| 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 wrk_nemo ! work arrays |
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| 37 | USE in_out_manager ! I/O manager |
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| 38 | USE prtctl ! Print control |
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| 39 | USE lib_fortran ! Fortran utilities (allows no signed zero when 'key_nosignedzero' defined) |
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| 40 | #if defined key_agrif && defined key_lim2 |
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| 41 | USE agrif_lim2_interp |
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| 42 | #endif |
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| 43 | #if defined key_agrif && defined key_lim3 |
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| 44 | USE agrif_lim3_interp |
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| 45 | #endif |
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| 46 | #if defined key_bdy |
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| 47 | USE bdyice_lim |
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| 48 | #endif |
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| 49 | |
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| 50 | IMPLICIT NONE |
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| 51 | PRIVATE |
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| 52 | |
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| 53 | PUBLIC lim_rhg ! routine called by lim_dyn (or lim_dyn_2) |
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| 54 | |
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| 55 | !! * Substitutions |
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| 56 | # include "vectopt_loop_substitute.h90" |
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| 57 | !!---------------------------------------------------------------------- |
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| 58 | !! NEMO/LIM3 4.0 , UCL - NEMO Consortium (2011) |
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| 59 | !! $Id$ |
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| 60 | !! Software governed by the CeCILL licence (NEMOGCM/NEMO_CeCILL.txt) |
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| 61 | !!---------------------------------------------------------------------- |
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| 62 | CONTAINS |
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| 63 | |
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| 64 | SUBROUTINE lim_rhg( k_j1, k_jpj ) |
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| 65 | !!------------------------------------------------------------------- |
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| 66 | !! *** SUBROUTINE lim_rhg *** |
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| 67 | !! EVP-C-grid |
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| 68 | !! |
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| 69 | !! ** purpose : determines sea ice drift from wind stress, ice-ocean |
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| 70 | !! stress and sea-surface slope. Ice-ice interaction is described by |
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| 71 | !! a non-linear elasto-viscous-plastic (EVP) law including shear |
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| 72 | !! strength and a bulk rheology (Hunke and Dukowicz, 2002). |
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| 73 | !! |
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| 74 | !! The points in the C-grid look like this, dear reader |
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| 75 | !! |
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| 76 | !! (ji,jj) |
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| 77 | !! | |
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| 78 | !! | |
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| 79 | !! (ji-1,jj) | (ji,jj) |
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| 80 | !! --------- |
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| 81 | !! | | |
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| 82 | !! | (ji,jj) |------(ji,jj) |
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| 83 | !! | | |
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| 84 | !! --------- |
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| 85 | !! (ji-1,jj-1) (ji,jj-1) |
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| 86 | !! |
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| 87 | !! ** Inputs : - wind forcing (stress), oceanic currents |
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| 88 | !! ice total volume (vt_i) per unit area |
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| 89 | !! snow total volume (vt_s) per unit area |
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| 90 | !! |
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| 91 | !! ** Action : - compute u_ice, v_ice : the components of the |
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| 92 | !! sea-ice velocity vector |
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| 93 | !! - compute delta_i, shear_i, divu_i, which are inputs |
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| 94 | !! of the ice thickness distribution |
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| 95 | !! |
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| 96 | !! ** Steps : 1) Compute ice snow mass, ice strength |
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| 97 | !! 2) Compute wind, oceanic stresses, mass terms and |
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| 98 | !! coriolis terms of the momentum equation |
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| 99 | !! 3) Solve the momentum equation (iterative procedure) |
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| 100 | !! 4) Prevent high velocities if the ice is thin |
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| 101 | !! 5) Recompute invariants of the strain rate tensor |
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| 102 | !! which are inputs of the ITD, store stress |
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| 103 | !! for the next time step |
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| 104 | !! 6) Control prints of residual (convergence) |
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| 105 | !! and charge ellipse. |
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| 106 | !! The user should make sure that the parameters |
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| 107 | !! nn_nevp, elastic time scale and rn_creepl maintain stress state |
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| 108 | !! on the charge ellipse for plastic flow |
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| 109 | !! e.g. in the Canadian Archipelago |
