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I have a polygon shapefile and a raster. The shapefile and raster have different coordinate systems.

Coordinate System for the shapefile:

NAD_1983_UTM_Zone_19N
WKID: 26919 Authority: EPSG

Projection: Transverse_Mercator
False_Easting: 500000.0
False_Northing: 0.0
Central_Meridian: -69.0
Scale_Factor: 0.9996
Latitude_Of_Origin: 0.0
Linear Unit: Meter (1.0)

Geographic Coordinate System: GCS_North_American_1983
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

Coordinate System for the raster:

LCC_E008
Authority: Custom

Projection: Lambert_Conformal_Conic
false_easting: 0.0
false_northing: 0.0
central_meridian: -95.0
standard_parallel_1: 49.0
standard_parallel_2: 77.0
latitude_of_origin: 0.0
Linear Unit: Meter (1.0)

Geographic Coordinate System: GCS_Unknown_datum_based_upon_the_GRS_1980_ellipsoid
Angular Unit: Degree (0.0174532925199433)
Prime Meridian: Greenwich (0.0)
Datum: D_GRS_1980
  Spheroid: GRS_1980
    Semimajor Axis: 6378137.0
    Semiminor Axis: 6356752.314140356
    Inverse Flattening: 298.257222101

I would like to transform the shapefile's coordinate system in order that the shapefile and raster have the same coordinate systems.

I tried to use the function Project in ArcGIS 10.1 by specifying:

  • LCC_E008 (in folder "Layers") as output coordinate system
  • NAD_1983_To_WGS_1984_1 as Geographic transformation (this optional parameter was required in my case)

But I obtained this error message:

000151 : The geotransformation(s) is not valid.

How can I to change the coordinate system for my shapefile ?

2 Answers 2

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It looks to me like the Lambert projection file has an error. GRS_1980 is a spheroid, not a datum. The NAD83 datum is based on the GRS_1980 spheroid. I think it is possible that your Lambert projection is actually using the NAD83 datum.

Your datum transformation throws an error because you are not trying to transform between WGS_1984 and NAD83.

If it were me, I would try correcting the raster's Lambert projection file so it reads Datum: D_North_American_1983 instead of Datum: D_GRS_1980. (Keep a backup, of course.)

Then try to project the shapefile to the raster's Lambert projection again. This should work.

To correct the projection, I think you can just use the define projection tool (System Toolboxes > Data Management Tools > Projections and Transformations > Define Projection). Just pick the correct Lambert State Plane projection.

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  • Even if NAD83 (CSRS) was used as the datum, the datum is still written incorrectly in the projection file. I have worked in Canada, and I have ran into this problem that mkennedy speaks of, i.e., ESRI GRIDs don't support NAD83 (CSRS). To be honest, if I absolutely had to work with other data sets in plain old NAD83, I just pretended. That is, I redefined the projection as NAD83. I never had any problems, since my data was not as accurate as the difference between the two datums anyway. I noticed that many people in Canda don't use NAD83 (CSRS) for this reason.
    – RHB
    Commented Jan 27, 2016 at 20:00
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Is the raster format an Esri GRID? If so, the original LCC definition may have used NAD83 (CSRS) which isn't supported in the PRJ.ADF file format used by Esri grids.

The definition doesn't match any of the existing Canadian LCC definitions, but it's close.

Do try to change the geographic coordinate reference system only to NAD 1983 (North American 1983) using the raster's property page or the Define Projection tool. At that point you could be able to project one of the datasets to the other's coordinate reference system.

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