1 | !> @file diffusion_w.f90 |
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2 | !------------------------------------------------------------------------------! |
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3 | ! This file is part of the PALM model system. |
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4 | ! |
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5 | ! PALM is free software: you can redistribute it and/or modify it under the |
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6 | ! terms of the GNU General Public License as published by the Free Software |
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7 | ! Foundation, either version 3 of the License, or (at your option) any later |
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8 | ! version. |
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9 | ! |
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10 | ! PALM is distributed in the hope that it will be useful, but WITHOUT ANY |
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11 | ! WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR |
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12 | ! A PARTICULAR PURPOSE. See the GNU General Public License for more details. |
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13 | ! |
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14 | ! You should have received a copy of the GNU General Public License along with |
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15 | ! PALM. If not, see <http://www.gnu.org/licenses/>. |
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16 | ! |
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17 | ! Copyright 1997-2020 Leibniz Universitaet Hannover |
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18 | !------------------------------------------------------------------------------! |
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19 | ! |
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20 | ! Current revisions: |
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21 | ! ----------------- |
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22 | ! |
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23 | ! |
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24 | ! Former revisions: |
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25 | ! ----------------- |
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26 | ! $Id: diffusion_w.f90 4360 2020-01-07 11:25:50Z maronga $ |
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27 | ! Introduction of wall_flags_total_0, which currently sets bits based on static |
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28 | ! topography information used in wall_flags_static_0 |
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29 | ! |
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30 | ! 4329 2019-12-10 15:46:36Z motisi |
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31 | ! Renamed wall_flags_0 to wall_flags_static_0 |
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32 | ! |
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33 | ! 4182 2019-08-22 15:20:23Z scharf |
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34 | ! Corrected "Former revisions" section |
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35 | ! |
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36 | ! 3655 2019-01-07 16:51:22Z knoop |
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37 | ! OpenACC port for SPEC |
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38 | ! |
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39 | ! Revision 1.1 1997/09/12 06:24:11 raasch |
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40 | ! Initial revision |
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41 | ! |
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42 | ! |
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43 | ! Description: |
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44 | ! ------------ |
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45 | !> Diffusion term of the w-component |
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46 | !------------------------------------------------------------------------------! |
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47 | MODULE diffusion_w_mod |
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48 | |
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49 | |
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50 | PRIVATE |
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51 | PUBLIC diffusion_w |
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52 | |
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53 | INTERFACE diffusion_w |
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54 | MODULE PROCEDURE diffusion_w |
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55 | MODULE PROCEDURE diffusion_w_ij |
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56 | END INTERFACE diffusion_w |
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57 | |
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58 | CONTAINS |
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59 | |
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60 | |
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61 | !------------------------------------------------------------------------------! |
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62 | ! Description: |
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63 | ! ------------ |
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64 | !> Call for all grid points |
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65 | !------------------------------------------------------------------------------! |
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66 | SUBROUTINE diffusion_w |
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67 | |
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68 | USE arrays_3d, & |
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69 | ONLY : ddzu, ddzw, km, tend, u, v, w, drho_air_zw, rho_air |
