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module q_sat_m |
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IMPLICIT none |
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|
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contains |
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elemental real function q_sat(temp, pres) |
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! From dyn3d/q_sat.F, version 1.1.1.1 2004/05/19 12:53:05 |
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! Author: Z. X. Li (LMD/CNRS). |
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! Récriture vectorisée par F. Hourdin. |
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! This procedure computes the mass fraction of saturating water |
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! vapor, with the formula of ECMWF. |
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REAL, intent(in):: temp ! temperature, in K |
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REAL, intent(in):: pres ! total pressure, in Pa |
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! Variables local to the procedure: |
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REAL, PARAMETER:: r2es = 611.14 * 18.0153 / 28.9644 |
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REAL r3es |
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REAL, PARAMETER:: R3LES=17.269 |
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REAL, PARAMETER:: R3IES=21.875 |
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REAL r4es |
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REAL, PARAMETER:: R4LES=35.86 |
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REAL, PARAMETER:: R4IES=7.66 |
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REAL, PARAMETER:: rtt = 273.16 |
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REAL, PARAMETER:: retv = 28.9644 / 18.0153 - 1. |
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!------------------------------------------------------------------ |
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IF (temp <= rtt) THEN |
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r3es = r3ies |
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r4es = r4ies |
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ELSE |
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r3es = r3les |
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r4es = r4les |
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ENDIF |
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|
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q_sat = r2es / pres * EXP(r3es * (temp - rtt) / (temp - r4es)) |
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q_sat = MIN(0.5, q_sat) |
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q_sat = q_sat / (1. - retv * q_sat) |
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END function q_sat |
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end module q_sat_m |
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