ji,jj) & |
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| 401 | & ) * z1_dtotel |
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| 402 | zs2(ji,jj) = ( zs2 (ji,jj) + dtotel * ecci * zdt(ji,jj) / delta_i(ji,jj) * zpresh(ji,jj) & |
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| 403 | & ) * z1_dtotel |
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| 404 | !-Calculate stress tensor component zs12 at corners |
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| 405 | zs12(ji,jj) = ( zs12(ji,jj) + dtotel * ecci * zds(ji,jj) / ( 2._wp * zddc ) * zpreshc(ji,jj) & |
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| 406 | & ) * z1_dtotel |
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| 407 | |
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| 408 | END DO |
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| 409 | END DO |
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| 410 | |
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| 411 | CALL lbc_lnk_multi( zs1 , 'T', 1., zs2, 'T', 1., zs12, 'F', 1. ) |
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| 412 | |
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| 413 | ! Ice internal stresses (Appendix C of Hunke and Dukowicz, 2002) |
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| 414 | DO jj = k_j1+1, k_jpj-1 |
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| 415 | DO ji = fs_2, fs_jpim1 |
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| 416 | !- contribution of zs1, zs2 and zs12 to zf1 |
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| 417 | zf1(ji,jj) = 0.5 * ( ( zs1(ji+1,jj) - zs1(ji,jj) ) * e2u(ji,jj) & |
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| 418 | & + ( zs2(ji+1,jj) * e2t(ji+1,jj)**2 - zs2(ji,jj) * e2t(ji,jj)**2 ) * r1_e2u(ji,jj) & |
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| 419 | & + 2.0 * ( zs12(ji,jj) * e1f(ji,jj)**2 - zs12(ji,jj-1) * e1f(ji,jj-1)**2 ) * r1_e1u(ji,jj) & |
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| 420 | & ) * r1_e1e2u(ji,jj) |
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| 421 | ! contribution of zs1, zs2 and zs12 to zf2 |
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| 422 | zf2(ji,jj) = 0.5 * ( ( zs1(ji,jj+1) - zs1(ji,jj) ) * e1v(ji,jj) & |
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| 423 | & - ( zs2(ji,jj+1) * e1t(ji,jj+1)**2 - zs2(ji,jj) * e1t(ji,jj)**2 ) * r1_e1v(ji,jj) & |
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| 424 | & + 2.0 * ( zs12(ji,jj) * e2f(ji,jj)**2 - zs12(ji-1,jj) * e2f(ji-1,jj)**2 ) * r1_e2v(ji,jj) & |
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| 425 | & ) * r1_e1e2v(ji,jj) |
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| 426 | END DO |
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| 427 | END DO |
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| 428 | ! |
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| 429 | ! Computation of ice velocity |
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| 430 | ! |
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| 431 | ! Both the Coriolis term and the ice-ocean drag are solved semi-implicitly. |
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| 432 | ! |
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| 433 | IF (MOD(jter,2).eq.0) THEN |
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| 434 | |
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| 435 | DO jj = k_j1+1, k_jpj-1 |
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| 436 | DO ji = fs_2, fs_jpim1 |
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| 437 | rswitch = ( 1.0 - MAX( 0._wp, SIGN( 1._wp, -zmass1(ji,jj) ) ) ) * umask(ji,jj,1) |
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| 438 | z0 = zmass1(ji,jj) * z1_dtevp |
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| 439 | |
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| 440 | ! SB modif because ocean has no slip boundary condition |
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| 441 | zv_ice1 = 0.5 * ( ( v_ice(ji ,jj) + v_ice(ji ,jj-1) ) * e1t(ji ,jj) & |
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| 442 | & + ( v_ice(ji+1,jj) + v_ice(ji+1,jj-1) ) * e1t(ji+1,jj) ) & |
