BC_27_98.GSB
Derived through NAD83(CSRS)v2. Replaced by NAD27 to NAD83(CSRS) (8) (CT code 9113) for CRD, NAD27 to NAD83(CSRS) (9) (CT code 9114) forn north Vancouver Island and NAD27 to NAD83(CSRS) (10) (CT code 9115) for mainland.
GeoBC, Government of British Columbia, via ISO Geodetic Register.
2019-07-15
metre
EPSG
United States Geological Survey, Western Geographic Science Center
2020-03-26
Statistical analysis.
Uses spherical projection formulas. USGS documentation describes sphere as derived from GRS80/WGS 84 ellipsoid but that actually used is Clarke 1866. For 1:1million and smaller scale maps there is no significant difference.
United States (USA) - onshore and offshore.
Cartesian 2D CS. Axes: easting, northing (X,Y). Orientations: east, north. UoM: m.
Definition: OGC Well Known Text 2 (2019)
BOUNDCRS[ SOURCECRS[ PROJCRS["NAD27 / US National Atlas Equal Area", 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["US National Atlas Equal Area", METHOD["Lambert Azimuthal Equal Area (Spherical)", ID["EPSG",1027]], PARAMETER["Latitude of natural origin",45, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8801]], PARAMETER["Longitude of natural origin",-100, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8802]], PARAMETER["False easting",0, LENGTHUNIT["metre",1], ID["EPSG",8806]], PARAMETER["False northing",0, LENGTHUNIT["metre",1], ID["EPSG",8807]]], CS[Cartesian,2], AXIS["easting (X)",east, ORDER[1], LENGTHUNIT["metre",1]], AXIS["northing (Y)",north, ORDER[2], LENGTHUNIT["metre",1]], USAGE[ SCOPE["Statistical analysis."], AREA["United States (USA) - onshore and offshore."], BBOX[15.56,167.65,74.71,-65.69]], ID["EPSG",9311]]], TARGETCRS[ GEOGCRS["NAD83(CSRS)v2", DATUM["North American Datum of 1983 (CSRS) version 2", 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]], USAGE[ SCOPE["Horizontal component of 3D system."], AREA["Canada - onshore and offshore - Alberta; British Columbia; Manitoba; New Brunswick; Newfoundland and Labrador; Northwest Territories; Nova Scotia; Nunavut; Ontario; Prince Edward Island; Quebec; Saskatchewan; Yukon."], BBOX[38.21,-141.01,86.46,-40.73]], ID["EPSG",8237]]], ABRIDGEDTRANSFORMATION["NAD27 to NAD83(CSRS)v2 (7)", METHOD["NTv2", ID["EPSG",9615]], PARAMETERFILE["Latitude and longitude difference file","BC_27_98.GSB"], USAGE[ SCOPE["Geodesy."], AREA["Canada - British Columbia."], BBOX[48.25,-139.04,60.01,-114.08]], ID["EPSG",9112], REMARK["Derived through NAD83(CSRS)v2. Replaced by NAD27 to NAD83(CSRS) (8) (CT code 9113) for CRD, NAD27 to NAD83(CSRS) (9) (CT code 9114) forn north Vancouver Island and NAD27 to NAD83(CSRS) (10) (CT code 9115) for mainland."]]]
Definition: JSON
{ "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json", "type": "BoundCRS", "source_crs": { "type": "ProjectedCRS", "name": "NAD27 / US National Atlas Equal Area", "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": "US National Atlas Equal Area", "method": { "name": "Lambert Azimuthal Equal Area (Spherical)", "id": { "authority": "EPSG", "code": 1027 } }, "parameters": [ { "name": "Latitude of natural origin", "value": 45, "unit": "degree", "id": { "authority": "EPSG", "code": 8801 } }, { "name": "Longitude of natural origin", "value": -100, "unit": "degree", "id": { "authority": "EPSG", "code": 8802 } }, { "name": "False easting", "value": 0, "unit": "metre", "id": { "authority": "EPSG", "code": 8806 } }, { "name": "False northing", "value": 0, "unit": "metre", "id": { "authority": "EPSG", "code": 8807 } } ] }, "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": 9311 } }, "target_crs": { "type": "GeographicCRS", "name": "NAD83(CSRS)v2", "datum": { "type": "GeodeticReferenceFrame", "name": "North American Datum of 1983 (CSRS) version 2", "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": 8237 } }, "transformation": { "name": "NAD27 to NAD83(CSRS)v2 (7)", "method": { "name": "NTv2", "id": { "authority": "EPSG", "code": 9615 } }, "parameters": [ { "name": "Latitude and longitude difference file", "value": "BC_27_98.GSB", "id": { "authority": "EPSG", "code": 8656 } } ], "id": { "authority": "EPSG", "code": 9112 } } }
Definition: Mapnik
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