NA27NA83.GSB
Also distributed with file name QUE27-83.gsb. Replaces NAD27 to NAD83 (5) (code 1462). Uses NT method which expects longitudes positive west; EPSG GeogCRSs NAD27 (code 4267) and NAD83 (code 4269) have longitudes positive east.
Geodetic Service of Quebec.
2019-09-17
Engineering survey, topographic mapping.
Cartesian 2D CS. Axes: easting, northing (X,Y). Orientations: east, north. UoM: ftUS.
Definition: OGC Well Known Text 2 (2019)
BOUNDCRS[ SOURCECRS[ PROJCRS["NAD27 / Alabama West", 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["Alabama CS27 West zone", METHOD["Transverse Mercator", ID["EPSG",9807]], PARAMETER["Latitude of natural origin",30, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8801]], PARAMETER["Longitude of natural origin",-87.5, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8802]], PARAMETER["Scale factor at natural origin",0.999933333, SCALEUNIT["unity",1], ID["EPSG",8805]], PARAMETER["False easting",500000, LENGTHUNIT["US survey foot",0.304800609601219], ID["EPSG",8806]], PARAMETER["False northing",0, LENGTHUNIT["US survey foot",0.304800609601219], ID["EPSG",8807]]], 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]], USAGE[ SCOPE["Engineering survey, topographic mapping."], AREA["United States (USA) - Alabama west of approximately 86°37'W - counties Autauga; Baldwin; Bibb; Blount; Butler; Chilton; Choctaw; Clarke; Colbert; Conecuh; Cullman; Dallas; Escambia; Fayette; Franklin; Greene; Hale; Jefferson; Lamar; Lauderdale; Lawrence; Limestone; Lowndes; Marengo; Marion; Mobile; Monroe; Morgan; Perry; Pickens; Shelby; Sumter; Tuscaloosa; Walker; Washington; Wilcox; Winston."], BBOX[30.14,-88.48,35.02,-86.3]], ID["EPSG",26730]]], 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]], USAGE[ SCOPE["Geodesy."], 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. Puerto Rico. United States (USA) - Alabama; Alaska; Arizona; Arkansas; California; Colorado; Connecticut; Delaware; Florida; Georgia; Hawaii; 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. US Virgin Islands. British Virgin Islands."], BBOX[14.92,167.65,86.45,-40.73]], ID["EPSG",4269]]], ABRIDGEDTRANSFORMATION["NAD27 to NAD83 (6)", METHOD["NTv2", ID["EPSG",9615]], PARAMETERFILE["Latitude and longitude difference file","NA27NA83.GSB"], USAGE[ SCOPE["Transformation of coordinates at 1m to 2m level of accuracy."], AREA["Canada - Quebec."], BBOX[44.99,-79.85,62.62,-57.1]], ID["EPSG",1573], REMARK["Also distributed with file name QUE27-83.gsb. Replaces NAD27 to NAD83 (5) (code 1462). Uses NT method which expects longitudes positive west; EPSG GeogCRSs NAD27 (code 4267) and NAD83 (code 4269) have longitudes positive east."]]]
Definition: JSON
{ "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json", "type": "BoundCRS", "source_crs": { "type": "ProjectedCRS", "name": "NAD27 / Alabama West", "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": "Alabama CS27 West zone", "method": { "name": "Transverse Mercator", "id": { "authority": "EPSG", "code": 9807 } }, "parameters": [ { "name": "Latitude of natural origin", "value": 30, "unit": "degree", "id": { "authority": "EPSG", "code": 8801 } }, { "name": "Longitude of natural origin", "value": -87.5, "unit": "degree", "id": { "authority": "EPSG", "code": 8802 } }, { "name": "Scale factor at natural origin", "value": 0.999933333, "unit": "unity", "id": { "authority": "EPSG", "code": 8805 } }, { "name": "False easting", "value": 500000, "unit": { "type": "LinearUnit", "name": "US survey foot", "conversion_factor": 0.304800609601219 }, "id": { "authority": "EPSG", "code": 8806 } }, { "name": "False northing", "value": 0, "unit": { "type": "LinearUnit", "name": "US survey foot", "conversion_factor": 0.304800609601219 }, "id": { "authority": "EPSG", "code": 8807 } } ] }, "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": 26730 } }, "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 (6)", "method": { "name": "NTv2", "id": { "authority": "EPSG", "code": 9615 } }, "parameters": [ { "name": "Latitude and longitude difference file", "value": "NA27NA83.GSB", "id": { "authority": "EPSG", "code": 8656 } } ], "id": { "authority": "EPSG", "code": 1573 } } }
Definition: Mapnik
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