1 | !------------------------------------------------------------------------------- |
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2 | module module_gfs_funcphys |
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3 | !$$$ Module Documentation Block |
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4 | ! |
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5 | ! Module: funcphys API for basic thermodynamic physics |
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6 | ! Author: Iredell Org: W/NX23 Date: 1999-03-01 |
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7 | ! |
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8 | ! Abstract: This module provides an Application Program Interface |
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9 | ! for computing basic thermodynamic physics functions, in particular |
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10 | ! (1) saturation vapor pressure as a function of temperature, |
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11 | ! (2) dewpoint temperature as a function of vapor pressure, |
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12 | ! (3) equivalent potential temperature as a function of temperature |
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13 | ! and scaled pressure to the kappa power, |
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14 | ! (4) temperature and specific humidity along a moist adiabat |
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15 | ! as functions of equivalent potential temperature and |
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16 | ! scaled pressure to the kappa power, |
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17 | ! (5) scaled pressure to the kappa power as a function of pressure, and |
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18 | ! (6) temperature at the lifting condensation level as a function |
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19 | ! of temperature and dewpoint depression. |
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20 | ! The entry points required to set up lookup tables start with a "g". |
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21 | ! All the other entry points are functions starting with an "f" or |
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22 | ! are subroutines starting with an "s". These other functions and |
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23 | ! subroutines are elemental; that is, they return a scalar if they |
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24 | ! are passed only scalars, but they return an array if they are passed |
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25 | ! an array. These other functions and subroutines can be inlined, too. |
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26 | ! |
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27 | ! Program History Log: |
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28 | ! 1999-03-01 Mark Iredell |
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29 | ! 1999-10-15 Mark Iredell SI unit for pressure (Pascals) |
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30 | ! 2001-02-26 Mark Iredell Ice phase changes of Hong and Moorthi |
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31 | ! |
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32 | ! Public Variables: |
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33 | ! krealfp Integer parameter kind or length of reals (=kind_phys) |
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34 | ! |
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35 | ! Public Subprograms: |
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36 | ! gpvsl Compute saturation vapor pressure over liquid table |
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37 | ! |
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38 | ! fpvsl Elementally compute saturation vapor pressure over liquid |
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39 | ! function result Real(krealfp) saturation vapor pressure in Pascals |
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40 | ! t Real(krealfp) temperature in Kelvin |
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41 | ! |
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42 | ! fpvslq Elementally compute saturation vapor pressure over liquid |
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43 | ! function result Real(krealfp) saturation vapor pressure in Pascals |
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44 | ! t Real(krealfp) temperature in Kelvin |
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45 | ! |
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46 | ! fpvslx Elementally compute saturation vapor pressure over liquid |
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47 | ! function result Real(krealfp) saturation vapor pressure in Pascals |
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48 | ! t Real(krealfp) temperature in Kelvin |
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49 | ! |
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50 | ! gpvsi Compute saturation vapor pressure over ice table |
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51 | ! |
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52 | ! fpvsi Elementally compute saturation vapor pressure over ice |
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53 | ! function result Real(krealfp) saturation vapor pressure in Pascals |
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54 | ! t Real(krealfp) temperature in Kelvin |
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55 | ! |
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56 | ! fpvsiq Elementally compute saturation vapor pressure over ice |
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57 | ! function result Real(krealfp) saturation vapor pressure in Pascals |
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58 | ! t Real(krealfp) temperature in Kelvin |
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59 | ! |
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60 | ! fpvsix Elementally compute saturation vapor pressure over ice |
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61 | ! function result Real(krealfp) saturation vapor pressure in Pascals |
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62 | ! t Real(krealfp) temperature in Kelvin |
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63 | ! |
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64 | ! gpvs Compute saturation vapor pressure table |
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65 | ! |
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66 | ! fpvs Elementally compute saturation vapor pressure |
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67 | ! function result Real(krealfp) saturation vapor pressure in Pascals |
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68 | ! t Real(krealfp) temperature in Kelvin |
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69 | ! |
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70 | ! fpvsq Elementally compute saturation vapor pressure |
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71 | ! function result Real(krealfp) saturation vapor pressure in Pascals |
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72 | ! t Real(krealfp) temperature in Kelvin |
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73 | ! |
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74 | ! fpvsx Elementally compute saturation vapor pressure |
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75 | ! function result Real(krealfp) saturation vapor pressure in Pascals |
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76 | ! t Real(krealfp) temperature in Kelvin |
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77 | ! |
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78 | ! gtdpl Compute dewpoint temperature over liquid table |
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79 | ! |
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80 | ! ftdpl Elementally compute dewpoint temperature over liquid |
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81 | ! function result Real(krealfp) dewpoint temperature in Kelvin |
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82 | ! pv Real(krealfp) vapor pressure in Pascals |
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83 | ! |
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84 | ! ftdplq Elementally compute dewpoint temperature over liquid |
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85 | ! function result Real(krealfp) dewpoint temperature in Kelvin |
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86 | ! pv Real(krealfp) vapor pressure in Pascals |
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87 | ! |
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88 | ! ftdplx Elementally compute dewpoint temperature over liquid |
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89 | ! function result Real(krealfp) dewpoint temperature in Kelvin |
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90 | ! pv Real(krealfp) vapor pressure in Pascals |
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91 | ! |
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92 | ! ftdplxg Elementally compute dewpoint temperature over liquid |
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93 | ! function result Real(krealfp) dewpoint temperature in Kelvin |
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94 | ! t Real(krealfp) guess dewpoint temperature in Kelvin |
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95 | ! pv Real(krealfp) vapor pressure in Pascals |
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96 | ! |
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97 | ! gtdpi Compute dewpoint temperature table over ice |
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98 | ! |
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99 | ! ftdpi Elementally compute dewpoint temperature over ice |
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100 | ! function result Real(krealfp) dewpoint temperature in Kelvin |
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101 | ! pv Real(krealfp) vapor pressure in Pascals |
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102 | ! |
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103 | ! ftdpiq Elementally compute dewpoint temperature over ice |
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104 | ! function result Real(krealfp) dewpoint temperature in Kelvin |
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105 | ! pv Real(krealfp) vapor pressure in Pascals |
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106 | ! |
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107 | ! ftdpix Elementally compute dewpoint temperature over ice |
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108 | ! function result Real(krealfp) dewpoint temperature in Kelvin |
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109 | ! pv Real(krealfp) vapor pressure in Pascals |
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110 | ! |
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111 | ! ftdpixg Elementally compute dewpoint temperature over ice |
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112 | ! function result Real(krealfp) dewpoint temperature in Kelvin |
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113 | ! t Real(krealfp) guess dewpoint temperature in Kelvin |
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114 | ! pv Real(krealfp) vapor pressure in Pascals |
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115 | ! |
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116 | ! gtdp Compute dewpoint temperature table |
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117 | ! |
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118 | ! ftdp Elementally compute dewpoint temperature |
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119 | ! function result Real(krealfp) dewpoint temperature in Kelvin |
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120 | ! pv Real(krealfp) vapor pressure in Pascals |
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121 | ! |
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122 | ! ftdpq Elementally compute dewpoint temperature |
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123 | ! function result Real(krealfp) dewpoint temperature in Kelvin |
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124 | ! pv Real(krealfp) vapor pressure in Pascals |
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125 | ! |
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126 | ! ftdpx Elementally compute dewpoint temperature |
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127 | ! function result Real(krealfp) dewpoint temperature in Kelvin |
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128 | ! pv Real(krealfp) vapor pressure in Pascals |
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129 | ! |
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130 | ! ftdpxg Elementally compute dewpoint temperature |
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131 | ! function result Real(krealfp) dewpoint temperature in Kelvin |
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132 | ! t Real(krealfp) guess dewpoint temperature in Kelvin |
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133 | ! pv Real(krealfp) vapor pressure in Pascals |
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134 | ! |
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135 | ! gthe Compute equivalent potential temperature table |
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136 | ! |
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137 | ! fthe Elementally compute equivalent potential temperature |
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138 | ! function result Real(krealfp) equivalent potential temperature in Kelvin |
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139 | ! t Real(krealfp) LCL temperature in Kelvin |
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140 | ! pk Real(krealfp) LCL pressure over 1e5 Pa to the kappa power |
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141 | ! |
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142 | ! ftheq Elementally compute equivalent potential temperature |
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143 | ! function result Real(krealfp) equivalent potential temperature in Kelvin |
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144 | ! t Real(krealfp) LCL temperature in Kelvin |
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145 | ! pk Real(krealfp) LCL pressure over 1e5 Pa to the kappa power |
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146 | ! |
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147 | ! fthex Elementally compute equivalent potential temperature |
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148 | ! function result Real(krealfp) equivalent potential temperature in Kelvin |
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149 | ! t Real(krealfp) LCL temperature in Kelvin |
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150 | ! pk Real(krealfp) LCL pressure over 1e5 Pa to the kappa power |
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151 | ! |
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152 | ! gtma Compute moist adiabat tables |
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153 | ! |
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154 | ! stma Elementally compute moist adiabat temperature and moisture |
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155 | ! the Real(krealfp) equivalent potential temperature in Kelvin |
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156 | ! pk Real(krealfp) pressure over 1e5 Pa to the kappa power |
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157 | ! tma Real(krealfp) parcel temperature in Kelvin |
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158 | ! qma Real(krealfp) parcel specific humidity in kg/kg |
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159 | ! |
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160 | ! stmaq Elementally compute moist adiabat temperature and moisture |
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161 | ! the Real(krealfp) equivalent potential temperature in Kelvin |
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162 | ! pk Real(krealfp) pressure over 1e5 Pa to the kappa power |
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163 | ! tma Real(krealfp) parcel temperature in Kelvin |
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164 | ! qma Real(krealfp) parcel specific humidity in kg/kg |
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165 | ! |
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166 | ! stmax Elementally compute moist adiabat temperature and moisture |
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167 | ! the Real(krealfp) equivalent potential temperature in Kelvin |
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168 | ! pk Real(krealfp) pressure over 1e5 Pa to the kappa power |
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169 | ! tma Real(krealfp) parcel temperature in Kelvin |
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170 | ! qma Real(krealfp) parcel specific humidity in kg/kg |
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171 | ! |
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172 | ! stmaxg Elementally compute moist adiabat temperature and moisture |
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173 | ! tg Real(krealfp) guess parcel temperature in Kelvin |
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174 | ! the Real(krealfp) equivalent potential temperature in Kelvin |
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175 | ! pk Real(krealfp) pressure over 1e5 Pa to the kappa power |
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176 | ! tma Real(krealfp) parcel temperature in Kelvin |
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177 | ! qma Real(krealfp) parcel specific humidity in kg/kg |
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178 | ! |
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179 | ! gpkap Compute pressure to the kappa table |
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180 | ! |
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181 | ! fpkap Elementally raise pressure to the kappa power. |
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182 | ! function result Real(krealfp) p over 1e5 Pa to the kappa power |
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183 | ! p Real(krealfp) pressure in Pascals |
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184 | ! |
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185 | ! fpkapq Elementally raise pressure to the kappa power. |
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186 | ! function result Real(krealfp) p over 1e5 Pa to the kappa power |
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187 | ! p Real(krealfp) pressure in Pascals |
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188 | ! |