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| 443 | & / ( e1t(ji+1,jj) + e1t(ji,jj) ) * umask(ji,jj,1) |
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| 444 | za = rhoco * SQRT( ( u_ice(ji,jj) - u_oce(ji,jj) )**2 + & |
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| 445 | & ( zv_ice1 - v_oce1(ji,jj) )**2 ) * ( 1.0 - zfrld1(ji,jj) ) |
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| 446 | zr = z0 * u_ice(ji,jj) + zf1(ji,jj) + za1ct(ji,jj) + za * u_oce(ji,jj) |
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| 447 | zcca = z0 + za |
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| 448 | zccb = zcorl1(ji,jj) |
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| 449 | u_ice(ji,jj) = ( zr + zccb * zv_ice1 ) / ( zcca + zepsi ) * rswitch |
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| 450 | END DO |
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| 451 | END DO |
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| 452 | |
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| 453 | CALL lbc_lnk( u_ice(:,:), 'U', -1. ) |
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| 454 | #if defined key_agrif && defined key_lim2 |
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| 455 | CALL agrif_rhg_lim2( jter, nn_nevp, 'U' ) |
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| 456 | #endif |
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| 457 | #if defined key_bdy |
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| 458 | CALL bdy_ice_lim_dyn( 'U' ) |
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| 459 | #endif |
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| 460 | |
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| 461 | DO jj = k_j1+1, k_jpj-1 |
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| 462 | DO ji = fs_2, fs_jpim1 |
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| 463 | |
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| 464 | rswitch = ( 1.0 - MAX( 0._wp, SIGN( 1._wp, -zmass2(ji,jj) ) ) ) * vmask(ji,jj,1) |
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| 465 | z0 = zmass2(ji,jj) * z1_dtevp |
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| 466 | ! SB modif because ocean has no slip boundary condition |
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| 467 | zu_ice2 = 0.5 * ( ( u_ice(ji,jj ) + u_ice(ji-1,jj ) ) * e2t(ji,jj) & |
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| 468 | & + ( u_ice(ji,jj+1) + u_ice(ji-1,jj+1) ) * e2t(ji,jj+1) ) & |
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| 469 | & / ( e2t(ji,jj+1) + e2t(ji,jj) ) * vmask(ji,jj,1) |
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| 470 | za = rhoco * SQRT( ( zu_ice2 - u_oce2(ji,jj) )**2 + & |
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| 471 | & ( v_ice(ji,jj) - v_oce(ji,jj))**2 ) * ( 1.0 - zfrld2(ji,jj) ) |
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| 472 | zr = z0 * v_ice(ji,jj) + zf2(ji,jj) + za2ct(ji,jj) + za * v_oce(ji,jj) |
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| 473 | zcca = z0 + za |
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| 474 | zccb = zcorl2(ji,jj) |
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| 475 | v_ice(ji,jj) = ( zr - zccb * zu_ice2 ) / ( zcca + zepsi ) * rswitch |
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| 476 | END DO |
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| 477 | END DO |
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| 478 | |
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| 479 | CALL lbc_lnk( v_ice(:,:), 'V', -1. ) |
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| 480 | #if defined key_agrif && defined key_lim2 |
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| 481 | CALL agrif_rhg_lim2( jter, nn_nevp, 'V' ) |
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| 482 | #endif |
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| 483 | #if defined key_bdy |
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| 484 | CALL bdy_ice_lim_dyn( 'V' ) |
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| 485 | #endif |
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| 486 | |
