Name: NAD27 to WGS 84 (75)
Grid Files: conus.las conus.los wvhpgn.las wvhpgn.los
Remarks: Transformation steps are from NAD27 to NAD83(HARN) (35) (code 8514) assuming that NAD83(HARN) is equivalent to WGS 84 within the accuracy of the transformation.
Information source: OGP
Revision date: 2020-03-14
Unit: US survey foot
Geodetic CRS: NAD27
Datum: North American Datum 1927
Ellipsoid: Clarke 1866
Prime meridian: Greenwich
Data source: EPSG
Information source: Various industry sources.
Revision date: 2002-09-19
Scope: Topographic mapping (small scale).
Area of use: United States (USA) - Alaska.
Coordinate system: Cartesian 2D CS. Axes: easting, northing (X,Y). Orientations: east, north. UoM: ftUS.
Definition: OGC Well Known Text 2 (2019)
BOUNDCRS[ SOURCECRS[ BOUNDCRS[ SOURCECRS[ PROJCRS["NAD27 / Alaska Albers", BASEGEOGCRS["NAD27", DATUM["North American Datum 1927", ELLIPSOID["Clarke 1866",6378206.4,294.978698213898, LENGTHUNIT["metre",1]]], PRIMEM["Greenwich",0, ANGLEUNIT["degree",0.0174532925199433]], ID["EPSG",4267]], CONVERSION["Alaska Albers", METHOD["Albers Equal Area", ID["EPSG",9822]], PARAMETER["Latitude of false origin",50, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8821]], PARAMETER["Longitude of false origin",-154, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8822]], PARAMETER["Latitude of 1st standard parallel",55, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8823]], PARAMETER["Latitude of 2nd standard parallel",65, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8824]], PARAMETER["Easting at false origin",0, LENGTHUNIT["US survey foot",0.304800609601219], ID["EPSG",8826]], PARAMETER["Northing at false origin",0, LENGTHUNIT["US survey foot",0.304800609601219], ID["EPSG",8827]]], CS[Cartesian,2], AXIS["easting (X)",east, ORDER[1], LENGTHUNIT["US survey foot",0.304800609601219]], AXIS["northing (Y)",north, ORDER[2], LENGTHUNIT["US survey foot",0.304800609601219]], ID["EPSG",2964]]], TARGETCRS[ GEOGCRS["NAD83", DATUM["North American Datum 1983", ELLIPSOID["GRS 1980",6378137,298.257222101, LENGTHUNIT["metre",1]]], PRIMEM["Greenwich",0, ANGLEUNIT["degree",0.0174532925199433]], CS[ellipsoidal,2], AXIS["geodetic latitude (Lat)",north, ORDER[1], ANGLEUNIT["degree",0.0174532925199433]], AXIS["geodetic longitude (Lon)",east, ORDER[2], ANGLEUNIT["degree",0.0174532925199433]], ID["EPSG",4269], REMARK["Longitude is POSITIVE EAST. The adjustment included connections to Greenland and Mexico but the system was not adopted there. For applications with an accuracy of better than 1m replaced by NAD83(HARN) in the US and PRVI and by NAD83(CSRS) in Canada."]]], ABRIDGEDTRANSFORMATION["NAD27 to NAD83 (1)", METHOD["NADCON", ID["EPSG",9613]], PARAMETERFILE["Latitude difference file","conus.las"], PARAMETERFILE["Longitude difference file","conus.los"], ID["EPSG",1241]]]], TARGETCRS[ GEOGCRS["WGS 84", ENSEMBLE["World Geodetic System 1984 ensemble", MEMBER["World Geodetic System 1984 (Transit)"], MEMBER["World Geodetic System 1984 (G730)"], MEMBER["World Geodetic System 1984 (G873)"], MEMBER["World Geodetic System 1984 (G1150)"], MEMBER["World Geodetic System 1984 (G1674)"], MEMBER["World Geodetic System 1984 (G1762)"], MEMBER["World Geodetic System 1984 (G2139)"], MEMBER["World Geodetic System 1984 (G2296)"], ELLIPSOID["WGS 84",6378137,298.257223563, LENGTHUNIT["metre",1]], ENSEMBLEACCURACY[2.0]], PRIMEM["Greenwich",0, ANGLEUNIT["degree",0.0174532925199433]], CS[ellipsoidal,2], AXIS["geodetic latitude (Lat)",north, ORDER[1], ANGLEUNIT["degree",0.0174532925199433]], AXIS["geodetic longitude (Lon)",east, ORDER[2], ANGLEUNIT["degree",0.0174532925199433]], USAGE[ SCOPE["Horizontal component of 3D system."], AREA["World."], BBOX[-90,-180,90,180]], ID["EPSG",4326]]], ABRIDGEDTRANSFORMATION["NAD83 to WGS 84 (51)", METHOD["NADCON", ID["EPSG",9613]], PARAMETERFILE["Latitude difference file","wvhpgn.las"], PARAMETERFILE["Longitude difference file","wvhpgn.los"], USAGE[ SCOPE["(null/copy) Approximation for medium and low accuracy applications assuming equality between plate-fixed static and earth-fixed dynamic CRSs, ignoring static/dynamic CRS differences."], AREA["United States (USA) - West Virginia."], BBOX[37.2,-82.65,40.64,-77.72]], ID["EPSG",1747], REMARK["Parameter files are from NAD83 to NAD83(HARN) (37) (code 1526) assuming that NAD83(HARN) is equivalent to WGS 84 within the accuracy of the transformation."]]]