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| 110 | !! |
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| 111 | !! References : Hunke and Dukowicz, JPO97 |
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| 112 | !! Bouillon et al., Ocean Modelling 2009 |
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| 113 | !!------------------------------------------------------------------- |
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| 114 | INTEGER, INTENT(in) :: k_j1 ! southern j-index for ice computation |
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| 115 | INTEGER, INTENT(in) :: k_jpj ! northern j-index for ice computation |
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| 116 | !! |
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| 117 | INTEGER :: ji, jj ! dummy loop indices |
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| 118 | INTEGER :: jter ! local integers |
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| 119 | CHARACTER (len=50) :: charout |
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| 120 | REAL(wp) :: zt11, zt12, zt21, zt22, ztagnx, ztagny, delta ! |
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| 121 | REAL(wp) :: za, zstms ! local scalars |
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| 122 | REAL(wp) :: zc1, zc2, zc3 ! ice mass |
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| 123 | |
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| 124 | REAL(wp) :: dtevp , z1_dtevp ! time step for subcycling |
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| 125 | REAL(wp) :: dtotel, z1_dtotel, ecc2, ecci ! square of yield ellipse eccenticity |
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| 126 | REAL(wp) :: z0, zr, zcca, zccb ! temporary scalars |
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| 127 | REAL(wp) :: zu_ice2, zv_ice1 ! |
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| 128 | REAL(wp) :: zddc, zdtc ! delta on corners and on centre |
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| 129 | REAL(wp) :: zdst ! shear at the center of the grid point |
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| 130 | REAL(wp) :: zdsshx, zdsshy ! term for the gradient of ocean surface |
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| 131 | REAL(wp) :: sigma1, sigma2 ! internal ice stress |
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| 132 | |
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| 133 | REAL(wp) :: zresm ! Maximal error on ice velocity |
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| 134 | REAL(wp) :: zintb, zintn ! dummy argument |
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| 135 | |
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| 136 | REAL(wp), POINTER, DIMENSION(:,:) :: zpresh ! temporary array for ice strength |
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| 137 | REAL(wp), POINTER, DIMENSION(:,:) :: zpreshc ! Ice strength on grid cell corners (zpreshc) |
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| 138 | REAL(wp), POINTER, DIMENSION(:,:) :: zfrld1, zfrld2 ! lead fraction on U/V points |
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| 139 | REAL(wp), POINTER, DIMENSION(:,:) :: zmass1, zmass2 ! ice/snow mass on U/V points |
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| 140 | REAL(wp), POINTER, DIMENSION(:,:) :: zcorl1, zcorl2 ! coriolis parameter on U/V points |
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| 141 | REAL(wp), POINTER, DIMENSION(:,:) :: za1ct , za2ct ! temporary arrays |
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| 142 | REAL(wp), POINTER, DIMENSION(:,:) :: v_oce1 ! ocean u/v component on U points |
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| 143 | REAL(wp), POINTER, DIMENSION(:,:) :: u_oce2 ! ocean u/v component on V points |
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| 144 | REAL(wp), POINTER, DIMENSION(:,:) :: u_ice2, v_ice1 ! ice u/v component on V/U point |
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| 145 | REAL(wp), POINTER, DIMENSION(:,:) :: zf1 , zf2 ! arrays for internal stresses |
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| 146 | REAL(wp), POINTER, DIMENSION(:,:) :: zmask ! mask ocean grid points |
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| 147 | |
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| 148 | REAL(wp), POINTER, DIMENSION(:,:) :: zdt ! tension at centre of grid cells |
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| 149 | REAL(wp), POINTER, DIMENSION(:,:) :: zds ! Shear on northeast corner of grid cells |
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| 150 | REAL(wp), POINTER, DIMENSION(:,:) :: zs1 , zs2 ! Diagonal stress tensor components zs1 and zs2 |
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| 151 | REAL(wp), POINTER, DIMENSION(:,:) :: zs12 ! Non-diagonal stress tensor component zs12 |
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| 152 | REAL(wp), POINTER, DIMENSION(:,:) :: zu_ice, zv_ice, zresr ! Local error on velocity |
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| 153 | REAL(wp), POINTER, DIMENSION(:,:) :: zpice ! array used for the calculation of ice surface slope: |
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| 154 | ! ocean surface (ssh_m) if ice is not embedded |
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| 155 | ! ice top surface if ice is embedded |
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| 156 | |
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| 157 | REAL(wp), PARAMETER :: zepsi = 1.0e-20_wp ! tolerance parameter |
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| 158 | REAL(wp), PARAMETER :: zvmin = 1.0e-03_wp ! ice volume below which ice velocity equals ocean velocity |
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| 159 | !!------------------------------------------------------------------- |
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| 160 | |
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| 161 | CALL wrk_alloc( jpi,jpj, zpresh, zfrld1, zmass1, zcorl1, za1ct , zpreshc, zfrld2, zmass2, zcorl2, za2ct ) |
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| 162 | CALL wrk_alloc( jpi,jpj, u_oce2, u_ice2, v_oce1 , v_ice1 , zmask ) |
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| 163 | CALL wrk_alloc( jpi,jpj, zf1 , zu_ice, zf2 , zv_ice , zdt , zds ) |
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| 164 | CALL wrk_alloc( jpi,jpj, zs1 , zs2 , zs12 , zresr , zpice ) |
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| 165 | |
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| 166 | #if defined key_lim2 && ! defined key_lim2_vp |
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| 167 | # if defined key_agrif |
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| 168 | USE ice_2, vt_s => hsnm |
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| 169 | USE ice_2, vt_i => hicm |