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189 | ! fpkapo Elementally raise pressure to the kappa power. |
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190 | ! function result Real(krealfp) p over 1e5 Pa to the kappa power |
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191 | ! p Real(krealfp) surface pressure in Pascals |
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192 | ! |
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193 | ! fpkapx Elementally raise pressure to the kappa power. |
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194 | ! function result Real(krealfp) p over 1e5 Pa to the kappa power |
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195 | ! p Real(krealfp) pressure in Pascals |
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196 | ! |
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197 | ! grkap Compute pressure to the 1/kappa table |
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198 | ! |
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199 | ! frkap Elementally raise pressure to the 1/kappa power. |
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200 | ! function result Real(krealfp) pressure in Pascals |
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201 | ! pkap Real(krealfp) p over 1e5 Pa to the 1/kappa power |
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202 | ! |
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203 | ! frkapq Elementally raise pressure to the kappa power. |
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204 | ! function result Real(krealfp) pressure in Pascals |
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205 | ! pkap Real(krealfp) p over 1e5 Pa to the kappa power |
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206 | ! |
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207 | ! frkapx Elementally raise pressure to the kappa power. |
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208 | ! function result Real(krealfp) pressure in Pascals |
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209 | ! pkap Real(krealfp) p over 1e5 Pa to the kappa power |
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210 | ! |
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211 | ! gtlcl Compute LCL temperature table |
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212 | ! |
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213 | ! ftlcl Elementally compute LCL temperature. |
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214 | ! function result Real(krealfp) temperature at the LCL in Kelvin |
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215 | ! t Real(krealfp) temperature in Kelvin |
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216 | ! tdpd Real(krealfp) dewpoint depression in Kelvin |
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217 | ! |
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218 | ! ftlclq Elementally compute LCL temperature. |
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219 | ! function result Real(krealfp) temperature at the LCL in Kelvin |
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220 | ! t Real(krealfp) temperature in Kelvin |
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221 | ! tdpd Real(krealfp) dewpoint depression in Kelvin |
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222 | ! |
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223 | ! ftlclo Elementally compute LCL temperature. |
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224 | ! function result Real(krealfp) temperature at the LCL in Kelvin |
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225 | ! t Real(krealfp) temperature in Kelvin |
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226 | ! tdpd Real(krealfp) dewpoint depression in Kelvin |
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227 | ! |
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228 | ! ftlclx Elementally compute LCL temperature. |
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229 | ! function result Real(krealfp) temperature at the LCL in Kelvin |
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230 | ! t Real(krealfp) temperature in Kelvin |
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231 | ! tdpd Real(krealfp) dewpoint depression in Kelvin |
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232 | ! |
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233 | ! gfuncphys Compute all physics function tables |
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234 | ! |
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235 | ! Attributes: |
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236 | ! Language: Fortran 90 |
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237 | ! |
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238 | !$$$ |
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239 | use module_gfs_machine,only:kind_phys |
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240 | use module_gfs_physcons |
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241 | implicit none |
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242 | private |
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243 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
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244 | ! Public Variables |
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245 | ! integer,public,parameter:: krealfp=selected_real_kind(15,45) |
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246 | integer,public,parameter:: krealfp=kind_phys |
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247 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
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248 | ! Private Variables |
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249 | real(krealfp),parameter:: psatb=con_psat*1.e-5 |
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250 | integer,parameter:: nxpvsl=7501 |
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251 | real(krealfp) c1xpvsl,c2xpvsl,tbpvsl(nxpvsl) |
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252 | integer,parameter:: nxpvsi=7501 |
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253 | real(krealfp) c1xpvsi,c2xpvsi,tbpvsi(nxpvsi) |
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254 | integer,parameter:: nxpvs=7501 |
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255 | real(krealfp) c1xpvs,c2xpvs,tbpvs(nxpvs) |
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256 | integer,parameter:: nxtdpl=5001 |
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257 | real(krealfp) c1xtdpl,c2xtdpl,tbtdpl(nxtdpl) |
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258 | integer,parameter:: nxtdpi=5001 |
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259 | real(krealfp) c1xtdpi,c2xtdpi,tbtdpi(nxtdpi) |
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260 | integer,parameter:: nxtdp=5001 |
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261 | real(krealfp) c1xtdp,c2xtdp,tbtdp(nxtdp) |
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262 | integer,parameter:: nxthe=241,nythe=151 |
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263 | real(krealfp) c1xthe,c2xthe,c1ythe,c2ythe,tbthe(nxthe,nythe) |
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264 | integer,parameter:: nxma=151,nyma=121 |
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265 | real(krealfp) c1xma,c2xma,c1yma,c2yma,tbtma(nxma,nyma),tbqma(nxma,nyma) |
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266 | ! integer,parameter:: nxpkap=5501 |
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267 | integer,parameter:: nxpkap=11001 |
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268 | real(krealfp) c1xpkap,c2xpkap,tbpkap(nxpkap) |
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269 | integer,parameter:: nxrkap=5501 |
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270 | real(krealfp) c1xrkap,c2xrkap,tbrkap(nxrkap) |
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271 | integer,parameter:: nxtlcl=151,nytlcl=61 |
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272 | real(krealfp) c1xtlcl,c2xtlcl,c1ytlcl,c2ytlcl,tbtlcl(nxtlcl,nytlcl) |
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273 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
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274 | ! Public Subprograms |
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275 | public gpvsl,fpvsl,fpvslq,fpvslx |
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276 | public gpvsi,fpvsi,fpvsiq,fpvsix |
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277 | public gpvs,fpvs,fpvsq,fpvsx |
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278 | public gtdpl,ftdpl,ftdplq,ftdplx,ftdplxg |
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279 | public gtdpi,ftdpi,ftdpiq,ftdpix,ftdpixg |
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280 | public gtdp,ftdp,ftdpq,ftdpx,ftdpxg |
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281 | public gthe,fthe,ftheq,fthex |
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282 | public gtma,stma,stmaq,stmax,stmaxg |
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283 | public gpkap,fpkap,fpkapq,fpkapo,fpkapx |
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284 | public grkap,frkap,frkapq,frkapx |
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285 | public gtlcl,ftlcl,ftlclq,ftlclo,ftlclx |
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286 | public gfuncphys |
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287 | contains |
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288 | !------------------------------------------------------------------------------- |
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289 | subroutine gpvsl |
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290 | !$$$ Subprogram Documentation Block |
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291 | ! |
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292 | ! Subprogram: gpvsl Compute saturation vapor pressure table over liquid |
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293 | ! Author: N Phillips W/NMC2X2 Date: 30 dec 82 |
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294 | ! |
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295 | ! Abstract: Computes saturation vapor pressure table as a function of |
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296 | ! temperature for the table lookup function fpvsl. |
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297 | ! Exact saturation vapor pressures are calculated in subprogram fpvslx. |
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298 | ! The current implementation computes a table with a length |
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299 | ! of 7501 for temperatures ranging from 180. to 330. Kelvin. |
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300 | ! |
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301 | ! Program History Log: |
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302 | ! 91-05-07 Iredell |
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303 | ! 94-12-30 Iredell expand table |
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304 | ! 1999-03-01 Iredell f90 module |
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305 | ! |
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306 | ! Usage: call gpvsl |
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307 | ! |
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308 | ! Subprograms called: |
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309 | ! (fpvslx) inlinable function to compute saturation vapor pressure |
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310 | ! |
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311 | ! Attributes: |
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312 | ! Language: Fortran 90. |
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313 | ! |
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314 | !$$$ |
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315 | implicit none |
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316 | integer jx |
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317 | real(krealfp) xmin,xmax,xinc,x,t |
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318 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
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319 | xmin=180.0_krealfp |
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320 | xmax=330.0_krealfp |
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321 | xinc=(xmax-xmin)/(nxpvsl-1) |
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322 | ! c1xpvsl=1.-xmin/xinc |
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323 | c2xpvsl=1./xinc |
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324 | c1xpvsl=1.-xmin*c2xpvsl |
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325 | do jx=1,nxpvsl |
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326 | x=xmin+(jx-1)*xinc |
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327 | t=x |
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328 | tbpvsl(jx)=fpvslx(t) |
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329 | enddo |
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330 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
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331 | end subroutine |
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332 | !------------------------------------------------------------------------------- |
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333 | ! elemental function fpvsl(t) |
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334 | function fpvsl(t) |
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335 | !$$$ Subprogram Documentation Block |
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336 | ! |
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337 | ! Subprogram: fpvsl Compute saturation vapor pressure over liquid |
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338 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
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339 | ! |
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340 | ! Abstract: Compute saturation vapor pressure from the temperature. |
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341 | ! A linear interpolation is done between values in a lookup table |
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342 | ! computed in gpvsl. See documentation for fpvslx for details. |
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343 | ! Input values outside table range are reset to table extrema. |
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344 | ! The interpolation accuracy is almost 6 decimal places. |
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345 | ! On the Cray, fpvsl is about 4 times faster than exact calculation. |
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346 | ! This function should be expanded inline in the calling routine. |
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347 | ! |
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348 | ! Program History Log: |
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349 | ! 91-05-07 Iredell made into inlinable function |
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350 | ! 94-12-30 Iredell expand table |
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351 | ! 1999-03-01 Iredell f90 module |
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352 | ! |
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353 | ! Usage: pvsl=fpvsl(t) |
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354 | ! |
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355 | ! Input argument list: |
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356 | ! t Real(krealfp) temperature in Kelvin |
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357 | ! |
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358 | ! Output argument list: |
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359 | ! fpvsl Real(krealfp) saturation vapor pressure in Pascals |
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360 | ! |
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361 | ! Attributes: |
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362 | ! Language: Fortran 90. |
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363 | ! |
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364 | !$$$ |
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365 | implicit none |
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366 | real(krealfp) fpvsl |
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367 | real(krealfp),intent(in):: t |
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368 | integer jx |
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369 | real(krealfp) xj |
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370 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
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371 | xj=min(max(c1xpvsl+c2xpvsl*t,1._krealfp),real(nxpvsl,krealfp)) |
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372 | jx=min(xj,nxpvsl-1._krealfp) |
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373 | fpvsl=tbpvsl(jx)+(xj-jx)*(tbpvsl(jx+1)-tbpvsl(jx)) |
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374 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
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375 | end function |
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376 | !------------------------------------------------------------------------------- |
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377 | ! elemental function fpvslq(t) |
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378 | function fpvslq(t) |
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379 | !$$$ Subprogram Documentation Block |
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380 | ! |
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381 | ! Subprogram: fpvslq Compute saturation vapor pressure over liquid |
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382 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
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383 | ! |
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384 | ! Abstract: Compute saturation vapor pressure from the temperature. |
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385 | ! A quadratic interpolation is done between values in a lookup table |
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386 | ! computed in gpvsl. See documentation for fpvslx for details. |
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387 | ! Input values outside table range are reset to table extrema. |
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388 | ! The interpolation accuracy is almost 9 decimal places. |
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389 | ! On the Cray, fpvslq is about 3 times faster than exact calculation. |
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390 | ! This function should be expanded inline in the calling routine. |
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391 | ! |
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392 | ! Program History Log: |
