etp_th: Potential evapo-transpiration sensu Thorntwaite (1948)

In achtmalklug/Retp:

Description

WARNING: IMPLEMENTATION IS PRELIMINARY. RESULTS PROBABLY WRONG. Especially for higher latitudes.

Calculates monthly potential evapo-transpiration in using the approach by Thorntwaite (1948).

Usage

etp_th(lat, dates, temp, fillmethod = na.approx)

Arguments

lat	latitude (used for calculating daylight hours)
temp	air temperature (°C) for the given dates.
fillmethod	na.approx or na.spline, used inter- and extrapolate insufficient values to the whole year.
date	either a vector of dates (class "Date") or a julian day (numeric). Since the Thorntwaite method is based on an annual heat index, dates should cover the whole year.

Value

ra Potential evapo-transpiration in mm/d.

Examples

etp_th(lat=54,temp=c(1,14,1),dates=c(1,210,365))

achtmalklug/Retp documentation built on June 7, 2019, 12:47 a.m.