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70 | |
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71 | USE grid_variables, & |
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72 | ONLY : ddx, ddy |
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73 | |
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74 | USE indices, & |
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75 | ONLY : nxl, nxr, nyn, nys, nzb, nzt, wall_flags_total_0 |
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76 | |
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77 | USE kinds |
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78 | |
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79 | USE surface_mod, & |
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80 | ONLY : surf_def_v, surf_lsm_v, surf_usm_v |
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81 | |
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82 | IMPLICIT NONE |
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83 | |
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84 | INTEGER(iwp) :: i !< running index x direction |
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85 | INTEGER(iwp) :: j !< running index y direction |
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86 | INTEGER(iwp) :: k !< running index z direction |
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87 | INTEGER(iwp) :: l !< running index of surface type, south- or north-facing wall |
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88 | INTEGER(iwp) :: m !< running index surface elements |
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89 | INTEGER(iwp) :: surf_e !< End index of surface elements at (j,i)-gridpoint |
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90 | INTEGER(iwp) :: surf_s !< Start index of surface elements at (j,i)-gridpoint |
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91 | |
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92 | REAL(wp) :: flag !< flag to mask topography grid points |
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93 | REAL(wp) :: kmxm !< diffusion coefficient on leftward side of the w-gridbox - interpolated onto xu-y grid |
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94 | REAL(wp) :: kmxp !<diffusion coefficient on rightward side of the w-gridbox - interpolated onto xu-y grid |
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95 | REAL(wp) :: kmym !< diffusion coefficient on southward side of the w-gridbox - interpolated onto x-yv grid |
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96 | REAL(wp) :: kmyp !< diffusion coefficient on northward side of the w-gridbox - interpolated onto x-yv grid |
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97 | REAL(wp) :: mask_west !< flag to mask vertical wall west of the grid point |
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98 | REAL(wp) :: mask_east !< flag to mask vertical wall east of the grid point |
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99 | REAL(wp) :: mask_south !< flag to mask vertical wall south of the grid point |
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100 | REAL(wp) :: mask_north !< flag to mask vertical wall north of the grid point |
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101 | |
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102 | |
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103 | |
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104 | !$ACC PARALLEL LOOP COLLAPSE(2) PRIVATE(i, j, k, l, m) & |
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105 | !$ACC PRIVATE(surf_e, surf_s, flag, kmxm, kmxp, kmym, kmyp) & |
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106 | !$ACC PRIVATE(mask_west, mask_east, mask_south, mask_north) & |
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107 | !$ACC PRESENT(wall_flags_total_0, km) & |
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108 | !$ACC PRESENT(u, v, w) & |
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109 | !$ACC PRESENT(ddzu, ddzw, rho_air, drho_air_zw) & |
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110 | !$ACC PRESENT(surf_def_v(0:3)) & |
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111 | !$ACC PRESENT(surf_lsm_v(0:3)) & |
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112 | !$ACC PRESENT(surf_usm_v(0:3)) & |
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113 | !$ACC PRESENT(tend) |
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114 | DO i = nxl, nxr |
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115 | DO j = nys, nyn |
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116 | DO k = nzb+1, nzt-1 |
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117 | ! |
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118 | !-- Predetermine flag to mask topography and wall-bounded grid points. |
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119 | flag = MERGE( 1.0_wp, 0.0_wp, & |
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120 | BTEST( wall_flags_total_0(k,j,i), 3 ) ) |
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121 | mask_east = MERGE( 1.0_wp, 0.0_wp, & |
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122 | BTEST( wall_flags_total_0(k,j,i+1), 3 ) ) |
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123 | mask_west = MERGE( 1.0_wp, 0.0_wp, & |
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124 | BTEST( wall_flags_total_0(k,j,i-1), 3 ) ) |
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125 | mask_south = MERGE( 1.0_wp, 0.0_wp, & |
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126 | BTEST( wall_flags_total_0(k,j-1,i), 3 ) ) |
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127 | mask_north = MERGE( 1.0_wp, 0.0_wp, & |
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128 | BTEST( wall_flags_total_0(k,j+1,i), 3 ) ) |
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129 | ! |
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130 | !-- Interpolate eddy diffusivities on staggered gridpoints |
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131 | kmxp = 0.25_wp * ( km(k,j,i) + km(k,j,i+1) + & |
