1 | ! $Id: disvert.F90 2153 2014-11-24 15:18:11Z acaubel $ |
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2 | |
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3 | SUBROUTINE disvert() |
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4 | |
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5 | #ifdef CPP_IOIPSL |
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6 | use ioipsl, only: getin |
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7 | #else |
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8 | USE ioipsl_getincom, only: getin |
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9 | #endif |
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10 | use new_unit_m, only: new_unit |
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11 | use assert_m, only: assert |
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12 | |
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13 | IMPLICIT NONE |
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14 | |
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15 | include "dimensions.h" |
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16 | include "paramet.h" |
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17 | include "comvert.h" |
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18 | include "comconst.h" |
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19 | include "iniprint.h" |
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20 | include "logic.h" |
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21 | |
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22 | !------------------------------------------------------------------------------- |
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23 | ! Purpose: Vertical distribution functions for LMDZ. |
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24 | ! Triggered by the levels number llm. |
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25 | !------------------------------------------------------------------------------- |
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26 | ! Read in "comvert.h": |
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27 | |
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28 | ! pa !--- vertical coordinate is close to a PRESSURE COORDINATE FOR P |
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29 | ! < 0.3 * pa (relative variation of p on a model level is < 0.1 %) |
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30 | |
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31 | ! preff !--- REFERENCE PRESSURE (101325 Pa) |
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32 | ! Written in "comvert.h": |
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33 | ! ap(llm+1), bp(llm+1) !--- Ap, Bp HYBRID COEFFICIENTS AT INTERFACES |
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34 | ! aps(llm), bps(llm) !--- Ap, Bp HYBRID COEFFICIENTS AT MID-LAYERS |
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35 | ! dpres(llm) !--- PRESSURE DIFFERENCE FOR EACH LAYER |
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36 | ! presnivs(llm) !--- PRESSURE AT EACH MID-LAYER |
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37 | ! scaleheight !--- VERTICAL SCALE HEIGHT (Earth: 8kms) |
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38 | ! nivsig(llm+1) !--- SIGMA INDEX OF EACH LAYER INTERFACE |
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39 | ! nivsigs(llm) !--- SIGMA INDEX OF EACH MID-LAYER |
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40 | !------------------------------------------------------------------------------- |
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41 | ! Local variables: |
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42 | REAL sig(llm+1), dsig(llm) |
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43 | REAL sig0(llm+1), zz(llm+1) |
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44 | REAL zk, zkm1, dzk1, dzk2, z, k0, k1 |
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45 | |
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46 | INTEGER l, unit |
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47 | REAL dsigmin |
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48 | REAL vert_scale,vert_dzmin,vert_dzlow,vert_z0low,vert_dzmid,vert_z0mid,vert_h_mid,vert_dzhig,vert_z0hig,vert_h_hig |
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49 | |
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50 | REAL alpha, beta, deltaz |
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51 | REAL x |
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52 | character(len=*),parameter :: modname="disvert" |
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53 | |
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54 | character(len=24):: vert_sampling |
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55 | ! (allowed values are "param", "tropo", "strato" and "read") |
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56 | |
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57 | !----------------------------------------------------------------------- |
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58 | |
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59 | WRITE(lunout,*) TRIM(modname)//" starts" |
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60 | |
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61 | ! default scaleheight is 8km for earth |
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62 | scaleheight=8. |
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63 | |
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64 | vert_sampling = merge("strato", "tropo ", ok_strato) ! default value |
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65 | call getin('vert_sampling', vert_sampling) |
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66 | WRITE(lunout,*) TRIM(modname)//' vert_sampling = ' // vert_sampling |
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67 | if (llm==39 .and. vert_sampling=="strato") then |
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68 | dsigmin=0.3 ! Vieille option par défaut pour CMIP5 |
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69 | else |
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70 | dsigmin=1. |
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71 | endif |
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72 | call getin('dsigmin', dsigmin) |
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73 | WRITE(LUNOUT,*) trim(modname), 'Discretisation verticale DSIGMIN=',dsigmin |
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74 | |
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75 | |
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76 | select case (vert_sampling) |