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| 487 | ELSE |
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| 488 | DO jj = k_j1+1, k_jpj-1 |
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| 489 | DO ji = fs_2, fs_jpim1 |
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| 490 | rswitch = ( 1.0 - MAX( 0._wp, SIGN( 1._wp, -zmass2(ji,jj) ) ) ) * vmask(ji,jj,1) |
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| 491 | z0 = zmass2(ji,jj) * z1_dtevp |
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| 492 | ! SB modif because ocean has no slip boundary condition |
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| 493 | zu_ice2 = 0.5 * ( ( u_ice(ji,jj ) + u_ice(ji-1,jj ) ) * e2t(ji,jj) & |
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| 494 | & +( u_ice(ji,jj+1) + u_ice(ji-1,jj+1) ) * e2t(ji,jj+1) ) & |
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| 495 | & / ( e2t(ji,jj+1) + e2t(ji,jj) ) * vmask(ji,jj,1) |
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| 496 | |
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| 497 | za = rhoco * SQRT( ( zu_ice2 - u_oce2(ji,jj) )**2 + & |
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| 498 | & ( v_ice(ji,jj) - v_oce(ji,jj) )**2 ) * ( 1.0 - zfrld2(ji,jj) ) |
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| 499 | zr = z0 * v_ice(ji,jj) + zf2(ji,jj) + za2ct(ji,jj) + za * v_oce(ji,jj) |
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| 500 | zcca = z0 + za |
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| 501 | zccb = zcorl2(ji,jj) |
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| 502 | v_ice(ji,jj) = ( zr - zccb * zu_ice2 ) / ( zcca + zepsi ) * rswitch |
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| 503 | END DO |
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| 504 | END DO |
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| 505 | |
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| 506 | CALL lbc_lnk( v_ice(:,:), 'V', -1. ) |
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| 507 | #if defined key_agrif && defined key_lim2 |
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| 508 | CALL agrif_rhg_lim2( jter, nn_nevp, 'V' ) |
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| 509 | #endif |
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| 510 | #if defined key_bdy |
|---|
| 511 | CALL bdy_ice_lim_dyn( 'V' ) |
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| 512 | #endif |
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| 513 | |
|---|
| 514 | DO jj = k_j1+1, k_jpj-1 |
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| 515 | DO ji = fs_2, fs_jpim1 |
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| 516 | rswitch = ( 1.0 - MAX( 0._wp, SIGN( 1._wp, -zmass1(ji,jj) ) ) ) * umask(ji,jj,1) |
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| 517 | z0 = zmass1(ji,jj) * z1_dtevp |
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| 518 | zv_ice1 = 0.5 * ( ( v_ice(ji ,jj) + v_ice(ji ,jj-1) ) * e1t(ji,jj) & |
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| 519 | & + ( v_ice(ji+1,jj) + v_ice(ji+1,jj-1) ) * e1t(ji+1,jj) ) & |
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| 520 | & / ( e1t(ji+1,jj) + e1t(ji,jj) ) * umask(ji,jj,1) |
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| 521 | |
|---|
| 522 | za = rhoco * SQRT( ( u_ice(ji,jj) - u_oce(ji,jj) )**2 + & |
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| 523 | & ( zv_ice1 - v_oce1(ji,jj) )**2 ) * ( 1.0 - zfrld1(ji,jj) ) |
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| 524 | zr = z0 * u_ice(ji,jj) + zf1(ji,jj) + za1ct(ji,jj) + za * u_oce(ji,jj) |
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| 525 | zcca = z0 + za |
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| 526 | zccb = zcorl1(ji,jj) |
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| 527 | u_ice(ji,jj) = ( zr + zccb * zv_ice1 ) / ( zcca + zepsi ) * rswitch |
|---|
| 528 | END DO |
|---|
| 529 | END DO |
|---|
| 530 | |
|---|
| 531 | CALL lbc_lnk( u_ice(:,:), 'U', -1. ) |
|---|
| 532 | #if defined key_agrif && defined key_lim2 |
|---|
| 533 | CALL agrif_rhg_lim2( jter, nn_nevp, 'U' ) |
|---|
| 534 | #endif |
|---|
| 535 | #if defined key_bdy |
