get_chirts: Get CHIRTS temperature data data

In chirps: API Client for CHIRPS and CHIRTS

Description

Get daily maximum and minimum temperature data from the "Climate Hazards Group". CHIRTS-daily is a global 2-m temperature product that combines the monthly CHIRTSmax data set with the ERA5 reanalysis to produce routinely updated data to support the monitoring of temperature extreme. Data is currently available from 1983 to 2016. Soon available to near-present.

Usage

get_chirts(object, dates, var, ...)

## Default S3 method:
get_chirts(object, dates, var, as.matrix = FALSE, ...)

## S3 method for class 'SpatVector'
get_chirts(object, dates, var, as.raster = TRUE, ...)

## S3 method for class 'SpatRaster'
get_chirts(object, dates, var, as.raster = TRUE, ...)

Arguments

object	an object of class data.frame (or any other object that can be coerced to a data.frame), SpatVector, or SpatRaster
dates	a character of start and end dates in that order in the format "YYYY-MM-DD"
var	character, A valid variable from the options: “Tmax”, “Tmin”, “RHum” and “HeatIndex”
...	additional arguments passed to terra
as.matrix	logical, returns an object of class matrix
as.raster	logical, returns an object of class SpatRaster

Details

Variable description from https://data.chc.ucsb.edu/products/CHIRTSdaily/aaa.Readme.txt

Tmax

Daily average maximum air temperature at 2 m above ground

Tmin

Daily average minimum air temperature at 2 m above ground

RHum

Daily average relative humidity

HeatIndex

Daily average heat index

Value

A SpatRaster object if as.raster=TRUE, else matrix, list, or data.frame

Additional arguments

interval: supported intervals are “daily”, “pentad”, “dekad”, “monthly”, “2-monthly”, “3-monthly”, and “annual”. Currently hard coded to “daily”.

Examples

library("chirps")
library("terra")

# Case 1: input a data frame return a data frame in the long format
dates <- c("2010-12-15","2010-12-31")
lonlat <- data.frame(lon = c(-55.0281,-54.9857),
                     lat = c(-2.8094, -2.8756))

temp1 <- get_chirts(lonlat, dates, var = "Tmax")

# Case 2: input a data frame return a matrix
temp2 <- get_chirts(lonlat, dates, "Tmax", as.matrix = TRUE)

# Case 3: input a raster and return raster
f <- system.file("ex/lux.shp", package="terra")
v <- vect(f)
temp3 <- get_chirts(v, dates, var = "Tmax", as.raster = TRUE)

# Case 4: input a raster and return raster
temp4 <- get_chirts(v, dates, var = "Tmax", as.matrix = TRUE)

chirps documentation built on Jan. 18, 2022, 1:10 a.m.