chillR (version 0.72.2)

Utah_Model: Calculation of cumulative chill according to the Utah Model

Description

This function calculates winter chill for temperate trees according to the Utah Model.

Usage

Utah_Model(HourTemp, summ = TRUE)

Arguments

HourTemp

Vector of hourly temperatures.

summ

Boolean parameter indicating whether calculated metrics should be provided as cumulative values over the entire record (TRUE) or as the actual accumulation for each hour (FALSE).

Value

Vector of length length(HourTemp) containing the cumulative Utah Chill Units over the entire duration of HourTemp.

Details

Units of the Utah Model are calculated as suggested by Richardson et al. (1974) (different weights for different temperature ranges, and negation of chilling by warm temperatures).

References

Utah Model reference:

Richardson EA, Seeley SD, Walker DR (1974) A model for estimating the completion of rest for Redhaven and Elberta peach trees. HortScience 9(4), 331-332

Examples

# NOT RUN {
weather<-fix_weather(KA_weather[which(KA_weather$Year>2006),])

stack<-stack_hourly_temps(weather,latitude=50.4)

Utah_Model(stack$hourtemps$Temp)

# }