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132 | km(k+1,j,i) + km(k+1,j,i+1) ) |
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133 | kmxm = 0.25_wp * ( km(k,j,i) + km(k,j,i-1) + & |
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134 | km(k+1,j,i) + km(k+1,j,i-1) ) |
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135 | kmyp = 0.25_wp * ( km(k,j,i) + km(k+1,j,i) + & |
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136 | km(k,j+1,i) + km(k+1,j+1,i) ) |
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137 | kmym = 0.25_wp * ( km(k,j,i) + km(k+1,j,i) + & |
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138 | km(k,j-1,i) + km(k+1,j-1,i) ) |
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139 | |
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140 | tend(k,j,i) = tend(k,j,i) & |
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141 | + ( mask_east * kmxp * ( & |
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142 | ( w(k,j,i+1) - w(k,j,i) ) * ddx & |
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143 | + ( u(k+1,j,i+1) - u(k,j,i+1) ) * ddzu(k+1) & |
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144 | ) & |
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145 | - mask_west * kmxm * ( & |
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146 | ( w(k,j,i) - w(k,j,i-1) ) * ddx & |
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147 | + ( u(k+1,j,i) - u(k,j,i) ) * ddzu(k+1) & |
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148 | ) & |
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149 | ) * ddx * flag & |
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150 | + ( mask_north * kmyp * ( & |
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151 | ( w(k,j+1,i) - w(k,j,i) ) * ddy & |
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152 | + ( v(k+1,j+1,i) - v(k,j+1,i) ) * ddzu(k+1) & |
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153 | ) & |
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154 | - mask_south * kmym * ( & |
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155 | ( w(k,j,i) - w(k,j-1,i) ) * ddy & |
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156 | + ( v(k+1,j,i) - v(k,j,i) ) * ddzu(k+1) & |
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157 | ) & |
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158 | ) * ddy * flag & |
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159 | + 2.0_wp * ( & |
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160 | km(k+1,j,i) * ( w(k+1,j,i) - w(k,j,i) ) * ddzw(k+1) & |
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161 | * rho_air(k+1) & |
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162 | - km(k,j,i) * ( w(k,j,i) - w(k-1,j,i) ) * ddzw(k) & |
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163 | * rho_air(k) & |
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164 | ) * ddzu(k+1) * drho_air_zw(k) * flag |
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165 | ENDDO |
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166 | |
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167 | ! |
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168 | !-- Add horizontal momentum flux v'w' at north- (l=0) and south-facing (l=1) |
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169 | !-- surfaces. Note, in the the flat case, loops won't be entered as |
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170 | !-- start_index > end_index. Furtermore, note, no vertical natural surfaces |
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171 | !-- so far. |
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172 | !-- Default-type surfaces |
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173 | DO l = 0, 1 |
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174 | surf_s = surf_def_v(l)%start_index(j,i) |
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175 | surf_e = surf_def_v(l)%end_index(j,i) |
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176 | DO m = surf_s, surf_e |
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177 | k = surf_def_v(l)%k(m) |
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178 | tend(k,j,i) = tend(k,j,i) + & |
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179 | surf_def_v(l)%mom_flux_w(m) * ddy |
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180 | ENDDO |
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181 | ENDDO |
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182 | ! |
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183 | !-- Natural-type surfaces |
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184 | DO l = 0, 1 |
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185 | surf_s = surf_lsm_v(l)%start_index(j,i) |
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186 | surf_e = surf_lsm_v(l)%end_index(j,i) |
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187 | DO m = surf_s, surf_e |
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188 | k = surf_lsm_v(l)%k(m) |
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189 | tend(k,j,i) = tend(k,j,i) + & |
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190 | surf_lsm_v(l)%mom_flux_w(m) * ddy |
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191 | ENDDO |
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192 | ENDDO |
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193 | ! |
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194 | !-- Urban-type surfaces |
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195 | DO l = 0, 1 |
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196 | surf_s = surf_usm_v(l)%start_index(j,i) |
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197 | surf_e = surf_usm_v(l)%end_index(j,i) |
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198 | DO m = surf_s, surf_e |
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199 | k = surf_usm_v(l)%k(m) |
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200 | tend(k,j,i) = tend(k,j,i) + & |
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201 | surf_usm_v(l)%mom_flux_w(m) * ddy |
