Crop Water Stress Index (CWSI)

Computes the Crop Water Stress Index based on the ratio of actual to potential evapotranspiration.

crop_water_stress_index(actual_et, potential_et, verbose = TRUE)

Arguments

actual_et

Numeric vector. Actual evapotranspiration (mm).

potential_et

Numeric vector. Potential or reference evapotranspiration (mm).

verbose

Logical. If TRUE, prints informational messages. Default TRUE.

Value

Numeric vector. CWSI values between 0 (no stress) and 1 (maximum stress). Values close to 0 indicate well-watered conditions; values close to 1 indicate severe water deficit.

Details

$$CWSI = 1 - \frac{ET_a}{ET_p}$$

References

Idso, S.B. et al. (1981). Normalizing the stress-degree-day parameter for environmental variability. Agricultural Meteorology, 24, 45-55. doi:10.1016/0002-1571(81)90032-7

Examples

crop_water_stress_index(c(4.5, 3.8, 3.0, 2.2), c(5.0, 5.0, 5.0, 5.0))
#> CWSI computed: 4 values.
#> [1] 0.10 0.24 0.40 0.56