ethpgn.las ethpgn.los
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 1734.
US Coast & Geodetic Survey www.ngs.noaa.gov NADCON readme file
2023-01-17
Engineering survey, topographic mapping.
United States (USA) - Alaska - between 160°W and 156°W, onshore.
Cartesian 2D CS. Axes: easting, northing (X,Y). Orientations: east, north. UoM: m.
Definition: OGC Well Known Text 2 (2019)
BOUNDCRS[ SOURCECRS[ PROJCRS["NAD83 / Alaska zone 6", 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["SPCS83 Alaska zone 6 (meter)", METHOD["Transverse Mercator", ID["EPSG",9807]], PARAMETER["Latitude of natural origin",54, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8801]], PARAMETER["Longitude of natural origin",-158, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8802]], PARAMETER["Scale factor at natural origin",0.9999, SCALEUNIT["unity",1], ID["EPSG",8805]], PARAMETER["False easting",500000, 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["Engineering survey, topographic mapping."], AREA["United States (USA) - Alaska - between 160°W and 156°W, onshore."], BBOX[54.89,-160,71.4,-155.99]], ID["EPSG",26936]]], 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) (25)", METHOD["NADCON", ID["EPSG",9613]], PARAMETERFILE["Latitude difference file","ethpgn.las"], PARAMETERFILE["Longitude difference file","ethpgn.los"], USAGE[ SCOPE["Geodesy."], AREA["United States (USA) - Texas east of 100°W."], BBOX[25.83,-100,34.58,-93.5]], ID["EPSG",1498], 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 1734."]]]
Definition: JSON
{ "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json", "type": "BoundCRS", "source_crs": { "type": "ProjectedCRS", "name": "NAD83 / Alaska zone 6", "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": "SPCS83 Alaska zone 6 (meter)", "method": { "name": "Transverse Mercator", "id": { "authority": "EPSG", "code": 9807 } }, "parameters": [ { "name": "Latitude of natural origin", "value": 54, "unit": "degree", "id": { "authority": "EPSG", "code": 8801 } }, { "name": "Longitude of natural origin", "value": -158, "unit": "degree", "id": { "authority": "EPSG", "code": 8802 } }, { "name": "Scale factor at natural origin", "value": 0.9999, "unit": "unity", "id": { "authority": "EPSG", "code": 8805 } }, { "name": "False easting", "value": 500000, "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": 26936 } }, "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) (25)", "method": { "name": "NADCON", "id": { "authority": "EPSG", "code": 9613 } }, "parameters": [ { "name": "Latitude difference file", "value": "ethpgn.las", "id": { "authority": "EPSG", "code": 8657 } }, { "name": "Longitude difference file", "value": "ethpgn.los", "id": { "authority": "EPSG", "code": 8658 } } ], "id": { "authority": "EPSG", "code": 1498 } } }
Definition: Mapnik
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