% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/drought.R
\name{ck_pet}
\alias{ck_pet}
\title{Potential Evapotranspiration (Hargreaves Method)}
\usage{
ck_pet(tmin, tmax, lat, dates)
}
\arguments{
\item{tmin}{Numeric vector of daily minimum temperatures (degrees C).}

\item{tmax}{Numeric vector of daily maximum temperatures (degrees C).}

\item{lat}{Numeric. Latitude in decimal degrees.}

\item{dates}{Date vector of the same length as \code{tmin}.}
}
\value{
A data frame with columns \code{date}, \code{value}, \code{index}, and \code{unit}.
}
\description{
Estimate daily PET using the Hargreaves-Samani equation, which requires
only daily temperature extremes and latitude.
}
\examples{
dates <- as.Date("2024-07-01") + 0:9
tmin <- c(15, 16, 14, 17, 15, 13, 16, 14, 15, 16)
tmax <- c(30, 32, 28, 33, 31, 27, 34, 29, 30, 32)
ck_pet(tmin, tmax, lat = 45, dates = dates)
}
\references{
Hargreaves, G. H., & Samani, Z. A. (1985). Reference crop
evapotranspiration from temperature. \emph{Applied Engineering in Agriculture},
1(2), 96-99.
}