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| 170 | # else |
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| 171 | vt_s => hsnm |
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| 172 | vt_i => hicm |
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| 173 | # endif |
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| 174 | at_i(:,:) = 1. - frld(:,:) |
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| 175 | #endif |
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| 176 | #if defined key_agrif && defined key_lim2 |
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| 177 | CALL agrif_rhg_lim2_load ! First interpolation of coarse values |
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| 178 | #endif |
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| 179 | #if defined key_agrif && defined key_lim3 |
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| 180 | CALL agrif_interp_lim3('U') ! First interpolation of coarse values |
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| 181 | CALL agrif_interp_lim3('V') ! First interpolation of coarse values |
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| 182 | #endif |
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| 183 | ! |
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| 184 | !------------------------------------------------------------------------------! |
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| 185 | ! 1) Ice strength (zpresh) ! |
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| 186 | !------------------------------------------------------------------------------! |
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| 187 | ! |
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| 188 | ! Put every vector to 0 |
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| 189 | delta_i(:,:) = 0._wp ; |
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| 190 | zpresh (:,:) = 0._wp ; |
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| 191 | zpreshc(:,:) = 0._wp |
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| 192 | u_ice2 (:,:) = 0._wp ; v_ice1(:,:) = 0._wp |
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| 193 | divu_i (:,:) = 0._wp ; zdt (:,:) = 0._wp ; zds(:,:) = 0._wp |
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| 194 | shear_i(:,:) = 0._wp |
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| 195 | |
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| 196 | #if defined key_lim3 |
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| 197 | CALL lim_itd_me_icestrength( nn_icestr ) ! LIM-3: Ice strength on T-points |
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| 198 | #endif |
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| 199 | |
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| 200 | DO jj = k_j1 , k_jpj ! Ice mass and temp variables |
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| 201 | DO ji = 1 , jpi |
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| 202 | #if defined key_lim3 |
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| 203 | zpresh(ji,jj) = tmask(ji,jj,1) * strength(ji,jj) |
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| 204 | #endif |
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| 205 | #if defined key_lim2 |
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| 206 | zpresh(ji,jj) = tmask(ji,jj,1) * pstar * vt_i(ji,jj) * EXP( -c_rhg * (1. - at_i(ji,jj) ) ) |
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| 207 | #endif |
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| 208 | ! zmask = 1 where there is ice or on land |
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| 209 | 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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| 210 | END DO |
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| 211 | END DO |
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| 212 | |
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| 213 | ! Ice strength on grid cell corners (zpreshc) |
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| 214 | ! needed for calculation of shear stress |
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| 215 | DO jj = k_j1+1, k_jpj-1 |
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| 216 | DO ji = 2, jpim1 !RB caution no fs_ (ji+1,jj+1) |
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| 217 | 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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| 218 | & 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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| 219 | 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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| 220 | & 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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| 221 | & ) / MAX( zstms, zepsi ) |
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| 222 | END DO |
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| 223 | END DO |
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| 224 | CALL lbc_lnk( zpreshc(:,:), 'F', 1. ) |
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| 225 | ! |
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| 226 | !------------------------------------------------------------------------------! |
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| 227 | ! 2) Wind / ocean stress, mass terms, coriolis terms |
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| 228 | !------------------------------------------------------------------------------! |
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| 229 | ! |
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| 230 | ! Wind stress, coriolis and mass terms on the sides of the squares |
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| 231 | ! zfrld1: lead fraction on U-points |
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| 232 | ! zfrld2: lead fraction on V-points |
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| 233 | ! zmass1: ice/snow mass on U-points |
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| 234 | ! zmass2: ice/snow mass on V-points |
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| 235 | ! zcorl1: Coriolis parameter on U-points |
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| 236 | ! zcorl2: Coriolis parameter on V-points |
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| 237 | ! (ztagnx,ztagny): wind stress on U/V points |
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| 238 | ! v_oce1: ocean v component on u points |
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| 239 | ! u_oce2: ocean u component on v points |
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| 240 | |
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| 241 | IF( nn_ice_embd == 2 ) THEN !== embedded sea ice: compute representative ice top surface ==! |
