Reprojecting Spatial Data
Included in this tutorial:
Changing the Coordinate Reference System (aka Re-projecting) a vector layer with the Project tool
Changing the Coordinate Reference System (aka Re-projecting) a raster layer with the Project Raster tool
Software version in examples: ArcGIS Pro 2.8.0.
Tutorial Data: The tutorial includes demonstration with a vector layer from Natural Earth and a raster layer from the Landsat8 OLI, available from the USGS EarthExplorer.
Natural Earth. “Admin 0 - Countries.” [shapefile]. 1:50m Cultural Vectors, version 4.1.0. 25 May 2018. Accessed 28 June 2021 from https://www.naturalearthdata.com/downloads/50m-cultural-vectors/
US Geological Survey. “Scene LC80250392017080LGN00” [geoTIFF]. Landsat 8 OLI/TIRS, collection 1, level 1. 21 March 2017. Accessed 11 July 2021 from https://earthexplorer.usgs.gov/
Credits: L. Meisterlin with Erik Strand, Moses Levich, and Thiago Lee (2021)
This tutorial demonstrates re-projecting a vector and a raster layer. In both cases, a new dataset is created with the assigned coordinate system. The original data layer is changed.
Changing the Coordinate Reference System of a Vector Layer: the Project tool
To reproject a vector feature layer, access the Project tool in ArcPro’s Geoprocessing Pane. You can use the search function or navigate through the Toolboxes (tab by clicking through Data Management Tools > Projections and Transformations > Project.
The demonstration below reprojects the “Admin 0 - Countries” dataset into the Winkel Tripel CRS.
Within the Project tool dialogue,
Choose an input layer to reproject, in our demonstration, this is the Countries shapefile.
Name the output file, and specify the location to save it.
Choose the output CRS. (In our demo: Winkel Tripel.)
reprojecting a feature class with the Project tool
TIPS: In the Coordinate Systems dialogue (accessed when you browse or search for a specific CRS), right-click on a CRS and select Add to Favorites to make a common CRS easier to find. The folder-browsing menu also includes a folder with the CRS information for each layer in the current ArcGIS Pro project (to choose the same CRS as another layer quickly).
Changing the Coordinate Reference System of a Raster Layer: the Project Raster tool
To reproject a raster layer, access the Project Raster tool in the Geoprocessing Pane by using the search function or by navigating under the Toolboxes (tab) by clicking through Data Management Tools > Projections and Transformations > Raster > Project Raster.
This example demonstrates reprojecting Band 1 of the Landsat dataset covering Houston, Texas.
The Project Raster dialogue box will appear within the Geoprocessing Pane, with several parameters:
Choose the input raster (here, the Landsat layer).
Choose the new output CRS for the raster. This demo will use Texas State Plane Zone 4 [FIPS 4204], in meters. Navigate the folders or use the search bar to find the desired CRS.
Choose the output raster cell size, if applicable. For this example, it is not necessary to specify a new cell size. The cell size of the input raster (30m) will be preserved.
Choose the raster resampling method. In this case, we use Nearest Neighbor, as the values in this raster do not represent continuous data.
Specify the output location and file name of your new raster. Specify a file type by entering the file extension (.tif, for this example) after the chosen file name.
Note that for large datasets, the Project Raster tool may take some time to run.
EXTRA: More on the Project Raster tool including output file types and resampling methods can be found from Esri here.
reprojecting a raster with the Project Raster tool