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202 | ENDDO |
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203 | ENDDO |
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204 | ! |
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205 | !-- Add horizontal momentum flux u'w' at east- (l=2) and west-facing (l=3) |
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206 | !-- surface. |
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207 | !-- Default-type surfaces |
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208 | DO l = 2, 3 |
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209 | surf_s = surf_def_v(l)%start_index(j,i) |
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210 | surf_e = surf_def_v(l)%end_index(j,i) |
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211 | DO m = surf_s, surf_e |
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212 | k = surf_def_v(l)%k(m) |
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213 | tend(k,j,i) = tend(k,j,i) + & |
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214 | surf_def_v(l)%mom_flux_w(m) * ddx |
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215 | ENDDO |
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216 | ENDDO |
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217 | ! |
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218 | !-- Natural-type surfaces |
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219 | DO l = 2, 3 |
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220 | surf_s = surf_lsm_v(l)%start_index(j,i) |
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221 | surf_e = surf_lsm_v(l)%end_index(j,i) |
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222 | DO m = surf_s, surf_e |
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223 | k = surf_lsm_v(l)%k(m) |
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224 | tend(k,j,i) = tend(k,j,i) + & |
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225 | surf_lsm_v(l)%mom_flux_w(m) * ddx |
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226 | ENDDO |
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227 | ENDDO |
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228 | ! |
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229 | !-- Urban-type surfaces |
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230 | DO l = 2, 3 |
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231 | surf_s = surf_usm_v(l)%start_index(j,i) |
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232 | surf_e = surf_usm_v(l)%end_index(j,i) |
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233 | DO m = surf_s, surf_e |
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234 | k = surf_usm_v(l)%k(m) |
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235 | tend(k,j,i) = tend(k,j,i) + & |
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236 | surf_usm_v(l)%mom_flux_w(m) * ddx |
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237 | ENDDO |
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238 | ENDDO |
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239 | |
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240 | ENDDO |
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241 | ENDDO |
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242 | |
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243 | END SUBROUTINE diffusion_w |
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244 | |
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245 | |
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246 | !------------------------------------------------------------------------------! |
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247 | ! Description: |
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248 | ! ------------ |
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249 | !> Call for grid point i,j |
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250 | !------------------------------------------------------------------------------! |
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251 | SUBROUTINE diffusion_w_ij( i, j ) |
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252 | |
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253 | USE arrays_3d, & |
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254 | ONLY : ddzu, ddzw, km, tend, u, v, w, drho_air_zw, rho_air |
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255 | |
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256 | USE grid_variables, & |
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257 | ONLY : ddx, ddy |
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258 | |
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259 | USE indices, & |
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260 | ONLY : nzb, nzt, wall_flags_total_0 |
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261 | |
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262 | USE kinds |
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263 | |
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264 | USE surface_mod, & |
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265 | ONLY : surf_def_v, surf_lsm_v, surf_usm_v |
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266 | |
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267 | IMPLICIT NONE |
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268 | |
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269 | |
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270 | INTEGER(iwp) :: i !< running index x direction |
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271 | INTEGER(iwp) :: j !< running index y direction |
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272 | INTEGER(iwp) :: k !< running index z direction |
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273 | INTEGER(iwp) :: l !< running index of surface type, south- or north-facing wall |
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274 | INTEGER(iwp) :: m !< running index surface elements |
