Method: NADCON
Grid Files: emhpgn.las emhpgn.los
Remarks: Accuracy 67% confidence level. Uses NADCON method which expects longitudes positive west; EPSG GeogCRSs NAD83 (code 4269) and NAD83(HARN) (code 4152) have longitudes positive east. May be taken as approximate transformation NAD83-WGS 84 - see code 1715.
Information source: US Coast & Geodetic Survey www.ngs.noaa.gov NADCON readme file
Revision date: 2004-04-27
Unit: US survey foot
Geodetic CRS: NAD83
Datum: North American Datum 1983
Ellipsoid: GRS 1980
Prime meridian: Greenwich
Data source: EPSG
Information source: OGP
Revision date: 2011-06-30
Scope: No official usage.
Area of use: United States (USA) - between 174°W and 168°W - Alaska and offshore continental shelf (OCS).
Coordinate system: Cartesian 2D CS. Axes: easting, northing (X,Y). Orientations: east, north. UoM: ftUS.
Definition: OGC Well Known Text 2 (2019)
BOUNDCRS[ SOURCECRS[ PROJCRS["NAD83 / BLM 2N (ftUS)", BASEGEOGCRS["NAD83", DATUM["North American Datum 1983", ELLIPSOID["GRS 1980",6378137,298.257222101, LENGTHUNIT["metre",1]]], PRIMEM["Greenwich",0, ANGLEUNIT["degree",0.0174532925199433]], ID["EPSG",4269]], CONVERSION["BLM zone 2N (US survey foot)", METHOD["Transverse Mercator", ID["EPSG",9807]], PARAMETER["Latitude of natural origin",0, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8801]], PARAMETER["Longitude of natural origin",-171, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8802]], PARAMETER["Scale factor at natural origin",0.9996, SCALEUNIT["unity",1], ID["EPSG",8805]], PARAMETER["False easting",1640416.67, 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["No official usage."], AREA["United States (USA) - between 174°W and 168°W - Alaska and offshore continental shelf (OCS)."], BBOX[48.66,-174,73.05,-167.99]], ID["EPSG",4422]]], TARGETCRS[ GEOGCRS["NAD83(HARN)", DATUM["NAD83 (High Accuracy Reference Network)", 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["American Samoa - onshore - Tutuila, Aunu'u, Ofu, Olesega, Ta'u and Rose islands. Guam - onshore. Northern Mariana Islands - onshore. Puerto Rico - onshore. United States (USA) - onshore 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 and Wyoming; offshore Gulf of Mexico continental shelf (GoM OCS). US Virgin Islands - onshore."], BBOX[-14.59,144.58,71.4,-64.51]], ID["EPSG",4152]]], ABRIDGEDTRANSFORMATION["NAD83 to NAD83(HARN) (8)", METHOD["NADCON", ID["EPSG",9613]], PARAMETERFILE["Latitude difference file","emhpgn.las"], PARAMETERFILE["Longitude difference file","emhpgn.los"], USAGE[ SCOPE["Geodesy."], AREA["United States (USA) - Idaho and Montana - east of 113°W."], BBOX[41.99,-113,49.01,-104.04]], ID["EPSG",1481], REMARK["Accuracy 67% confidence level. Uses NADCON method which expects longitudes positive west; EPSG GeogCRSs NAD83 (code 4269) and NAD83(HARN) (code 4152) have longitudes positive east. May be taken as approximate transformation NAD83-WGS 84 - see code 1715."]]]
Definition: JSON
{ "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json", "type": "BoundCRS", "source_crs": { "type": "ProjectedCRS", "name": "NAD83 / BLM 2N (ftUS)", "base_crs": { "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 } }, "conversion": { "name": "BLM zone 2N (US survey foot)", "method": { "name": "Transverse Mercator", "id": { "authority": "EPSG", "code": 9807 } }, "parameters": [ { "name": "Latitude of natural origin", "value": 0, "unit": "degree", "id": { "authority": "EPSG", "code": 8801 } }, { "name": "Longitude of natural origin", "value": -171, "unit": "degree", "id": { "authority": "EPSG", "code": 8802 } }, { "name": "Scale factor at natural origin", "value": 0.9996, "unit": "unity", "id": { "authority": "EPSG", "code": 8805 } }, { "name": "False easting", "value": 1640416.67, "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": 4422 } }, "target_crs": { "type": "GeographicCRS", "name": "NAD83(HARN)", "datum": { "type": "GeodeticReferenceFrame", "name": "NAD83 (High Accuracy Reference Network)", "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": 4152 } }, "transformation": { "name": "NAD83 to NAD83(HARN) (8)", "method": { "name": "NADCON", "id": { "authority": "EPSG", "code": 9613 } }, "parameters": [ { "name": "Latitude difference file", "value": "emhpgn.las", "id": { "authority": "EPSG", "code": 8657 } }, { "name": "Longitude difference file", "value": "emhpgn.los", "id": { "authority": "EPSG", "code": 8658 } } ], "id": { "authority": "EPSG", "code": 1481 } } }
Definition: Mapnik
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