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| 242 | ! |
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| 243 | ! average interpolation coeff as used in dynspg = (1/nn_fsbc) * {SUM[n/nn_fsbc], n=0,nn_fsbc-1} |
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| 244 | ! = (1/nn_fsbc)^2 * {SUM[n], n=0,nn_fsbc-1} |
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| 245 | zintn = REAL( nn_fsbc - 1 ) / REAL( nn_fsbc ) * 0.5_wp |
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| 246 | ! |
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| 247 | ! average interpolation coeff as used in dynspg = (1/nn_fsbc) * {SUM[1-n/nn_fsbc], n=0,nn_fsbc-1} |
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| 248 | ! = (1/nn_fsbc)^2 * (nn_fsbc^2 - {SUM[n], n=0,nn_fsbc-1}) |
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| 249 | zintb = REAL( nn_fsbc + 1 ) / REAL( nn_fsbc ) * 0.5_wp |
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| 250 | ! |
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| 251 | zpice(:,:) = ssh_m(:,:) + ( zintn * snwice_mass(:,:) + zintb * snwice_mass_b(:,:) ) * r1_rau0 |
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| 252 | ! |
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| 253 | ELSE !== non-embedded sea ice: use ocean surface for slope calculation ==! |
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| 254 | zpice(:,:) = ssh_m(:,:) |
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| 255 | ENDIF |
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| 256 | |
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| 257 | DO jj = k_j1+1, k_jpj-1 |
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| 258 | DO ji = fs_2, fs_jpim1 |
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| 259 | |
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| 260 | zc1 = tmask(ji ,jj ,1) * ( rhosn * vt_s(ji ,jj ) + rhoic * vt_i(ji ,jj ) ) |
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| 261 | zc2 = tmask(ji+1,jj ,1) * ( rhosn * vt_s(ji+1,jj ) + rhoic * vt_i(ji+1,jj ) ) |
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| 262 | zc3 = tmask(ji ,jj+1,1) * ( rhosn * vt_s(ji ,jj+1) + rhoic * vt_i(ji ,jj+1) ) |
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| 263 | |
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| 264 | zt11 = tmask(ji ,jj,1) * e1t(ji ,jj) |
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| 265 | zt12 = tmask(ji+1,jj,1) * e1t(ji+1,jj) |
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| 266 | zt21 = tmask(ji,jj ,1) * e2t(ji,jj ) |
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| 267 | zt22 = tmask(ji,jj+1,1) * e2t(ji,jj+1) |
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| 268 | |
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| 269 | ! Leads area. |
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| 270 | 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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| 271 | 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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| 272 | |
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| 273 | ! Mass, coriolis coeff. and currents |
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| 274 | zmass1(ji,jj) = ( zt12 * zc1 + zt11 * zc2 ) / ( zt11 + zt12 + zepsi ) |
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| 275 | zmass2(ji,jj) = ( zt22 * zc1 + zt21 * zc3 ) / ( zt21 + zt22 + zepsi ) |
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| 276 | zcorl1(ji,jj) = zmass1(ji,jj) * ( e1t(ji+1,jj) * fcor(ji,jj) + e1t(ji,jj) * fcor(ji+1,jj) ) & |
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| 277 | & / ( e1t(ji,jj) + e1t(ji+1,jj) + zepsi ) |
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| 278 | zcorl2(ji,jj) = zmass2(ji,jj) * ( e2t(ji,jj+1) * fcor(ji,jj) + e2t(ji,jj) * fcor(ji,jj+1) ) & |
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| 279 | & / ( e2t(ji,jj+1) + e2t(ji,jj) + zepsi ) |
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| 280 | ! |
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| 281 | ! Ocean has no slip boundary condition |
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| 282 | v_oce1(ji,jj) = 0.5 * ( ( v_oce(ji ,jj) + v_oce(ji ,jj-1) ) * e1t(ji,jj) & |
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| 283 | & + ( v_oce(ji+1,jj) + v_oce(ji+1,jj-1) ) * e1t(ji+1,jj) ) & |
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| 284 | & / ( e1t(ji+1,jj) + e1t(ji,jj) ) * umask(ji,jj,1) |
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| 285 | |
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| 286 | u_oce2(ji,jj) = 0.5 * ( ( u_oce(ji,jj ) + u_oce(ji-1,jj ) ) * e2t(ji,jj) & |
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| 287 | & + ( u_oce(ji,jj+1) + u_oce(ji-1,jj+1) ) * e2t(ji,jj+1) ) & |
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| 288 | & / ( e2t(ji,jj+1) + e2t(ji,jj) ) * vmask(ji,jj,1) |
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| 289 | |
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| 290 | ! Wind stress at U,V-point |
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| 291 | ztagnx = ( 1. - zfrld1(ji,jj) ) * utau_ice(ji,jj) |
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| 292 | ztagny = ( 1. - zfrld2(ji,jj) ) * vtau_ice(ji,jj) |
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| 293 | |
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| 294 | ! Computation of the velocity field taking into account the ice internal interaction. |
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| 295 | ! Terms that are independent of the velocity field. |
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| 296 | |
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| 297 | ! SB On utilise maintenant le gradient de la pente de l'ocean |
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| 298 | ! include it later |
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| 299 | |
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| 300 | zdsshx = ( zpice(ji+1,jj) - zpice(ji,jj) ) * r1_e1u(ji,jj) |
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| 301 | zdsshy = ( zpice(ji,jj+1) - zpice(ji,jj) ) * r1_e2v(ji,jj) |
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| 302 | |
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| 303 | za1ct(ji,jj) = ztagnx - zmass1(ji,jj) * grav * zdsshx |
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| 304 | za2ct(ji,jj) = ztagny - zmass2(ji,jj) * grav * zdsshy |
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| 305 | |
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| 306 | END DO |
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| 307 | END DO |
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| 308 | |
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| 309 | ! |