|---|
| 536 | CALL bdy_ice_lim_dyn( 'U' ) |
|---|
| 537 | #endif |
|---|
| 538 | |
|---|
| 539 | ENDIF |
|---|
| 540 | |
|---|
| 541 | IF(ln_ctl) THEN |
|---|
| 542 | !--- Convergence test. |
|---|
| 543 | DO jj = k_j1+1 , k_jpj-1 |
|---|
| 544 | zresr(:,jj) = MAX( ABS( u_ice(:,jj) - zu_ice(:,jj) ), ABS( v_ice(:,jj) - zv_ice(:,jj) ) ) |
|---|
| 545 | END DO |
|---|
| 546 | zresm = MAXVAL( zresr( 1:jpi, k_j1+1:k_jpj-1 ) ) |
|---|
| 547 | IF( lk_mpp ) CALL mpp_max( zresm ) ! max over the global domain |
|---|
| 548 | ENDIF |
|---|
| 549 | |
|---|
| 550 | ! ! ==================== ! |
|---|
| 551 | END DO ! end loop over jter ! |
|---|
| 552 | ! ! ==================== ! |
|---|
| 553 | ! |
|---|
| 554 | !------------------------------------------------------------------------------! |
|---|
| 555 | ! 4) Prevent ice velocities when the ice is thin |
|---|
| 556 | !------------------------------------------------------------------------------! |
|---|
| 557 | ! If the ice volume is below zvmin then ice velocity should equal the |
|---|
| 558 | ! ocean velocity. This prevents high velocity when ice is thin |
|---|
| 559 | DO jj = k_j1+1, k_jpj-1 |
|---|
| 560 | DO ji = fs_2, fs_jpim1 |
|---|
| 561 | IF ( vt_i(ji,jj) <= zvmin ) THEN |
|---|
| 562 | u_ice(ji,jj) = u_oce(ji,jj) |
|---|
| 563 | v_ice(ji,jj) = v_oce(ji,jj) |
|---|
| 564 | ENDIF |
|---|
| 565 | END DO |
|---|
| 566 | END DO |
|---|
| 567 | |
|---|
| 568 | CALL lbc_lnk_multi( u_ice(:,:), 'U', -1., v_ice(:,:), 'V', -1. ) |
|---|
| 569 | |
|---|
| 570 | #if defined key_agrif && defined key_lim2 |
|---|
| 571 | CALL agrif_rhg_lim2( nn_nevp , nn_nevp, 'U' ) |
|---|
| 572 | CALL agrif_rhg_lim2( nn_nevp , nn_nevp, 'V' ) |
|---|
| 573 | #endif |
|---|
| 574 | #if defined key_bdy |
|---|
| 575 | CALL bdy_ice_lim_dyn( 'U' ) |
|---|
| 576 | CALL bdy_ice_lim_dyn( 'V' ) |
|---|
| 577 | #endif |
|---|
| 578 | |
|---|
| 579 | DO jj = k_j1+1, k_jpj-1 |
|---|
| 580 | DO ji = fs_2, fs_jpim1 |
|---|
| 581 | IF ( vt_i(ji,jj) <= zvmin ) THEN |
|---|
| 582 | v_ice1(ji,jj) = 0.5_wp * ( ( v_ice(ji ,jj) + v_ice(ji, jj-1) ) * e1t(ji+1,jj) & |
|---|
| 583 | & + ( v_ice(ji+1,jj) + v_ice(ji+1,jj-1) ) * e1t(ji ,jj) ) & |
|---|
| 584 | & / ( e1t(ji+1,jj) + e1t(ji,jj) ) * umask(ji,jj,1) |
|---|
| 585 | |
|---|
| 586 | u_ice2(ji,jj) = 0.5_wp * ( ( u_ice(ji,jj ) + u_ice(ji-1,jj ) ) * e2t(ji,jj+1) & |
|---|
| 587 | & + ( u_ice(ji,jj+1) + u_ice(ji-1,jj+1) ) * e2t(ji,jj ) ) & |
|---|
| 588 | & / ( e2t(ji,jj+1) + e2t(ji,jj) ) * vmask(ji,jj,1) |
|---|
| 589 | ENDIF |
|---|
| 590 | END DO |
|---|
| 591 | END DO |
|---|
| 592 | |
|---|
| 593 | CALL lbc_lnk_multi( u_ice2(:,:), 'V', -1., v_ice1(:,:), 'U', -1. ) |
|---|
| 594 | |
|---|
| 595 | ! Recompute delta, shear and div, inputs for mechanical redistribution |
|---|
| 596 | DO jj = k_j1+1, k_jpj-1 |
|---|
| 597 | DO ji = fs_2, jpim1 !RB bug no vect opt due to zmask |
|---|
| 598 | !- divu_i(:,:), zdt(:,:): divergence and tension at centre |
|---|
| 599 | !- zds(:,:): shear on northeast corner of grid cells |
|---|
| 600 | IF ( vt_i(ji,jj) <= zvmin ) THEN |
|---|
| 601 | |
|---|
| 602 | divu_i(ji,jj) = ( e2u(ji,jj) * u_ice(ji,jj) - e2u(ji-1,jj ) * u_ice(ji-1,jj ) & |
|---|
| 603 | & + e1v(ji,jj) * v_ice(ji,jj) - e1v(ji ,jj-1) * v_ice(ji ,jj-1) & |
|---|
| 604 | & ) * r1_e1e2t(ji,jj) |
|---|
| 605 | |
|---|
| 606 | zdt(ji,jj) = ( ( u_ice(ji,jj) * r1_e2u(ji,jj) - u_ice(ji-1,jj) * r1_e2u(ji-1,jj) ) * e2t(ji,jj) * e2t(ji,jj) & |
|---|
| 607 | & -( v_ice(ji,jj) * r1_e1v(ji,jj) - v_ice(ji,jj-1) * r1_e1v(ji,jj-1) ) * e1t(ji,jj) * e1t(ji,jj) & |
|---|
| 608 | & ) * r1_e1e2t(ji,jj) |
|---|
| 609 | ! |
|---|
| 610 | ! SB modif because ocean has no slip boundary condition |
|---|
| 611 | zds(ji,jj) = ( ( u_ice(ji,jj+1) * r1_e1u(ji,jj+1) - u_ice(ji,jj) * r1_e1u(ji,jj) ) * e1f(ji,jj) * e1f(ji,jj) & |
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| 612 | & +( v_ice(ji+1,jj) * r1_e2v(ji+1,jj) - v_ice(ji,jj) * r1_e2v(ji,jj) ) * e2f(ji,jj) * e2f(ji,jj) & |
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| 613 | & ) * r1_e1e2f(ji,jj) * ( 2.0 - fmask(ji,jj,1) ) & |
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| 614 | & * zmask(ji,jj) * zmask(ji,jj+1) * zmask(ji+1,jj) * zmask(ji+1,jj+1) |