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275 | INTEGER(iwp) :: surf_e !< End index of surface elements at (j,i)-gridpoint |
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276 | INTEGER(iwp) :: surf_s !< Start index of surface elements at (j,i)-gridpoint |
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277 | |
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278 | REAL(wp) :: flag !< flag to mask topography grid points |
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279 | REAL(wp) :: kmxm !< diffusion coefficient on leftward side of the w-gridbox - interpolated onto xu-y grid |
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280 | REAL(wp) :: kmxp !< diffusion coefficient on rightward side of the w-gridbox - interpolated onto xu-y grid |
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281 | REAL(wp) :: kmym !< diffusion coefficient on southward side of the w-gridbox - interpolated onto x-yv grid |
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282 | REAL(wp) :: kmyp !< diffusion coefficient on northward side of the w-gridbox - interpolated onto x-yv grid |
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283 | REAL(wp) :: mask_west !< flag to mask vertical wall west of the grid point |
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284 | REAL(wp) :: mask_east !< flag to mask vertical wall east of the grid point |
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285 | REAL(wp) :: mask_south !< flag to mask vertical wall south of the grid point |
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286 | REAL(wp) :: mask_north !< flag to mask vertical wall north of the grid point |
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287 | |
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288 | |
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289 | DO k = nzb+1, nzt-1 |
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290 | ! |
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291 | !-- Predetermine flag to mask topography and wall-bounded grid points. |
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292 | flag = MERGE( 1.0_wp, 0.0_wp, BTEST( wall_flags_total_0(k,j,i), 3 ) ) |
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293 | mask_east = MERGE( 1.0_wp, 0.0_wp, BTEST( wall_flags_total_0(k,j,i+1), 3 ) ) |
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294 | mask_west = MERGE( 1.0_wp, 0.0_wp, BTEST( wall_flags_total_0(k,j,i-1), 3 ) ) |
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295 | mask_south = MERGE( 1.0_wp, 0.0_wp, BTEST( wall_flags_total_0(k,j-1,i), 3 ) ) |
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296 | mask_north = MERGE( 1.0_wp, 0.0_wp, BTEST( wall_flags_total_0(k,j+1,i), 3 ) ) |
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297 | ! |
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298 | !-- Interpolate eddy diffusivities on staggered gridpoints |
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299 | kmxp = 0.25_wp * ( km(k,j,i)+km(k,j,i+1)+km(k+1,j,i)+km(k+1,j,i+1) ) |
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300 | kmxm = 0.25_wp * ( km(k,j,i)+km(k,j,i-1)+km(k+1,j,i)+km(k+1,j,i-1) ) |
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301 | kmyp = 0.25_wp * ( km(k,j,i)+km(k+1,j,i)+km(k,j+1,i)+km(k+1,j+1,i) ) |
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302 | kmym = 0.25_wp * ( km(k,j,i)+km(k+1,j,i)+km(k,j-1,i)+km(k+1,j-1,i) ) |
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303 | |
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304 | tend(k,j,i) = tend(k,j,i) & |
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305 | + ( mask_east * kmxp * ( & |
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306 | ( w(k,j,i+1) - w(k,j,i) ) * ddx & |
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307 | + ( u(k+1,j,i+1) - u(k,j,i+1) ) * ddzu(k+1) & |
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308 | ) & |
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309 | - mask_west * kmxm * ( & |
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310 | ( w(k,j,i) - w(k,j,i-1) ) * ddx & |
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311 | + ( u(k+1,j,i) - u(k,j,i) ) * ddzu(k+1) & |
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312 | ) & |
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313 | ) * ddx * flag & |
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314 | + ( mask_north * kmyp * ( & |
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315 | ( w(k,j+1,i) - w(k,j,i) ) * ddy & |
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316 | + ( v(k+1,j+1,i) - v(k,j+1,i) ) * ddzu(k+1) & |
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317 | ) & |
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318 | - mask_south * kmym * ( & |
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319 | ( w(k,j,i) - w(k,j-1,i) ) * ddy & |
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320 | + ( v(k+1,j,i) - v(k,j,i) ) * ddzu(k+1) & |
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321 | ) & |
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322 | ) * ddy * flag & |
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323 | + 2.0_wp * ( & |
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324 | km(k+1,j,i) * ( w(k+1,j,i) - w(k,j,i) ) * ddzw(k+1) & |
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325 | * rho_air(k+1) & |
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326 | - km(k,j,i) * ( w(k,j,i) - w(k-1,j,i) ) * ddzw(k) & |
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327 | * rho_air(k) & |
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328 | ) * ddzu(k+1) * drho_air_zw(k) * flag |
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329 | ENDDO |
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330 | ! |
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331 | !-- Add horizontal momentum flux v'w' at north- (l=0) and south-facing (l=1) |
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332 | !-- surfaces. Note, in the the flat case, loops won't be entered as |
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333 | !-- start_index > end_index. Furtermore, note, no vertical natural surfaces |