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| 310 | !------------------------------------------------------------------------------! |
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| 311 | ! 3) Solution of the momentum equation, iterative procedure |
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| 312 | !------------------------------------------------------------------------------! |
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| 313 | ! |
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| 314 | ! Time step for subcycling |
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| 315 | dtevp = rdt_ice / nn_nevp |
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| 316 | #if defined key_lim3 |
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| 317 | dtotel = dtevp / ( 2._wp * rn_relast * rdt_ice ) |
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| 318 | #else |
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| 319 | dtotel = dtevp / ( 2._wp * telast ) |
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| 320 | #endif |
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| 321 | z1_dtotel = 1._wp / ( 1._wp + dtotel ) |
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| 322 | z1_dtevp = 1._wp / dtevp |
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| 323 | !-ecc2: square of yield ellipse eccenticrity (reminder: must become a namelist parameter) |
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| 324 | ecc2 = rn_ecc * rn_ecc |
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| 325 | ecci = 1. / ecc2 |
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| 326 | |
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| 327 | !-Initialise stress tensor |
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| 328 | zs1 (:,:) = stress1_i (:,:) |
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| 329 | zs2 (:,:) = stress2_i (:,:) |
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| 330 | zs12(:,:) = stress12_i(:,:) |
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| 331 | |
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| 332 | ! !----------------------! |
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| 333 | DO jter = 1 , nn_nevp ! loop over jter ! |
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| 334 | ! !----------------------! |
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| 335 | DO jj = k_j1, k_jpj-1 |
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| 336 | zu_ice(:,jj) = u_ice(:,jj) ! velocity at previous time step |
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| 337 | zv_ice(:,jj) = v_ice(:,jj) |
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| 338 | END DO |
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| 339 | |
|---|
| 340 | DO jj = k_j1+1, k_jpj-1 |
|---|
| 341 | DO ji = fs_2, fs_jpim1 !RB bug no vect opt due to zmask |
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| 342 | |
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| 343 | ! |
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| 344 | !- Divergence, tension and shear (Section a. Appendix B of Hunke & Dukowicz, 2002) |
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| 345 | !- divu_i(:,:), zdt(:,:): divergence and tension at centre of grid cells |
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| 346 | !- zds(:,:): shear on northeast corner of grid cells |
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| 347 | ! |
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| 348 | !- IMPORTANT REMINDER: Dear Gurvan, note that, the way these terms are coded, |
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| 349 | ! there are many repeated calculations. |
|---|
| 350 | ! Speed could be improved by regrouping terms. For |
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| 351 | ! the moment, however, the stress is on clarity of coding to avoid |
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| 352 | ! bugs (Martin, for Miguel). |
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| 353 | ! |
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| 354 | !- ALSO: arrays zdt, zds and delta could |
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| 355 | ! be removed in the future to minimise memory demand. |
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| 356 | ! |
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| 357 | !- MORE NOTES: Note that we are calculating deformation rates and stresses on the corners of |
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| 358 | ! grid cells, exactly as in the B grid case. For simplicity, the indexation on |
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| 359 | ! the corners is the same as in the B grid. |
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| 360 | ! |
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| 361 | ! |
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| 362 | divu_i(ji,jj) = ( e2u(ji,jj) * u_ice(ji,jj) - e2u(ji-1,jj) * u_ice(ji-1,jj) & |
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| 363 | & + e1v(ji,jj) * v_ice(ji,jj) - e1v(ji,jj-1) * v_ice(ji,jj-1) & |
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| 364 | & ) * r1_e12t(ji,jj) |
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| 365 | |
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| 366 | 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) & |
|---|
| 367 | & - ( 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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| 368 | & ) * r1_e12t(ji,jj) |
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| 369 | |
|---|
| 370 | ! |
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| 371 | 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) & |
|---|
| 372 | & + ( 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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| 373 | & ) * r1_e12f(ji,jj) * ( 2._wp - fmask(ji,jj,1) ) & |
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| 374 | & * zmask(ji,jj) * zmask(ji,jj+1) * zmask(ji+1,jj) * zmask(ji+1,jj+1) |
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| 375 | |
|---|
| 376 | |
|---|
| 377 | v_ice1(ji,jj) = 0.5_wp * ( ( v_ice(ji ,jj) + v_ice(ji ,jj-1) ) * e1t(ji+1,jj) & |
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| 378 | & + ( v_ice(ji+1,jj) + v_ice(ji+1,jj-1) ) * e1t(ji ,jj) ) & |
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| 379 | & / ( e1t(ji+1,jj) + e1t(ji,jj) ) * umask(ji,jj,1) |
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| 380 | |
|---|
| 381 | u_ice2(ji,jj) = 0.5_wp * ( ( u_ice(ji,jj ) + u_ice(ji-1,jj ) ) * e2t(ji,jj+1) & |
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| 382 | & + ( u_ice(ji,jj+1) + u_ice(ji-1,jj+1) ) * e2t(ji,jj ) ) & |
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| 383 | & / ( e2t(ji,jj+1) + e2t(ji,jj) ) * vmask(ji,jj,1) |