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393 | ! 91-05-07 Iredell made into inlinable function |
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394 | ! 94-12-30 Iredell quadratic interpolation |
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395 | ! 1999-03-01 Iredell f90 module |
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396 | ! |
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397 | ! Usage: pvsl=fpvslq(t) |
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398 | ! |
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399 | ! Input argument list: |
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400 | ! t Real(krealfp) temperature in Kelvin |
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401 | ! |
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402 | ! Output argument list: |
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403 | ! fpvslq Real(krealfp) saturation vapor pressure in Pascals |
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404 | ! |
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405 | ! Attributes: |
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406 | ! Language: Fortran 90. |
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407 | ! |
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408 | !$$$ |
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409 | implicit none |
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410 | real(krealfp) fpvslq |
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411 | real(krealfp),intent(in):: t |
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412 | integer jx |
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413 | real(krealfp) xj,dxj,fj1,fj2,fj3 |
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414 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
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415 | xj=min(max(c1xpvsl+c2xpvsl*t,1._krealfp),real(nxpvsl,krealfp)) |
---|
416 | jx=min(max(nint(xj),2),nxpvsl-1) |
---|
417 | dxj=xj-jx |
---|
418 | fj1=tbpvsl(jx-1) |
---|
419 | fj2=tbpvsl(jx) |
---|
420 | fj3=tbpvsl(jx+1) |
---|
421 | fpvslq=(((fj3+fj1)/2-fj2)*dxj+(fj3-fj1)/2)*dxj+fj2 |
---|
422 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
423 | end function |
---|
424 | !------------------------------------------------------------------------------- |
---|
425 | ! elemental function fpvslx(t) |
---|
426 | function fpvslx(t) |
---|
427 | !$$$ Subprogram Documentation Block |
---|
428 | ! |
---|
429 | ! Subprogram: fpvslx Compute saturation vapor pressure over liquid |
---|
430 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
431 | ! |
---|
432 | ! Abstract: Exactly compute saturation vapor pressure from temperature. |
---|
433 | ! The water model assumes a perfect gas, constant specific heats |
---|
434 | ! for gas and liquid, and neglects the volume of the liquid. |
---|
435 | ! The model does account for the variation of the latent heat |
---|
436 | ! of condensation with temperature. The ice option is not included. |
---|
437 | ! The Clausius-Clapeyron equation is integrated from the triple point |
---|
438 | ! to get the formula |
---|
439 | ! pvsl=con_psat*(tr**xa)*exp(xb*(1.-tr)) |
---|
440 | ! where tr is ttp/t and other values are physical constants. |
---|
441 | ! This function should be expanded inline in the calling routine. |
---|
442 | ! |
---|
443 | ! Program History Log: |
---|
444 | ! 91-05-07 Iredell made into inlinable function |
---|
445 | ! 94-12-30 Iredell exact computation |
---|
446 | ! 1999-03-01 Iredell f90 module |
---|
447 | ! |
---|
448 | ! Usage: pvsl=fpvslx(t) |
---|
449 | ! |
---|
450 | ! Input argument list: |
---|
451 | ! t Real(krealfp) temperature in Kelvin |
---|
452 | ! |
---|
453 | ! Output argument list: |
---|
454 | ! fpvslx Real(krealfp) saturation vapor pressure in Pascals |
---|
455 | ! |
---|
456 | ! Attributes: |
---|
457 | ! Language: Fortran 90. |
---|
458 | ! |
---|
459 | !$$$ |
---|
460 | implicit none |
---|
461 | real(krealfp) fpvslx |
---|
462 | real(krealfp),intent(in):: t |
---|
463 | real(krealfp),parameter:: dldt=con_cvap-con_cliq |
---|
464 | real(krealfp),parameter:: heat=con_hvap |
---|
465 | real(krealfp),parameter:: xpona=-dldt/con_rv |
---|
466 | real(krealfp),parameter:: xponb=-dldt/con_rv+heat/(con_rv*con_ttp) |
---|
467 | real(krealfp) tr |
---|
468 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
469 | tr=con_ttp/t |
---|
470 | fpvslx=con_psat*(tr**xpona)*exp(xponb*(1.-tr)) |
---|
471 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
472 | end function |
---|
473 | !------------------------------------------------------------------------------- |
---|
474 | subroutine gpvsi |
---|
475 | !$$$ Subprogram Documentation Block |
---|
476 | ! |
---|
477 | ! Subprogram: gpvsi Compute saturation vapor pressure table over ice |
---|
478 | ! Author: N Phillips W/NMC2X2 Date: 30 dec 82 |
---|
479 | ! |
---|
480 | ! Abstract: Computes saturation vapor pressure table as a function of |
---|
481 | ! temperature for the table lookup function fpvsi. |
---|
482 | ! Exact saturation vapor pressures are calculated in subprogram fpvsix. |
---|
483 | ! The current implementation computes a table with a length |
---|
484 | ! of 7501 for temperatures ranging from 180. to 330. Kelvin. |
---|
485 | ! |
---|
486 | ! Program History Log: |
---|
487 | ! 91-05-07 Iredell |
---|
488 | ! 94-12-30 Iredell expand table |
---|
489 | ! 1999-03-01 Iredell f90 module |
---|
490 | ! 2001-02-26 Iredell ice phase |
---|
491 | ! |
---|
492 | ! Usage: call gpvsi |
---|
493 | ! |
---|
494 | ! Subprograms called: |
---|
495 | ! (fpvsix) inlinable function to compute saturation vapor pressure |
---|
496 | ! |
---|
497 | ! Attributes: |
---|
498 | ! Language: Fortran 90. |
---|
499 | ! |
---|
500 | !$$$ |
---|
501 | implicit none |
---|
502 | integer jx |
---|
503 | real(krealfp) xmin,xmax,xinc,x,t |
---|
504 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
505 | xmin=180.0_krealfp |
---|
506 | xmax=330.0_krealfp |
---|
507 | xinc=(xmax-xmin)/(nxpvsi-1) |
---|
508 | ! c1xpvsi=1.-xmin/xinc |
---|
509 | c2xpvsi=1./xinc |
---|
510 | c1xpvsi=1.-xmin*c2xpvsi |
---|
511 | do jx=1,nxpvsi |
---|
512 | x=xmin+(jx-1)*xinc |
---|
513 | t=x |
---|
514 | tbpvsi(jx)=fpvsix(t) |
---|
515 | enddo |
---|
516 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
517 | end subroutine |
---|
518 | !------------------------------------------------------------------------------- |
---|
519 | ! elemental function fpvsi(t) |
---|
520 | function fpvsi(t) |
---|
521 | !$$$ Subprogram Documentation Block |
---|
522 | ! |
---|
523 | ! Subprogram: fpvsi Compute saturation vapor pressure over ice |
---|
524 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
525 | ! |
---|
526 | ! Abstract: Compute saturation vapor pressure from the temperature. |
---|
527 | ! A linear interpolation is done between values in a lookup table |
---|
528 | ! computed in gpvsi. See documentation for fpvsix for details. |
---|
529 | ! Input values outside table range are reset to table extrema. |
---|
530 | ! The interpolation accuracy is almost 6 decimal places. |
---|
531 | ! On the Cray, fpvsi is about 4 times faster than exact calculation. |
---|
532 | ! This function should be expanded inline in the calling routine. |
---|
533 | ! |
---|
534 | ! Program History Log: |
---|
535 | ! 91-05-07 Iredell made into inlinable function |
---|
536 | ! 94-12-30 Iredell expand table |
---|
537 | ! 1999-03-01 Iredell f90 module |
---|
538 | ! 2001-02-26 Iredell ice phase |
---|
539 | ! |
---|
540 | ! Usage: pvsi=fpvsi(t) |
---|
541 | ! |
---|
542 | ! Input argument list: |
---|
543 | ! t Real(krealfp) temperature in Kelvin |
---|
544 | ! |
---|
545 | ! Output argument list: |
---|
546 | ! fpvsi Real(krealfp) saturation vapor pressure in Pascals |
---|
547 | ! |
---|
548 | ! Attributes: |
---|
549 | ! Language: Fortran 90. |
---|
550 | ! |
---|
551 | !$$$ |
---|
552 | implicit none |
---|
553 | real(krealfp) fpvsi |
---|
554 | real(krealfp),intent(in):: t |
---|
555 | integer jx |
---|
556 | real(krealfp) xj |
---|
557 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
558 | xj=min(max(c1xpvsi+c2xpvsi*t,1._krealfp),real(nxpvsi,krealfp)) |
---|
559 | jx=min(xj,nxpvsi-1._krealfp) |
---|
560 | fpvsi=tbpvsi(jx)+(xj-jx)*(tbpvsi(jx+1)-tbpvsi(jx)) |
---|
561 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
562 | end function |
---|
563 | !------------------------------------------------------------------------------- |
---|
564 | ! elemental function fpvsiq(t) |
---|
565 | function fpvsiq(t) |
---|
566 | !$$$ Subprogram Documentation Block |
---|
567 | ! |
---|
568 | ! Subprogram: fpvsiq Compute saturation vapor pressure over ice |
---|
569 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
570 | ! |
---|
571 | ! Abstract: Compute saturation vapor pressure from the temperature. |
---|
572 | ! A quadratic interpolation is done between values in a lookup table |
---|
573 | ! computed in gpvsi. See documentation for fpvsix for details. |
---|
574 | ! Input values outside table range are reset to table extrema. |
---|
575 | ! The interpolation accuracy is almost 9 decimal places. |
---|
576 | ! On the Cray, fpvsiq is about 3 times faster than exact calculation. |
---|
577 | ! This function should be expanded inline in the calling routine. |
---|
578 | ! |
---|
579 | ! Program History Log: |
---|
580 | ! 91-05-07 Iredell made into inlinable function |
---|
581 | ! 94-12-30 Iredell quadratic interpolation |
---|
582 | ! 1999-03-01 Iredell f90 module |
---|
583 | ! 2001-02-26 Iredell ice phase |
---|
584 | ! |
---|
585 | ! Usage: pvsi=fpvsiq(t) |
---|
586 | ! |
---|
587 | ! Input argument list: |
---|
588 | ! t Real(krealfp) temperature in Kelvin |
---|
589 | ! |
---|
590 | ! Output argument list: |
---|
591 | ! fpvsiq Real(krealfp) saturation vapor pressure in Pascals |
---|
592 | ! |
---|
593 | ! Attributes: |
---|
594 | ! Language: Fortran 90. |
---|
595 | ! |
---|
596 | !$$$ |
---|
597 | implicit none |
---|
598 | real(krealfp) fpvsiq |
---|
599 | real(krealfp),intent(in):: t |
---|
600 | integer jx |
---|
601 | real(krealfp) xj,dxj,fj1,fj2,fj3 |
---|
602 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
603 | xj=min(max(c1xpvsi+c2xpvsi*t,1._krealfp),real(nxpvsi,krealfp)) |
---|
604 | jx=min(max(nint(xj),2),nxpvsi-1) |
---|
605 | dxj=xj-jx |
---|
606 | fj1=tbpvsi(jx-1) |
---|
607 | fj2=tbpvsi(jx) |
---|
608 | fj3=tbpvsi(jx+1) |
---|
609 | fpvsiq=(((fj3+fj1)/2-fj2)*dxj+(fj3-fj1)/2)*dxj+fj2 |
---|
610 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
611 | end function |
---|
612 | !------------------------------------------------------------------------------- |
---|
613 | ! elemental function fpvsix(t) |
---|
614 | function fpvsix(t) |
---|
615 | !$$$ Subprogram Documentation Block |
---|
616 | ! |
---|
617 | ! Subprogram: fpvsix Compute saturation vapor pressure over ice |
---|
618 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
619 | ! |
---|
620 | ! Abstract: Exactly compute saturation vapor pressure from temperature. |
---|
621 | ! The water model assumes a perfect gas, constant specific heats |
---|
622 | ! for gas and ice, and neglects the volume of the ice. |
---|
623 | ! The model does account for the variation of the latent heat |
---|
624 | ! of condensation with temperature. The liquid option is not included. |
---|
625 | ! The Clausius-Clapeyron equation is integrated from the triple point |
---|
626 | ! to get the formula |
---|
627 | ! pvsi=con_psat*(tr**xa)*exp(xb*(1.-tr)) |
---|
628 | ! where tr is ttp/t and other values are physical constants. |
---|
629 | ! This function should be expanded inline in the calling routine. |
---|
630 | ! |
---|
631 | ! Program History Log: |
---|
632 | ! 91-05-07 Iredell made into inlinable function |
---|
633 | ! 94-12-30 Iredell exact computation |
---|
634 | ! 1999-03-01 Iredell f90 module |
---|
635 | ! 2001-02-26 Iredell ice phase |
---|
636 | ! |
---|
637 | ! Usage: pvsi=fpvsix(t) |
---|
638 | ! |
---|
639 | ! Input argument list: |
---|
640 | ! t Real(krealfp) temperature in Kelvin |
---|
641 | ! |
---|
642 | ! Output argument list: |
---|
643 | ! fpvsix Real(krealfp) saturation vapor pressure in Pascals |
---|
644 | ! |
---|
645 | ! Attributes: |
---|
646 | ! Language: Fortran 90. |
---|
647 | ! |
---|
648 | !$$$ |
---|
649 | implicit none |
---|
650 | real(krealfp) fpvsix |
---|
651 | real(krealfp),intent(in):: t |
---|
652 | real(krealfp),parameter:: dldt=con_cvap-con_csol |
---|
653 | real(krealfp),parameter:: heat=con_hvap+con_hfus |
---|
654 | real(krealfp),parameter:: xpona=-dldt/con_rv |
---|
655 | real(krealfp),parameter:: xponb=-dldt/con_rv+heat/(con_rv*con_ttp) |
---|
656 | real(krealfp) tr |
---|
657 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
658 | tr=con_ttp/t |
---|
659 | fpvsix=con_psat*(tr**xpona)*exp(xponb*(1.-tr)) |
---|
660 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
661 | end function |
---|
662 | !------------------------------------------------------------------------------- |
---|
663 | subroutine gpvs |
---|
664 | !$$$ Subprogram Documentation Block |
---|
665 | ! |
---|
666 | ! Subprogram: gpvs Compute saturation vapor pressure table |
---|
667 | ! Author: N Phillips W/NMC2X2 Date: 30 dec 82 |
---|
668 | ! |
---|
669 | ! Abstract: Computes saturation vapor pressure table as a function of |
---|
670 | ! temperature for the table lookup function fpvs. |
---|
671 | ! Exact saturation vapor pressures are calculated in subprogram fpvsx. |
---|
672 | ! The current implementation computes a table with a length |
---|
673 | ! of 7501 for temperatures ranging from 180. to 330. Kelvin. |
---|
674 | ! |
---|
675 | ! Program History Log: |
---|
676 | ! 91-05-07 Iredell |
---|
677 | ! 94-12-30 Iredell expand table |
---|
678 | ! 1999-03-01 Iredell f90 module |
---|
679 | ! 2001-02-26 Iredell ice phase |
---|
680 | ! |
---|
681 | ! Usage: call gpvs |
---|
682 | ! |
---|
683 | ! Subprograms called: |
---|
684 | ! (fpvsx) inlinable function to compute saturation vapor pressure |
---|
685 | ! |
---|
686 | ! Attributes: |
---|
687 | ! Language: Fortran 90. |
---|
688 | ! |
---|
689 | !$$$ |
---|
690 | implicit none |
---|
691 | integer jx |
---|
692 | real(krealfp) xmin,xmax,xinc,x,t |
---|
693 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
694 | xmin=180.0_krealfp |
---|
695 | xmax=330.0_krealfp |
---|
696 | xinc=(xmax-xmin)/(nxpvs-1) |
---|
697 | ! c1xpvs=1.-xmin/xinc |
---|
698 | c2xpvs=1./xinc |
---|
699 | c1xpvs=1.-xmin*c2xpvs |
---|
700 | do jx=1,nxpvs |
---|
701 | x=xmin+(jx-1)*xinc |
---|
702 | t=x |
---|
703 | tbpvs(jx)=fpvsx(t) |
---|
704 | enddo |
---|
705 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
706 | end subroutine |
---|
707 | !------------------------------------------------------------------------------- |
---|
708 | ! elemental function fpvs(t) |
---|
709 | function fpvs(t) |
---|
710 | !$$$ Subprogram Documentation Block |
---|
711 | ! |
---|
712 | ! Subprogram: fpvs Compute saturation vapor pressure |
---|
713 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
714 | ! |
---|
715 | ! Abstract: Compute saturation vapor pressure from the temperature. |
---|
716 | ! A linear interpolation is done between values in a lookup table |
---|
717 | ! computed in gpvs. See documentation for fpvsx for details. |
---|
718 | ! Input values outside table range are reset to table extrema. |
---|
719 | ! The interpolation accuracy is almost 6 decimal places. |
---|
720 | ! On the Cray, fpvs is about 4 times faster than exact calculation. |
---|
721 | ! This function should be expanded inline in the calling routine. |
---|
722 | ! |
---|
723 | ! Program History Log: |
---|
724 | ! 91-05-07 Iredell made into inlinable function |
---|
725 | ! 94-12-30 Iredell expand table |
---|
726 | ! 1999-03-01 Iredell f90 module |
---|
727 | ! 2001-02-26 Iredell ice phase |
---|
728 | ! |
---|
729 | ! Usage: pvs=fpvs(t) |
---|
730 | ! |
---|
731 | ! Input argument list: |
---|
732 | ! t Real(krealfp) temperature in Kelvin |
---|
733 | ! |
---|
734 | ! Output argument list: |
---|
735 | ! fpvs Real(krealfp) saturation vapor pressure in Pascals |
---|
736 | ! |
---|
737 | ! Attributes: |
---|
738 | ! Language: Fortran 90. |
---|
739 | ! |
---|
740 | !$$$ |
---|
741 | implicit none |
---|
742 | real(krealfp) fpvs |
---|
743 | real(krealfp),intent(in):: t |
---|
744 | integer jx |
---|
745 | real(krealfp) xj |
---|
746 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
747 | xj=min(max(c1xpvs+c2xpvs*t,1._krealfp),real(nxpvs,krealfp)) |
---|
748 | jx=min(xj,nxpvs-1._krealfp) |
---|
749 | fpvs=tbpvs(jx)+(xj-jx)*(tbpvs(jx+1)-tbpvs(jx)) |
---|
750 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
751 | end function |
---|
752 | !------------------------------------------------------------------------------- |
---|
753 | ! elemental function fpvsq(t) |
---|
754 | function fpvsq(t) |
---|
755 | !$$$ Subprogram Documentation Block |
---|
756 | ! |
---|
757 | ! Subprogram: fpvsq Compute saturation vapor pressure |
---|
758 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
759 | ! |
---|
760 | ! Abstract: Compute saturation vapor pressure from the temperature. |
---|
761 | ! A quadratic interpolation is done between values in a lookup table |
---|
762 | ! computed in gpvs. See documentation for fpvsx for details. |
---|
763 | ! Input values outside table range are reset to table extrema. |
---|
764 | ! The interpolation accuracy is almost 9 decimal places. |
---|
765 | ! On the Cray, fpvsq is about 3 times faster than exact calculation. |
---|
766 | ! This function should be expanded inline in the calling routine. |
---|
767 | ! |
---|
768 | ! Program History Log: |
---|
769 | ! 91-05-07 Iredell made into inlinable function |
---|
770 | ! 94-12-30 Iredell quadratic interpolation |
---|
771 | ! 1999-03-01 Iredell f90 module |
---|
772 | ! 2001-02-26 Iredell ice phase |
---|
773 | ! |
---|
774 | ! Usage: pvs=fpvsq(t) |
---|
775 | ! |
---|
776 | ! Input argument list: |
---|
777 | ! t Real(krealfp) temperature in Kelvin |
---|
778 | ! |
---|
779 | ! Output argument list: |
---|
780 | ! fpvsq Real(krealfp) saturation vapor pressure in Pascals |
---|
781 | ! |
---|
782 | ! Attributes: |
---|
783 | ! Language: Fortran 90. |
---|
784 | ! |
---|
785 | !$$$ |
---|
786 | implicit none |
---|
787 | real(krealfp) fpvsq |
---|
788 | real(krealfp),intent(in):: t |
---|
789 | integer jx |
---|
790 | real(krealfp) xj,dxj,fj1,fj2,fj3 |
---|
791 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
792 | xj=min(max(c1xpvs+c2xpvs*t,1._krealfp),real(nxpvs,krealfp)) |
---|
793 | jx=min(max(nint(xj),2),nxpvs-1) |
---|
794 | dxj=xj-jx |
---|
795 | fj1=tbpvs(jx-1) |
---|
796 | fj2=tbpvs(jx) |
---|
797 | fj3=tbpvs(jx+1) |
---|
798 | fpvsq=(((fj3+fj1)/2-fj2)*dxj+(fj3-fj1)/2)*dxj+fj2 |
---|
799 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
800 | end function |
---|
801 | !------------------------------------------------------------------------------- |
---|
802 | ! elemental function fpvsx(t) |
---|
803 | function fpvsx(t) |
---|
804 | !$$$ Subprogram Documentation Block |
---|
805 | ! |
---|
806 | ! Subprogram: fpvsx Compute saturation vapor pressure |
---|
807 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
808 | ! |
---|
809 | ! Abstract: Exactly compute saturation vapor pressure from temperature. |
---|