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| 615 | |
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| 616 | zdst = ( e2u(ji,jj) * v_ice1(ji,jj) - e2u(ji-1,jj ) * v_ice1(ji-1,jj ) & |
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| 617 | & + e1v(ji,jj) * u_ice2(ji,jj) - e1v(ji ,jj-1) * u_ice2(ji ,jj-1) ) * r1_e1e2t(ji,jj) |
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| 618 | |
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| 619 | delta = SQRT( divu_i(ji,jj)**2 + ( zdt(ji,jj)**2 + zdst**2 ) * usecc2 ) |
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| 620 | delta_i(ji,jj) = delta + rn_creepl |
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| 621 | |
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| 622 | ENDIF |
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| 623 | END DO |
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| 624 | END DO |
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| 625 | ! |
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| 626 | !------------------------------------------------------------------------------! |
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| 627 | ! 5) Store stress tensor and its invariants |
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| 628 | !------------------------------------------------------------------------------! |
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| 629 | ! * Invariants of the stress tensor are required for limitd_me |
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| 630 | ! (accelerates convergence and improves stability) |
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| 631 | DO jj = k_j1+1, k_jpj-1 |
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| 632 | DO ji = fs_2, fs_jpim1 |
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| 633 | zdst = ( e2u(ji,jj) * v_ice1(ji,jj) - e2u( ji-1, jj ) * v_ice1(ji-1,jj) & |
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| 634 | & + e1v(ji,jj) * u_ice2(ji,jj) - e1v( ji , jj-1 ) * u_ice2(ji,jj-1) ) * r1_e1e2t(ji,jj) |
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| 635 | shear_i(ji,jj) = SQRT( zdt(ji,jj) * zdt(ji,jj) + zdst * zdst ) |
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| 636 | END DO |
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| 637 | END DO |
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| 638 | |
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| 639 | ! Lateral boundary condition |
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| 640 | CALL lbc_lnk_multi( divu_i (:,:), 'T', 1., delta_i(:,:), 'T', 1., shear_i(:,:), 'T', 1. ) |
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| 641 | |
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| 642 | ! * Store the stress tensor for the next time step |
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| 643 | stress1_i (:,:) = zs1 (:,:) |
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| 644 | stress2_i (:,:) = zs2 (:,:) |
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| 645 | stress12_i(:,:) = zs12(:,:) |
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| 646 | |
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| 647 | ! |
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| 648 | !------------------------------------------------------------------------------! |
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| 649 | ! 6) Control prints of residual and charge ellipse |
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| 650 | !------------------------------------------------------------------------------! |
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| 651 | ! |
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| 652 | ! print the residual for convergence |
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| 653 | IF(ln_ctl) THEN |
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| 654 | WRITE(charout,FMT="('lim_rhg : res =',D23.16, ' iter =',I4)") zresm, jter |
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| 655 | CALL prt_ctl_info(charout) |
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| 656 | CALL prt_ctl(tab2d_1=u_ice, clinfo1=' lim_rhg : u_ice :', tab2d_2=v_ice, clinfo2=' v_ice :') |
