springpheno (version 0.5.0)

growdh: Growing Degree Hours Calculator

Description

Given appropriate inputs, this function calculates the growing degree hours for a given day and locations. The formula is also retained from the original Matlab code for the extended spring indices (SI-x, Ault et al. 2015).

Usage

growdh(tmax, tmin, daylen, baset)

Arguments

tmax

Scalar - daily high temperature (degrees Fahrenheit) for a given day

tmin

Scalar - daily low temperature (degrees Fahrenheit) for a given day

daylen

Scalar - day length for a given day (calculated from daylength function)

baset

Scalar - base temperature for determining growing degree hours. Typically this 31 degrees Fahrenheit

Value

GDHOUR - scalar, total growing degree hours for a given day.

References

Ault, T.R., R. Zurita-Miller and M. Schwarz, 2015: A Matlab<U+00A9> toolbox for calculating spring indices from daily meteorological data. Computers and Geosciences, 83, DOI: 10.1016/j.cageo.2015.06.015

Examples

# NOT RUN {
daystop <- 366
lat <- 35.476 # latitude for OKC
daylen <- daylength(daystop=daystop,lat=lat)

tmax <- 65
tmin <- 42
dlen <- daylen[60]
bt <- 31

result <- growdh(tmax,tmin,dlen,bt)

# }