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| 384 | END DO |
|---|
| 385 | END DO |
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| 386 | |
|---|
| 387 | CALL lbc_lnk_multi( v_ice1, 'U', -1., u_ice2, 'V', -1. ) ! lateral boundary cond. |
|---|
| 388 | |
|---|
| 389 | DO jj = k_j1+1, k_jpj-1 |
|---|
| 390 | DO ji = fs_2, fs_jpim1 |
|---|
| 391 | |
|---|
| 392 | !- Calculate Delta at centre of grid cells |
|---|
| 393 | zdst = ( e2u(ji,jj) * v_ice1(ji,jj) - e2u(ji-1,jj ) * v_ice1(ji-1,jj ) & |
|---|
| 394 | & + e1v(ji,jj) * u_ice2(ji,jj) - e1v(ji ,jj-1) * u_ice2(ji ,jj-1) & |
|---|
| 395 | & ) * r1_e12t(ji,jj) |
|---|
| 396 | |
|---|
| 397 | delta = SQRT( divu_i(ji,jj)**2 + ( zdt(ji,jj)**2 + zdst**2 ) * usecc2 ) |
|---|
| 398 | delta_i(ji,jj) = delta + rn_creepl |
|---|
| 399 | |
|---|
| 400 | !- Calculate Delta on corners |
|---|
| 401 | 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) & |
|---|
| 402 | & + ( u_ice2(ji+1,jj) * r1_e2v(ji+1,jj) - u_ice2(ji,jj) * r1_e2v(ji,jj) ) * e2f(ji,jj) * e2f(ji,jj) & |
|---|
| 403 | & ) * r1_e12f(ji,jj) |
|---|
| 404 | |
|---|
| 405 | 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) & |
|---|
| 406 | & + ( u_ice2(ji+1,jj) * r1_e2v(ji+1,jj) - u_ice2(ji,jj) * r1_e2v(ji,jj) ) * e2f(ji,jj) * e2f(ji,jj) & |
|---|
| 407 | & ) * r1_e12f(ji,jj) |
|---|
| 408 | |
|---|
| 409 | zddc = SQRT( zddc**2 + ( zdtc**2 + zds(ji,jj)**2 ) * usecc2 ) + rn_creepl |
|---|
| 410 | |
|---|
| 411 | !-Calculate stress tensor components zs1 and zs2 at centre of grid cells (see section 3.5 of CICE user's guide). |
|---|
| 412 | zs1(ji,jj) = ( zs1 (ji,jj) + dtotel * ( divu_i(ji,jj) - delta ) / delta_i(ji,jj) * zpresh(ji,jj) & |
|---|
| 413 | & ) * z1_dtotel |
|---|
| 414 | zs2(ji,jj) = ( zs2 (ji,jj) + dtotel * ecci * zdt(ji,jj) / delta_i(ji,jj) * zpresh(ji,jj) & |
|---|
| 415 | & ) * z1_dtotel |
|---|
| 416 | !-Calculate stress tensor component zs12 at corners |
|---|
| 417 | zs12(ji,jj) = ( zs12(ji,jj) + dtotel * ecci * zds(ji,jj) / ( 2._wp * zddc ) * zpreshc(ji,jj) & |
|---|
| 418 | & ) * z1_dtotel |
|---|
| 419 | |
|---|
| 420 | END DO |
|---|
| 421 | END DO |
|---|
| 422 | |
|---|
| 423 | CALL lbc_lnk_multi( zs1 , 'T', 1., zs2, 'T', 1., zs12, 'F', 1. ) |
|---|
| 424 | |
|---|
| 425 | ! Ice internal stresses (Appendix C of Hunke and Dukowicz, 2002) |
|---|
| 426 | DO jj = k_j1+1, k_jpj-1 |
|---|
| 427 | DO ji = fs_2, fs_jpim1 |
|---|
| 428 | !- contribution of zs1, zs2 and zs12 to zf1 |
|---|
| 429 | zf1(ji,jj) = 0.5 * ( ( zs1(ji+1,jj) - zs1(ji,jj) ) * e2u(ji,jj) & |
|---|
| 430 | & + ( zs2(ji+1,jj) * e2t(ji+1,jj)**2 - zs2(ji,jj) * e2t(ji,jj)**2 ) * r1_e2u(ji,jj) & |
|---|
| 431 | & + 2.0 * ( zs12(ji,jj) * e1f(ji,jj)**2 - zs12(ji,jj-1) * e1f(ji,jj-1)**2 ) * r1_e1u(ji,jj) & |
|---|
| 432 | & ) * r1_e12u(ji,jj) |
|---|
| 433 | ! contribution of zs1, zs2 and zs12 to zf2 |
|---|
| 434 | zf2(ji,jj) = 0.5 * ( ( zs1(ji,jj+1) - zs1(ji,jj) ) * e1v(ji,jj) & |
|---|
| 435 | & - ( zs2(ji,jj+1) * e1t(ji,jj+1)**2 - zs2(ji,jj) * e1t(ji,jj)**2 ) * r1_e1v(ji,jj) & |
|---|
| 436 | & + 2.0 * ( zs12(ji,jj) * e2f(ji,jj)**2 - zs12(ji-1,jj) * e2f(ji-1,jj)**2 ) * r1_e2v(ji,jj) & |
|---|
| 437 | & ) * r1_e12v(ji,jj) |
|---|
| 438 | END DO |
|---|
| 439 | END DO |
|---|
| 440 | ! |
|---|
| 441 | ! Computation of ice velocity |
|---|
| 442 | ! |
|---|
| 443 | ! Both the Coriolis term and the ice-ocean drag are solved semi-implicitly. |
|---|
| 444 | ! |
|---|
| 445 | IF (MOD(jter,2).eq.0) THEN |
|---|
| 446 | |
|---|
| 447 | DO jj = k_j1+1, k_jpj-1 |
|---|
| 448 | DO ji = fs_2, fs_jpim1 |
|---|
| 449 | rswitch = ( 1.0 - MAX( 0._wp, SIGN( 1._wp, -zmass1(ji,jj) ) ) ) * umask(ji,jj,1) |
|---|
| 450 | z0 = zmass1(ji,jj) * z1_dtevp |
|---|
| 451 | |
|---|
| 452 | ! SB modif because ocean has no slip boundary condition |
|---|
| 453 | zv_ice1 = 0.5 * ( ( v_ice(ji ,jj) + v_ice(ji ,jj-1) ) * e1t(ji ,jj) & |
|---|
| 454 | & + ( v_ice(ji+1,jj) + v_ice(ji+1,jj-1) ) * e1t(ji+1,jj) ) & |
|---|
| 455 | & / ( e1t(ji+1,jj) + e1t(ji,jj) ) * umask(ji,jj,1) |
|---|
| 456 | za = rhoco * SQRT( ( u_ice(ji,jj) - u_oce(ji,jj) )**2 + & |
|---|
| 457 | & ( zv_ice1 - v_oce1(ji,jj) )**2 ) * ( 1.0 - zfrld1(ji,jj) ) |
|---|
| 458 | zr = z0 * u_ice(ji,jj) + zf1(ji,jj) + za1ct(ji,jj) + za * u_oce(ji,jj) |
|---|
| 459 | zcca = z0 + za |
|---|
| 460 | zccb = zcorl1(ji,jj) |
|---|
| 461 | u_ice(ji,jj) = ( zr + zccb * zv_ice1 ) / ( zcca + zepsi ) * rswitch |
|---|
| 462 | END DO |
|---|
| 463 | END DO |
|---|
| 464 | |
|---|
| 465 | CALL lbc_lnk( u_ice(:,:), 'U', -1. ) |
|---|
| 466 | #if defined key_agrif && defined key_lim2 |
|---|
| 467 | CALL agrif_rhg_lim2( jter, nn_nevp, 'U' ) |
|---|
| 468 | #endif |
|---|
| 469 | #if defined key_agrif && defined key_lim3 |
|---|
| 470 | CALL agrif_interp_lim3( 'U' ) |
|---|
| 471 | #endif |
|---|
| 472 | #if defined key_bdy |
|---|
| 473 | CALL bdy_ice_lim_dyn( 'U' ) |
|---|
| 474 | #endif |
|---|
| 475 | |
|---|
| 476 | DO jj = k_j1+1, k_jpj-1 |
|---|
| 477 | DO ji = fs_2, fs_jpim1 |
|---|
| 478 | |
|---|
| 479 | rswitch = ( 1.0 - MAX( 0._wp, SIGN( 1._wp, -zmass2(ji,jj) ) ) ) * vmask(ji,jj,1) |
|---|
| 480 | z0 = zmass2(ji,jj) * z1_dtevp |
|---|
| 481 | ! SB modif because ocean has no slip boundary condition |
|---|
| 482 | zu_ice2 = 0.5 * ( ( u_ice(ji,jj ) + u_ice(ji-1,jj ) ) * e2t(ji,jj) & |
|---|
| 483 | & + ( u_ice(ji,jj+1) + u_ice(ji-1,jj+1) ) * e2t(ji,jj+1) ) & |
|---|
| 484 | & / ( e2t(ji,jj+1) + e2t(ji,jj) ) * vmask(ji,jj,1) |
|---|
| 485 | za = rhoco * SQRT( ( zu_ice2 - u_oce2(ji,jj) )**2 + & |
|---|
| 486 | & ( v_ice(ji,jj) - v_oce(ji,jj))**2 ) * ( 1.0 - zfrld2(ji,jj) ) |
|---|
| 487 | zr = z0 * v_ice(ji,jj) + zf2(ji,jj) + za2ct(ji,jj) + za * v_oce(ji,jj) |
|---|
| 488 | zcca = z0 + za |
|---|
| 489 | zccb = zcorl2(ji,jj) |
|---|
| 490 | v_ice(ji,jj) = ( zr - zccb * zu_ice2 ) / ( zcca + zepsi ) * rswitch |
|---|
| 491 | END DO |
|---|
| 492 | END DO |
|---|
| 493 | |
|---|
| 494 | CALL lbc_lnk( v_ice(:,:), 'V', -1. ) |
|---|
| 495 | #if defined key_agrif && defined key_lim2 |
|---|
| 496 | CALL agrif_rhg_lim2( jter, nn_nevp, 'V' ) |
|---|
| 497 | #endif |
|---|
| 498 | #if defined key_agrif && defined key_lim3 |
|---|
| 499 | CALL agrif_interp_lim3( 'V' ) |
|---|
| 500 | #endif |
|---|
| 501 | #if defined key_bdy |
|---|
| 502 | CALL bdy_ice_lim_dyn( 'V' ) |
|---|
| 503 | #endif |
|---|
| 504 | |
|---|
| 505 | ELSE |
|---|
| 506 | DO jj = k_j1+1, k_jpj-1 |
|---|
| 507 | DO ji = fs_2, fs_jpim1 |
|---|
| 508 | rswitch = ( 1.0 - MAX( 0._wp, SIGN( 1._wp, -zmass2(ji,jj) ) ) ) * vmask(ji,jj,1) |
|---|
| 509 | z0 = zmass2(ji,jj) * z1_dtevp |
|---|
| 510 | ! SB modif because ocean has no slip boundary condition |
|---|
| 511 | zu_ice2 = 0.5 * ( ( u_ice(ji,jj ) + u_ice(ji-1,jj ) ) * e2t(ji,jj) & |
|---|
| 512 | & +( u_ice(ji,jj+1) + u_ice(ji-1,jj+1) ) * e2t(ji,jj+1) ) & |
|---|
| 513 | & / ( e2t(ji,jj+1) + e2t(ji,jj) ) * vmask(ji,jj,1) |
|---|
| 514 | |
|---|
| 515 | za = rhoco * SQRT( ( zu_ice2 - u_oce2(ji,jj) )**2 + & |
|---|