810 | ! The saturation vapor pressure over either liquid and ice is computed |
---|
811 | ! over liquid for temperatures above the triple point, |
---|
812 | ! over ice for temperatures 20 degress below the triple point, |
---|
813 | ! and a linear combination of the two for temperatures in between. |
---|
814 | ! The water model assumes a perfect gas, constant specific heats |
---|
815 | ! for gas, liquid and ice, and neglects the volume of the condensate. |
---|
816 | ! The model does account for the variation of the latent heat |
---|
817 | ! of condensation and sublimation with temperature. |
---|
818 | ! The Clausius-Clapeyron equation is integrated from the triple point |
---|
819 | ! to get the formula |
---|
820 | ! pvsl=con_psat*(tr**xa)*exp(xb*(1.-tr)) |
---|
821 | ! where tr is ttp/t and other values are physical constants. |
---|
822 | ! The reference for this computation is Emanuel(1994), pages 116-117. |
---|
823 | ! This function should be expanded inline in the calling routine. |
---|
824 | ! |
---|
825 | ! Program History Log: |
---|
826 | ! 91-05-07 Iredell made into inlinable function |
---|
827 | ! 94-12-30 Iredell exact computation |
---|
828 | ! 1999-03-01 Iredell f90 module |
---|
829 | ! 2001-02-26 Iredell ice phase |
---|
830 | ! |
---|
831 | ! Usage: pvs=fpvsx(t) |
---|
832 | ! |
---|
833 | ! Input argument list: |
---|
834 | ! t Real(krealfp) temperature in Kelvin |
---|
835 | ! |
---|
836 | ! Output argument list: |
---|
837 | ! fpvsx Real(krealfp) saturation vapor pressure in Pascals |
---|
838 | ! |
---|
839 | ! Attributes: |
---|
840 | ! Language: Fortran 90. |
---|
841 | ! |
---|
842 | !$$$ |
---|
843 | implicit none |
---|
844 | real(krealfp) fpvsx |
---|
845 | real(krealfp),intent(in):: t |
---|
846 | real(krealfp),parameter:: tliq=con_ttp |
---|
847 | real(krealfp),parameter:: tice=con_ttp-20.0 |
---|
848 | real(krealfp),parameter:: dldtl=con_cvap-con_cliq |
---|
849 | real(krealfp),parameter:: heatl=con_hvap |
---|
850 | real(krealfp),parameter:: xponal=-dldtl/con_rv |
---|
851 | real(krealfp),parameter:: xponbl=-dldtl/con_rv+heatl/(con_rv*con_ttp) |
---|
852 | real(krealfp),parameter:: dldti=con_cvap-con_csol |
---|
853 | real(krealfp),parameter:: heati=con_hvap+con_hfus |
---|
854 | real(krealfp),parameter:: xponai=-dldti/con_rv |
---|
855 | real(krealfp),parameter:: xponbi=-dldti/con_rv+heati/(con_rv*con_ttp) |
---|
856 | real(krealfp) tr,w,pvl,pvi |
---|
857 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
858 | tr=con_ttp/t |
---|
859 | if(t.ge.tliq) then |
---|
860 | fpvsx=con_psat*(tr**xponal)*exp(xponbl*(1.-tr)) |
---|
861 | elseif(t.lt.tice) then |
---|
862 | fpvsx=con_psat*(tr**xponai)*exp(xponbi*(1.-tr)) |
---|
863 | else |
---|
864 | w=(t-tice)/(tliq-tice) |
---|
865 | pvl=con_psat*(tr**xponal)*exp(xponbl*(1.-tr)) |
---|
866 | pvi=con_psat*(tr**xponai)*exp(xponbi*(1.-tr)) |
---|
867 | fpvsx=w*pvl+(1.-w)*pvi |
---|
868 | endif |
---|
869 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
870 | end function |
---|
871 | !------------------------------------------------------------------------------- |
---|
872 | subroutine gtdpl |
---|
873 | !$$$ Subprogram Documentation Block |
---|
874 | ! |
---|
875 | ! Subprogram: gtdpl Compute dewpoint temperature over liquid table |
---|
876 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
877 | ! |
---|
878 | ! Abstract: Compute dewpoint temperature table as a function of |
---|
879 | ! vapor pressure for inlinable function ftdpl. |
---|
880 | ! Exact dewpoint temperatures are calculated in subprogram ftdplxg. |
---|
881 | ! The current implementation computes a table with a length |
---|
882 | ! of 5001 for vapor pressures ranging from 1 to 10001 Pascals |
---|
883 | ! giving a dewpoint temperature range of 208 to 319 Kelvin. |
---|
884 | ! |
---|
885 | ! Program History Log: |
---|
886 | ! 91-05-07 Iredell |
---|
887 | ! 94-12-30 Iredell expand table |
---|
888 | ! 1999-03-01 Iredell f90 module |
---|
889 | ! |
---|
890 | ! Usage: call gtdpl |
---|
891 | ! |
---|
892 | ! Subprograms called: |
---|
893 | ! (ftdplxg) inlinable function to compute dewpoint temperature over liquid |
---|
894 | ! |
---|
895 | ! Attributes: |
---|
896 | ! Language: Fortran 90. |
---|
897 | ! |
---|
898 | !$$$ |
---|
899 | implicit none |
---|
900 | integer jx |
---|
901 | real(krealfp) xmin,xmax,xinc,t,x,pv |
---|
902 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
903 | xmin=1 |
---|
904 | xmax=10001 |
---|
905 | xinc=(xmax-xmin)/(nxtdpl-1) |
---|
906 | c1xtdpl=1.-xmin/xinc |
---|
907 | c2xtdpl=1./xinc |
---|
908 | t=208.0 |
---|
909 | do jx=1,nxtdpl |
---|
910 | x=xmin+(jx-1)*xinc |
---|
911 | pv=x |
---|
912 | t=ftdplxg(t,pv) |
---|
913 | tbtdpl(jx)=t |
---|
914 | enddo |
---|
915 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
916 | end subroutine |
---|
917 | !------------------------------------------------------------------------------- |
---|
918 | ! elemental function ftdpl(pv) |
---|
919 | function ftdpl(pv) |
---|
920 | !$$$ Subprogram Documentation Block |
---|
921 | ! |
---|
922 | ! Subprogram: ftdpl Compute dewpoint temperature over liquid |
---|
923 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
924 | ! |
---|
925 | ! Abstract: Compute dewpoint temperature from vapor pressure. |
---|
926 | ! A linear interpolation is done between values in a lookup table |
---|
927 | ! computed in gtdpl. See documentation for ftdplxg for details. |
---|
928 | ! Input values outside table range are reset to table extrema. |
---|
929 | ! The interpolation accuracy is better than 0.0005 Kelvin |
---|
930 | ! for dewpoint temperatures greater than 250 Kelvin, |
---|
931 | ! but decreases to 0.02 Kelvin for a dewpoint around 230 Kelvin. |
---|
932 | ! On the Cray, ftdpl is about 75 times faster than exact calculation. |
---|
933 | ! This function should be expanded inline in the calling routine. |
---|
934 | ! |
---|
935 | ! Program History Log: |
---|
936 | ! 91-05-07 Iredell made into inlinable function |
---|
937 | ! 94-12-30 Iredell expand table |
---|
938 | ! 1999-03-01 Iredell f90 module |
---|
939 | ! |
---|
940 | ! Usage: tdpl=ftdpl(pv) |
---|
941 | ! |
---|
942 | ! Input argument list: |
---|
943 | ! pv Real(krealfp) vapor pressure in Pascals |
---|
944 | ! |
---|
945 | ! Output argument list: |
---|
946 | ! ftdpl Real(krealfp) dewpoint temperature in Kelvin |
---|
947 | ! |
---|
948 | ! Attributes: |
---|
949 | ! Language: Fortran 90. |
---|
950 | ! |
---|
951 | !$$$ |
---|
952 | implicit none |
---|
953 | real(krealfp) ftdpl |
---|
954 | real(krealfp),intent(in):: pv |
---|
955 | integer jx |
---|
956 | real(krealfp) xj |
---|
957 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
958 | xj=min(max(c1xtdpl+c2xtdpl*pv,1._krealfp),real(nxtdpl,krealfp)) |
---|
959 | jx=min(xj,nxtdpl-1._krealfp) |
---|
960 | ftdpl=tbtdpl(jx)+(xj-jx)*(tbtdpl(jx+1)-tbtdpl(jx)) |
---|
961 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
962 | end function |
---|
963 | !------------------------------------------------------------------------------- |
---|
964 | ! elemental function ftdplq(pv) |
---|
965 | function ftdplq(pv) |
---|
966 | !$$$ Subprogram Documentation Block |
---|
967 | ! |
---|
968 | ! Subprogram: ftdplq Compute dewpoint temperature over liquid |
---|
969 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
970 | ! |
---|
971 | ! Abstract: Compute dewpoint temperature from vapor pressure. |
---|
972 | ! A quadratic interpolation is done between values in a lookup table |
---|
973 | ! computed in gtdpl. see documentation for ftdplxg for details. |
---|
974 | ! Input values outside table range are reset to table extrema. |
---|
975 | ! the interpolation accuracy is better than 0.00001 Kelvin |
---|
976 | ! for dewpoint temperatures greater than 250 Kelvin, |
---|
977 | ! but decreases to 0.002 Kelvin for a dewpoint around 230 Kelvin. |
---|
978 | ! On the Cray, ftdplq is about 60 times faster than exact calculation. |
---|
979 | ! This function should be expanded inline in the calling routine. |
---|
980 | ! |
---|
981 | ! Program History Log: |
---|
982 | ! 91-05-07 Iredell made into inlinable function |
---|
983 | ! 94-12-30 Iredell quadratic interpolation |
---|
984 | ! 1999-03-01 Iredell f90 module |
---|
985 | ! |
---|
986 | ! Usage: tdpl=ftdplq(pv) |
---|
987 | ! |
---|
988 | ! Input argument list: |
---|
989 | ! pv Real(krealfp) vapor pressure in Pascals |
---|
990 | ! |
---|
991 | ! Output argument list: |
---|
992 | ! ftdplq Real(krealfp) dewpoint temperature in Kelvin |
---|
993 | ! |
---|
994 | ! Attributes: |
---|
995 | ! Language: Fortran 90. |
---|
996 | ! |
---|
997 | !$$$ |
---|
998 | implicit none |
---|
999 | real(krealfp) ftdplq |
---|
1000 | real(krealfp),intent(in):: pv |
---|
1001 | integer jx |
---|
1002 | real(krealfp) xj,dxj,fj1,fj2,fj3 |
---|
1003 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1004 | xj=min(max(c1xtdpl+c2xtdpl*pv,1._krealfp),real(nxtdpl,krealfp)) |
---|
1005 | jx=min(max(nint(xj),2),nxtdpl-1) |
---|
1006 | dxj=xj-jx |
---|
1007 | fj1=tbtdpl(jx-1) |
---|
1008 | fj2=tbtdpl(jx) |
---|
1009 | fj3=tbtdpl(jx+1) |
---|
1010 | ftdplq=(((fj3+fj1)/2-fj2)*dxj+(fj3-fj1)/2)*dxj+fj2 |
---|
1011 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1012 | end function |
---|
1013 | !------------------------------------------------------------------------------- |
---|
1014 | ! elemental function ftdplx(pv) |
---|
1015 | function ftdplx(pv) |
---|
1016 | !$$$ Subprogram Documentation Block |
---|
1017 | ! |
---|
1018 | ! Subprogram: ftdplx Compute dewpoint temperature over liquid |
---|
1019 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
1020 | ! |
---|
1021 | ! Abstract: exactly compute dewpoint temperature from vapor pressure. |
---|
1022 | ! An approximate dewpoint temperature for function ftdplxg |
---|
1023 | ! is obtained using ftdpl so gtdpl must be already called. |
---|
1024 | ! See documentation for ftdplxg for details. |
---|
1025 | ! |
---|
1026 | ! Program History Log: |
---|
1027 | ! 91-05-07 Iredell made into inlinable function |
---|
1028 | ! 94-12-30 Iredell exact computation |
---|
1029 | ! 1999-03-01 Iredell f90 module |
---|
1030 | ! |
---|
1031 | ! Usage: tdpl=ftdplx(pv) |
---|
1032 | ! |
---|
1033 | ! Input argument list: |
---|
1034 | ! pv Real(krealfp) vapor pressure in Pascals |
---|
1035 | ! |
---|
1036 | ! Output argument list: |
---|
1037 | ! ftdplx Real(krealfp) dewpoint temperature in Kelvin |
---|
1038 | ! |
---|
1039 | ! Subprograms called: |
---|
1040 | ! (ftdpl) inlinable function to compute dewpoint temperature over liquid |
---|
1041 | ! (ftdplxg) inlinable function to compute dewpoint temperature over liquid |
---|
1042 | ! |
---|
1043 | ! Attributes: |
---|
1044 | ! Language: Fortran 90. |
---|
1045 | ! |
---|
1046 | !$$$ |
---|
1047 | implicit none |
---|
1048 | real(krealfp) ftdplx |
---|
1049 | real(krealfp),intent(in):: pv |
---|
1050 | real(krealfp) tg |
---|
1051 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1052 | tg=ftdpl(pv) |
---|
1053 | ftdplx=ftdplxg(tg,pv) |
---|
1054 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1055 | end function |
---|
1056 | !------------------------------------------------------------------------------- |
---|
1057 | ! elemental function ftdplxg(tg,pv) |
---|
1058 | function ftdplxg(tg,pv) |
---|
1059 | !$$$ Subprogram Documentation Block |
---|
1060 | ! |
---|
1061 | ! Subprogram: ftdplxg Compute dewpoint temperature over liquid |
---|
1062 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
1063 | ! |
---|
1064 | ! Abstract: Exactly compute dewpoint temperature from vapor pressure. |
---|
1065 | ! A guess dewpoint temperature must be provided. |
---|
1066 | ! The water model assumes a perfect gas, constant specific heats |
---|
1067 | ! for gas and liquid, and neglects the volume of the liquid. |
---|
1068 | ! The model does account for the variation of the latent heat |
---|
1069 | ! of condensation with temperature. The ice option is not included. |
---|
1070 | ! The Clausius-Clapeyron equation is integrated from the triple point |
---|
1071 | ! to get the formula |
---|
1072 | ! pvs=con_psat*(tr**xa)*exp(xb*(1.-tr)) |
---|
1073 | ! where tr is ttp/t and other values are physical constants. |
---|
1074 | ! The formula is inverted by iterating Newtonian approximations |
---|
1075 | ! for each pvs until t is found to within 1.e-6 Kelvin. |
---|
1076 | ! This function can be expanded inline in the calling routine. |
---|
1077 | ! |
---|
1078 | ! Program History Log: |
---|
1079 | ! 91-05-07 Iredell made into inlinable function |
---|
1080 | ! 94-12-30 Iredell exact computation |
---|
1081 | ! 1999-03-01 Iredell f90 module |
---|
1082 | ! |
---|
1083 | ! Usage: tdpl=ftdplxg(tg,pv) |
---|
1084 | ! |
---|
1085 | ! Input argument list: |
---|
1086 | ! tg Real(krealfp) guess dewpoint temperature in Kelvin |
---|
1087 | ! pv Real(krealfp) vapor pressure in Pascals |
---|
1088 | ! |
---|
1089 | ! Output argument list: |
---|
1090 | ! ftdplxg Real(krealfp) dewpoint temperature in Kelvin |
---|
1091 | ! |
---|
1092 | ! Attributes: |
---|
1093 | ! Language: Fortran 90. |
---|
1094 | ! |
---|
1095 | !$$$ |
---|
1096 | implicit none |
---|
1097 | real(krealfp) ftdplxg |
---|
1098 | real(krealfp),intent(in):: tg,pv |
---|
1099 | real(krealfp),parameter:: terrm=1.e-6 |
---|
1100 | real(krealfp),parameter:: dldt=con_cvap-con_cliq |
---|
1101 | real(krealfp),parameter:: heat=con_hvap |
---|
1102 | real(krealfp),parameter:: xpona=-dldt/con_rv |
---|
1103 | real(krealfp),parameter:: xponb=-dldt/con_rv+heat/(con_rv*con_ttp) |
---|
1104 | real(krealfp) t,tr,pvt,el,dpvt,terr |
---|
1105 | integer i |
---|
1106 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1107 | t=tg |
---|
1108 | do i=1,100 |
---|
1109 | tr=con_ttp/t |
---|
1110 | pvt=con_psat*(tr**xpona)*exp(xponb*(1.-tr)) |
---|
1111 | el=heat+dldt*(t-con_ttp) |
---|
1112 | dpvt=el*pvt/(con_rv*t**2) |
---|
1113 | terr=(pvt-pv)/dpvt |
---|
1114 | t=t-terr |
---|
1115 | if(abs(terr).le.terrm) exit |
---|
1116 | enddo |
---|
1117 | ftdplxg=t |
---|
1118 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1119 | end function |
---|
1120 | !------------------------------------------------------------------------------- |
---|
1121 | subroutine gtdpi |
---|
1122 | !$$$ Subprogram Documentation Block |
---|
1123 | ! |
---|
1124 | ! Subprogram: gtdpi Compute dewpoint temperature over ice table |
---|
1125 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
1126 | ! |
---|
1127 | ! Abstract: Compute dewpoint temperature table as a function of |
---|
1128 | ! vapor pressure for inlinable function ftdpi. |
---|
1129 | ! Exact dewpoint temperatures are calculated in subprogram ftdpixg. |
---|
1130 | ! The current implementation computes a table with a length |
---|
1131 | ! of 5001 for vapor pressures ranging from 0.1 to 1000.1 Pascals |
---|
1132 | ! giving a dewpoint temperature range of 197 to 279 Kelvin. |
---|
1133 | ! |
---|
1134 | ! Program History Log: |
---|
1135 | ! 91-05-07 Iredell |
---|
1136 | ! 94-12-30 Iredell expand table |
---|
1137 | ! 1999-03-01 Iredell f90 module |
---|
1138 | ! 2001-02-26 Iredell ice phase |
---|
1139 | ! |
---|
1140 | ! Usage: call gtdpi |
---|
1141 | ! |
---|
1142 | ! Subprograms called: |
---|
1143 | ! (ftdpixg) inlinable function to compute dewpoint temperature over ice |
---|
1144 | ! |
---|
1145 | ! Attributes: |
---|
1146 | ! Language: Fortran 90. |
---|
1147 | ! |
---|
1148 | !$$$ |
---|
1149 | implicit none |
---|
1150 | integer jx |
---|
1151 | real(krealfp) xmin,xmax,xinc,t,x,pv |
---|
1152 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1153 | xmin=0.1 |
---|
1154 | xmax=1000.1 |
---|
1155 | xinc=(xmax-xmin)/(nxtdpi-1) |
---|
1156 | c1xtdpi=1.-xmin/xinc |
---|
1157 | c2xtdpi=1./xinc |
---|
1158 | t=197.0 |
---|
1159 | do jx=1,nxtdpi |
---|
1160 | x=xmin+(jx-1)*xinc |
---|
1161 | pv=x |
---|
1162 | t=ftdpixg(t,pv) |
---|
1163 | tbtdpi(jx)=t |
---|
1164 | enddo |
---|
1165 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1166 | end subroutine |
---|
1167 | !------------------------------------------------------------------------------- |
---|
1168 | ! elemental function ftdpi(pv) |
---|
1169 | function ftdpi(pv) |
---|
1170 | !$$$ Subprogram Documentation Block |
---|
1171 | ! |
---|
1172 | ! Subprogram: ftdpi Compute dewpoint temperature over ice |
---|
1173 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
1174 | ! |
---|
1175 | ! Abstract: Compute dewpoint temperature from vapor pressure. |
---|
1176 | ! A linear interpolation is done between values in a lookup table |
---|
1177 | ! computed in gtdpi. See documentation for ftdpixg for details. |
---|
1178 | ! Input values outside table range are reset to table extrema. |
---|
1179 | ! The interpolation accuracy is better than 0.0005 Kelvin |
---|
1180 | ! for dewpoint temperatures greater than 250 Kelvin, |
---|
1181 | ! but decreases to 0.02 Kelvin for a dewpoint around 230 Kelvin. |
---|
1182 | ! On the Cray, ftdpi is about 75 times faster than exact calculation. |
---|
1183 | ! This function should be expanded inline in the calling routine. |
---|
1184 | ! |
---|
1185 | ! Program History Log: |
---|
1186 | ! 91-05-07 Iredell made into inlinable function |
---|
1187 | ! 94-12-30 Iredell expand table |
---|
1188 | ! 1999-03-01 Iredell f90 module |
---|
1189 | ! 2001-02-26 Iredell ice phase |
---|
1190 | ! |
---|
1191 | ! Usage: tdpi=ftdpi(pv) |
---|
1192 | ! |
---|
1193 | ! Input argument list: |
---|
1194 | ! pv Real(krealfp) vapor pressure in Pascals |
---|
1195 | ! |
---|
1196 | ! Output argument list: |
---|
1197 | ! ftdpi Real(krealfp) dewpoint temperature in Kelvin |
---|
1198 | ! |
---|
1199 | ! Attributes: |
---|
1200 | ! Language: Fortran 90. |
---|
1201 | ! |
---|
1202 | !$$$ |
---|
1203 | implicit none |
---|
1204 | real(krealfp) ftdpi |
---|
1205 | real(krealfp),intent(in):: pv |
---|
1206 | integer jx |
---|
1207 | real(krealfp) xj |
---|
1208 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1209 | xj=min(max(c1xtdpi+c2xtdpi*pv,1._krealfp),real(nxtdpi,krealfp)) |
---|
1210 | jx=min(xj,nxtdpi-1._krealfp) |
---|
1211 | ftdpi=tbtdpi(jx)+(xj-jx)*(tbtdpi(jx+1)-tbtdpi(jx)) |
---|
1212 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1213 | end function |
---|
1214 | !------------------------------------------------------------------------------- |
---|
1215 | ! elemental function ftdpiq(pv) |
---|
1216 | function ftdpiq(pv) |
---|
1217 | !$$$ Subprogram Documentation Block |
---|
1218 | ! |
---|
1219 | ! Subprogram: ftdpiq Compute dewpoint temperature over ice |
---|
1220 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
1221 | ! |
---|
1222 | ! Abstract: Compute dewpoint temperature from vapor pressure. |
---|
1223 | ! A quadratic interpolation is done between values in a lookup table |
---|
1224 | ! computed in gtdpi. see documentation for ftdpixg for details. |
---|
1225 | ! Input values outside table range are reset to table extrema. |
---|
1226 | ! the interpolation accuracy is better than 0.00001 Kelvin |
---|
1227 | ! for dewpoint temperatures greater than 250 Kelvin, |
---|
1228 | ! but decreases to 0.002 Kelvin for a dewpoint around 230 Kelvin. |
---|
1229 | ! On the Cray, ftdpiq is about 60 times faster than exact calculation. |
---|
1230 | ! This function should be expanded inline in the calling routine. |
---|
1231 | ! |
---|
1232 | ! Program History Log: |
---|
1233 | ! 91-05-07 Iredell made into inlinable function |
