getTrend: Temperature trend during a frost night.

In frost: Prediction of Minimum Temperature for Frost Forecasting in Agriculture

Description

Predict the trend of the temperature during a frost night. This equation has been taken from UC Davis formula [1] which was also published in the FAO book mentioned in predFAO function.

[1] <http://biomet.ucdavis.edu/frostprotection/fp002.htm>

Usage

getTrend(Tmin, t2, n, plot = FALSE)

Arguments

Tmin	predicted minimum temperature.
t2	temperature 2 hours after sunset, where t2 > Tmin
n	how many hours between sunset and sunrise, an integer value where n > 2
plot	TRUE if you want to see the trend plot, otherwise FALSE. Default value: FALSE

Value

A data frame with the (x,y) points plotted, where y values are the n-2 values of estimated temperatures

Examples

getTrend(Tmin = 22.2,t2 = 33.7,n = 15) # in <c2><b0>F degress
getTrend(Tmin = -5.45,t2 = 0.95,n = 15,plot=TRUE) # in <c2><b0>C degress

Example output

    x        y
1   3 30.51047
2   4 29.18933
3   5 28.17558
4   6 27.32095
5   7 26.56800
6   8 25.88729
7   9 25.26131
8  10 24.67866
9  11 24.13142
10 12 23.61383
11 13 23.12154
12 14 22.65116
13 15 22.20000
    x          y
1   3 -0.8250406
2   4 -1.5602865
3   5 -2.1244606
4   6 -2.6000813
5   7 -3.0191115
6   8 -3.3979438
7   9 -3.7463161
8  10 -4.0705731
9  11 -4.3751219
10 12 -4.6631713
11 13 -4.9371438
12 14 -5.1989211
13 15 -5.4500000

frost documentation built on May 2, 2019, 10:19 a.m.