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77 | case ("param") |
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78 | ! On lit les options dans sigma.def: |
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79 | OPEN(99, file='sigma.def', status='old', form='formatted') |
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80 | READ(99, *) scaleheight ! hauteur d'echelle 8. |
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81 | READ(99, *) deltaz ! epaiseur de la premiere couche 0.04 |
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82 | READ(99, *) beta ! facteur d'acroissement en haut 1.3 |
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83 | READ(99, *) k0 ! nombre de couches dans la transition surf |
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84 | READ(99, *) k1 ! nombre de couches dans la transition haute |
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85 | CLOSE(99) |
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86 | alpha=deltaz/(llm*scaleheight) |
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87 | write(lunout, *)trim(modname),':scaleheight, alpha, k0, k1, beta', & |
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88 | scaleheight, alpha, k0, k1, beta |
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89 | |
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90 | alpha=deltaz/tanh(1./k0)*2. |
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91 | zkm1=0. |
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92 | sig(1)=1. |
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93 | do l=1, llm |
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94 | sig(l+1)=(cosh(l/k0))**(-alpha*k0/scaleheight) & |
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95 | *exp(-alpha/scaleheight*tanh((llm-k1)/k0) & |
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96 | *beta**(l-(llm-k1))/log(beta)) |
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97 | zk=-scaleheight*log(sig(l+1)) |
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98 | |
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99 | dzk1=alpha*tanh(l/k0) |
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100 | dzk2=alpha*tanh((llm-k1)/k0)*beta**(l-(llm-k1))/log(beta) |
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101 | write(lunout, *)l, sig(l+1), zk, zk-zkm1, dzk1, dzk2 |
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102 | zkm1=zk |
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103 | enddo |
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104 | |
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105 | sig(llm+1)=0. |
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106 | |
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107 | bp(: llm) = EXP(1. - 1. / sig(: llm)**2) |
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108 | bp(llmp1) = 0. |
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109 | |
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110 | ap = pa * (sig - bp) |
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111 | case("sigma") |
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112 | DO l = 1, llm |
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113 | x = 2*asin(1.) * (l - 0.5) / (llm + 1) |
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114 | dsig(l) = dsigmin + 7.0 * SIN(x)**2 |
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115 | ENDDO |
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116 | dsig = dsig / sum(dsig) |
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117 | sig(llm+1) = 0. |
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118 | DO l = llm, 1, -1 |
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119 | sig(l) = sig(l+1) + dsig(l) |
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120 | ENDDO |
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121 | |
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122 | bp(1)=1. |
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123 | bp(2: llm) = sig(2:llm) |
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124 | bp(llmp1) = 0. |
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125 | ap(:)=0. |
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126 | case("tropo") |
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127 | DO l = 1, llm |
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128 | x = 2*asin(1.) * (l - 0.5) / (llm + 1) |
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129 | dsig(l) = dsigmin + 7.0 * SIN(x)**2 |
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130 | ENDDO |
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131 | dsig = dsig / sum(dsig) |
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132 | sig(llm+1) = 0. |
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133 | DO l = llm, 1, -1 |
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134 | sig(l) = sig(l+1) + dsig(l) |
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135 | ENDDO |
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136 | |
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137 | bp(1)=1. |
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138 | bp(2: llm) = EXP(1. - 1. / sig(2: llm)**2) |
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139 | bp(llmp1) = 0. |
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140 | |
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141 | ap(1)=0. |
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142 | ap(2: llm + 1) = pa * (sig(2: llm + 1) - bp(2: llm + 1)) |
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143 | case("strato") |
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144 | DO l = 1, llm |
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145 | x = 2*asin(1.) * (l - 0.5) / (llm + 1) |
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146 | dsig(l) =(dsigmin + 7. * SIN(x)**2) & |
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147 | *(0.5*(1.-tanh(1.*(x-asin(1.))/asin(1.))))**2 |
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148 | ENDDO |
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149 | dsig = dsig / sum(dsig) |
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150 | sig(llm+1) = 0. |
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151 | DO l = llm, 1, -1 |
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152 | sig(l) = sig(l+1) + dsig(l) |
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153 | ENDDO |
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154 | |
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155 | bp(1)=1. |
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156 | bp(2: llm) = EXP(1. - 1. / sig(2: llm)**2) |
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157 | bp(llmp1) = 0. |