---|
1234 | ! 94-12-30 Iredell quadratic interpolation |
---|
1235 | ! 1999-03-01 Iredell f90 module |
---|
1236 | ! 2001-02-26 Iredell ice phase |
---|
1237 | ! |
---|
1238 | ! Usage: tdpi=ftdpiq(pv) |
---|
1239 | ! |
---|
1240 | ! Input argument list: |
---|
1241 | ! pv Real(krealfp) vapor pressure in Pascals |
---|
1242 | ! |
---|
1243 | ! Output argument list: |
---|
1244 | ! ftdpiq Real(krealfp) dewpoint temperature in Kelvin |
---|
1245 | ! |
---|
1246 | ! Attributes: |
---|
1247 | ! Language: Fortran 90. |
---|
1248 | ! |
---|
1249 | !$$$ |
---|
1250 | implicit none |
---|
1251 | real(krealfp) ftdpiq |
---|
1252 | real(krealfp),intent(in):: pv |
---|
1253 | integer jx |
---|
1254 | real(krealfp) xj,dxj,fj1,fj2,fj3 |
---|
1255 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1256 | xj=min(max(c1xtdpi+c2xtdpi*pv,1._krealfp),real(nxtdpi,krealfp)) |
---|
1257 | jx=min(max(nint(xj),2),nxtdpi-1) |
---|
1258 | dxj=xj-jx |
---|
1259 | fj1=tbtdpi(jx-1) |
---|
1260 | fj2=tbtdpi(jx) |
---|
1261 | fj3=tbtdpi(jx+1) |
---|
1262 | ftdpiq=(((fj3+fj1)/2-fj2)*dxj+(fj3-fj1)/2)*dxj+fj2 |
---|
1263 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1264 | end function |
---|
1265 | !------------------------------------------------------------------------------- |
---|
1266 | ! elemental function ftdpix(pv) |
---|
1267 | function ftdpix(pv) |
---|
1268 | !$$$ Subprogram Documentation Block |
---|
1269 | ! |
---|
1270 | ! Subprogram: ftdpix Compute dewpoint temperature over ice |
---|
1271 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
1272 | ! |
---|
1273 | ! Abstract: exactly compute dewpoint temperature from vapor pressure. |
---|
1274 | ! An approximate dewpoint temperature for function ftdpixg |
---|
1275 | ! is obtained using ftdpi so gtdpi must be already called. |
---|
1276 | ! See documentation for ftdpixg for details. |
---|
1277 | ! |
---|
1278 | ! Program History Log: |
---|
1279 | ! 91-05-07 Iredell made into inlinable function |
---|
1280 | ! 94-12-30 Iredell exact computation |
---|
1281 | ! 1999-03-01 Iredell f90 module |
---|
1282 | ! 2001-02-26 Iredell ice phase |
---|
1283 | ! |
---|
1284 | ! Usage: tdpi=ftdpix(pv) |
---|
1285 | ! |
---|
1286 | ! Input argument list: |
---|
1287 | ! pv Real(krealfp) vapor pressure in Pascals |
---|
1288 | ! |
---|
1289 | ! Output argument list: |
---|
1290 | ! ftdpix Real(krealfp) dewpoint temperature in Kelvin |
---|
1291 | ! |
---|
1292 | ! Subprograms called: |
---|
1293 | ! (ftdpi) inlinable function to compute dewpoint temperature over ice |
---|
1294 | ! (ftdpixg) inlinable function to compute dewpoint temperature over ice |
---|
1295 | ! |
---|
1296 | ! Attributes: |
---|
1297 | ! Language: Fortran 90. |
---|
1298 | ! |
---|
1299 | !$$$ |
---|
1300 | implicit none |
---|
1301 | real(krealfp) ftdpix |
---|
1302 | real(krealfp),intent(in):: pv |
---|
1303 | real(krealfp) tg |
---|
1304 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1305 | tg=ftdpi(pv) |
---|
1306 | ftdpix=ftdpixg(tg,pv) |
---|
1307 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1308 | end function |
---|
1309 | !------------------------------------------------------------------------------- |
---|
1310 | ! elemental function ftdpixg(tg,pv) |
---|
1311 | function ftdpixg(tg,pv) |
---|
1312 | !$$$ Subprogram Documentation Block |
---|
1313 | ! |
---|
1314 | ! Subprogram: ftdpixg Compute dewpoint temperature over ice |
---|
1315 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
1316 | ! |
---|
1317 | ! Abstract: Exactly compute dewpoint temperature from vapor pressure. |
---|
1318 | ! A guess dewpoint temperature must be provided. |
---|
1319 | ! The water model assumes a perfect gas, constant specific heats |
---|
1320 | ! for gas and ice, and neglects the volume of the ice. |
---|
1321 | ! The model does account for the variation of the latent heat |
---|
1322 | ! of sublimation with temperature. The liquid option is not included. |
---|
1323 | ! The Clausius-Clapeyron equation is integrated from the triple point |
---|
1324 | ! to get the formula |
---|
1325 | ! pvs=con_psat*(tr**xa)*exp(xb*(1.-tr)) |
---|
1326 | ! where tr is ttp/t and other values are physical constants. |
---|
1327 | ! The formula is inverted by iterating Newtonian approximations |
---|
1328 | ! for each pvs until t is found to within 1.e-6 Kelvin. |
---|
1329 | ! This function can be expanded inline in the calling routine. |
---|
1330 | ! |
---|
1331 | ! Program History Log: |
---|
1332 | ! 91-05-07 Iredell made into inlinable function |
---|
1333 | ! 94-12-30 Iredell exact computation |
---|
1334 | ! 1999-03-01 Iredell f90 module |
---|
1335 | ! 2001-02-26 Iredell ice phase |
---|
1336 | ! |
---|
1337 | ! Usage: tdpi=ftdpixg(tg,pv) |
---|
1338 | ! |
---|
1339 | ! Input argument list: |
---|
1340 | ! tg Real(krealfp) guess dewpoint temperature in Kelvin |
---|
1341 | ! pv Real(krealfp) vapor pressure in Pascals |
---|
1342 | ! |
---|
1343 | ! Output argument list: |
---|
1344 | ! ftdpixg Real(krealfp) dewpoint temperature in Kelvin |
---|
1345 | ! |
---|
1346 | ! Attributes: |
---|
1347 | ! Language: Fortran 90. |
---|
1348 | ! |
---|
1349 | !$$$ |
---|
1350 | implicit none |
---|
1351 | real(krealfp) ftdpixg |
---|
1352 | real(krealfp),intent(in):: tg,pv |
---|
1353 | real(krealfp),parameter:: terrm=1.e-6 |
---|
1354 | real(krealfp),parameter:: dldt=con_cvap-con_csol |
---|
1355 | real(krealfp),parameter:: heat=con_hvap+con_hfus |
---|
1356 | real(krealfp),parameter:: xpona=-dldt/con_rv |
---|
1357 | real(krealfp),parameter:: xponb=-dldt/con_rv+heat/(con_rv*con_ttp) |
---|
1358 | real(krealfp) t,tr,pvt,el,dpvt,terr |
---|
1359 | integer i |
---|
1360 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1361 | t=tg |
---|
1362 | do i=1,100 |
---|
1363 | tr=con_ttp/t |
---|
1364 | pvt=con_psat*(tr**xpona)*exp(xponb*(1.-tr)) |
---|
1365 | el=heat+dldt*(t-con_ttp) |
---|
1366 | dpvt=el*pvt/(con_rv*t**2) |
---|
1367 | terr=(pvt-pv)/dpvt |
---|
1368 | t=t-terr |
---|
1369 | if(abs(terr).le.terrm) exit |
---|
1370 | enddo |
---|
1371 | ftdpixg=t |
---|
1372 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1373 | end function |
---|
1374 | !------------------------------------------------------------------------------- |
---|
1375 | subroutine gtdp |
---|
1376 | !$$$ Subprogram Documentation Block |
---|
1377 | ! |
---|
1378 | ! Subprogram: gtdp Compute dewpoint temperature table |
---|
1379 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
1380 | ! |
---|
1381 | ! Abstract: Compute dewpoint temperature table as a function of |
---|
1382 | ! vapor pressure for inlinable function ftdp. |
---|
1383 | ! Exact dewpoint temperatures are calculated in subprogram ftdpxg. |
---|
1384 | ! The current implementation computes a table with a length |
---|
1385 | ! of 5001 for vapor pressures ranging from 0.5 to 1000.5 Pascals |
---|
1386 | ! giving a dewpoint temperature range of 208 to 319 Kelvin. |
---|
1387 | ! |
---|
1388 | ! Program History Log: |
---|
1389 | ! 91-05-07 Iredell |
---|
1390 | ! 94-12-30 Iredell expand table |
---|
1391 | ! 1999-03-01 Iredell f90 module |
---|
1392 | ! 2001-02-26 Iredell ice phase |
---|
1393 | ! |
---|
1394 | ! Usage: call gtdp |
---|
1395 | ! |
---|
1396 | ! Subprograms called: |
---|
1397 | ! (ftdpxg) inlinable function to compute dewpoint temperature |
---|
1398 | ! |
---|
1399 | ! Attributes: |
---|
1400 | ! Language: Fortran 90. |
---|
1401 | ! |
---|
1402 | !$$$ |
---|
1403 | implicit none |
---|
1404 | integer jx |
---|
1405 | real(krealfp) xmin,xmax,xinc,t,x,pv |
---|
1406 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1407 | xmin=0.5 |
---|
1408 | xmax=10000.5 |
---|
1409 | xinc=(xmax-xmin)/(nxtdp-1) |
---|
1410 | c1xtdp=1.-xmin/xinc |
---|
1411 | c2xtdp=1./xinc |
---|
1412 | t=208.0 |
---|
1413 | do jx=1,nxtdp |
---|
1414 | x=xmin+(jx-1)*xinc |
---|
1415 | pv=x |
---|
1416 | t=ftdpxg(t,pv) |
---|
1417 | tbtdp(jx)=t |
---|
1418 | enddo |
---|
1419 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1420 | end subroutine |
---|
1421 | !------------------------------------------------------------------------------- |
---|
1422 | ! elemental function ftdp(pv) |
---|
1423 | function ftdp(pv) |
---|
1424 | !$$$ Subprogram Documentation Block |
---|
1425 | ! |
---|
1426 | ! Subprogram: ftdp Compute dewpoint temperature |
---|
1427 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
1428 | ! |
---|
1429 | ! Abstract: Compute dewpoint temperature from vapor pressure. |
---|
1430 | ! A linear interpolation is done between values in a lookup table |
---|
1431 | ! computed in gtdp. See documentation for ftdpxg for details. |
---|
1432 | ! Input values outside table range are reset to table extrema. |
---|
1433 | ! The interpolation accuracy is better than 0.0005 Kelvin |
---|
1434 | ! for dewpoint temperatures greater than 250 Kelvin, |
---|
1435 | ! but decreases to 0.02 Kelvin for a dewpoint around 230 Kelvin. |
---|
1436 | ! On the Cray, ftdp is about 75 times faster than exact calculation. |
---|
1437 | ! This function should be expanded inline in the calling routine. |
---|
1438 | ! |
---|
1439 | ! Program History Log: |
---|
1440 | ! 91-05-07 Iredell made into inlinable function |
---|
1441 | ! 94-12-30 Iredell expand table |
---|
1442 | ! 1999-03-01 Iredell f90 module |
---|
1443 | ! 2001-02-26 Iredell ice phase |
---|
1444 | ! |
---|
1445 | ! Usage: tdp=ftdp(pv) |
---|
1446 | ! |
---|
1447 | ! Input argument list: |
---|
1448 | ! pv Real(krealfp) vapor pressure in Pascals |
---|
1449 | ! |
---|
1450 | ! Output argument list: |
---|
1451 | ! ftdp Real(krealfp) dewpoint temperature in Kelvin |
---|
1452 | ! |
---|
1453 | ! Attributes: |
---|
1454 | ! Language: Fortran 90. |
---|
1455 | ! |
---|
1456 | !$$$ |
---|
1457 | implicit none |
---|
1458 | real(krealfp) ftdp |
---|
1459 | real(krealfp),intent(in):: pv |
---|
1460 | integer jx |
---|
1461 | real(krealfp) xj |
---|
1462 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1463 | xj=min(max(c1xtdp+c2xtdp*pv,1._krealfp),real(nxtdp,krealfp)) |
---|
1464 | jx=min(xj,nxtdp-1._krealfp) |
---|
1465 | ftdp=tbtdp(jx)+(xj-jx)*(tbtdp(jx+1)-tbtdp(jx)) |
---|
1466 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1467 | end function |
---|
1468 | !------------------------------------------------------------------------------- |
---|
1469 | ! elemental function ftdpq(pv) |
---|
1470 | function ftdpq(pv) |
---|
1471 | !$$$ Subprogram Documentation Block |
---|
1472 | ! |
---|
1473 | ! Subprogram: ftdpq Compute dewpoint temperature |
---|
1474 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
1475 | ! |
---|
1476 | ! Abstract: Compute dewpoint temperature from vapor pressure. |
---|
1477 | ! A quadratic interpolation is done between values in a lookup table |
---|
1478 | ! computed in gtdp. see documentation for ftdpxg for details. |
---|
1479 | ! Input values outside table range are reset to table extrema. |
---|
1480 | ! the interpolation accuracy is better than 0.00001 Kelvin |
---|
1481 | ! for dewpoint temperatures greater than 250 Kelvin, |
---|
1482 | ! but decreases to 0.002 Kelvin for a dewpoint around 230 Kelvin. |
---|
1483 | ! On the Cray, ftdpq is about 60 times faster than exact calculation. |
---|
1484 | ! This function should be expanded inline in the calling routine. |
---|
1485 | ! |
---|
1486 | ! Program History Log: |
---|
1487 | ! 91-05-07 Iredell made into inlinable function |
---|
1488 | ! 94-12-30 Iredell quadratic interpolation |
---|
1489 | ! 1999-03-01 Iredell f90 module |
---|
1490 | ! 2001-02-26 Iredell ice phase |
---|
1491 | ! |
---|
1492 | ! Usage: tdp=ftdpq(pv) |
---|
1493 | ! |
---|
1494 | ! Input argument list: |
---|
1495 | ! pv Real(krealfp) vapor pressure in Pascals |
---|
1496 | ! |
---|
1497 | ! Output argument list: |
---|
1498 | ! ftdpq Real(krealfp) dewpoint temperature in Kelvin |
---|
1499 | ! |
---|
1500 | ! Attributes: |
---|
1501 | ! Language: Fortran 90. |
---|
1502 | ! |
---|
1503 | !$$$ |
---|
1504 | implicit none |
---|
1505 | real(krealfp) ftdpq |
---|
1506 | real(krealfp),intent(in):: pv |
---|
1507 | integer jx |
---|
1508 | real(krealfp) xj,dxj,fj1,fj2,fj3 |
---|
1509 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1510 | xj=min(max(c1xtdp+c2xtdp*pv,1._krealfp),real(nxtdp,krealfp)) |
---|
1511 | jx=min(max(nint(xj),2),nxtdp-1) |
---|
1512 | dxj=xj-jx |
---|
1513 | fj1=tbtdp(jx-1) |
---|
1514 | fj2=tbtdp(jx) |
---|
1515 | fj3=tbtdp(jx+1) |
---|
1516 | ftdpq=(((fj3+fj1)/2-fj2)*dxj+(fj3-fj1)/2)*dxj+fj2 |
---|
1517 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1518 | end function |
---|
1519 | !------------------------------------------------------------------------------- |
---|
1520 | ! elemental function ftdpx(pv) |
---|
1521 | function ftdpx(pv) |
---|
1522 | !$$$ Subprogram Documentation Block |
---|
1523 | ! |
---|
1524 | ! Subprogram: ftdpx Compute dewpoint temperature |
---|
1525 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
1526 | ! |
---|
1527 | ! Abstract: exactly compute dewpoint temperature from vapor pressure. |
---|
1528 | ! An approximate dewpoint temperature for function ftdpxg |
---|
1529 | ! is obtained using ftdp so gtdp must be already called. |
---|
1530 | ! See documentation for ftdpxg for details. |
---|
1531 | ! |
---|
1532 | ! Program History Log: |
---|
1533 | ! 91-05-07 Iredell made into inlinable function |
---|
1534 | ! 94-12-30 Iredell exact computation |
---|
1535 | ! 1999-03-01 Iredell f90 module |
---|
1536 | ! 2001-02-26 Iredell ice phase |
---|
1537 | ! |
---|
1538 | ! Usage: tdp=ftdpx(pv) |
---|
1539 | ! |
---|
1540 | ! Input argument list: |
---|
1541 | ! pv Real(krealfp) vapor pressure in Pascals |
---|
1542 | ! |
---|
1543 | ! Output argument list: |
---|
1544 | ! ftdpx Real(krealfp) dewpoint temperature in Kelvin |
---|
1545 | ! |
---|
1546 | ! Subprograms called: |
---|
1547 | ! (ftdp) inlinable function to compute dewpoint temperature |
---|
1548 | ! (ftdpxg) inlinable function to compute dewpoint temperature |
---|
1549 | ! |
---|
1550 | ! Attributes: |
---|
1551 | ! Language: Fortran 90. |
---|
1552 | ! |
---|
1553 | !$$$ |
---|
1554 | implicit none |
---|
1555 | real(krealfp) ftdpx |
---|
1556 | real(krealfp),intent(in):: pv |
---|
1557 | real(krealfp) tg |
---|
1558 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1559 | tg=ftdp(pv) |
---|
1560 | ftdpx=ftdpxg(tg,pv) |
---|
1561 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1562 | end function |
---|
1563 | !------------------------------------------------------------------------------- |
---|
1564 | ! elemental function ftdpxg(tg,pv) |
---|
1565 | function ftdpxg(tg,pv) |
---|
1566 | !$$$ Subprogram Documentation Block |
---|
1567 | ! |
---|
1568 | ! Subprogram: ftdpxg Compute dewpoint temperature |
---|
1569 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
1570 | ! |
---|
1571 | ! Abstract: Exactly compute dewpoint temperature from vapor pressure. |
---|
1572 | ! A guess dewpoint temperature must be provided. |
---|
1573 | ! The saturation vapor pressure over either liquid and ice is computed |
---|
1574 | ! over liquid for temperatures above the triple point, |
---|
1575 | ! over ice for temperatures 20 degress below the triple point, |
---|
1576 | ! and a linear combination of the two for temperatures in between. |
---|
1577 | ! The water model assumes a perfect gas, constant specific heats |
---|
1578 | ! for gas, liquid and ice, and neglects the volume of the condensate. |
---|
1579 | ! The model does account for the variation of the latent heat |
---|
1580 | ! of condensation and sublimation with temperature. |
---|
1581 | ! The Clausius-Clapeyron equation is integrated from the triple point |
---|
1582 | ! to get the formula |
---|
1583 | ! pvsl=con_psat*(tr**xa)*exp(xb*(1.-tr)) |
---|
1584 | ! where tr is ttp/t and other values are physical constants. |
---|
1585 | ! The reference for this decision is Emanuel(1994), pages 116-117. |
---|
1586 | ! The formula is inverted by iterating Newtonian approximations |
---|
1587 | ! for each pvs until t is found to within 1.e-6 Kelvin. |
---|
1588 | ! This function can be expanded inline in the calling routine. |
---|
1589 | ! |
---|
1590 | ! Program History Log: |
---|
1591 | ! 91-05-07 Iredell made into inlinable function |
---|
1592 | ! 94-12-30 Iredell exact computation |
---|
1593 | ! 1999-03-01 Iredell f90 module |
---|
1594 | ! 2001-02-26 Iredell ice phase |
---|
1595 | ! |
---|
1596 | ! Usage: tdp=ftdpxg(tg,pv) |
---|
1597 | ! |
---|
1598 | ! Input argument list: |
---|
1599 | ! tg Real(krealfp) guess dewpoint temperature in Kelvin |
---|
1600 | ! pv Real(krealfp) vapor pressure in Pascals |
---|
1601 | ! |
---|
1602 | ! Output argument list: |
---|
1603 | ! ftdpxg Real(krealfp) dewpoint temperature in Kelvin |
---|
1604 | ! |
---|
1605 | ! Attributes: |
---|
1606 | ! Language: Fortran 90. |
---|
1607 | ! |
---|
1608 | !$$$ |
---|
1609 | implicit none |
---|
1610 | real(krealfp) ftdpxg |
---|
1611 | real(krealfp),intent(in):: tg,pv |
---|
1612 | real(krealfp),parameter:: terrm=1.e-6 |
---|
1613 | real(krealfp),parameter:: tliq=con_ttp |
---|
1614 | real(krealfp),parameter:: tice=con_ttp-20.0 |
---|
1615 | real(krealfp),parameter:: dldtl=con_cvap-con_cliq |
---|
1616 | real(krealfp),parameter:: heatl=con_hvap |
---|
1617 | real(krealfp),parameter:: xponal=-dldtl/con_rv |
---|
1618 | real(krealfp),parameter:: xponbl=-dldtl/con_rv+heatl/(con_rv*con_ttp) |
---|
1619 | real(krealfp),parameter:: dldti=con_cvap-con_csol |
---|
1620 | real(krealfp),parameter:: heati=con_hvap+con_hfus |
---|
1621 | real(krealfp),parameter:: xponai=-dldti/con_rv |
---|
1622 | real(krealfp),parameter:: xponbi=-dldti/con_rv+heati/(con_rv*con_ttp) |
---|
1623 | real(krealfp) t,tr,w,pvtl,pvti,pvt,ell,eli,el,dpvt,terr |
---|
1624 | integer i |
---|
1625 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1626 | t=tg |
---|
1627 | do i=1,100 |
---|
1628 | tr=con_ttp/t |
---|
1629 | if(t.ge.tliq) then |
---|
1630 | pvt=con_psat*(tr**xponal)*exp(xponbl*(1.-tr)) |
---|
1631 | el=heatl+dldtl*(t-con_ttp) |
---|
1632 | dpvt=el*pvt/(con_rv*t**2) |
---|
1633 | elseif(t.lt.tice) then |
---|
1634 | pvt=con_psat*(tr**xponai)*exp(xponbi*(1.-tr)) |
---|
1635 | el=heati+dldti*(t-con_ttp) |
---|
1636 | dpvt=el*pvt/(con_rv*t**2) |
---|
1637 | else |
---|
1638 | w=(t-tice)/(tliq-tice) |
---|
1639 | pvtl=con_psat*(tr**xponal)*exp(xponbl*(1.-tr)) |
---|
1640 | pvti=con_psat*(tr**xponai)*exp(xponbi*(1.-tr)) |
---|
1641 | pvt=w*pvtl+(1.-w)*pvti |
---|
1642 | ell=heatl+dldtl*(t-con_ttp) |
---|
1643 | eli=heati+dldti*(t-con_ttp) |
---|
1644 | dpvt=(w*ell*pvtl+(1.-w)*eli*pvti)/(con_rv*t**2) |
---|
1645 | endif |
---|
1646 | terr=(pvt-pv)/dpvt |
---|
1647 | t=t-terr |
---|
1648 | if(abs(terr).le.terrm) exit |
---|
1649 | enddo |
---|
1650 | ftdpxg=t |
---|
1651 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1652 | end function |
---|
1653 | !------------------------------------------------------------------------------- |
---|
1654 | subroutine gthe |
---|
1655 | !$$$ Subprogram Documentation Block |
---|
1656 | ! |
---|
1657 | ! Subprogram: gthe Compute equivalent potential temperature table |
---|
1658 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
1659 | ! |
---|
1660 | ! Abstract: Compute equivalent potential temperature table |
---|
1661 | ! as a function of LCL temperature and pressure over 1e5 Pa |
---|
1662 | ! to the kappa power for function fthe. |
---|