| 516 | & ( v_ice(ji,jj) - v_oce(ji,jj) )**2 ) * ( 1.0 - zfrld2(ji,jj) ) |
|---|
| 517 | zr = z0 * v_ice(ji,jj) + zf2(ji,jj) + za2ct(ji,jj) + za * v_oce(ji,jj) |
|---|
| 518 | zcca = z0 + za |
|---|
| 519 | zccb = zcorl2(ji,jj) |
|---|
| 520 | v_ice(ji,jj) = ( zr - zccb * zu_ice2 ) / ( zcca + zepsi ) * rswitch |
|---|
| 521 | END DO |
|---|
| 522 | END DO |
|---|
| 523 | |
|---|
| 524 | CALL lbc_lnk( v_ice(:,:), 'V', -1. ) |
|---|
| 525 | #if defined key_agrif && defined key_lim2 |
|---|
| 526 | CALL agrif_rhg_lim2( jter, nn_nevp, 'V' ) |
|---|
| 527 | #endif |
|---|
| 528 | #if defined key_agrif && defined key_lim3 |
|---|
| 529 | CALL agrif_interp_lim3( 'V' ) |
|---|
| 530 | #endif |
|---|
| 531 | #if defined key_bdy |
|---|
| 532 | CALL bdy_ice_lim_dyn( 'V' ) |
|---|
| 533 | #endif |
|---|
| 534 | |
|---|
| 535 | DO jj = k_j1+1, k_jpj-1 |
|---|
| 536 | DO ji = fs_2, fs_jpim1 |
|---|
| 537 | rswitch = ( 1.0 - MAX( 0._wp, SIGN( 1._wp, -zmass1(ji,jj) ) ) ) * umask(ji,jj,1) |
|---|
| 538 | z0 = zmass1(ji,jj) * z1_dtevp |
|---|
| 539 | zv_ice1 = 0.5 * ( ( v_ice(ji ,jj) + v_ice(ji ,jj-1) ) * e1t(ji,jj) & |
|---|
| 540 | & + ( v_ice(ji+1,jj) + v_ice(ji+1,jj-1) ) * e1t(ji+1,jj) ) & |
|---|
| 541 | & / ( e1t(ji+1,jj) + e1t(ji,jj) ) * umask(ji,jj,1) |
|---|
| 542 | |
|---|
| 543 | za = rhoco * SQRT( ( u_ice(ji,jj) - u_oce(ji,jj) )**2 + & |
|---|
| 544 | & ( zv_ice1 - v_oce1(ji,jj) )**2 ) * ( 1.0 - zfrld1(ji,jj) ) |
|---|
| 545 | zr = z0 * u_ice(ji,jj) + zf1(ji,jj) + za1ct(ji,jj) + za * u_oce(ji,jj) |
|---|
| 546 | zcca = z0 + za |
|---|
| 547 | zccb = zcorl1(ji,jj) |
|---|
| 548 | u_ice(ji,jj) = ( zr + zccb * zv_ice1 ) / ( zcca + zepsi ) * rswitch |
|---|
| 549 | END DO |
|---|
| 550 | END DO |
|---|
| 551 | |
|---|
| 552 | CALL lbc_lnk( u_ice(:,:), 'U', -1. ) |
|---|
| 553 | #if defined key_agrif && defined key_lim2 |
|---|
| 554 | CALL agrif_rhg_lim2( jter, nn_nevp, 'U' ) |
|---|
| 555 | #endif |
|---|
| 556 | #if defined key_agrif && defined key_lim3 |
|---|
| 557 | CALL agrif_interp_lim3( 'U' ) |
|---|
| 558 | #endif |
|---|
| 559 | #if defined key_bdy |
|---|
| 560 | CALL bdy_ice_lim_dyn( 'U' ) |
|---|
| 561 | #endif |
|---|
| 562 | |
|---|
| 563 | ENDIF |
|---|
| 564 | |
|---|
| 565 | IF(ln_ctl) THEN |
|---|
| 566 | !--- Convergence test. |
|---|
| 567 | DO jj = k_j1+1 , k_jpj-1 |
|---|
| 568 | zresr(:,jj) = MAX( ABS( u_ice(:,jj) - zu_ice(:,jj) ), ABS( v_ice(:,jj) - zv_ice(:,jj) ) ) |
|---|
| 569 | END DO |
|---|
| 570 | zresm = MAXVAL( zresr( 1:jpi, k_j1+1:k_jpj-1 ) ) |
|---|
| 571 | IF( lk_mpp ) CALL mpp_max( zresm ) ! max over the global domain |
|---|
| 572 | ENDIF |
|---|
| 573 | |
|---|
| 574 | ! ! ==================== ! |
|---|
| 575 | END DO ! end loop over jter ! |
|---|
| 576 | ! ! ==================== ! |
|---|
| 577 | ! |
|---|
| 578 | !------------------------------------------------------------------------------! |
|---|
| 579 | ! 4) Prevent ice velocities when the ice is thin |
|---|
| 580 | !------------------------------------------------------------------------------! |
|---|
| 581 | ! If the ice volume is below zvmin then ice velocity should equal the |
|---|
| 582 | ! ocean velocity. This prevents high velocity when ice is thin |
|---|
| 583 | DO jj = k_j1+1, k_jpj-1 |
|---|
| 584 | DO ji = fs_2, fs_jpim1 |
|---|
| 585 | IF ( vt_i(ji,jj) <= zvmin ) THEN |
|---|
| 586 | u_ice(ji,jj) = u_oce(ji,jj) |
|---|
| 587 | v_ice(ji,jj) = v_oce(ji,jj) |
|---|
| 588 | ENDIF |
|---|
| 589 | END DO |
|---|
| 590 | END DO |
|---|
| 591 | |
|---|
| 592 | CALL lbc_lnk_multi( u_ice(:,:), 'U', -1., v_ice(:,:), 'V', -1. ) |
|---|
| 593 | |
|---|
| 594 | #if defined key_agrif && defined key_lim2 |
|---|
| 595 | CALL agrif_rhg_lim2( nn_nevp , nn_nevp, 'U' ) |
|---|
| 596 | CALL agrif_rhg_lim2( nn_nevp , nn_nevp, 'V' ) |
|---|
| 597 | #endif |
|---|
| 598 | #if defined key_agrif && defined key_lim3 |
|---|
| 599 | CALL agrif_interp_lim3( 'U' ) |
|---|
| 600 | CALL agrif_interp_lim3( 'V' ) |
|---|
| 601 | #endif |
|---|
| 602 | #if defined key_bdy |
|---|
| 603 | CALL bdy_ice_lim_dyn( 'U' ) |
|---|
| 604 | CALL bdy_ice_lim_dyn( 'V' ) |
|---|
| 605 | #endif |
|---|
| 606 | |
|---|
| 607 | DO jj = k_j1+1, k_jpj-1 |
|---|
| 608 | DO ji = fs_2, fs_jpim1 |
|---|
| 609 | IF ( vt_i(ji,jj) <= zvmin ) THEN |
|---|
| 610 | v_ice1(ji,jj) = 0.5_wp * ( ( v_ice(ji ,jj) + v_ice(ji, jj-1) ) * e1t(ji+1,jj) & |
|---|
| 611 | & + ( v_ice(ji+1,jj) + v_ice(ji+1,jj-1) ) * e1t(ji ,jj) ) & |
|---|
| 612 | & / ( e1t(ji+1,jj) + e1t(ji,jj) ) * umask(ji,jj,1) |
|---|
| 613 | |
|---|
| 614 | u_ice2(ji,jj) = 0.5_wp * ( ( u_ice(ji,jj ) + u_ice(ji-1,jj ) ) * e2t(ji,jj+1) & |
|---|
| 615 | & + ( u_ice(ji,jj+1) + u_ice(ji-1,jj+1) ) * e2t(ji,jj ) ) & |
|---|
| 616 | & / ( e2t(ji,jj+1) + e2t(ji,jj) ) * vmask(ji,jj,1) |
|---|
| 617 | ENDIF |
|---|
| 618 | END DO |
|---|
| 619 | END DO |
|---|
| 620 | |
|---|
| 621 | CALL lbc_lnk_multi( u_ice2(:,:), 'V', -1., v_ice1(:,:), 'U', -1. ) |
|---|
| 622 | |
|---|
| 623 | ! Recompute delta, shear and div, inputs for mechanical redistribution |
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| 624 | DO jj = k_j1+1, k_jpj-1 |
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| 625 | DO ji = fs_2, jpim1 !RB bug no vect opt due to zmask |
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| 626 | !- divu_i(:,:), zdt(:,:): divergence and tension at centre |
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| 627 | !- zds(:,:): shear on northeast corner of grid cells |
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| 628 | IF ( vt_i(ji,jj) <= zvmin ) THEN |
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| 629 | |
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| 630 | divu_i(ji,jj) = ( e2u(ji,jj) * u_ice(ji,jj) - e2u(ji-1,jj ) * u_ice(ji-1,jj ) & |
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| 631 | & + e1v(ji,jj) * v_ice(ji,jj) - e1v(ji ,jj-1) * v_ice(ji ,jj-1) & |
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| 632 | & ) * r1_e12t(ji,jj) |
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| 633 | |
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| 634 | 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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| 635 | & -( 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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| 636 | & ) * r1_e12t(ji,jj) |
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| 637 | ! |
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| 638 | ! SB modif because ocean has no slip boundary condition |
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| 639 | 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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| 640 | & +( 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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| 641 | & ) * r1_e12f(ji,jj) * ( 2.0 - fmask(ji,jj,1) ) & |
