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Finding Projected Coordinate System

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3 weeks ago
ChelseaLynn
Occasional Contributor

Does anyone know how to find the Projected Coordinate System related to Raster files from the information below?

Projection information                            
-------------------                            
"""+proj=lcc +lat_1=49 +lat_2=77 +lat_0=0 +lon_0=-95 +x_0=0 +y_0=0 +ellps=GRS80 +units=m +no_defs"""                            
-------------------                            
Projection    LAMBERT                            
Spheroid      GRS80                            
Units         METERS                            
Zunits        NO                            
Xshift        0.0                            
Yshift        0.0                            
Parameters                                
  49  0  0.0 /* 1st standard parallel                            
  77  0  0.0 /* 2nd standard parallel                            
 -95  0  0.0 /* central meridian                            
   0  0  0.0 /* latitude of projection's origin                            
0.0 /* false easting (meters)                            
0.0 /* false northing (meters)        

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4 Replies
MichaelPorter2
Occasional Contributor

I guess I don't understand the question. The post gives the projection in a very short form, then again more spelled out.

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AlfredBaldenweck
MVP Regular Contributor

The question is presumably the name or WKID of the projection.

Closest I can find is this:

Projected Coordinate System NAD 1983 CSRS Canada Atlas Lambert
Projection Lambert Conformal Conic
WKID 3979
Linear Unit Meters (1.0)
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 49.0
Authority EPSG
Area of Use Canada
  Top   86.46°
  Left   -141.01°
  Right   -40.73°
  Bottom   38.21°
 
Geographic Coordinate System NAD 1983 (CSRS)
WKID 4617
Previous WKID 4140
Authority EPSG
Angular Unit Degree (0.0174532925199433)
Prime Meridian Greenwich (0.0)
Datum D North American 1983 CSRS
Spheroid GRS 1980
Semimajor Axis 6378137.0
Semiminor Axis 6356752.314140356
Inverse Flattening 298.257222101
Area of Use Canada
Top 86.46°
Left -141.01°
Right -40.73°
Bottom 38.21°

The latitude of origin is wrong, but searching "Lambert" in the Coordinate Systems window in Pro and narrowing it down to likely geographic area got me there

AlfredBaldenweck_0-1765209171352.png

 

RichardDaniels
Honored Contributor

Short answer is this is a standard Lambert Conformal Conic Projection. GRS 1980 is equivalent to WGS84 for most purposes (1 meter accuracy). This projection is centered on Canada at 95 Degrees West Longitude. In this case, values are in Meters. The standard parallels, red dots on the map, define the area of interest.

RichardDaniels_0-1765215097427.png

 

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pokkiri
New Member

Based on the PROJ string parameters you shared, this appears to be a Lambert Conformal Conic projection with standard parallels at 49° and 77°, central meridian at -95°, using GRS80 ellipsoid. This looks like it could be a Canadian projection - possibly Statistics Canada Lambert or a similar national grid.

 

For identifying unknown projections, there's a helpful free tool at https://projectionfinder.comProjection Finder  - you can upload your raster file and it will preview it on a basemap to help verify the CRS visually, and suggest potential EPSG codes based on the coordinate patterns.

 

For your specific case, try searching for "Statistics Canada Lambert" or "NAD83 LCC Canada" in ArcGIS Pro's coordinate system search - the parameters match those commonly used for Canadian national datasets.

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