1663 | ! Equivalent potential temperatures are calculated in subprogram fthex |
---|
1664 | ! the current implementation computes a table with a first dimension |
---|
1665 | ! of 241 for temperatures ranging from 183.16 to 303.16 Kelvin |
---|
1666 | ! and a second dimension of 151 for pressure over 1e5 Pa |
---|
1667 | ! to the kappa power ranging from 0.04**rocp to 1.10**rocp. |
---|
1668 | ! |
---|
1669 | ! Program History Log: |
---|
1670 | ! 91-05-07 Iredell |
---|
1671 | ! 94-12-30 Iredell expand table |
---|
1672 | ! 1999-03-01 Iredell f90 module |
---|
1673 | ! |
---|
1674 | ! Usage: call gthe |
---|
1675 | ! |
---|
1676 | ! Subprograms called: |
---|
1677 | ! (fthex) inlinable function to compute equiv. pot. temperature |
---|
1678 | ! |
---|
1679 | ! Attributes: |
---|
1680 | ! Language: Fortran 90. |
---|
1681 | ! |
---|
1682 | !$$$ |
---|
1683 | implicit none |
---|
1684 | integer jx,jy |
---|
1685 | real(krealfp) xmin,xmax,ymin,ymax,xinc,yinc,x,y,pk,t |
---|
1686 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1687 | xmin=con_ttp-90._krealfp |
---|
1688 | xmax=con_ttp+30._krealfp |
---|
1689 | ymin=0.04_krealfp**con_rocp |
---|
1690 | ymax=1.10_krealfp**con_rocp |
---|
1691 | xinc=(xmax-xmin)/(nxthe-1) |
---|
1692 | c1xthe=1.-xmin/xinc |
---|
1693 | c2xthe=1./xinc |
---|
1694 | yinc=(ymax-ymin)/(nythe-1) |
---|
1695 | c1ythe=1.-ymin/yinc |
---|
1696 | c2ythe=1./yinc |
---|
1697 | do jy=1,nythe |
---|
1698 | y=ymin+(jy-1)*yinc |
---|
1699 | pk=y |
---|
1700 | do jx=1,nxthe |
---|
1701 | x=xmin+(jx-1)*xinc |
---|
1702 | t=x |
---|
1703 | tbthe(jx,jy)=fthex(t,pk) |
---|
1704 | enddo |
---|
1705 | enddo |
---|
1706 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1707 | end subroutine |
---|
1708 | !------------------------------------------------------------------------------- |
---|
1709 | ! elemental function fthe(t,pk) |
---|
1710 | function fthe(t,pk) |
---|
1711 | !$$$ Subprogram Documentation Block |
---|
1712 | ! |
---|
1713 | ! Subprogram: fthe Compute equivalent potential temperature |
---|
1714 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
1715 | ! |
---|
1716 | ! Abstract: Compute equivalent potential temperature at the LCL |
---|
1717 | ! from temperature and pressure over 1e5 Pa to the kappa power. |
---|
1718 | ! A bilinear interpolation is done between values in a lookup table |
---|
1719 | ! computed in gthe. see documentation for fthex for details. |
---|
1720 | ! Input values outside table range are reset to table extrema, |
---|
1721 | ! except zero is returned for too cold or high LCLs. |
---|
1722 | ! The interpolation accuracy is better than 0.01 Kelvin. |
---|
1723 | ! On the Cray, fthe is almost 6 times faster than exact calculation. |
---|
1724 | ! This function should be expanded inline in the calling routine. |
---|
1725 | ! |
---|
1726 | ! Program History Log: |
---|
1727 | ! 91-05-07 Iredell made into inlinable function |
---|
1728 | ! 94-12-30 Iredell expand table |
---|
1729 | ! 1999-03-01 Iredell f90 module |
---|
1730 | ! |
---|
1731 | ! Usage: the=fthe(t,pk) |
---|
1732 | ! |
---|
1733 | ! Input argument list: |
---|
1734 | ! t Real(krealfp) LCL temperature in Kelvin |
---|
1735 | ! pk Real(krealfp) LCL pressure over 1e5 Pa to the kappa power |
---|
1736 | ! |
---|
1737 | ! Output argument list: |
---|
1738 | ! fthe Real(krealfp) equivalent potential temperature in Kelvin |
---|
1739 | ! |
---|
1740 | ! Attributes: |
---|
1741 | ! Language: Fortran 90. |
---|
1742 | ! |
---|
1743 | !$$$ |
---|
1744 | implicit none |
---|
1745 | real(krealfp) fthe |
---|
1746 | real(krealfp),intent(in):: t,pk |
---|
1747 | integer jx,jy |
---|
1748 | real(krealfp) xj,yj,ftx1,ftx2 |
---|
1749 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1750 | xj=min(c1xthe+c2xthe*t,real(nxthe,krealfp)) |
---|
1751 | yj=min(c1ythe+c2ythe*pk,real(nythe,krealfp)) |
---|
1752 | if(xj.ge.1..and.yj.ge.1.) then |
---|
1753 | jx=min(xj,nxthe-1._krealfp) |
---|
1754 | jy=min(yj,nythe-1._krealfp) |
---|
1755 | ftx1=tbthe(jx,jy)+(xj-jx)*(tbthe(jx+1,jy)-tbthe(jx,jy)) |
---|
1756 | ftx2=tbthe(jx,jy+1)+(xj-jx)*(tbthe(jx+1,jy+1)-tbthe(jx,jy+1)) |
---|
1757 | fthe=ftx1+(yj-jy)*(ftx2-ftx1) |
---|
1758 | else |
---|
1759 | fthe=0. |
---|
1760 | endif |
---|
1761 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1762 | end function |
---|
1763 | !------------------------------------------------------------------------------- |
---|
1764 | ! elemental function ftheq(t,pk) |
---|
1765 | function ftheq(t,pk) |
---|
1766 | !$$$ Subprogram Documentation Block |
---|
1767 | ! |
---|
1768 | ! Subprogram: ftheq Compute equivalent potential temperature |
---|
1769 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
1770 | ! |
---|
1771 | ! Abstract: Compute equivalent potential temperature at the LCL |
---|
1772 | ! from temperature and pressure over 1e5 Pa to the kappa power. |
---|
1773 | ! A biquadratic interpolation is done between values in a lookup table |
---|
1774 | ! computed in gthe. see documentation for fthex for details. |
---|
1775 | ! Input values outside table range are reset to table extrema, |
---|
1776 | ! except zero is returned for too cold or high LCLs. |
---|
1777 | ! The interpolation accuracy is better than 0.0002 Kelvin. |
---|
1778 | ! On the Cray, ftheq is almost 3 times faster than exact calculation. |
---|
1779 | ! This function should be expanded inline in the calling routine. |
---|
1780 | ! |
---|
1781 | ! Program History Log: |
---|
1782 | ! 91-05-07 Iredell made into inlinable function |
---|
1783 | ! 94-12-30 Iredell quadratic interpolation |
---|
1784 | ! 1999-03-01 Iredell f90 module |
---|
1785 | ! |
---|
1786 | ! Usage: the=ftheq(t,pk) |
---|
1787 | ! |
---|
1788 | ! Input argument list: |
---|
1789 | ! t Real(krealfp) LCL temperature in Kelvin |
---|
1790 | ! pk Real(krealfp) LCL pressure over 1e5 Pa to the kappa power |
---|
1791 | ! |
---|
1792 | ! Output argument list: |
---|
1793 | ! ftheq Real(krealfp) equivalent potential temperature in Kelvin |
---|
1794 | ! |
---|
1795 | ! Attributes: |
---|
1796 | ! Language: Fortran 90. |
---|
1797 | ! |
---|
1798 | !$$$ |
---|
1799 | implicit none |
---|
1800 | real(krealfp) ftheq |
---|
1801 | real(krealfp),intent(in):: t,pk |
---|
1802 | integer jx,jy |
---|
1803 | real(krealfp) xj,yj,dxj,dyj |
---|
1804 | real(krealfp) ft11,ft12,ft13,ft21,ft22,ft23,ft31,ft32,ft33 |
---|
1805 | real(krealfp) ftx1,ftx2,ftx3 |
---|
1806 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1807 | xj=min(c1xthe+c2xthe*t,real(nxthe,krealfp)) |
---|
1808 | yj=min(c1ythe+c2ythe*pk,real(nythe,krealfp)) |
---|
1809 | if(xj.ge.1..and.yj.ge.1.) then |
---|
1810 | jx=min(max(nint(xj),2),nxthe-1) |
---|
1811 | jy=min(max(nint(yj),2),nythe-1) |
---|
1812 | dxj=xj-jx |
---|
1813 | dyj=yj-jy |
---|
1814 | ft11=tbthe(jx-1,jy-1) |
---|
1815 | ft12=tbthe(jx-1,jy) |
---|
1816 | ft13=tbthe(jx-1,jy+1) |
---|
1817 | ft21=tbthe(jx,jy-1) |
---|
1818 | ft22=tbthe(jx,jy) |
---|
1819 | ft23=tbthe(jx,jy+1) |
---|
1820 | ft31=tbthe(jx+1,jy-1) |
---|
1821 | ft32=tbthe(jx+1,jy) |
---|
1822 | ft33=tbthe(jx+1,jy+1) |
---|
1823 | ftx1=(((ft31+ft11)/2-ft21)*dxj+(ft31-ft11)/2)*dxj+ft21 |
---|
1824 | ftx2=(((ft32+ft12)/2-ft22)*dxj+(ft32-ft12)/2)*dxj+ft22 |
---|
1825 | ftx3=(((ft33+ft13)/2-ft23)*dxj+(ft33-ft13)/2)*dxj+ft23 |
---|
1826 | ftheq=(((ftx3+ftx1)/2-ftx2)*dyj+(ftx3-ftx1)/2)*dyj+ftx2 |
---|
1827 | else |
---|
1828 | ftheq=0. |
---|
1829 | endif |
---|
1830 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1831 | end function |
---|
1832 | !------------------------------------------------------------------------------- |
---|
1833 | ! elemental function fthex(t,pk) |
---|
1834 | function fthex(t,pk) |
---|
1835 | !$$$ Subprogram Documentation Block |
---|
1836 | ! |
---|
1837 | ! Subprogram: fthex Compute equivalent potential temperature |
---|
1838 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
1839 | ! |
---|
1840 | ! Abstract: Exactly compute equivalent potential temperature at the LCL |
---|
1841 | ! from temperature and pressure over 1e5 Pa to the kappa power. |
---|
1842 | ! Equivalent potential temperature is constant for a saturated parcel |
---|
1843 | ! rising adiabatically up a moist adiabat when the heat and mass |
---|
1844 | ! of the condensed water are neglected. Ice is also neglected. |
---|
1845 | ! The formula for equivalent potential temperature (Holton) is |
---|
1846 | ! the=t*(pd**(-rocp))*exp(el*eps*pv/(cp*t*pd)) |
---|
1847 | ! where t is the temperature, pv is the saturated vapor pressure, |
---|
1848 | ! pd is the dry pressure p-pv, el is the temperature dependent |
---|
1849 | ! latent heat of condensation hvap+dldt*(t-ttp), and other values |
---|
1850 | ! are physical constants defined in parameter statements in the code. |
---|
1851 | ! Zero is returned if the input values make saturation impossible. |
---|
1852 | ! This function should be expanded inline in the calling routine. |
---|
1853 | ! |
---|
1854 | ! Program History Log: |
---|
1855 | ! 91-05-07 Iredell made into inlinable function |
---|
1856 | ! 94-12-30 Iredell exact computation |
---|
1857 | ! 1999-03-01 Iredell f90 module |
---|
1858 | ! |
---|
1859 | ! Usage: the=fthex(t,pk) |
---|
1860 | ! |
---|
1861 | ! Input argument list: |
---|
1862 | ! t Real(krealfp) LCL temperature in Kelvin |
---|
1863 | ! pk Real(krealfp) LCL pressure over 1e5 Pa to the kappa power |
---|
1864 | ! |
---|
1865 | ! Output argument list: |
---|
1866 | ! fthex Real(krealfp) equivalent potential temperature in Kelvin |
---|
1867 | ! |
---|
1868 | ! Attributes: |
---|
1869 | ! Language: Fortran 90. |
---|
1870 | ! |
---|
1871 | !$$$ |
---|
1872 | implicit none |
---|
1873 | real(krealfp) fthex |
---|
1874 | real(krealfp),intent(in):: t,pk |
---|
1875 | real(krealfp) p,tr,pv,pd,el,expo,expmax |
---|
1876 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1877 | p=pk**con_cpor |
---|
1878 | tr=con_ttp/t |
---|
1879 | pv=psatb*(tr**con_xpona)*exp(con_xponb*(1.-tr)) |
---|
1880 | pd=p-pv |
---|
1881 | if(pd.gt.pv) then |
---|
1882 | el=con_hvap+con_dldt*(t-con_ttp) |
---|
1883 | expo=el*con_eps*pv/(con_cp*t*pd) |
---|
1884 | fthex=t*pd**(-con_rocp)*exp(expo) |
---|
1885 | else |
---|
1886 | fthex=0. |
---|
1887 | endif |
---|
1888 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1889 | end function |
---|
1890 | !------------------------------------------------------------------------------- |
---|
1891 | subroutine gtma |
---|
1892 | !$$$ Subprogram Documentation Block |
---|
1893 | ! |
---|
1894 | ! Subprogram: gtma Compute moist adiabat tables |
---|
1895 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
1896 | ! |
---|
1897 | ! Abstract: Compute temperature and specific humidity tables |
---|
1898 | ! as a function of equivalent potential temperature and |
---|
1899 | ! pressure over 1e5 Pa to the kappa power for subprogram stma. |
---|
1900 | ! Exact parcel temperatures are calculated in subprogram stmaxg. |
---|
1901 | ! The current implementation computes a table with a first dimension |
---|
1902 | ! of 151 for equivalent potential temperatures ranging from 200 to 500 |
---|
1903 | ! Kelvin and a second dimension of 121 for pressure over 1e5 Pa |
---|
1904 | ! to the kappa power ranging from 0.01**rocp to 1.10**rocp. |
---|
1905 | ! |
---|
1906 | ! Program History Log: |
---|
1907 | ! 91-05-07 Iredell |
---|
1908 | ! 94-12-30 Iredell expand table |
---|
1909 | ! 1999-03-01 Iredell f90 module |
---|
1910 | ! |
---|
1911 | ! Usage: call gtma |
---|
1912 | ! |
---|
1913 | ! Subprograms called: |
---|
1914 | ! (stmaxg) inlinable subprogram to compute parcel temperature |
---|
1915 | ! |
---|
1916 | ! Attributes: |
---|
1917 | ! Language: Fortran 90. |
---|
1918 | ! |
---|
1919 | !$$$ |
---|
1920 | implicit none |
---|
1921 | integer jx,jy |
---|
1922 | real(krealfp) xmin,xmax,ymin,ymax,xinc,yinc,x,y,pk,the,t,q,tg |
---|
1923 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1924 | xmin=200._krealfp |
---|
1925 | xmax=500._krealfp |
---|
1926 | ymin=0.01_krealfp**con_rocp |
---|
1927 | ymax=1.10_krealfp**con_rocp |
---|
1928 | xinc=(xmax-xmin)/(nxma-1) |
---|
1929 | c1xma=1.-xmin/xinc |
---|
1930 | c2xma=1./xinc |
---|
1931 | yinc=(ymax-ymin)/(nyma-1) |
---|
1932 | c1yma=1.-ymin/yinc |
---|
1933 | c2yma=1./yinc |
---|
1934 | do jy=1,nyma |
---|
1935 | y=ymin+(jy-1)*yinc |
---|
1936 | pk=y |
---|
1937 | tg=xmin*y |
---|
1938 | do jx=1,nxma |
---|
1939 | x=xmin+(jx-1)*xinc |
---|
1940 | the=x |
---|
1941 | call stmaxg(tg,the,pk,t,q) |
---|
1942 | tbtma(jx,jy)=t |
---|
1943 | tbqma(jx,jy)=q |
---|
1944 | tg=t |
---|
1945 | enddo |
---|
1946 | enddo |
---|
1947 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1948 | end subroutine |
---|
1949 | !------------------------------------------------------------------------------- |
---|
1950 | ! elemental subroutine stma(the,pk,tma,qma) |
---|
1951 | subroutine stma(the,pk,tma,qma) |
---|
1952 | !$$$ Subprogram Documentation Block |
---|
1953 | ! |
---|
1954 | ! Subprogram: stma Compute moist adiabat temperature |
---|
1955 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
1956 | ! |
---|
1957 | ! Abstract: Compute temperature and specific humidity of a parcel |
---|
1958 | ! lifted up a moist adiabat from equivalent potential temperature |
---|
1959 | ! at the LCL and pressure over 1e5 Pa to the kappa power. |
---|
1960 | ! Bilinear interpolations are done between values in a lookup table |
---|
1961 | ! computed in gtma. See documentation for stmaxg for details. |
---|
1962 | ! Input values outside table range are reset to table extrema. |
---|
1963 | ! The interpolation accuracy is better than 0.01 Kelvin |
---|
1964 | ! and 5.e-6 kg/kg for temperature and humidity, respectively. |
---|
1965 | ! On the Cray, stma is about 35 times faster than exact calculation. |
---|
1966 | ! This subprogram should be expanded inline in the calling routine. |
---|
1967 | ! |
---|
1968 | ! Program History Log: |
---|
1969 | ! 91-05-07 Iredell made into inlinable function |
---|
1970 | ! 94-12-30 Iredell expand table |
---|
1971 | ! 1999-03-01 Iredell f90 module |
---|
1972 | ! |
---|
1973 | ! Usage: call stma(the,pk,tma,qma) |
---|
1974 | ! |
---|
1975 | ! Input argument list: |
---|
1976 | ! the Real(krealfp) equivalent potential temperature in Kelvin |
---|
1977 | ! pk Real(krealfp) pressure over 1e5 Pa to the kappa power |
---|
1978 | ! |
---|
1979 | ! Output argument list: |
---|
1980 | ! tma Real(krealfp) parcel temperature in Kelvin |
---|
1981 | ! qma Real(krealfp) parcel specific humidity in kg/kg |
---|
1982 | ! |
---|
1983 | ! Attributes: |
---|
1984 | ! Language: Fortran 90. |
---|
1985 | ! |
---|
1986 | !$$$ |
---|
1987 | implicit none |
---|
1988 | real(krealfp),intent(in):: the,pk |
---|
1989 | real(krealfp),intent(out):: tma,qma |
---|
1990 | integer jx,jy |
---|
1991 | real(krealfp) xj,yj,ftx1,ftx2,qx1,qx2 |
---|
1992 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
1993 | xj=min(max(c1xma+c2xma*the,1._krealfp),real(nxma,krealfp)) |
---|
1994 | yj=min(max(c1yma+c2yma*pk,1._krealfp),real(nyma,krealfp)) |
---|
1995 | jx=min(xj,nxma-1._krealfp) |
---|
1996 | jy=min(yj,nyma-1._krealfp) |
---|
1997 | ftx1=tbtma(jx,jy)+(xj-jx)*(tbtma(jx+1,jy)-tbtma(jx,jy)) |
---|
1998 | ftx2=tbtma(jx,jy+1)+(xj-jx)*(tbtma(jx+1,jy+1)-tbtma(jx,jy+1)) |
---|
1999 | tma=ftx1+(yj-jy)*(ftx2-ftx1) |
---|
2000 | qx1=tbqma(jx,jy)+(xj-jx)*(tbqma(jx+1,jy)-tbqma(jx,jy)) |
---|
2001 | qx2=tbqma(jx,jy+1)+(xj-jx)*(tbqma(jx+1,jy+1)-tbqma(jx,jy+1)) |
---|
2002 | qma=qx1+(yj-jy)*(qx2-qx1) |
---|
2003 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2004 | end subroutine |
---|
2005 | !------------------------------------------------------------------------------- |
---|
2006 | ! elemental subroutine stmaq(the,pk,tma,qma) |
---|
2007 | subroutine stmaq(the,pk,tma,qma) |
---|
2008 | !$$$ Subprogram Documentation Block |
---|
2009 | ! |
---|
2010 | ! Subprogram: stmaq Compute moist adiabat temperature |
---|
2011 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
2012 | ! |
---|
2013 | ! Abstract: Compute temperature and specific humidity of a parcel |
---|
2014 | ! lifted up a moist adiabat from equivalent potential temperature |
---|
2015 | ! at the LCL and pressure over 1e5 Pa to the kappa power. |
---|
2016 | ! Biquadratic interpolations are done between values in a lookup table |
---|
2017 | ! computed in gtma. See documentation for stmaxg for details. |
---|
2018 | ! Input values outside table range are reset to table extrema. |
---|
2019 | ! the interpolation accuracy is better than 0.0005 Kelvin |
---|
2020 | ! and 1.e-7 kg/kg for temperature and humidity, respectively. |
---|
2021 | ! On the Cray, stmaq is about 25 times faster than exact calculation. |
---|
2022 | ! This subprogram should be expanded inline in the calling routine. |
---|
2023 | ! |
---|
2024 | ! Program History Log: |
---|
2025 | ! 91-05-07 Iredell made into inlinable function |
---|
2026 | ! 94-12-30 Iredell quadratic interpolation |
---|
2027 | ! 1999-03-01 Iredell f90 module |
---|
2028 | ! |
---|
2029 | ! Usage: call stmaq(the,pk,tma,qma) |
---|
2030 | ! |
---|
2031 | ! Input argument list: |
---|
2032 | ! the Real(krealfp) equivalent potential temperature in Kelvin |
---|
2033 | ! pk Real(krealfp) pressure over 1e5 Pa to the kappa power |
---|
2034 | ! |
---|
2035 | ! Output argument list: |
---|
2036 | ! tmaq Real(krealfp) parcel temperature in Kelvin |
---|
2037 | ! qma Real(krealfp) parcel specific humidity in kg/kg |
---|
2038 | ! |
---|
2039 | ! Attributes: |
---|
2040 | ! Language: Fortran 90. |
---|
2041 | ! |
---|
2042 | !$$$ |
---|
2043 | implicit none |
---|
2044 | real(krealfp),intent(in):: the,pk |
---|
2045 | real(krealfp),intent(out):: tma,qma |
---|
2046 | integer jx,jy |
---|
2047 | real(krealfp) xj,yj,dxj,dyj |
---|
2048 | real(krealfp) ft11,ft12,ft13,ft21,ft22,ft23,ft31,ft32,ft33 |
---|
2049 | real(krealfp) ftx1,ftx2,ftx3 |
---|
2050 | real(krealfp) q11,q12,q13,q21,q22,q23,q31,q32,q33,qx1,qx2,qx3 |
---|
2051 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2052 | xj=min(max(c1xma+c2xma*the,1._krealfp),real(nxma,krealfp)) |
---|
2053 | yj=min(max(c1yma+c2yma*pk,1._krealfp),real(nyma,krealfp)) |
---|
2054 | jx=min(max(nint(xj),2),nxma-1) |
---|
2055 | jy=min(max(nint(yj),2),nyma-1) |
---|
2056 | dxj=xj-jx |
---|
2057 | dyj=yj-jy |
---|
2058 | ft11=tbtma(jx-1,jy-1) |
---|
2059 | ft12=tbtma(jx-1,jy) |
---|
2060 | ft13=tbtma(jx-1,jy+1) |
---|
2061 | ft21=tbtma(jx,jy-1) |
---|
2062 | ft22=tbtma(jx,jy) |
---|
2063 | ft23=tbtma(jx,jy+1) |
---|
2064 | ft31=tbtma(jx+1,jy-1) |
---|
2065 | ft32=tbtma(jx+1,jy) |
---|
2066 | ft33=tbtma(jx+1,jy+1) |
---|
2067 | ftx1=(((ft31+ft11)/2-ft21)*dxj+(ft31-ft11)/2)*dxj+ft21 |
---|
2068 | ftx2=(((ft32+ft12)/2-ft22)*dxj+(ft32-ft12)/2)*dxj+ft22 |
---|
2069 | ftx3=(((ft33+ft13)/2-ft23)*dxj+(ft33-ft13)/2)*dxj+ft23 |
---|
2070 | tma=(((ftx3+ftx1)/2-ftx2)*dyj+(ftx3-ftx1)/2)*dyj+ftx2 |
---|
2071 | q11=tbqma(jx-1,jy-1) |
---|
2072 | q12=tbqma(jx-1,jy) |
---|
2073 | q13=tbqma(jx-1,jy+1) |
---|
2074 | q21=tbqma(jx,jy-1) |
---|
2075 | q22=tbqma(jx,jy) |
---|
2076 | q23=tbqma(jx,jy+1) |
---|
2077 | q31=tbqma(jx+1,jy-1) |
---|
2078 | q32=tbqma(jx+1,jy) |
---|
2079 | q33=tbqma(jx+1,jy+1) |
---|
2080 | qx1=(((q31+q11)/2-q21)*dxj+(q31-q11)/2)*dxj+q21 |
---|
2081 | qx2=(((q32+q12)/2-q22)*dxj+(q32-q12)/2)*dxj+q22 |
---|
2082 | qx3=(((q33+q13)/2-q23)*dxj+(q33-q13)/2)*dxj+q23 |
---|
2083 | qma=(((qx3+qx1)/2-qx2)*dyj+(qx3-qx1)/2)*dyj+qx2 |
---|
