fruclimadapt (version 0.4.5)

coolness_index: Calculation of night coolness index

Description

This function calculates a night coolness index based in the Cool Night index of Tonietto (1999). Instead of calculating the mean of minimum temperatures in September/March (Northern or Southern hemispheres, respectively), this function allows to define the harvest date and the number of days that will be analyzed (by default, 30 days), and calculates the mean of minimum temperatures in the in the specified period of days before harvest. The function allows testing for several harvest dates simultaneously.

Usage

coolness_index(climdata, harvest, span = 30)

Value

dataframe with the values of the indices. It contains the columns Year, Harvest, Coolness

Arguments

climdata

a dataframe with daily maximum and minimum temperatures. Must contain the columns Year, Month, Day, Tmax, Tmin.

harvest

a vector with expected harvest days (expressed as day of the year)

span

the period (in days) before harvest that will be analyzed. By default, this parameter is set in 30 days.

Author

Carlos Miranda,

References

Tonietto J. 1999. Les macroclimats viticoles mondiaux et l'influence du mésoclimat sur la typicité de la Syrah et du Muscat de Hambourg dans le sud de la France: methodologie de carácterisation. Thése Doctorat. Ecole Nationale Supérieure Agronomique, Montpellier, 233pp.

Examples

# Select the appropiate columns from the Tudela_DW example dataset,
# create a vector or harvest dates and estimate the coolness index 
# for the 30 days prior to harvest on each year in the dataset.
library(magrittr)
library(dplyr)
Weather <- Tudela_DW %>%
   select(Year, Month, Day, Tmax, Tmin) %>% 
   filter (Tudela_DW$Year<=2002)
harvest <- c(225, 250, 275)
coolness <- coolness_index(Weather, harvest)