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158 | |
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159 | ap(1)=0. |
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160 | ap(2: llm + 1) = pa * (sig(2: llm + 1) - bp(2: llm + 1)) |
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161 | case("strato_correct") |
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162 | !================================================================== |
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163 | ! Fredho 2014/05/18, Saint-Louis du Senegal |
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164 | ! Cette version de la discretisation strato est corrige au niveau |
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165 | ! du passage des sig aux ap, bp |
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166 | ! la version precedente donne un coude dans l'epaisseur des couches |
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167 | ! vers la tropopause |
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168 | !================================================================== |
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169 | |
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170 | |
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171 | DO l = 1, llm |
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172 | x = 2*asin(1.) * (l - 0.5) / (llm + 1) |
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173 | dsig(l) =(dsigmin + 7. * SIN(x)**2) & |
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174 | *(0.5*(1.-tanh(1.*(x-asin(1.))/asin(1.))))**2 |
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175 | ENDDO |
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176 | dsig = dsig / sum(dsig) |
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177 | sig0(llm+1) = 0. |
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178 | DO l = llm, 1, -1 |
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179 | sig0(l) = sig0(l+1) + dsig(l) |
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180 | ENDDO |
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181 | sig=racinesig(sig0) |
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182 | |
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183 | bp(1)=1. |
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184 | bp(2:llm)=EXP(1.-1./sig(2: llm)**2) |
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185 | bp(llmp1)=0. |
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186 | |
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187 | ap(1)=0. |
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188 | ap(2:llm)=pa*(sig(2:llm)-bp(2:llm)) |
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189 | ap(llm+1)=0. |
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190 | |
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191 | CASE("strato_custom0") |
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192 | !======================================================= |
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193 | ! Version Transitoire |
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194 | ! custumize strato distribution with specific alpha & beta values and function |
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195 | ! depending on llm (experimental and temporary)! |
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196 | SELECT CASE (llm) |
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197 | CASE(55) |
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198 | alpha=0.45 |
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199 | beta=4.0 |
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200 | CASE(63) |
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201 | alpha=0.45 |
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202 | beta=5.0 |
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203 | CASE(71) |
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204 | alpha=3.05 |
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205 | beta=65. |
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206 | CASE(79) |
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207 | alpha=3.20 |
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208 | ! alpha=2.05 ! FLOTT 79 (PLANTE) |
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209 | beta=70. |
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210 | END SELECT |
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211 | ! Or used values provided by user in def file: |
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212 | CALL getin("strato_alpha",alpha) |
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213 | CALL getin("strato_beta",beta) |
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214 | |
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215 | ! Build geometrical distribution |
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216 | scaleheight=7. |
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217 | zz(1)=0. |
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218 | IF (llm==55.OR.llm==63) THEN |
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219 | DO l=1,llm |
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220 | z=zz(l)/scaleheight |
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221 | zz(l+1)=zz(l)+0.03+z*1.5*(1.-TANH(z-0.5))+alpha*(1.+TANH(z-1.5)) & |
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222 | +5.0*EXP((l-llm)/beta) |
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223 | ENDDO |
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224 | ELSEIF (llm==71) THEN !.OR.llm==79) THEN ! FLOTT 79 (PLANTE) |
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225 | DO l=1,llm |
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226 | z=zz(l) |
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227 | zz(l+1)=zz(l)+0.02+0.88*TANH(z/2.5)+alpha*(1.+TANH((z-beta)/15.)) |
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228 | ENDDO |
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229 | ELSEIF (llm==79) THEN |
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230 | DO l=1,llm |
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231 | z=zz(l) |
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232 | zz(l+1)=zz(l)+0.02+0.80*TANH(z/3.8)+alpha*(1+TANH((z-beta)/17.)) & |
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233 | +0.03*TANH(z/.25) |
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234 | ENDDO |
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235 | ENDIF ! of IF (llm==55.OR.llm==63) ... |
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236 | |
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237 | |