Definition: JSON
{ "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json", "type": "BoundCRS", "source_crs": { "type": "BoundCRS", "source_crs": { "type": "ProjectedCRS", "name": "NAD27 / Alaska Albers", "base_crs": { "type": "GeographicCRS", "name": "NAD27", "datum": { "type": "GeodeticReferenceFrame", "name": "North American Datum 1927", "ellipsoid": { "name": "Clarke 1866", "semi_major_axis": 6378206.4, "semi_minor_axis": 6356583.8 } }, "coordinate_system": { "subtype": "ellipsoidal", "axis": [ { "name": "Geodetic latitude", "abbreviation": "Lat", "direction": "north", "unit": "degree" }, { "name": "Geodetic longitude", "abbreviation": "Lon", "direction": "east", "unit": "degree" } ] }, "id": { "authority": "EPSG", "code": 4267 }, "remarks": "Note: this CRS includes longitudes which are POSITIVE EAST. Replaced by NAD27(76) (code 4608) in Ontario, CGQ77 (code 4609) in Quebec, Mexican Datum of 1993 (code 4483) in Mexico, NAD83 (code 4269) in Canada (excl. Ontario & Quebec) & USA." }, "conversion": { "name": "Alaska Albers", "method": { "name": "Albers Equal Area", "id": { "authority": "EPSG", "code": 9822 } }, "parameters": [ { "name": "Latitude of false origin", "value": 50, "unit": "degree", "id": { "authority": "EPSG", "code": 8821 } }, { "name": "Longitude of false origin", "value": -154, "unit": "degree", "id": { "authority": "EPSG", "code": 8822 } }, { "name": "Latitude of 1st standard parallel", "value": 55, "unit": "degree", "id": { "authority": "EPSG", "code": 8823 } }, { "name": "Latitude of 2nd standard parallel", "value": 65, "unit": "degree", "id": { "authority": "EPSG", "code": 8824 } }, { "name": "Easting at false origin", "value": 0, "unit": { "type": "LinearUnit", "name": "US survey foot", "conversion_factor": 0.304800609601219 }, "id": { "authority": "EPSG", "code": 8826 } }, { "name": "Northing at false origin", "value": 0, "unit": { "type": "LinearUnit", "name": "US survey foot", "conversion_factor": 0.304800609601219 }, "id": { "authority": "EPSG", "code": 8827 } } ] }, "coordinate_system": { "subtype": "Cartesian", "axis": [ { "name": "Easting", "abbreviation": "X", "direction": "east", "unit": { "type": "LinearUnit", "name": "US survey foot", "conversion_factor": 0.304800609601219 } }, { "name": "Northing", "abbreviation": "Y", "direction": "north", "unit": { "type": "LinearUnit", "name": "US survey foot", "conversion_factor": 0.304800609601219 } } ] }, "id": { "authority": "EPSG", "code": 2964 } }, "target_crs": { "type": "GeographicCRS", "name": "NAD83", "datum": { "type": "GeodeticReferenceFrame", "name": "North American Datum 1983", "ellipsoid": { "name": "GRS 1980", "semi_major_axis": 6378137, "inverse_flattening": 298.257222101 } }, "coordinate_system": { "subtype": "ellipsoidal", "axis": [ { "name": "Geodetic latitude", "abbreviation": "Lat", "direction": "north", "unit": "degree" }, { "name": "Geodetic longitude", "abbreviation": "Lon", "direction": "east", "unit": "degree" } ] }, "id": { "authority": "EPSG", "code": 4269 }, "remarks": "Longitude is POSITIVE EAST. The adjustment included connections to Greenland and Mexico but the system was not adopted there. For applications with an accuracy of better than 1m replaced by NAD83(HARN) in the US and PRVI and by NAD83(CSRS) in Canada." }, "transformation": { "name": "NAD27 to NAD83 (1)", "method": { "name": "NADCON", "id": { "authority": "EPSG", "code": 9613 } }, "parameters": [ { "name": "Latitude difference file", "value": "conus.las", "id": { "authority": "EPSG", "code": 8657 } }, { "name": "Longitude difference file", "value": "conus.los", "id": { "authority": "EPSG", "code": 8658 } } ], "id": { "authority": "EPSG", "code": 1241 } } }, "target_crs": { "type": "GeographicCRS", "name": "WGS 84", "datum_ensemble": { "name": "World Geodetic System 1984 ensemble", "members": [ { "name": "World Geodetic System 1984 (Transit)", "id": { "authority": "EPSG", "code": 1166 } }, { "name": "World Geodetic System 1984 (G730)", "id": { "authority": "EPSG", "code": 1152 } }, { "name": "World Geodetic System 1984 (G873)", "id": { "authority": "EPSG", "code": 1153 } }, { "name": "World Geodetic System 1984 (G1150)", "id": { "authority": "EPSG", "code": 1154 } }, { "name": "World Geodetic System 1984 (G1674)", "id": { "authority": "EPSG", "code": 1155 } }, { "name": "World Geodetic System 1984 (G1762)", "id": { "authority": "EPSG", "code": 1156 } }, { "name": "World Geodetic System 1984 (G2139)", "id": { "authority": "EPSG", "code": 1309 } }, { "name": "World Geodetic System 1984 (G2296)", "id": { "authority": "EPSG", "code": 1383 } } ], "ellipsoid": { "name": "WGS 84", "semi_major_axis": 6378137, "inverse_flattening": 298.257223563 }, "accuracy": "2.0", "id": { "authority": "EPSG", "code": 6326 } }, "coordinate_system": { "subtype": "ellipsoidal", "axis": [ { "name": "Geodetic latitude", "abbreviation": "Lat", "direction": "north", "unit": "degree" }, { "name": "Geodetic longitude", "abbreviation": "Lon", "direction": "east", "unit": "degree" } ] }, "id": { "authority": "EPSG", "code": 4326 } }, "transformation": { "name": "NAD83 to WGS 84 (51)", "source_crs": { "type": "GeographicCRS", "name": "NAD83", "datum": { "type": "GeodeticReferenceFrame", "name": "North American Datum 1983", "ellipsoid": { "name": "GRS 1980", "semi_major_axis": 6378137, "inverse_flattening": 298.257222101 } }, "coordinate_system": { "subtype": "ellipsoidal", "axis": [ { "name": "Geodetic latitude", "abbreviation": "Lat", "direction": "north", "unit": "degree" }, { "name": "Geodetic longitude", "abbreviation": "Lon", "direction": "east", "unit": "degree" } ] }, "id": { "authority": "EPSG", "code": 4269 }, "remarks": "Longitude is POSITIVE EAST. The adjustment included connections to Greenland and Mexico but the system was not adopted there. For applications with an accuracy of better than 1m replaced by NAD83(HARN) in the US and PRVI and by NAD83(CSRS) in Canada." }, "method": { "name": "NADCON", "id": { "authority": "EPSG", "code": 9613 } }, "parameters": [ { "name": "Latitude difference file", "value": "wvhpgn.las", "id": { "authority": "EPSG", "code": 8657 } }, { "name": "Longitude difference file", "value": "wvhpgn.los", "id": { "authority": "EPSG", "code": 8658 } } ], "id": { "authority": "EPSG", "code": 1747 } } }
Definition: Mapnik
<?xml version="1.0" encoding="utf-8"?> <Map srs="+proj=aea +lat_0=50 +lon_0=-154 +lat_1=55 +lat_2=65 +x_0=0 +y_0=0 +ellps=clrk66 +nadgrids=us_noaa_wvhpgn.tif +units=us-ft +no_defs +type=crs"> <Layer srs="+proj=aea +lat_0=50 +lon_0=-154 +lat_1=55 +lat_2=65 +x_0=0 +y_0=0 +ellps=clrk66 +nadgrids=us_noaa_wvhpgn.tif +units=us-ft +no_defs +type=crs"> </Layer> </Map>