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334 | !-- so far. |
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335 | !-- Default-type surfaces |
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336 | DO l = 0, 1 |
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337 | surf_s = surf_def_v(l)%start_index(j,i) |
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338 | surf_e = surf_def_v(l)%end_index(j,i) |
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339 | DO m = surf_s, surf_e |
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340 | k = surf_def_v(l)%k(m) |
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341 | tend(k,j,i) = tend(k,j,i) + & |
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342 | surf_def_v(l)%mom_flux_w(m) * ddy |
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343 | ENDDO |
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344 | ENDDO |
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345 | ! |
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346 | !-- Natural-type surfaces |
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347 | DO l = 0, 1 |
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348 | surf_s = surf_lsm_v(l)%start_index(j,i) |
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349 | surf_e = surf_lsm_v(l)%end_index(j,i) |
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350 | DO m = surf_s, surf_e |
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351 | k = surf_lsm_v(l)%k(m) |
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352 | tend(k,j,i) = tend(k,j,i) + & |
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353 | surf_lsm_v(l)%mom_flux_w(m) * ddy |
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354 | ENDDO |
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355 | ENDDO |
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356 | ! |
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357 | !-- Urban-type surfaces |
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358 | DO l = 0, 1 |
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359 | surf_s = surf_usm_v(l)%start_index(j,i) |
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360 | surf_e = surf_usm_v(l)%end_index(j,i) |
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361 | DO m = surf_s, surf_e |
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362 | k = surf_usm_v(l)%k(m) |
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363 | tend(k,j,i) = tend(k,j,i) + & |
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364 | surf_usm_v(l)%mom_flux_w(m) * ddy |
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365 | ENDDO |
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366 | ENDDO |
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367 | ! |
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368 | !-- Add horizontal momentum flux u'w' at east- (l=2) and west-facing (l=3) |
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369 | !-- surfaces. |
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370 | !-- Default-type surfaces |
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371 | DO l = 2, 3 |
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372 | surf_s = surf_def_v(l)%start_index(j,i) |
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373 | surf_e = surf_def_v(l)%end_index(j,i) |
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374 | DO m = surf_s, surf_e |
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375 | k = surf_def_v(l)%k(m) |
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376 | tend(k,j,i) = tend(k,j,i) + & |
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377 | surf_def_v(l)%mom_flux_w(m) * ddx |
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378 | ENDDO |
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379 | ENDDO |
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380 | ! |
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381 | !-- Natural-type surfaces |
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382 | DO l = 2, 3 |
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383 | surf_s = surf_lsm_v(l)%start_index(j,i) |
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384 | surf_e = surf_lsm_v(l)%end_index(j,i) |
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385 | DO m = surf_s, surf_e |
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386 | k = surf_lsm_v(l)%k(m) |
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387 | tend(k,j,i) = tend(k,j,i) + & |
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388 | surf_lsm_v(l)%mom_flux_w(m) * ddx |
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389 | ENDDO |
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390 | ENDDO |
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391 | ! |
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392 | !-- Urban-type surfaces |
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393 | DO l = 2, 3 |
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394 | surf_s = surf_usm_v(l)%start_index(j,i) |
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395 | surf_e = surf_usm_v(l)%end_index(j,i) |
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396 | DO m = surf_s, surf_e |
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397 | k = surf_usm_v(l)%k(m) |
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398 | tend(k,j,i) = tend(k,j,i) + & |
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399 | surf_usm_v(l)%mom_flux_w(m) * ddx |
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400 | ENDDO |
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401 | ENDDO |
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402 | |
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403 | |
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404 | END SUBROUTINE diffusion_w_ij |
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405 | |
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406 | END MODULE diffusion_w_mod |
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