freezedates {springpheno} | R Documentation |
Freeze Date Calculator
Description
This function determines when freezes occur during the year given the daily low temperature data, freeze threshold, and the day of year.
Usage
freezedates(tasmin, frzval, DOY)
Arguments
tasmin |
Vector - daily low temperature data (degrees Fahrenheit). The vector should have a length of 366. |
frzval |
Scalar - freeze threshold (degrees Fahrenheit). Typically this is 28F. |
DOY |
Vector - day of year (1:366) |
Value
The output from this function is a list with the following:
firstfreeze |
Scalar - day of year matching the first freeze that occurs in the fall. |
lastfreeze |
Scalar - day of year matching the last freeze that occurs in the spring. |
freezeperiod |
Scalar - range of days between the first and last freeze. |
freezedata |
Data Frame - Table containing the values for low temperature (tasmin), Day of year (DOY), and adjusted Day of Year (DOYadj) for those days of the year where a freeze occurs. |
Author(s)
Adrienne M. Wootten (University of Oklahoma)