2084 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2085 | end subroutine |
---|
2086 | !------------------------------------------------------------------------------- |
---|
2087 | ! elemental subroutine stmax(the,pk,tma,qma) |
---|
2088 | subroutine stmax(the,pk,tma,qma) |
---|
2089 | !$$$ Subprogram Documentation Block |
---|
2090 | ! |
---|
2091 | ! Subprogram: stmax Compute moist adiabat temperature |
---|
2092 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
2093 | ! |
---|
2094 | ! Abstract: Exactly compute temperature and humidity of a parcel |
---|
2095 | ! lifted up a moist adiabat from equivalent potential temperature |
---|
2096 | ! at the LCL and pressure over 1e5 Pa to the kappa power. |
---|
2097 | ! An approximate parcel temperature for subprogram stmaxg |
---|
2098 | ! is obtained using stma so gtma must be already called. |
---|
2099 | ! See documentation for stmaxg for details. |
---|
2100 | ! |
---|
2101 | ! Program History Log: |
---|
2102 | ! 91-05-07 Iredell made into inlinable function |
---|
2103 | ! 94-12-30 Iredell exact computation |
---|
2104 | ! 1999-03-01 Iredell f90 module |
---|
2105 | ! |
---|
2106 | ! Usage: call stmax(the,pk,tma,qma) |
---|
2107 | ! |
---|
2108 | ! Input argument list: |
---|
2109 | ! the Real(krealfp) equivalent potential temperature in Kelvin |
---|
2110 | ! pk Real(krealfp) pressure over 1e5 Pa to the kappa power |
---|
2111 | ! |
---|
2112 | ! Output argument list: |
---|
2113 | ! tma Real(krealfp) parcel temperature in Kelvin |
---|
2114 | ! qma Real(krealfp) parcel specific humidity in kg/kg |
---|
2115 | ! |
---|
2116 | ! Subprograms called: |
---|
2117 | ! (stma) inlinable subprogram to compute parcel temperature |
---|
2118 | ! (stmaxg) inlinable subprogram to compute parcel temperature |
---|
2119 | ! |
---|
2120 | ! Attributes: |
---|
2121 | ! Language: Fortran 90. |
---|
2122 | ! |
---|
2123 | !$$$ |
---|
2124 | implicit none |
---|
2125 | real(krealfp),intent(in):: the,pk |
---|
2126 | real(krealfp),intent(out):: tma,qma |
---|
2127 | real(krealfp) tg,qg |
---|
2128 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2129 | call stma(the,pk,tg,qg) |
---|
2130 | call stmaxg(tg,the,pk,tma,qma) |
---|
2131 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2132 | end subroutine |
---|
2133 | !------------------------------------------------------------------------------- |
---|
2134 | ! elemental subroutine stmaxg(tg,the,pk,tma,qma) |
---|
2135 | subroutine stmaxg(tg,the,pk,tma,qma) |
---|
2136 | !$$$ Subprogram Documentation Block |
---|
2137 | ! |
---|
2138 | ! Subprogram: stmaxg Compute moist adiabat temperature |
---|
2139 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
2140 | ! |
---|
2141 | ! Abstract: exactly compute temperature and humidity of a parcel |
---|
2142 | ! lifted up a moist adiabat from equivalent potential temperature |
---|
2143 | ! at the LCL and pressure over 1e5 Pa to the kappa power. |
---|
2144 | ! A guess parcel temperature must be provided. |
---|
2145 | ! Equivalent potential temperature is constant for a saturated parcel |
---|
2146 | ! rising adiabatically up a moist adiabat when the heat and mass |
---|
2147 | ! of the condensed water are neglected. Ice is also neglected. |
---|
2148 | ! The formula for equivalent potential temperature (Holton) is |
---|
2149 | ! the=t*(pd**(-rocp))*exp(el*eps*pv/(cp*t*pd)) |
---|
2150 | ! where t is the temperature, pv is the saturated vapor pressure, |
---|
2151 | ! pd is the dry pressure p-pv, el is the temperature dependent |
---|
2152 | ! latent heat of condensation hvap+dldt*(t-ttp), and other values |
---|
2153 | ! are physical constants defined in parameter statements in the code. |
---|
2154 | ! The formula is inverted by iterating Newtonian approximations |
---|
2155 | ! for each the and p until t is found to within 1.e-4 Kelvin. |
---|
2156 | ! The specific humidity is then computed from pv and pd. |
---|
2157 | ! This subprogram can be expanded inline in the calling routine. |
---|
2158 | ! |
---|
2159 | ! Program History Log: |
---|
2160 | ! 91-05-07 Iredell made into inlinable function |
---|
2161 | ! 94-12-30 Iredell exact computation |
---|
2162 | ! 1999-03-01 Iredell f90 module |
---|
2163 | ! |
---|
2164 | ! Usage: call stmaxg(tg,the,pk,tma,qma) |
---|
2165 | ! |
---|
2166 | ! Input argument list: |
---|
2167 | ! tg Real(krealfp) guess parcel temperature in Kelvin |
---|
2168 | ! the Real(krealfp) equivalent potential temperature in Kelvin |
---|
2169 | ! pk Real(krealfp) pressure over 1e5 Pa to the kappa power |
---|
2170 | ! |
---|
2171 | ! Output argument list: |
---|
2172 | ! tma Real(krealfp) parcel temperature in Kelvin |
---|
2173 | ! qma Real(krealfp) parcel specific humidity in kg/kg |
---|
2174 | ! |
---|
2175 | ! Attributes: |
---|
2176 | ! Language: Fortran 90. |
---|
2177 | ! |
---|
2178 | !$$$ |
---|
2179 | implicit none |
---|
2180 | real(krealfp),intent(in):: tg,the,pk |
---|
2181 | real(krealfp),intent(out):: tma,qma |
---|
2182 | real(krealfp),parameter:: terrm=1.e-4 |
---|
2183 | real(krealfp) t,p,tr,pv,pd,el,expo,thet,dthet,terr |
---|
2184 | integer i |
---|
2185 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2186 | t=tg |
---|
2187 | p=pk**con_cpor |
---|
2188 | do i=1,100 |
---|
2189 | tr=con_ttp/t |
---|
2190 | pv=psatb*(tr**con_xpona)*exp(con_xponb*(1.-tr)) |
---|
2191 | pd=p-pv |
---|
2192 | el=con_hvap+con_dldt*(t-con_ttp) |
---|
2193 | expo=el*con_eps*pv/(con_cp*t*pd) |
---|
2194 | thet=t*pd**(-con_rocp)*exp(expo) |
---|
2195 | dthet=thet/t*(1.+expo*(con_dldt*t/el+el*p/(con_rv*t*pd))) |
---|
2196 | terr=(thet-the)/dthet |
---|
2197 | t=t-terr |
---|
2198 | if(abs(terr).le.terrm) exit |
---|
2199 | enddo |
---|
2200 | tma=t |
---|
2201 | tr=con_ttp/t |
---|
2202 | pv=psatb*(tr**con_xpona)*exp(con_xponb*(1.-tr)) |
---|
2203 | pd=p-pv |
---|
2204 | qma=con_eps*pv/(pd+con_eps*pv) |
---|
2205 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2206 | end subroutine |
---|
2207 | !------------------------------------------------------------------------------- |
---|
2208 | subroutine gpkap |
---|
2209 | !$$$ Subprogram documentation block |
---|
2210 | ! |
---|
2211 | ! Subprogram: gpkap Compute coefficients for p**kappa |
---|
2212 | ! Author: Phillips org: w/NMC2X2 Date: 29 dec 82 |
---|
2213 | ! |
---|
2214 | ! Abstract: Computes pressure to the kappa table as a function of pressure |
---|
2215 | ! for the table lookup function fpkap. |
---|
2216 | ! Exact pressure to the kappa values are calculated in subprogram fpkapx. |
---|
2217 | ! The current implementation computes a table with a length |
---|
2218 | ! of 5501 for pressures ranging up to 110000 Pascals. |
---|
2219 | ! |
---|
2220 | ! Program History Log: |
---|
2221 | ! 94-12-30 Iredell |
---|
2222 | ! 1999-03-01 Iredell f90 module |
---|
2223 | ! 1999-03-24 Iredell table lookup |
---|
2224 | ! |
---|
2225 | ! Usage: call gpkap |
---|
2226 | ! |
---|
2227 | ! Subprograms called: |
---|
2228 | ! fpkapx function to compute exact pressure to the kappa |
---|
2229 | ! |
---|
2230 | ! Attributes: |
---|
2231 | ! Language: Fortran 90. |
---|
2232 | ! |
---|
2233 | !$$$ |
---|
2234 | implicit none |
---|
2235 | integer jx |
---|
2236 | real(krealfp) xmin,xmax,xinc,x,p |
---|
2237 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2238 | xmin=0._krealfp |
---|
2239 | xmax=110000._krealfp |
---|
2240 | xinc=(xmax-xmin)/(nxpkap-1) |
---|
2241 | c1xpkap=1.-xmin/xinc |
---|
2242 | c2xpkap=1./xinc |
---|
2243 | do jx=1,nxpkap |
---|
2244 | x=xmin+(jx-1)*xinc |
---|
2245 | p=x |
---|
2246 | tbpkap(jx)=fpkapx(p) |
---|
2247 | enddo |
---|
2248 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2249 | end subroutine |
---|
2250 | !------------------------------------------------------------------------------- |
---|
2251 | ! elemental function fpkap(p) |
---|
2252 | function fpkap(p) |
---|
2253 | !$$$ Subprogram Documentation Block |
---|
2254 | ! |
---|
2255 | ! Subprogram: fpkap raise pressure to the kappa power. |
---|
2256 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
2257 | ! |
---|
2258 | ! Abstract: Raise pressure over 1e5 Pa to the kappa power. |
---|
2259 | ! A linear interpolation is done between values in a lookup table |
---|
2260 | ! computed in gpkap. See documentation for fpkapx for details. |
---|
2261 | ! Input values outside table range are reset to table extrema. |
---|
2262 | ! The interpolation accuracy ranges from 9 decimal places |
---|
2263 | ! at 100000 Pascals to 5 decimal places at 1000 Pascals. |
---|
2264 | ! On the Cray, fpkap is over 5 times faster than exact calculation. |
---|
2265 | ! This function should be expanded inline in the calling routine. |
---|
2266 | ! |
---|
2267 | ! Program History Log: |
---|
2268 | ! 91-05-07 Iredell made into inlinable function |
---|
2269 | ! 94-12-30 Iredell standardized kappa, |
---|
2270 | ! increased range and accuracy |
---|
2271 | ! 1999-03-01 Iredell f90 module |
---|
2272 | ! 1999-03-24 Iredell table lookup |
---|
2273 | ! |
---|
2274 | ! Usage: pkap=fpkap(p) |
---|
2275 | ! |
---|
2276 | ! Input argument list: |
---|
2277 | ! p Real(krealfp) pressure in Pascals |
---|
2278 | ! |
---|
2279 | ! Output argument list: |
---|
2280 | ! fpkap Real(krealfp) p over 1e5 Pa to the kappa power |
---|
2281 | ! |
---|
2282 | ! Attributes: |
---|
2283 | ! Language: Fortran 90. |
---|
2284 | ! |
---|
2285 | !$$$ |
---|
2286 | implicit none |
---|
2287 | real(krealfp) fpkap |
---|
2288 | real(krealfp),intent(in):: p |
---|
2289 | integer jx |
---|
2290 | real(krealfp) xj |
---|
2291 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2292 | xj=min(max(c1xpkap+c2xpkap*p,1._krealfp),real(nxpkap,krealfp)) |
---|
2293 | jx=min(xj,nxpkap-1._krealfp) |
---|
2294 | fpkap=tbpkap(jx)+(xj-jx)*(tbpkap(jx+1)-tbpkap(jx)) |
---|
2295 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2296 | end function |
---|
2297 | !------------------------------------------------------------------------------- |
---|
2298 | ! elemental function fpkapq(p) |
---|
2299 | function fpkapq(p) |
---|
2300 | !$$$ Subprogram Documentation Block |
---|
2301 | ! |
---|
2302 | ! Subprogram: fpkapq raise pressure to the kappa power. |
---|
2303 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
2304 | ! |
---|
2305 | ! Abstract: Raise pressure over 1e5 Pa to the kappa power. |
---|
2306 | ! A quadratic interpolation is done between values in a lookup table |
---|
2307 | ! computed in gpkap. see documentation for fpkapx for details. |
---|
2308 | ! Input values outside table range are reset to table extrema. |
---|
2309 | ! The interpolation accuracy ranges from 12 decimal places |
---|
2310 | ! at 100000 Pascals to 7 decimal places at 1000 Pascals. |
---|
2311 | ! On the Cray, fpkap is over 4 times faster than exact calculation. |
---|
2312 | ! This function should be expanded inline in the calling routine. |
---|
2313 | ! |
---|
2314 | ! Program History Log: |
---|
2315 | ! 91-05-07 Iredell made into inlinable function |
---|
2316 | ! 94-12-30 Iredell standardized kappa, |
---|
2317 | ! increased range and accuracy |
---|
2318 | ! 1999-03-01 Iredell f90 module |
---|
2319 | ! 1999-03-24 Iredell table lookup |
---|
2320 | ! |
---|
2321 | ! Usage: pkap=fpkapq(p) |
---|
2322 | ! |
---|
2323 | ! Input argument list: |
---|
2324 | ! p Real(krealfp) pressure in Pascals |
---|
2325 | ! |
---|
2326 | ! Output argument list: |
---|
2327 | ! fpkapq Real(krealfp) p over 1e5 Pa to the kappa power |
---|
2328 | ! |
---|
2329 | ! Attributes: |
---|
2330 | ! Language: Fortran 90. |
---|
2331 | ! |
---|
2332 | !$$$ |
---|
2333 | implicit none |
---|
2334 | real(krealfp) fpkapq |
---|
2335 | real(krealfp),intent(in):: p |
---|
2336 | integer jx |
---|
2337 | real(krealfp) xj,dxj,fj1,fj2,fj3 |
---|
2338 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2339 | xj=min(max(c1xpkap+c2xpkap*p,1._krealfp),real(nxpkap,krealfp)) |
---|
2340 | jx=min(max(nint(xj),2),nxpkap-1) |
---|
2341 | dxj=xj-jx |
---|
2342 | fj1=tbpkap(jx-1) |
---|
2343 | fj2=tbpkap(jx) |
---|
2344 | fj3=tbpkap(jx+1) |
---|
2345 | fpkapq=(((fj3+fj1)/2-fj2)*dxj+(fj3-fj1)/2)*dxj+fj2 |
---|
2346 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2347 | end function |
---|
2348 | !------------------------------------------------------------------------------- |
---|
2349 | function fpkapo(p) |
---|
2350 | !$$$ Subprogram documentation block |
---|
2351 | ! |
---|
2352 | ! Subprogram: fpkapo raise surface pressure to the kappa power. |
---|
2353 | ! Author: Phillips org: w/NMC2X2 Date: 29 dec 82 |
---|
2354 | ! |
---|
2355 | ! Abstract: Raise surface pressure over 1e5 Pa to the kappa power |
---|
2356 | ! using a rational weighted chebyshev approximation. |
---|
2357 | ! The numerator is of order 2 and the denominator is of order 4. |
---|
2358 | ! The pressure range is 40000-110000 Pa and kappa is defined in fpkapx. |
---|
2359 | ! The accuracy of this approximation is almost 8 decimal places. |
---|
2360 | ! On the Cray, fpkap is over 10 times faster than exact calculation. |
---|
2361 | ! This function should be expanded inline in the calling routine. |
---|
2362 | ! |
---|
2363 | ! Program History Log: |
---|
2364 | ! 91-05-07 Iredell made into inlinable function |
---|
2365 | ! 94-12-30 Iredell standardized kappa, |
---|
2366 | ! increased range and accuracy |
---|
2367 | ! 1999-03-01 Iredell f90 module |
---|
2368 | ! |
---|
2369 | ! Usage: pkap=fpkapo(p) |
---|
2370 | ! |
---|
2371 | ! Input argument list: |
---|
2372 | ! p Real(krealfp) surface pressure in Pascals |
---|
2373 | ! p should be in the range 40000 to 110000 |
---|
2374 | ! |
---|
2375 | ! Output argument list: |
---|
2376 | ! fpkapo Real(krealfp) p over 1e5 Pa to the kappa power |
---|
2377 | ! |
---|
2378 | ! Attributes: |
---|
2379 | ! Language: Fortran 90. |
---|
2380 | ! |
---|
2381 | !$$$ |
---|
2382 | implicit none |
---|
2383 | real(krealfp) fpkapo |
---|
2384 | real(krealfp),intent(in):: p |
---|
2385 | integer,parameter:: nnpk=2,ndpk=4 |
---|
2386 | real(krealfp):: cnpk(0:nnpk)=(/3.13198449e-1,5.78544829e-2,& |
---|
2387 | 8.35491871e-4/) |
---|
2388 | real(krealfp):: cdpk(0:ndpk)=(/1.,8.15968401e-2,5.72839518e-4,& |
---|
2389 | -4.86959812e-7,5.24459889e-10/) |
---|
2390 | integer n |
---|
2391 | real(krealfp) pkpa,fnpk,fdpk |
---|
2392 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2393 | pkpa=p*1.e-3_krealfp |
---|
2394 | fnpk=cnpk(nnpk) |
---|
2395 | do n=nnpk-1,0,-1 |
---|
2396 | fnpk=pkpa*fnpk+cnpk(n) |
---|
2397 | enddo |
---|
2398 | fdpk=cdpk(ndpk) |
---|
2399 | do n=ndpk-1,0,-1 |
---|
2400 | fdpk=pkpa*fdpk+cdpk(n) |
---|
2401 | enddo |
---|
2402 | fpkapo=fnpk/fdpk |
---|
2403 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2404 | end function |
---|
2405 | !------------------------------------------------------------------------------- |
---|
2406 | ! elemental function fpkapx(p) |
---|
2407 | function fpkapx(p) |
---|
2408 | !$$$ Subprogram documentation block |
---|
2409 | ! |
---|
2410 | ! Subprogram: fpkapx raise pressure to the kappa power. |
---|
2411 | ! Author: Phillips org: w/NMC2X2 Date: 29 dec 82 |
---|
2412 | ! |
---|
2413 | ! Abstract: raise pressure over 1e5 Pa to the kappa power. |
---|
2414 | ! Kappa is equal to rd/cp where rd and cp are physical constants. |
---|
2415 | ! This function should be expanded inline in the calling routine. |
---|
2416 | ! |
---|
2417 | ! Program History Log: |
---|
2418 | ! 94-12-30 Iredell made into inlinable function |
---|
2419 | ! 1999-03-01 Iredell f90 module |
---|
2420 | ! |
---|
2421 | ! Usage: pkap=fpkapx(p) |
---|
2422 | ! |
---|
2423 | ! Input argument list: |
---|
2424 | ! p Real(krealfp) pressure in Pascals |
---|
2425 | ! |
---|
2426 | ! Output argument list: |
---|
2427 | ! fpkapx Real(krealfp) p over 1e5 Pa to the kappa power |
---|
2428 | ! |
---|
2429 | ! Attributes: |
---|
2430 | ! Language: Fortran 90. |
---|
2431 | ! |
---|
2432 | !$$$ |
---|
2433 | implicit none |
---|
2434 | real(krealfp) fpkapx |
---|
2435 | real(krealfp),intent(in):: p |
---|
2436 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2437 | fpkapx=(p/1.e5_krealfp)**con_rocp |
---|
2438 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2439 | end function |
---|
2440 | !------------------------------------------------------------------------------- |
---|
2441 | subroutine grkap |
---|
2442 | !$$$ Subprogram documentation block |
---|
2443 | ! |
---|
2444 | ! Subprogram: grkap Compute coefficients for p**(1/kappa) |
---|
2445 | ! Author: Phillips org: w/NMC2X2 Date: 29 dec 82 |
---|
2446 | ! |
---|
2447 | ! Abstract: Computes pressure to the 1/kappa table as a function of pressure |
---|
2448 | ! for the table lookup function frkap. |
---|
2449 | ! Exact pressure to the 1/kappa values are calculated in subprogram frkapx. |
---|
2450 | ! The current implementation computes a table with a length |
---|
2451 | ! of 5501 for pressures ranging up to 110000 Pascals. |
---|
2452 | ! |
---|
2453 | ! Program History Log: |
---|
2454 | ! 94-12-30 Iredell |
---|
2455 | ! 1999-03-01 Iredell f90 module |
---|
2456 | ! 1999-03-24 Iredell table lookup |
---|
2457 | ! |
---|
2458 | ! Usage: call grkap |
---|
2459 | ! |
---|
2460 | ! Subprograms called: |
---|
2461 | ! frkapx function to compute exact pressure to the 1/kappa |
---|
2462 | ! |
---|
2463 | ! Attributes: |
---|
2464 | ! Language: Fortran 90. |
---|
2465 | ! |
---|
2466 | !$$$ |
---|
2467 | implicit none |
---|
2468 | integer jx |
---|
2469 | real(krealfp) xmin,xmax,xinc,x,p |
---|
2470 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2471 | xmin=0._krealfp |
---|
2472 | xmax=fpkapx(110000._krealfp) |
---|
2473 | xinc=(xmax-xmin)/(nxrkap-1) |
---|
2474 | c1xrkap=1.-xmin/xinc |
---|
2475 | c2xrkap=1./xinc |
---|
2476 | do jx=1,nxrkap |
---|
2477 | x=xmin+(jx-1)*xinc |
---|
2478 | p=x |
---|
2479 | tbrkap(jx)=frkapx(p) |
---|
2480 | enddo |
---|
2481 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2482 | end subroutine |
---|
2483 | !------------------------------------------------------------------------------- |
---|
2484 | ! elemental function frkap(pkap) |
---|
2485 | function frkap(pkap) |
---|
2486 | !$$$ Subprogram Documentation Block |
---|
2487 | ! |
---|
2488 | ! Subprogram: frkap raise pressure to the 1/kappa power. |
---|
2489 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
2490 | ! |
---|
2491 | ! Abstract: Raise pressure over 1e5 Pa to the 1/kappa power. |
---|
2492 | ! A linear interpolation is done between values in a lookup table |
---|
2493 | ! computed in grkap. See documentation for frkapx for details. |
---|
2494 | ! Input values outside table range are reset to table extrema. |
---|
2495 | ! The interpolation accuracy is better than 7 decimal places. |
---|
2496 | ! On the IBM, fpkap is about 4 times faster than exact calculation. |
---|
2497 | ! This function should be expanded inline in the calling routine. |
---|
2498 | ! |
---|
2499 | ! Program History Log: |
---|
2500 | ! 91-05-07 Iredell made into inlinable function |
---|
2501 | ! 94-12-30 Iredell standardized kappa, |
---|
2502 | ! increased range and accuracy |
---|
2503 | ! 1999-03-01 Iredell f90 module |
---|
2504 | ! 1999-03-24 Iredell table lookup |
---|
2505 | ! |
---|
2506 | ! Usage: p=frkap(pkap) |
---|
2507 | ! |
---|
2508 | ! Input argument list: |
---|
2509 | ! pkap Real(krealfp) p over 1e5 Pa to the kappa power |
---|
2510 | ! |
---|
2511 | ! Output argument list: |
---|