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| 657 | ENDIF |
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| 658 | |
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| 659 | ! print charge ellipse |
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| 660 | ! This can be desactivated once the user is sure that the stress state |
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| 661 | ! lie on the charge ellipse. See Bouillon et al. 08 for more details |
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| 662 | IF(ln_ctl) THEN |
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| 663 | CALL prt_ctl_info('lim_rhg : numit :',ivar1=numit) |
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| 664 | CALL prt_ctl_info('lim_rhg : nwrite :',ivar1=nwrite) |
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| 665 | CALL prt_ctl_info('lim_rhg : MOD :',ivar1=MOD(numit,nwrite)) |
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| 666 | IF( MOD(numit,nwrite) .EQ. 0 ) THEN |
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| 667 | WRITE(charout,FMT="('lim_rhg :', I4, I6, I1, I1, A10)") 1000, numit, 0, 0, ' ch. ell. ' |
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| 668 | CALL prt_ctl_info(charout) |
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| 669 | DO jj = k_j1+1, k_jpj-1 |
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| 670 | DO ji = 2, jpim1 |
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| 671 | IF (zpresh(ji,jj) > 1.0) THEN |
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| 672 | sigma1 = ( zs1(ji,jj) + (zs2(ji,jj)**2 + 4*zs12(ji,jj)**2 )**0.5 ) / ( 2*zpresh(ji,jj) ) |
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| 673 | sigma2 = ( zs1(ji,jj) - (zs2(ji,jj)**2 + 4*zs12(ji,jj)**2 )**0.5 ) / ( 2*zpresh(ji,jj) ) |
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| 674 | WRITE(charout,FMT="('lim_rhg :', I4, I4, D23.16, D23.16, D23.16, D23.16, A10)") |
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| 675 | CALL prt_ctl_info(charout) |
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| 676 | ENDIF |
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| 677 | END DO |
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| 678 | END DO |
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| 679 | WRITE(charout,FMT="('lim_rhg :', I4, I6, I1, I1, A10)") 2000, numit, 0, 0, ' ch. ell. ' |
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| 680 | CALL prt_ctl_info(charout) |
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| 681 | ENDIF |
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| 682 | ENDIF |
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| 683 | ! |
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| 684 | |
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| 685 | END SUBROUTINE lim_rhg |
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| 686 | |
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| 687 | #else |
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| 688 | !!---------------------------------------------------------------------- |
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| 689 | !! Default option Dummy module NO LIM sea-ice model |
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| 690 | !!---------------------------------------------------------------------- |
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| 691 | CONTAINS |
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| 692 | SUBROUTINE lim_rhg( k1 , k2 ) ! Dummy routine |
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| 693 | WRITE(*,*) 'lim_rhg: You should not have seen this print! error?', k1, k2 |
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| 694 | END SUBROUTINE lim_rhg |
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| 695 | #endif |
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| 696 | |
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| 697 | !!============================================================================== |
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| 698 | END MODULE limrhg |
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