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238 | ! Build sigma distribution |
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239 | sig0=EXP(-zz(:)/scaleheight) |
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240 | sig0(llm+1)=0. |
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241 | ! sig=ridders(sig0) |
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242 | sig=racinesig(sig0) |
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243 | |
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244 | ! Compute ap() and bp() |
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245 | bp(1)=1. |
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246 | bp(2:llm)=EXP(1.-1./sig(2:llm)**2) |
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247 | bp(llm+1)=0. |
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248 | ap=pa*(sig-bp) |
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249 | |
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250 | CASE("strato_custom") |
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251 | !=================================================================== |
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252 | ! David Cugnet, François Lott, Lionel Guez, Ehouoarn Millour, Fredho |
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253 | ! 2014/05 |
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254 | ! custumize strato distribution |
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255 | ! Al the parameter are given in km assuming a given scalehigh |
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256 | vert_scale=7. ! scale hight |
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257 | vert_dzmin=0.02 ! width of first layer |
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258 | vert_dzlow=1. ! dz in the low atmosphere |
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259 | vert_z0low=8. ! height at which resolution recches dzlow |
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260 | vert_dzmid=3. ! dz in the mid atmsophere |
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261 | vert_z0mid=70. ! height at which resolution recches dzmid |
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262 | vert_h_mid=20. ! width of the transition |
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263 | vert_dzhig=11. ! dz in the high atmsophere |
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264 | vert_z0hig=80. ! height at which resolution recches dz |
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265 | vert_h_hig=20. ! width of the transition |
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266 | !=================================================================== |
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267 | |
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268 | call getin('vert_scale',vert_scale) |
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269 | call getin('vert_dzmin',vert_dzmin) |
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270 | call getin('vert_dzlow',vert_dzlow) |
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271 | call getin('vert_z0low',vert_z0low) |
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272 | CALL getin('vert_dzmid',vert_dzmid) |
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273 | CALL getin('vert_z0mid',vert_z0mid) |
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274 | call getin('vert_h_mid',vert_h_mid) |
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275 | call getin('vert_dzhig',vert_dzhig) |
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276 | call getin('vert_z0hig',vert_z0hig) |
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277 | call getin('vert_h_hig',vert_h_hig) |
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278 | |
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279 | scaleheight=vert_scale ! for consistency with further computations |
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280 | ! Build geometrical distribution |
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281 | zz(1)=0. |
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282 | DO l=1,llm |
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283 | z=zz(l) |
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284 | zz(l+1)=zz(l)+vert_dzmin+vert_dzlow*TANH(z/vert_z0low)+ & |
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285 | & (vert_dzmid-vert_dzlow)* & |
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286 | & (TANH((z-vert_z0mid)/vert_h_mid)-TANH((-vert_z0mid)/vert_h_mid)) & |
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287 | & +(vert_dzhig-vert_dzmid-vert_dzlow)* & |
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288 | & (TANH((z-vert_z0hig)/vert_h_hig)-TANH((-vert_z0hig)/vert_h_hig)) |
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289 | ENDDO |
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290 | |
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291 | |
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292 | !=================================================================== |
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293 | ! Comment added Fredho 2014/05/18, Saint-Louis, Senegal |
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294 | ! From approximate z to ap, bp, so that p=ap+bp*p0 and p/p0=exp(-z/H) |
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295 | ! sig0 is p/p0 |
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296 | ! sig is an intermediate distribution introduce to estimate bp |
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297 | ! 1. sig0=exp(-z/H) |
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298 | ! 2. inversion of sig0=(1-pa/p0)*sig+(1-pa/p0)*exp(1-1/sig**2) |
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299 | ! 3. bp=exp(1-1/sig**2) |
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300 | ! 4. ap deduced from the combination of 2 and 3 so that sig0=ap/p0+bp |
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301 | !=================================================================== |
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302 | |
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303 | sig0=EXP(-zz(:)/vert_scale) |
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304 | sig0(llm+1)=0. |
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305 | sig=racinesig(sig0) |
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306 | bp(1)=1. |
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307 | bp(2:llm)=EXP(1.-1./sig(2:llm)**2) |
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308 | bp(llm+1)=0. |
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309 | ap=pa*(sig-bp) |
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310 | |