2512 | ! frkap Real(krealfp) pressure in Pascals |
---|
2513 | ! |
---|
2514 | ! Attributes: |
---|
2515 | ! Language: Fortran 90. |
---|
2516 | ! |
---|
2517 | !$$$ |
---|
2518 | implicit none |
---|
2519 | real(krealfp) frkap |
---|
2520 | real(krealfp),intent(in):: pkap |
---|
2521 | integer jx |
---|
2522 | real(krealfp) xj |
---|
2523 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2524 | xj=min(max(c1xrkap+c2xrkap*pkap,1._krealfp),real(nxrkap,krealfp)) |
---|
2525 | jx=min(xj,nxrkap-1._krealfp) |
---|
2526 | frkap=tbrkap(jx)+(xj-jx)*(tbrkap(jx+1)-tbrkap(jx)) |
---|
2527 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2528 | end function |
---|
2529 | !------------------------------------------------------------------------------- |
---|
2530 | ! elemental function frkapq(pkap) |
---|
2531 | function frkapq(pkap) |
---|
2532 | !$$$ Subprogram Documentation Block |
---|
2533 | ! |
---|
2534 | ! Subprogram: frkapq raise pressure to the 1/kappa power. |
---|
2535 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
2536 | ! |
---|
2537 | ! Abstract: Raise pressure over 1e5 Pa to the 1/kappa power. |
---|
2538 | ! A quadratic interpolation is done between values in a lookup table |
---|
2539 | ! computed in grkap. see documentation for frkapx for details. |
---|
2540 | ! Input values outside table range are reset to table extrema. |
---|
2541 | ! The interpolation accuracy is better than 11 decimal places. |
---|
2542 | ! On the IBM, fpkap is almost 4 times faster than exact calculation. |
---|
2543 | ! This function should be expanded inline in the calling routine. |
---|
2544 | ! |
---|
2545 | ! Program History Log: |
---|
2546 | ! 91-05-07 Iredell made into inlinable function |
---|
2547 | ! 94-12-30 Iredell standardized kappa, |
---|
2548 | ! increased range and accuracy |
---|
2549 | ! 1999-03-01 Iredell f90 module |
---|
2550 | ! 1999-03-24 Iredell table lookup |
---|
2551 | ! |
---|
2552 | ! Usage: p=frkapq(pkap) |
---|
2553 | ! |
---|
2554 | ! Input argument list: |
---|
2555 | ! pkap Real(krealfp) p over 1e5 Pa to the kappa power |
---|
2556 | ! |
---|
2557 | ! Output argument list: |
---|
2558 | ! frkapq Real(krealfp) pressure in Pascals |
---|
2559 | ! |
---|
2560 | ! Attributes: |
---|
2561 | ! Language: Fortran 90. |
---|
2562 | ! |
---|
2563 | !$$$ |
---|
2564 | implicit none |
---|
2565 | real(krealfp) frkapq |
---|
2566 | real(krealfp),intent(in):: pkap |
---|
2567 | integer jx |
---|
2568 | real(krealfp) xj,dxj,fj1,fj2,fj3 |
---|
2569 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2570 | xj=min(max(c1xrkap+c2xrkap*pkap,1._krealfp),real(nxrkap,krealfp)) |
---|
2571 | jx=min(max(nint(xj),2),nxrkap-1) |
---|
2572 | dxj=xj-jx |
---|
2573 | fj1=tbrkap(jx-1) |
---|
2574 | fj2=tbrkap(jx) |
---|
2575 | fj3=tbrkap(jx+1) |
---|
2576 | frkapq=(((fj3+fj1)/2-fj2)*dxj+(fj3-fj1)/2)*dxj+fj2 |
---|
2577 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2578 | end function |
---|
2579 | !------------------------------------------------------------------------------- |
---|
2580 | ! elemental function frkapx(pkap) |
---|
2581 | function frkapx(pkap) |
---|
2582 | !$$$ Subprogram documentation block |
---|
2583 | ! |
---|
2584 | ! Subprogram: frkapx raise pressure to the 1/kappa power. |
---|
2585 | ! Author: Phillips org: w/NMC2X2 Date: 29 dec 82 |
---|
2586 | ! |
---|
2587 | ! Abstract: raise pressure over 1e5 Pa to the 1/kappa power. |
---|
2588 | ! Kappa is equal to rd/cp where rd and cp are physical constants. |
---|
2589 | ! This function should be expanded inline in the calling routine. |
---|
2590 | ! |
---|
2591 | ! Program History Log: |
---|
2592 | ! 94-12-30 Iredell made into inlinable function |
---|
2593 | ! 1999-03-01 Iredell f90 module |
---|
2594 | ! |
---|
2595 | ! Usage: p=frkapx(pkap) |
---|
2596 | ! |
---|
2597 | ! Input argument list: |
---|
2598 | ! pkap Real(krealfp) p over 1e5 Pa to the kappa power |
---|
2599 | ! |
---|
2600 | ! Output argument list: |
---|
2601 | ! frkapx Real(krealfp) pressure in Pascals |
---|
2602 | ! |
---|
2603 | ! Attributes: |
---|
2604 | ! Language: Fortran 90. |
---|
2605 | ! |
---|
2606 | !$$$ |
---|
2607 | implicit none |
---|
2608 | real(krealfp) frkapx |
---|
2609 | real(krealfp),intent(in):: pkap |
---|
2610 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2611 | frkapx=pkap**(1/con_rocp)*1.e5_krealfp |
---|
2612 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2613 | end function |
---|
2614 | !------------------------------------------------------------------------------- |
---|
2615 | subroutine gtlcl |
---|
2616 | !$$$ Subprogram Documentation Block |
---|
2617 | ! |
---|
2618 | ! Subprogram: gtlcl Compute equivalent potential temperature table |
---|
2619 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
2620 | ! |
---|
2621 | ! Abstract: Compute lifting condensation level temperature table |
---|
2622 | ! as a function of temperature and dewpoint depression for function ftlcl. |
---|
2623 | ! Lifting condensation level temperature is calculated in subprogram ftlclx |
---|
2624 | ! The current implementation computes a table with a first dimension |
---|
2625 | ! of 151 for temperatures ranging from 180.0 to 330.0 Kelvin |
---|
2626 | ! and a second dimension of 61 for dewpoint depression ranging from |
---|
2627 | ! 0 to 60 Kelvin. |
---|
2628 | ! |
---|
2629 | ! Program History Log: |
---|
2630 | ! 1999-03-01 Iredell f90 module |
---|
2631 | ! |
---|
2632 | ! Usage: call gtlcl |
---|
2633 | ! |
---|
2634 | ! Subprograms called: |
---|
2635 | ! (ftlclx) inlinable function to compute LCL temperature |
---|
2636 | ! |
---|
2637 | ! Attributes: |
---|
2638 | ! Language: Fortran 90. |
---|
2639 | ! |
---|
2640 | !$$$ |
---|
2641 | implicit none |
---|
2642 | integer jx,jy |
---|
2643 | real(krealfp) xmin,xmax,ymin,ymax,xinc,yinc,x,y,tdpd,t |
---|
2644 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2645 | xmin=180._krealfp |
---|
2646 | xmax=330._krealfp |
---|
2647 | ymin=0._krealfp |
---|
2648 | ymax=60._krealfp |
---|
2649 | xinc=(xmax-xmin)/(nxtlcl-1) |
---|
2650 | c1xtlcl=1.-xmin/xinc |
---|
2651 | c2xtlcl=1./xinc |
---|
2652 | yinc=(ymax-ymin)/(nytlcl-1) |
---|
2653 | c1ytlcl=1.-ymin/yinc |
---|
2654 | c2ytlcl=1./yinc |
---|
2655 | do jy=1,nytlcl |
---|
2656 | y=ymin+(jy-1)*yinc |
---|
2657 | tdpd=y |
---|
2658 | do jx=1,nxtlcl |
---|
2659 | x=xmin+(jx-1)*xinc |
---|
2660 | t=x |
---|
2661 | tbtlcl(jx,jy)=ftlclx(t,tdpd) |
---|
2662 | enddo |
---|
2663 | enddo |
---|
2664 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2665 | end subroutine |
---|
2666 | !------------------------------------------------------------------------------- |
---|
2667 | ! elemental function ftlcl(t,tdpd) |
---|
2668 | function ftlcl(t,tdpd) |
---|
2669 | !$$$ Subprogram Documentation Block |
---|
2670 | ! |
---|
2671 | ! Subprogram: ftlcl Compute LCL temperature |
---|
2672 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
2673 | ! |
---|
2674 | ! Abstract: Compute temperature at the lifting condensation level |
---|
2675 | ! from temperature and dewpoint depression. |
---|
2676 | ! A bilinear interpolation is done between values in a lookup table |
---|
2677 | ! computed in gtlcl. See documentation for ftlclx for details. |
---|
2678 | ! Input values outside table range are reset to table extrema. |
---|
2679 | ! The interpolation accuracy is better than 0.0005 Kelvin. |
---|
2680 | ! On the Cray, ftlcl is ? times faster than exact calculation. |
---|
2681 | ! This function should be expanded inline in the calling routine. |
---|
2682 | ! |
---|
2683 | ! Program History Log: |
---|
2684 | ! 1999-03-01 Iredell f90 module |
---|
2685 | ! |
---|
2686 | ! Usage: tlcl=ftlcl(t,tdpd) |
---|
2687 | ! |
---|
2688 | ! Input argument list: |
---|
2689 | ! t Real(krealfp) LCL temperature in Kelvin |
---|
2690 | ! tdpd Real(krealfp) dewpoint depression in Kelvin |
---|
2691 | ! |
---|
2692 | ! Output argument list: |
---|
2693 | ! ftlcl Real(krealfp) temperature at the LCL in Kelvin |
---|
2694 | ! |
---|
2695 | ! Attributes: |
---|
2696 | ! Language: Fortran 90. |
---|
2697 | ! |
---|
2698 | !$$$ |
---|
2699 | implicit none |
---|
2700 | real(krealfp) ftlcl |
---|
2701 | real(krealfp),intent(in):: t,tdpd |
---|
2702 | integer jx,jy |
---|
2703 | real(krealfp) xj,yj,ftx1,ftx2 |
---|
2704 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2705 | xj=min(max(c1xtlcl+c2xtlcl*t,1._krealfp),real(nxtlcl,krealfp)) |
---|
2706 | yj=min(max(c1ytlcl+c2ytlcl*tdpd,1._krealfp),real(nytlcl,krealfp)) |
---|
2707 | jx=min(xj,nxtlcl-1._krealfp) |
---|
2708 | jy=min(yj,nytlcl-1._krealfp) |
---|
2709 | ftx1=tbtlcl(jx,jy)+(xj-jx)*(tbtlcl(jx+1,jy)-tbtlcl(jx,jy)) |
---|
2710 | ftx2=tbtlcl(jx,jy+1)+(xj-jx)*(tbtlcl(jx+1,jy+1)-tbtlcl(jx,jy+1)) |
---|
2711 | ftlcl=ftx1+(yj-jy)*(ftx2-ftx1) |
---|
2712 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2713 | end function |
---|
2714 | !------------------------------------------------------------------------------- |
---|
2715 | ! elemental function ftlclq(t,tdpd) |
---|
2716 | function ftlclq(t,tdpd) |
---|
2717 | !$$$ Subprogram Documentation Block |
---|
2718 | ! |
---|
2719 | ! Subprogram: ftlclq Compute LCL temperature |
---|
2720 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
2721 | ! |
---|
2722 | ! Abstract: Compute temperature at the lifting condensation level |
---|
2723 | ! from temperature and dewpoint depression. |
---|
2724 | ! A biquadratic interpolation is done between values in a lookup table |
---|
2725 | ! computed in gtlcl. see documentation for ftlclx for details. |
---|
2726 | ! Input values outside table range are reset to table extrema. |
---|
2727 | ! The interpolation accuracy is better than 0.000003 Kelvin. |
---|
2728 | ! On the Cray, ftlclq is ? times faster than exact calculation. |
---|
2729 | ! This function should be expanded inline in the calling routine. |
---|
2730 | ! |
---|
2731 | ! Program History Log: |
---|
2732 | ! 1999-03-01 Iredell f90 module |
---|
2733 | ! |
---|
2734 | ! Usage: tlcl=ftlclq(t,tdpd) |
---|
2735 | ! |
---|
2736 | ! Input argument list: |
---|
2737 | ! t Real(krealfp) LCL temperature in Kelvin |
---|
2738 | ! tdpd Real(krealfp) dewpoint depression in Kelvin |
---|
2739 | ! |
---|
2740 | ! Output argument list: |
---|
2741 | ! ftlcl Real(krealfp) temperature at the LCL in Kelvin |
---|
2742 | ! |
---|
2743 | ! Attributes: |
---|
2744 | ! Language: Fortran 90. |
---|
2745 | ! |
---|
2746 | !$$$ |
---|
2747 | implicit none |
---|
2748 | real(krealfp) ftlclq |
---|
2749 | real(krealfp),intent(in):: t,tdpd |
---|
2750 | integer jx,jy |
---|
2751 | real(krealfp) xj,yj,dxj,dyj |
---|
2752 | real(krealfp) ft11,ft12,ft13,ft21,ft22,ft23,ft31,ft32,ft33 |
---|
2753 | real(krealfp) ftx1,ftx2,ftx3 |
---|
2754 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2755 | xj=min(max(c1xtlcl+c2xtlcl*t,1._krealfp),real(nxtlcl,krealfp)) |
---|
2756 | yj=min(max(c1ytlcl+c2ytlcl*tdpd,1._krealfp),real(nytlcl,krealfp)) |
---|
2757 | jx=min(max(nint(xj),2),nxtlcl-1) |
---|
2758 | jy=min(max(nint(yj),2),nytlcl-1) |
---|
2759 | dxj=xj-jx |
---|
2760 | dyj=yj-jy |
---|
2761 | ft11=tbtlcl(jx-1,jy-1) |
---|
2762 | ft12=tbtlcl(jx-1,jy) |
---|
2763 | ft13=tbtlcl(jx-1,jy+1) |
---|
2764 | ft21=tbtlcl(jx,jy-1) |
---|
2765 | ft22=tbtlcl(jx,jy) |
---|
2766 | ft23=tbtlcl(jx,jy+1) |
---|
2767 | ft31=tbtlcl(jx+1,jy-1) |
---|
2768 | ft32=tbtlcl(jx+1,jy) |
---|
2769 | ft33=tbtlcl(jx+1,jy+1) |
---|
2770 | ftx1=(((ft31+ft11)/2-ft21)*dxj+(ft31-ft11)/2)*dxj+ft21 |
---|
2771 | ftx2=(((ft32+ft12)/2-ft22)*dxj+(ft32-ft12)/2)*dxj+ft22 |
---|
2772 | ftx3=(((ft33+ft13)/2-ft23)*dxj+(ft33-ft13)/2)*dxj+ft23 |
---|
2773 | ftlclq=(((ftx3+ftx1)/2-ftx2)*dyj+(ftx3-ftx1)/2)*dyj+ftx2 |
---|
2774 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2775 | end function |
---|
2776 | !------------------------------------------------------------------------------- |
---|
2777 | function ftlclo(t,tdpd) |
---|
2778 | !$$$ Subprogram documentation block |
---|
2779 | ! |
---|
2780 | ! Subprogram: ftlclo Compute LCL temperature. |
---|
2781 | ! Author: Phillips org: w/NMC2X2 Date: 29 dec 82 |
---|
2782 | ! |
---|
2783 | ! Abstract: Compute temperature at the lifting condensation level |
---|
2784 | ! from temperature and dewpoint depression. the formula used is |
---|
2785 | ! a polynomial taken from Phillips mstadb routine which empirically |
---|
2786 | ! approximates the original exact implicit relationship. |
---|
2787 | ! (This kind of approximation is customary (inman, 1969), but |
---|
2788 | ! the original source for this particular one is not yet known. -MI) |
---|
2789 | ! Its accuracy is about 0.03 Kelvin for a dewpoint depression of 30. |
---|
2790 | ! This function should be expanded inline in the calling routine. |
---|
2791 | ! |
---|
2792 | ! Program History Log: |
---|
2793 | ! 91-05-07 Iredell made into inlinable function |
---|
2794 | ! 1999-03-01 Iredell f90 module |
---|
2795 | ! |
---|
2796 | ! Usage: tlcl=ftlclo(t,tdpd) |
---|
2797 | ! |
---|
2798 | ! Input argument list: |
---|
2799 | ! t Real(krealfp) temperature in Kelvin |
---|
2800 | ! tdpd Real(krealfp) dewpoint depression in Kelvin |
---|
2801 | ! |
---|
2802 | ! Output argument list: |
---|
2803 | ! ftlclo Real(krealfp) temperature at the LCL in Kelvin |
---|
2804 | ! |
---|
2805 | ! Attributes: |
---|
2806 | ! Language: Fortran 90. |
---|
2807 | ! |
---|
2808 | !$$$ |
---|
2809 | implicit none |
---|
2810 | real(krealfp) ftlclo |
---|
2811 | real(krealfp),intent(in):: t,tdpd |
---|
2812 | real(krealfp),parameter:: clcl1= 0.954442e+0,clcl2= 0.967772e-3,& |
---|
2813 | clcl3=-0.710321e-3,clcl4=-0.270742e-5 |
---|
2814 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2815 | ftlclo=t-tdpd*(clcl1+clcl2*t+tdpd*(clcl3+clcl4*t)) |
---|
2816 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2817 | end function |
---|
2818 | !------------------------------------------------------------------------------- |
---|
2819 | ! elemental function ftlclx(t,tdpd) |
---|
2820 | function ftlclx(t,tdpd) |
---|
2821 | !$$$ Subprogram documentation block |
---|
2822 | ! |
---|
2823 | ! Subprogram: ftlclx Compute LCL temperature. |
---|
2824 | ! Author: Iredell org: w/NMC2X2 Date: 25 March 1999 |
---|
2825 | ! |
---|
2826 | ! Abstract: Compute temperature at the lifting condensation level |
---|
2827 | ! from temperature and dewpoint depression. A parcel lifted |
---|
2828 | ! adiabatically becomes saturated at the lifting condensation level. |
---|
2829 | ! The water model assumes a perfect gas, constant specific heats |
---|
2830 | ! for gas and liquid, and neglects the volume of the liquid. |
---|
2831 | ! The model does account for the variation of the latent heat |
---|
2832 | ! of condensation with temperature. The ice option is not included. |
---|
2833 | ! The Clausius-Clapeyron equation is integrated from the triple point |
---|
2834 | ! to get the formulas |
---|
2835 | ! pvlcl=con_psat*(trlcl**xa)*exp(xb*(1.-trlcl)) |
---|
2836 | ! pvdew=con_psat*(trdew**xa)*exp(xb*(1.-trdew)) |
---|
2837 | ! where pvlcl is the saturated parcel vapor pressure at the LCL, |
---|
2838 | ! pvdew is the unsaturated parcel vapor pressure initially, |
---|
2839 | ! trlcl is ttp/tlcl and trdew is ttp/tdew. The adiabatic lifting |
---|
2840 | ! of the parcel is represented by the following formula |
---|
2841 | ! pvdew=pvlcl*(t/tlcl)**(1/kappa) |
---|
2842 | ! This formula is inverted by iterating Newtonian approximations |
---|
2843 | ! until tlcl is found to within 1.e-6 Kelvin. Note that the minimum |
---|
2844 | ! returned temperature is 180 Kelvin. |
---|
2845 | ! |
---|
2846 | ! Program History Log: |
---|
2847 | ! 1999-03-25 Iredell |
---|
2848 | ! |
---|
2849 | ! Usage: tlcl=ftlclx(t,tdpd) |
---|
2850 | ! |
---|
2851 | ! Input argument list: |
---|
2852 | ! t Real(krealfp) temperature in Kelvin |
---|
2853 | ! tdpd Real(krealfp) dewpoint depression in Kelvin |
---|
2854 | ! |
---|
2855 | ! Output argument list: |
---|
2856 | ! ftlclx Real(krealfp) temperature at the LCL in Kelvin |
---|
2857 | ! |
---|
2858 | ! Attributes: |
---|
2859 | ! Language: Fortran 90. |
---|
2860 | ! |
---|
2861 | !$$$ |
---|
2862 | implicit none |
---|
2863 | real(krealfp) ftlclx |
---|
2864 | real(krealfp),intent(in):: t,tdpd |
---|
2865 | real(krealfp),parameter:: terrm=1.e-4,tlmin=180.,tlminx=tlmin-5. |
---|
2866 | real(krealfp) tr,pvdew,tlcl,ta,pvlcl,el,dpvlcl,terr,terrp |
---|
2867 | integer i |
---|
2868 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2869 | tr=con_ttp/(t-tdpd) |
---|
2870 | pvdew=con_psat*(tr**con_xpona)*exp(con_xponb*(1.-tr)) |
---|
2871 | tlcl=t-tdpd |
---|
2872 | do i=1,100 |
---|
2873 | tr=con_ttp/tlcl |
---|
2874 | ta=t/tlcl |
---|
2875 | pvlcl=con_psat*(tr**con_xpona)*exp(con_xponb*(1.-tr))*ta**(1/con_rocp) |
---|
2876 | el=con_hvap+con_dldt*(tlcl-con_ttp) |
---|
2877 | dpvlcl=(el/(con_rv*t**2)+1/(con_rocp*tlcl))*pvlcl |
---|
2878 | terr=(pvlcl-pvdew)/dpvlcl |
---|
2879 | tlcl=tlcl-terr |
---|
2880 | if(abs(terr).le.terrm.or.tlcl.lt.tlminx) exit |
---|
2881 | enddo |
---|
2882 | ftlclx=max(tlcl,tlmin) |
---|
2883 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2884 | end function |
---|
2885 | !------------------------------------------------------------------------------- |
---|
2886 | subroutine gfuncphys |
---|
2887 | !$$$ Subprogram Documentation Block |
---|
2888 | ! |
---|
2889 | ! Subprogram: gfuncphys Compute all physics function tables |
---|
2890 | ! Author: N Phillips w/NMC2X2 Date: 30 dec 82 |
---|
2891 | ! |
---|
2892 | ! Abstract: Compute all physics function tables. Lookup tables are |
---|
2893 | ! set up for computing saturation vapor pressure, dewpoint temperature, |
---|
2894 | ! equivalent potential temperature, moist adiabatic temperature and humidity, |
---|
2895 | ! pressure to the kappa, and lifting condensation level temperature. |
---|
2896 | ! |
---|
2897 | ! Program History Log: |
---|
2898 | ! 1999-03-01 Iredell f90 module |
---|
2899 | ! |
---|
2900 | ! Usage: call gfuncphys |
---|
2901 | ! |
---|
2902 | ! Subprograms called: |
---|
2903 | ! gpvsl compute saturation vapor pressure over liquid table |
---|
2904 | ! gpvsi compute saturation vapor pressure over ice table |
---|
2905 | ! gpvs compute saturation vapor pressure table |
---|
2906 | ! gtdpl compute dewpoint temperature over liquid table |
---|
2907 | ! gtdpi compute dewpoint temperature over ice table |
---|
2908 | ! gtdp compute dewpoint temperature table |
---|
2909 | ! gthe compute equivalent potential temperature table |
---|
2910 | ! gtma compute moist adiabat tables |
---|
2911 | ! gpkap compute pressure to the kappa table |
---|
2912 | ! grkap compute pressure to the 1/kappa table |
---|
2913 | ! gtlcl compute LCL temperature table |
---|
2914 | ! |
---|
2915 | ! Attributes: |
---|
2916 | ! Language: Fortran 90. |
---|
2917 | ! |
---|
2918 | !$$$ |
---|
2919 | implicit none |
---|
2920 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2921 | call gpvsl |
---|
2922 | call gpvsi |
---|
2923 | call gpvs |
---|
2924 | call gtdpl |
---|
2925 | call gtdpi |
---|
2926 | call gtdp |
---|
2927 | call gthe |
---|
2928 | call gtma |
---|
2929 | call gpkap |
---|
2930 | call grkap |
---|
2931 | call gtlcl |
---|
2932 | ! - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - |
---|
2933 | end subroutine |
---|
2934 | !------------------------------------------------------------------------------- |
---|
2935 | end module module_gfs_funcphys |
---|