gseason: gseason: Calculates the period where plant growth is possible

In ilyamaclean/climvars: Functions for calculating biologically meaningful climate variables

Description

gseason calculates total annual growing hours where temperatures are within defined upper and lower limits and precipitation exceeds half potential evapotranspiration.

Usage

gseason(year, precipnc, evapnc, tempnc, period = "monthly",
  surplus = TRUE, lower = 5, upper = 35, nday = 1/24,
  daynight = TRUE, merid = 0, dst = 0)

Arguments

year	calendar year.
precipnc	nc file containing precipitation values.
evapnc	nc file containing evpotranspiration values.
tempnc	nc file containing temperature values.
period	an optional character string defining time period of precipitation and evapotranspiration measurements. Options include "monthly" and "bimonthly". If left unspecified, assumed 'submonthly'.
surplus	either TRUE or FALSE.
lower	defines lower temperature limit where plant growth ceases (degrees Celcius) and growing season is switched off.
upper	defines upper temeprature limit where plant growth ceases (degrees Celcius) and growing season is switched off.
nday	specifies the number of consecutive days of temperatures above 'lower' or below 'upper' before growing season start/end is accepted.
daynight	if TRUE, growing season is continuous over 24 hours, if FALSE, only calculates growing season during the day.
merid	an optional numeric value representing the longitude (decimal degrees) of the local time zone meridian (0 for GMT). Default is 0.
dst	an optional numeric value representing the time difference from the timezone meridian (hours, e.g. +1 for BST if merid = 0). Default is 0.

Details

The growing season period is defined as the period where temperatures are >5 degree Celcius and <35 degree Celcius and precipitation > 0.5 PET.

Value

a three dimensional array of binary values indicating growing conditions (1) = yes, (0) = no.

See Also

gseason_prec() calculates period where precipitation exceeds half evapotranspiration.

gseason_temp() calculates period where temperature are above lower limit for plant growth and below upper limit for plant growth.

gseason_day() calculates day/night time.

tmecreate() can be used to create a POSIXlt object.

nctoarray() can be used to create an nc file from array output.

ilyamaclean/climvars documentation built on June 19, 2019, 2:22 p.m.