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| 642 | & * zmask(ji,jj) * zmask(ji,jj+1) * zmask(ji+1,jj) * zmask(ji+1,jj+1) |
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| 643 | |
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| 644 | zdst = ( e2u(ji,jj) * v_ice1(ji,jj) - e2u(ji-1,jj ) * v_ice1(ji-1,jj ) & |
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| 645 | & + e1v(ji,jj) * u_ice2(ji,jj) - e1v(ji ,jj-1) * u_ice2(ji ,jj-1) ) * r1_e12t(ji,jj) |
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| 646 | |
|---|
| 647 | delta = SQRT( divu_i(ji,jj)**2 + ( zdt(ji,jj)**2 + zdst**2 ) * usecc2 ) |
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| 648 | delta_i(ji,jj) = delta + rn_creepl |
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| 649 | |
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| 650 | ENDIF |
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| 651 | END DO |
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| 652 | END DO |
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| 653 | ! |
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| 654 | !------------------------------------------------------------------------------! |
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| 655 | ! 5) Store stress tensor and its invariants |
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| 656 | !------------------------------------------------------------------------------! |
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| 657 | ! * Invariants of the stress tensor are required for limitd_me |
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| 658 | ! (accelerates convergence and improves stability) |
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| 659 | DO jj = k_j1+1, k_jpj-1 |
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| 660 | DO ji = fs_2, fs_jpim1 |
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| 661 | zdst = ( e2u(ji,jj) * v_ice1(ji,jj) - e2u( ji-1, jj ) * v_ice1(ji-1,jj) & |
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| 662 | & + e1v(ji,jj) * u_ice2(ji,jj) - e1v( ji , jj-1 ) * u_ice2(ji,jj-1) ) * r1_e12t(ji,jj) |
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| 663 | shear_i(ji,jj) = SQRT( zdt(ji,jj) * zdt(ji,jj) + zdst * zdst ) |
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| 664 | END DO |
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| 665 | END DO |
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| 666 | |
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| 667 | ! Lateral boundary condition |
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| 668 | CALL lbc_lnk_multi( divu_i (:,:), 'T', 1., delta_i(:,:), 'T', 1., shear_i(:,:), 'T', 1. ) |
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| 669 | |
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| 670 | ! * Store the stress tensor for the next time step |
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| 671 | stress1_i (:,:) = zs1 (:,:) |
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| 672 | stress2_i (:,:) = zs2 (:,:) |
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| 673 | stress12_i(:,:) = zs12(:,:) |
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| 674 | |
|---|
| 675 | ! |
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| 676 | !------------------------------------------------------------------------------! |
|---|
| 677 | ! 6) Control prints of residual and charge ellipse |
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| 678 | !------------------------------------------------------------------------------! |
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| 679 | ! |
|---|
| 680 | ! print the residual for convergence |
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| 681 | IF(ln_ctl) THEN |
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| 682 | WRITE(charout,FMT="('lim_rhg : res =',D23.16, ' iter =',I4)") zresm, jter |
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| 683 | CALL prt_ctl_info(charout) |
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| 684 | CALL prt_ctl(tab2d_1=u_ice, clinfo1=' lim_rhg : u_ice :', tab2d_2=v_ice, clinfo2=' v_ice :') |
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| 685 | ENDIF |
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| 686 | |
|---|
| 687 | ! print charge ellipse |
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| 688 | ! This can be desactivated once the user is sure that the stress state |
|---|
| 689 | ! lie on the charge ellipse. See Bouillon et al. 08 for more details |
|---|
| 690 | IF(ln_ctl) THEN |
|---|
| 691 | CALL prt_ctl_info('lim_rhg : numit :',ivar1=numit) |
|---|
| 692 | CALL prt_ctl_info('lim_rhg : nwrite :',ivar1=nwrite) |
|---|
| 693 | CALL prt_ctl_info('lim_rhg : MOD :',ivar1=MOD(numit,nwrite)) |
|---|
| 694 | IF( MOD(numit,nwrite) .EQ. 0 ) THEN |
|---|
| 695 | WRITE(charout,FMT="('lim_rhg :', I4, I6, I1, I1, A10)") 1000, numit, 0, 0, ' ch. ell. ' |
|---|
| 696 | CALL prt_ctl_info(charout) |
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| 697 | DO jj = k_j1+1, k_jpj-1 |
|---|
| 698 | DO ji = 2, jpim1 |
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| 699 | IF (zpresh(ji,jj) > 1.0) THEN |
|---|
| 700 | sigma1 = ( zs1(ji,jj) + (zs2(ji,jj)**2 + 4*zs12(ji,jj)**2 )**0.5 ) / ( 2*zpresh(ji,jj) ) |
|---|
| 701 | sigma2 = ( zs1(ji,jj) - (zs2(ji,jj)**2 + 4*zs12(ji,jj)**2 )**0.5 ) / ( 2*zpresh(ji,jj) ) |
|---|
| 702 | WRITE(charout,FMT="('lim_rhg :', I4, I4, D23.16, D23.16, D23.16, D23.16, A10)") |
|---|
| 703 | CALL prt_ctl_info(charout) |
|---|
| 704 | ENDIF |
|---|
| 705 | END DO |
|---|
| 706 | END DO |
|---|
| 707 | WRITE(charout,FMT="('lim_rhg :', I4, I6, I1, I1, A10)") 2000, numit, 0, 0, ' ch. ell. ' |
|---|
| 708 | CALL prt_ctl_info(charout) |
|---|
| 709 | ENDIF |
|---|
| 710 | ENDIF |
|---|
| 711 | ! |
|---|
| 712 | CALL wrk_dealloc( jpi,jpj, zpresh, zfrld1, zmass1, zcorl1, za1ct , zpreshc, zfrld2, zmass2, zcorl2, za2ct ) |
|---|
| 713 | CALL wrk_dealloc( jpi,jpj, u_oce2, u_ice2, v_oce1 , v_ice1 , zmask ) |
|---|
| 714 | CALL wrk_dealloc( jpi,jpj, zf1 , zu_ice, zf2 , zv_ice , zdt , zds ) |
|---|
| 715 | CALL wrk_dealloc( jpi,jpj, zs1 , zs2 , zs12 , zresr , zpice ) |
|---|
| 716 | |
|---|
| 717 | END SUBROUTINE lim_rhg |
|---|
| 718 | |
|---|
| 719 | #else |
|---|
| 720 | !!---------------------------------------------------------------------- |
|---|
| 721 | !! Default option Dummy module NO LIM sea-ice model |
|---|
| 722 | !!---------------------------------------------------------------------- |
|---|
| 723 | CONTAINS |
|---|
| 724 | SUBROUTINE lim_rhg( k1 , k2 ) ! Dummy routine |
|---|
| 725 | WRITE(*,*) 'lim_rhg: You should not have seen this print! error?', k1, k2 |
|---|
| 726 | END SUBROUTINE lim_rhg |
|---|
| 727 | #endif |
|---|
| 728 | |
|---|
| 729 | !!============================================================================== |
|---|
| 730 | END MODULE limrhg |
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