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311 | case("read") |
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312 | ! Read "ap" and "bp". First line is skipped (title line). "ap" |
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313 | ! should be in Pa. First couple of values should correspond to |
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314 | ! the surface, that is : "bp" should be in descending order. |
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315 | call new_unit(unit) |
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316 | open(unit, file="hybrid.txt", status="old", action="read", & |
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317 | position="rewind") |
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318 | read(unit, fmt=*) ! skip title line |
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319 | do l = 1, llm + 1 |
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320 | read(unit, fmt=*) ap(l), bp(l) |
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321 | end do |
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322 | close(unit) |
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323 | call assert(ap(1) == 0., ap(llm + 1) == 0., bp(1) == 1., & |
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324 | bp(llm + 1) == 0., "disvert: bad ap or bp values") |
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325 | case default |
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326 | call abort_gcm("disvert", 'Wrong value for "vert_sampling"', 1) |
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327 | END select |
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328 | |
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329 | DO l=1, llm |
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330 | nivsigs(l) = REAL(l) |
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331 | ENDDO |
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332 | |
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333 | DO l=1, llmp1 |
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334 | nivsig(l)= REAL(l) |
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335 | ENDDO |
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336 | |
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337 | write(lunout, *) trim(modname),': BP ' |
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338 | write(lunout, *) bp |
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339 | write(lunout, *) trim(modname),': AP ' |
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340 | write(lunout, *) ap |
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341 | |
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342 | write(lunout, *) 'Niveaux de pressions approximatifs aux centres des' |
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343 | write(lunout, *)'couches calcules pour une pression de surface =', preff |
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344 | write(lunout, *) 'et altitudes equivalentes pour une hauteur d echelle de ' |
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345 | write(lunout, *) scaleheight,' km' |
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346 | DO l = 1, llm |
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347 | dpres(l) = bp(l) - bp(l+1) |
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348 | presnivs(l) = 0.5 *( ap(l)+bp(l)*preff + ap(l+1)+bp(l+1)*preff ) |
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349 | write(lunout, *)'PRESNIVS(', l, ')=', presnivs(l), ' Z ~ ', & |
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350 | log(preff/presnivs(l))*scaleheight & |
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351 | , ' DZ ~ ', scaleheight*log((ap(l)+bp(l)*preff)/ & |
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352 | max(ap(l+1)+bp(l+1)*preff, 1.e-10)) |
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353 | ENDDO |
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354 | |
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355 | write(lunout, *) trim(modname),': PRESNIVS ' |
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356 | write(lunout, *) presnivs |
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357 | |
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358 | CONTAINS |
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359 | |
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360 | !------------------------------------------------------------------------------- |
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361 | ! |
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362 | FUNCTION ridders(sig) RESULT(sg) |
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363 | ! |
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364 | !------------------------------------------------------------------------------- |
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365 | IMPLICIT NONE |
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366 | !------------------------------------------------------------------------------- |
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367 | ! Purpose: Search for s solving (Pa/Preff)*s+(1-Pa/Preff)*EXP(1-1./s**2)=sg |
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368 | ! Notes: Uses Ridders' method, quite robust. Initial bracketing: 0<=sg<=1. |
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369 | ! Reference: Ridders, C. F. J. "A New Algorithm for Computing a Single Root of a |
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370 | ! Real Continuous Function" IEEE Trans. Circuits Systems 26, 979-980, 1979 |
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371 | !------------------------------------------------------------------------------- |
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372 | ! Arguments: |
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373 | REAL, INTENT(IN) :: sig(:) |
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374 | REAL :: sg(SIZE(sig)) |
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375 | !------------------------------------------------------------------------------- |
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376 | ! Local variables: |
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377 | INTEGER :: it, ns, maxit |
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378 | REAL :: c1, c2, x1, x2, x3, x4, f1, f2, f3, f4, s, xx, distrib |
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379 | !------------------------------------------------------------------------------- |
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380 | ns=SIZE(sig); maxit=9999 |
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381 | c1=Pa/Preff; c2=1.-c1 |
