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I have a very large raster layer (67g uncompressed) that was merged from multiple tif files in ArcGIS Pro. However, I have not been able to get it in the correct location (USA) and it is displaying over Africa.

  1. I first merged the original tif files using the 'Mosaic to New Raster Tool' For these settings, I ensured that the 'Spatial Reference for Raster' matched (NAD_1983_Albers), 'Pixel Type' (16 bit unsigned), 'Cell Size' (30), 'Number of Bands' (1), 'Mosaic Operator' (Last), 'Mosaic Colormap Mode' (First).

  2. Since this did not work, I tried merging the original files again with the 'Mosaic to New Raster Tool' using 'WGS_1984_Web_Mercator_Auxiliary_Sphere' for my 'Spatial Reference for Raster'. No luck.

I then used a few different tools applied to the raster layer or map layer instead but I haven't had any luck. What I have attempted thus far:

  1. 'Define Projection Tool' to match the raster layer (NAD_1983_Albers) to the base map layer ('WGS_1984_Web_Mercator_Auxiliary_Sphere').

  2. 'Project Raster Tool' to match the raster layer (NAD_1983_Albers) to the base map layer. 'Output Coordinate System' set as 'WGS_1984_Web_Mercator_Auxiliary_Sphere', 'Geographic Transformation' set as 'NAD_1983_To_WGS_1984_5', 'Resampling Technique' set as 'Nearest neighbor', 'Output Cell Size' set as the merged raster layer, 'X and Y' as 30.

  3. I then tried transforming the base map layer's Coordinate System by right clicking the map layer > Properties > Coordinate Systems to see if the base map would align with the raster layer. I tried Geographic Coordinate Systems (a) changing to 'NAD 1983 Albers', (b) changing to 'NAD 1983', (c) changing to 'NAD 1983 (2011); I tried Projected Coordinate Systems (d) changing to 'NAD 1983 (2011) Contiguous USA Albers', (e) changing to 'NAD 1983 Contiguous USA Albers'.

  4. I then tried to manually enter the Coordinate system by hitting Properties > Coordinate Systems > Add Coordinate System > New Geographic Coordinate System and inputing the information embedded in the raster data.

  5. I then tried to manually enter the Coordinate system by hitting Properties > Coordinate Systems > Add Coordinate System > New Projected Coordinate System and inputing the information embedded in the raster data.

The information for the raster layer provided by the author of the layer:

Projection type: Projection transform: List (6 elements) wkt:
PROJCS["NAD_1983_Albers",
GEOGCS["NAD83",
DATUM["North_American_Datum_1983",
SPHEROID["GRS 1980", 6378137.0, 298.2572221010042,
AUTHORITY["EPSG","7019"]],
AUTHORITY["EPSG","6269"]],
PRIMEM["Greenwich", 0.0],
UNIT["degree", 0.017453292519943295],
AXIS["Longitude", EAST],
AXIS["Latitude", NORTH],
AUTHORITY["EPSG","4269"]],
PROJECTION["Albers_Conic_Equal_Area"],
PARAMETER["central_meridian", -96.0],
PARAMETER["latitude_of_origin", 37.5],
PARAMETER["standard_parallel_1", 29.5],
PARAMETER["false_easting", 0.0],
PARAMETER["false_northing", 0.0],
PARAMETER["standard_parallel_2", 45.5],
UNIT["m", 1.0],
AXIS["x", EAST],
AXIS["y", NORTH]]

The Spatial Reference information for my merged raster layer from ArcGIS is as follows:

Projected Coordinate System: NAD 1983 Albers,
Projection: Albers,
WKID: 0,
Authority:,
Linear Unit: Meter (1.0),
false easting: 0.0,
false northing: 0.0,
central meridian: 0.0,
standard parallel 1: 29.5,
standard parallel 2: 45.5,
latitude of origin: 0.0,
Geographic coordinate system: GCS North American 1983,
Authority: EPSG,
Angular unit: Degree (0.0174532925199433),
Prime Meridian: Greenwich (0.0),
Datum: D North American 1983,
Spheroid: GRS 1980,
Semimajor Axis: 6378137.0,
Semiminor Axis: 6356752.314140356,
Inverse Flattening: 298.257222101,

As you can see, the only differences in Spatial Reference information is the 'Central Meridian' and 'Latitude of Origin'. I have attempted to move the base map layer to match these values in the Properties > Coordinate Systems > Add Coordinate System > New Projected Coordinate System but that did not work. I have tried to find resources online on how to change the 'Central Meridian' or 'Latitude of Origin' of a raster layer specifically but haven't had any luck. I am at my wits end trying to solve what seems to be a very simple fix. This roadblock is stalling progression for a dissertation chapter.

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  • Why do you want one raster, can you use a Mosaic dataset instead? Large rasters are difficult to work with. Do the individual rasters you start with display at the correct location?
    – Bera
    Commented Sep 20, 2022 at 16:19
  • Hello—unfortunately, the individual rasters display in the wrong location as well. I'm unsure of the pros and cons of working with a mosaic dataset instead of one single raster. It seemed straightforward in my mind to use one layer so that I may overlay with a separate shapefile layer to conduct an analysis.
    – zespino1
    Commented Sep 20, 2022 at 16:28
  • 1
    Sounds like they have an incorrectly defined coordinate system. You need to find out which coordinate system it should be, and define it. Whoever created them should know
    – Bera
    Commented Sep 20, 2022 at 16:52

1 Answer 1

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  1. By switching to ArcMap I was able to see Spatial Reference details pertaining to each specific Projected Coordinate System. (I was blindly choosing random ones prior; at least six different tries based on best guesses)

  2. I was able to find the correct coordinate system matching the information for the raster layer (provided by the author of the layer). It was USA Contiguous Albers Equal Area Conic. This finally matched the Central Meridian, Latitude of Origin, Standard Parallel 1, Standard Parallel 2.

  3. In ArcGIS Pro I used the 'Define Projection Tool' and selected USA Contiguous Albers Equal Area Conic, to change it from NAD 1983 Albers.

This fixed my problem and the raster layer was displaying in the correct location.

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