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Several major changes have been made toelevatr in response to theretirement of legacy spatial packages (seehttps://r-spatial.org/r/2023/05/15/evolution4.html for details).Version 0.99.0 has switched to usingsf andterra for all datahandling; however, in this version araster RasterLayer is stillreturned fromget_elev_raster(). Additional changes are planned forversion 1+, most notably the return forget_elev_raster() will be aterra SpatRaster. Please plan accordingly for your analyses and/orpackages account for this change.

An R package for accessing elevation data from various sources

Theelevatr package currently provides access to elevation data fromAWS Open DataTerrainTiles and the OpenTopographyGlobal datasetsAPI for raster digitalelevation models. For point elevation data,theUSGS Elevation PointQuery Service) may be used or thepoint elevations may be derived from the AWS Tiles. Additional elevationdata sources may be added as they come available.

Currently this package includes just two primary functions to accesselevation web services:

• get_elev_point(): Get point elevations using the USGS ElevationPoint Query Service (for the US Only) or using the AWS Terrain Tiles(global). This will accept a data frame of x (long) and y (lat), aSimple Features object, orterra SpatRaster as input. A SimpleFeatures object is returned of the point locations and elevations.
• get_elev_raster(): Get elevation data as a raster (e.g. a DigitalElevation Model) from the AWS Open Data Terrain Tiles or OpenTopography Global datasets. Other sources may be added later. Thiswill accept a data frame of of x (long) and y (lat) or anysf orterra SpatRaster object as input and will return a terraSpatRaster object of the elevation. The extent of the SpatRaster isthe full tiles that cover the bounding box of the input spatial data,but may be clipped to the shape or bounding box of the inputlocations.

Version 0.99.0 of this package is currently available from CRAN and maybe installed by:

install.packages("elevatr")

The development version (this repo) may installed withdevtools:

library(devtools)install_github("usepa/elevatr")

Aselevatr is getting more widely used, there have been some greatcontributions, use cases, and additional packages that have come fromthe user community. If you have one you’d like to share, let me know andI will gladly add it. Here are some of the ones that I have seen. Thankyou all!

• Michaela Mulhearn’srayshader andelevatrcheatsheet
• researchremora on twitter has created some amazing elevation maps
• Hugh Graham’srayvista package usesrayshader,maptiles, andelevatr to create some coolvisualizations
• Spencer Schien has built some fantastic shaded relief visulaizationsand provided the code to recreatethem

Mapzen terrain tiles (which supply the AWS source) contain 3DEP, SRTM,and GMTED2010 content courtesy of the U.S. Geological Survey and ETOPO1content courtesy of U.S. National Oceanic and AtmosphericAdministration. The Open Topography API provide access to the SRTM andthe ALOS World 3D datasets. Seehttps://opentopography.org/ fordetails.

The source code for this repository is maintained athttps://github.com/usepa/elevatr.

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