MATWM: PERICLIMv1.0::MATWM

In tomasuxa/PERICLIMv1.0: PERICLIMv1.0: A model deriving palaeo-air temperatures from thaw depth in past permafrost regions

Description

Derivation of palaeo-air temperature characteristics from palaeo-active-layer thickness with the magnitude of annual air temperature oscillations defined by the mean air temperature of the warmest month (MATWM), or rather its difference from the mean annual air temperature.

Usage

MATWM(xi, phi, rho, q, fc = c('fine','coarse'), nt, MATWM, showInputs = TRUE)

Arguments

xi	Palaeo-active-layer thickness [m]
phi	Volumetric ground moisture content [–]
rho	Dry ground bulk density [kg/m3]
q	Ground quartz content [–]
fc	Ground grain-size class [–]
nt	Ground-surface thawing n-factor [–]
MATWM	Mean air temperature of the warmest month [degC]
showInputs = TRUE	Should the inputs be included among the outputs (TRUE by default)?

Details

All the numerical inputs (except of the quartz content) must be greater than 0. The moisture and quartz contents must be given as a decimal number with a maximum value of 1. A maximum allowed value for the bulk density is set at 2700 kg/m3.

Value

MAAT	Mean annual air temperature [degC]
MATWM	Mean air temperature of the warmest month [degC]
MATCM	Mean air temperature of the coldest month [degC]
MATTS	Mean air temperature of the thawing season [degC]
MATFS	Mean air temperature of the freezing season [degC]
Ita	Air thawing index [degC.d]
Ifa	Air freezing index [degC.d]
Lt	Length of the thawing season [d]
Lf	Length of the freezing season [d]
Its	Ground-surface thawing index [degC.d]

Warning

This solution should be utilized cautiously because it is highly sensitive to uncertainties in the air thawing index as well as the mean air temperature of the warmest month.

Examples

# Example code run with sample data:

PERICLIMv1.0::MATWM(xi = 0.5, phi = 0.3, rho = 1500, q = 0.4, fc = 'fine', nt = 1.2, MATWM = 1.9, showInputs = TRUE)

# If executed correctly, the output and input variables should be:

# MAAT  = -8.06965559495226
# MATWM = 1.9
# MATCM = -18.0393111899045
# MATTS = 1.25823408572454
# MATFS = -10.3984330754712
# Ita   = 91.7503875413873
# Ifa   = -3037.17467969896
# Lt    = 72.9199666281127
# Lf    = 292.080033371887
# Its   = 110.100465049665
# xi     = 0.5
# phi   = 0.3
# rho   = 1500
# q     = 0.4
# fc    = 'fine'
# kt    = 1.31666362819073
# nt    = 1.2
# Aa    = 19.9393111899045

tomasuxa/PERICLIMv1.0 documentation built on April 13, 2021, 11:43 a.m.