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382 | DO l=1,ns |
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383 | xx=HUGE(1.) |
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384 | x1=0.0; f1=distrib(x1,c1,c2,sig(l)) |
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385 | x2=1.0; f2=distrib(x2,c1,c2,sig(l)) |
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386 | DO it=1,maxit |
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387 | x3=0.5*(x1+x2); f3=distrib(x3,c1,c2,sig(l)) |
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388 | s=SQRT(f3**2-f1*f2); IF(s==0.) EXIT |
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389 | x4=x3+(x3-x1)*(SIGN(1.,f1-f2)*f3/s); IF(ABS(10.*LOG(x4-xx))<=1E-5) EXIT |
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390 | xx=x4; f4=distrib(x4,c1,c2,sig(l)); IF(f4==0.) EXIT |
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391 | IF(SIGN(f3,f4)/=f3) THEN; x1=x3; f1=f3; x2=xx; f2=f4 |
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392 | ELSE IF(SIGN(f1,f4)/=f1) THEN; x2=xx; f2=f4 |
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393 | ELSE IF(SIGN(f2,f4)/=f2) THEN; x1=xx; f1=f4 |
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394 | ELSE; CALL abort_gcm("ridders",'Algorithm failed (which is odd...') |
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395 | END IF |
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396 | IF(ABS(10.*LOG(ABS(x2-x1)))<=1E-5) EXIT !--- ERROR ON SIG <= 0.01m |
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397 | END DO |
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398 | IF(it==maxit+1) WRITE(lunout,'(a,i3)')'WARNING in ridder: failed to converg& |
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399 | &e for level ',l |
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400 | sg(l)=xx |
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401 | END DO |
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402 | sg(1)=1.; sg(ns)=0. |
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403 | |
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404 | END FUNCTION ridders |
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405 | |
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406 | FUNCTION racinesig(sig) RESULT(sg) |
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407 | ! |
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408 | !------------------------------------------------------------------------------- |
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409 | IMPLICIT NONE |
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410 | !------------------------------------------------------------------------------- |
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411 | ! Fredho 2014/05/18 |
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412 | ! Purpose: Search for s solving (Pa/Preff)*sg+(1-Pa/Preff)*EXP(1-1./sg**2)=s |
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413 | ! Notes: Uses Newton Raphson search |
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414 | !------------------------------------------------------------------------------- |
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415 | ! Arguments: |
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416 | REAL, INTENT(IN) :: sig(:) |
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417 | REAL :: sg(SIZE(sig)) |
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418 | !------------------------------------------------------------------------------- |
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419 | ! Local variables: |
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420 | INTEGER :: it, ns, maxit |
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421 | REAL :: c1, c2, x1, x2, x3, x4, f1, f2, f3, f4, s, xx, distrib |
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422 | !------------------------------------------------------------------------------- |
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423 | ns=SIZE(sig); maxit=100 |
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424 | c1=Pa/Preff; c2=1.-c1 |
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425 | DO l=2,ns-1 |
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426 | sg(l)=sig(l) |
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427 | DO it=1,maxit |
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428 | f1=exp(1-1./sg(l)**2)*(1.-c1) |
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429 | sg(l)=sg(l)-(c1*sg(l)+f1-sig(l))/(c1+2*f1*sg(l)**(-3)) |
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430 | ENDDO |
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431 | ! print*,'SSSSIG ',sig(l),sg(l),c1*sg(l)+exp(1-1./sg(l)**2)*(1.-c1) |
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432 | ENDDO |
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433 | sg(1)=1.; sg(ns)=0. |
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434 | |
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435 | END FUNCTION racinesig |
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436 | |
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437 | |
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438 | |
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439 | |
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440 | END SUBROUTINE disvert |
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441 | |
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442 | !------------------------------------------------------------------------------- |
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443 | |
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444 | FUNCTION distrib(x,c1,c2,x0) RESULT(res) |
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445 | ! |
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446 | !------------------------------------------------------------------------------- |
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447 | ! Arguments: |
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448 | REAL, INTENT(IN) :: x, c1, c2, x0 |
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449 | REAL :: res |
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450 | !------------------------------------------------------------------------------- |
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451 | res=c1*x+c2*EXP(1-1/(x**2))-x0 |
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452 | |
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453 | END FUNCTION distrib |
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454 | |
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455 | |
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