monthlyPET: monthly PET

In envirem: Generation of ENVIREM Variables

monthly PET

Description

Monthly potential evapotranspiration

Usage

monthlyPET(Tmean, RA, TD, tempScale = 1)

Arguments

Tmean	SpatRaster of monthly mean temperature
RA	SpatRaster of monthly extraterrestrial solar radiation
TD	SpatRaster of monthly temperature range
tempScale	integer; scaling factor for the temperature data, see envirem for additional details.

Details

PET = 0.0023 * RA * (Tmean + 17.8) * TD ^ 0.5

Value

SpatRaster of monthly PET in mm / month

Author(s)

Pascal Title

References

Hargreaves, G. L., Hargreaves, G. H., & Riley, J. P. (1985). Irrigation water requirements for Senegal River basin. Journal of Irrigation and Drainage Engineering, 111, 265-275.

Zomer, R.J., Trabucco, A., Bossio, D.A. & Verchot, L.V. (2008). Climate change mitigation: A spatial analysis of global land suitability for clean development mechanism afforestation and reforestation. Agriculture, Ecosystems and Environment, 126, 67-80.

Zomer, R.J., Trabucco, A., Van Straaten, O. & Bossio, D.A. (2006) Carbon, Land and Water: A Global Analysis of the Hydrologic Dimensions of Climate Change Mitigation through Afforestation/Reforestation. International Water Management Institute Research Report 101. Colombo, Sri Lanka.

Examples

# Find example rasters
rasterFiles <- list.files(system.file('extdata', package='envirem'), full.names=TRUE)
env <- rast(rasterFiles)

# identify the appropriate layers
meantemp <- grep('mean', names(env), value=TRUE)
solar <- grep('solrad', names(env), value=TRUE)
maxtemp <- grep('tmax', names(env), value=TRUE)
mintemp <- grep('tmin', names(env), value=TRUE)

# read them in as SpatRasters
meantemp <- env[[meantemp]]
solar <- env[[solar]]
maxtemp <- env[[maxtemp]]
mintemp <- env[[mintemp]]
tempRange <- abs(maxtemp - mintemp)

monthlyPET(meantemp, solar, tempRange, tempScale = 10)

envirem documentation built on Aug. 26, 2023, 1:07 a.m.