aiRthermo (version 1.1)

AnyAdiabaticDown: Adiabatic Downwards Evolution

Description

Calculation of the state of an air parcel subject to an adiabatic downwards evolution, taking into account the initial conditions of the parcel (Pstart, Tstart, wstart, wcstart).

Usage

AnyAdiabaticDown(Pstart, Tstart, wstart, wcstart, Pend, deltaP)

Arguments

Pstart

Initial pressure value (Pa)

Tstart

Initial temperature value (K)

wstart

Initial mixing ratio value (kg/kg)

wcstart

Initial mixing ratio value for the condensates (kg/kg)

Pend

Final pressure value (Pa)

deltaP

Pressure step used for the calculation. It must be a positive value (Pa)

Value

This function returns a list including the following values:

Tend

Temperature at the end (K)

Wend

Mixing ratio of water vapour at the end (kg/kg)

Wcend

Mixing ratio of condensed water at the end (kg/kg)

Details

In this case, we start from a parcel at pressure pstart (Pa), temperature tstart (K) and mixing ratio wstart (kg/kg), with potentially some condensates wcstart (kg/kg). The latent heat (L) used during the evolution depends on the Temperature (T). It is computed as described by latent_heat_H2O. As the parcel goes down it could evaporate the condensates or, if no condensates are available anymore, it will go down according to a dry adiabatic evolution by means of a dry adiabatic process until the level Pend. At this point, it will have a temperature Tend, mixing ratio (vapour) Wend and Wcend (may be still some condensates could be left) using steps of pressure dP (always positive).

Examples

Run this code
# NOT RUN {
AnyAdiabaticDown(50000,227,8.5e-5,0.005,101325,5)
AnyAdiabaticDown(70000,237,4e-4,0.005,101325,5)
# }

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