NTv1_0.gsb
Approximation at the +/- 1m level assuming that NAD83 is equivalent to WGS 84. Superseded by NAD27 to WGS 84 (27) (code 8404) in Quebec and NAD27 to WGS 84 (26) (code 8245) elsewhere in Canada.
OGP
1998-11-11
Data analysis and small scale data presentation for contiguous lower 48 states.
Replaced by NAD83 / Conus Albers (CRS code 5070).
Cartesian 2D CS. Axes: easting, northing (X,Y). Orientations: east, north. UoM: m.
304536.7 4292928.12
-3202494.08 3680366.54
-1915705.35 6190502.67
-141.01 38.21
-40.73 86.46
Definition: OGC Well Known Text 2 (2019)
BOUNDCRS[ SOURCECRS[ BOUNDCRS[ SOURCECRS[ PROJCRS["NAD27 / Conus 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["Conus Albers", METHOD["Albers Equal Area", ID["EPSG",9822]], PARAMETER["Latitude of false origin",23, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8821]], PARAMETER["Longitude of false origin",-96, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8822]], PARAMETER["Latitude of 1st standard parallel",29.5, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8823]], PARAMETER["Latitude of 2nd standard parallel",45.5, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8824]], PARAMETER["Easting at false origin",0, LENGTHUNIT["metre",1], ID["EPSG",8826]], PARAMETER["Northing at false origin",0, LENGTHUNIT["metre",1], ID["EPSG",8827]]], CS[Cartesian,2], AXIS["easting (X)",east, ORDER[1], LENGTHUNIT["metre",1]], AXIS["northing (Y)",north, ORDER[2], LENGTHUNIT["metre",1]], ID["EPSG",5069]]], 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]]], ABRIDGEDTRANSFORMATION["NAD27 to NAD83 (3)", METHOD["NTv1", ID["EPSG",9614]], PARAMETERFILE["Latitude and longitude difference file","NTv1_0.gsb"], ID["EPSG",1312]]]], 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)"], 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 (1)", METHOD["Geocentric translations (geog2D domain)", ID["EPSG",9603]], PARAMETER["X-axis translation",0, ID["EPSG",8605]], PARAMETER["Y-axis translation",0, ID["EPSG",8606]], PARAMETER["Z-axis translation",0, ID["EPSG",8607]], USAGE[ SCOPE["Military survey."], AREA["North America - onshore and offshore: Canada - Alberta; British Columbia; Manitoba; New Brunswick; Newfoundland and Labrador; Northwest Territories; Nova Scotia; Nunavut; Ontario; Prince Edward Island; Quebec; Saskatchewan; Yukon. United States (USA) - Alabama; Alaska (mainland); Arizona; Arkansas; California; Colorado; Connecticut; Delaware; Florida; Georgia; Idaho; Illinois; Indiana; Iowa; Kansas; Kentucky; Louisiana; Maine; Maryland; Massachusetts; Michigan; Minnesota; Mississippi; Missouri; Montana; Nebraska; Nevada; New Hampshire; New Jersey; New Mexico; New York; North Carolina; North Dakota; Ohio; Oklahoma; Oregon; Pennsylvania; Rhode Island; South Carolina; South Dakota; Tennessee; Texas; Utah; Vermont; Virginia; Washington; West Virginia; Wisconsin; Wyoming."], BBOX[23.81,-172.54,86.46,-47.74]], ID["EPSG",1188], REMARK["Derived at 354 stations. Accuracy 2m in each axis."]]]
Definition: JSON
{ "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json", "type": "BoundCRS", "source_crs": { "type": "BoundCRS", "source_crs": { "type": "ProjectedCRS", "name": "NAD27 / Conus Albers", "base_crs": { "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 } }, "conversion": { "name": "Conus Albers", "method": { "name": "Albers Equal Area", "id": { "authority": "EPSG", "code": 9822 } }, "parameters": [ { "name": "Latitude of false origin", "value": 23, "unit": "degree", "id": { "authority": "EPSG", "code": 8821 } }, { "name": "Longitude of false origin", "value": -96, "unit": "degree", "id": { "authority": "EPSG", "code": 8822 } }, { "name": "Latitude of 1st standard parallel", "value": 29.5, "unit": "degree", "id": { "authority": "EPSG", "code": 8823 } }, { "name": "Latitude of 2nd standard parallel", "value": 45.5, "unit": "degree", "id": { "authority": "EPSG", "code": 8824 } }, { "name": "Easting at false origin", "value": 0, "unit": "metre", "id": { "authority": "EPSG", "code": 8826 } }, { "name": "Northing at false origin", "value": 0, "unit": "metre", "id": { "authority": "EPSG", "code": 8827 } } ] }, "coordinate_system": { "subtype": "Cartesian", "axis": [ { "name": "Easting", "abbreviation": "X", "direction": "east", "unit": "metre" }, { "name": "Northing", "abbreviation": "Y", "direction": "north", "unit": "metre" } ] }, "id": { "authority": "EPSG", "code": 5069 } }, "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 } }, "transformation": { "name": "NAD27 to NAD83 (3)", "method": { "name": "NTv1", "id": { "authority": "EPSG", "code": 9614 } }, "parameters": [ { "name": "Latitude and longitude difference file", "value": "NTv1_0.gsb", "id": { "authority": "EPSG", "code": 8656 } } ], "id": { "authority": "EPSG", "code": 1312 } } }, "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 } } ], "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 (1)", "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 } }, "method": { "name": "Geocentric translations (geog2D domain)", "id": { "authority": "EPSG", "code": 9603 } }, "parameters": [ { "name": "X-axis translation", "value": 0, "unit": "metre", "id": { "authority": "EPSG", "code": 8605 } }, { "name": "Y-axis translation", "value": 0, "unit": "metre", "id": { "authority": "EPSG", "code": 8606 } }, { "name": "Z-axis translation", "value": 0, "unit": "metre", "id": { "authority": "EPSG", "code": 8607 } } ], "id": { "authority": "EPSG", "code": 1188 } } }
Definition: Mapnik
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