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Compute Reference evapotranspiration (ETo)

ETo_cal.Rd

Function to compute Reference evapotranspiration (ETo) estimates using different methods.

Usage

ETo_cal(wth_data, lat, elev, ref_ht = 2, kRs = 0.175, ws_mean = 2)

Arguments

wth_data

A data frame containing weather data with columns: date, tmax, tmin, rain, rhum, srad, wspd (optional)

lat

Numeric. Latitude (decimal degrees)

elev

Numeric. Elevation (meters above sea level)

ref_ht

Numeric. Sensors reference height.

kRs

Numeric. Hargreaves empirical coefficient, Coastal coefficient

ws_mean

Numeric. Wind Speed Mean, default = 2 m/s

Value

This function returns a numeric vector representing ET0 values (mm).

Examples

# Compute ETo with provided weather data
ETo_cal(wth_data = weather, lat = 3.8, elev = 650) |>
head(10)
#> Reference evapotranspiration (ETo) Method: FAO Penman-Monteith equation
#>  [1] 4.085653 4.105157 4.891880 4.419465 4.991884 4.777290 4.929282 4.264894
#>  [9] 5.026964 4.995741

# Compute into dplyr::mutate

weather %>% slice(1:10) %>%
  mutate(ETo = ETo_cal(., lat = 3.8, elev = 650))
#> Error in weather %>% slice(1:10) %>% mutate(ETo = ETo_cal(., lat = 3.8,     elev = 650)): could not find function "%>%"