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Download digital elevation models from Kartverket's WCS API

Source: R/download_dem_kartverket.R
download_dem_kartverket.Rd

Build a WCS URL request with `httr2` to download Kartverket's DEM with `terra::rast()` from a bounding box and a DEM type (i.e. "dom" or "dtm"). The bounding box is centered to a parsed location and a parsed radius set the extent. The downloaded DEM is a SpatRaster object. If the DEM file already exists, it is loaded by default unless f_overwrite is set to TRUE

Usage

download_dem_kartverket(
  stn = NULL,
  name = "dom",
  dx = stn$dx,
  resx = stn$resx,
  path = "data/dem",
  f_overwrite = FALSE
)

Arguments

stn

A SpatVector with station attribute `stationid` from "get_latlon_frost"

name

A name of the DEM to download, either "dtm" a terrain model

dx

A distance in metre or radius defining the extent of the bounding box from the centre point

resx

A horizontal resolution in metre

path

A directory path defining where will be saved the data

f_overwrite

A boolean whether the DEM file should be overwritten

Value

A Digital Elevation Model

References

https://kartkatalog.geonorge.no/metadata/nasjonal-hoeydemodell-digital-terrengmodell-25833-wcs/0f0a0f38-00c4-4213-a9e5-2d861dc4abb0

https://kartkatalog.geonorge.no/metadata/nasjonal-hoeydemodell-digital-overflatemodell-25833-wcs/e36ea427-13a1-4d7c-be82-977068dfc3e3

Examples

# Define parameters
stn <- get_metadata_frost(stationid = 18700, dx = 100, resx = 1)
path   <- "data/dem"

# Load data using httr2 and terra
dem    <- download_dem_kartverket(stn,name="dtm",path=path)
#> [1] "Process: 18700 - 260966.8/6652718.0 - dtm - 100/1 - path: data/dem"
#> [1] "Load demo file: data/dem/18700_dtm_25833_d00100m_1.0m.tif"
dsm    <- download_dem_kartverket(stn,name="dom",path=path)
#> [1] "Process: 18700 - 260966.8/6652718.0 - dom - 100/1 - path: data/dem"
#> [1] "Load demo file: data/dem/18700_dom_25833_d00100m_1.0m.tif"
demkm  <- download_dem_kartverket(stn,name="dtm",dx=20e3,resx=20,path=path)
#> [1] "Process: 18700 - 260966.8/6652718.0 - dtm - 20000/20 - path: data/dem"
#> [1] "Load demo file: data/dem/18700_dtm_25833_d20000m_20.0m.tif"