drought_indicator function

Calculate drought indicator statistics

This function allows to efficiently calculate the relative wetness in the shallow groundwater section with regard to the the 1948-2012 reference period. The values represent the wetness percentile a given area achieves at a given point in time in regard to the reference period. For each polygon, the desired statistic/s (mean, median or sd) is/are returned.

calc_drought_indicator(engine = "extract", stats = "mean")

Arguments

• engine: The preferred processing functions from either one of "zonal", "extract" or "exactextract" as character.
• stats: Function to be applied to compute statistics for polygons either one or multiple inputs as character "mean", "median" or "sd".

Returns

A function that returns an indicator tibble with specified drought indicator statistics as variable and corresponding values as value.

Details

The required resources for this indicator are:

• nasa_grace

Examples

## Not run:

library(sf)
library(mapme.biodiversity)

outdir <- file.path(tempdir(), "mapme-data")
dir.create(outdir, showWarnings = FALSE)

mapme_options(
  outdir = outdir,
  verbose = FALSE
)

aoi <- system.file("extdata", "sierra_de_neiba_478140_2.gpkg",
  package = "mapme.biodiversity"
) %>%
  read_sf() %>%
  get_resources(get_nasa_grace(years = 2022)) %>%
  calc_indicators(
    calc_drought_indicator(
      engine = "extract",
      stats = c("mean", "median")
    )
  ) %>%
  portfolio_long()

aoi
## End(Not run)