alhpgn.las alhpgn.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 1717.
US Coast & Geodetic Survey www.ngs.noaa.gov NADCON readme file
2004-04-27
metre
EPSG
Texas Water Development Board, https://www.twdb.texas.gov/
2023-09-28
Mapping and data analysis for Texas Water Development Board groundwater modeling.
Not to be confused with the similar but different TxGIO (TNRIS) CRS, NAD83 / Texas Centric Albers Equal Area (CRS code 3083).
Cartesian 2D CS. Axes: easting, northing (X,Y). Orientations: east, north. UoM: m.
Definition: OGC Well Known Text 2 (2019)
BOUNDCRS[ SOURCECRS[ PROJCRS["NAD83 / TWDB GM", 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["TWDB Groundwater Modeling (US survey foot)", METHOD["Albers Equal Area", ID["EPSG",9822]], PARAMETER["Latitude of false origin",31.25, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8821]], PARAMETER["Longitude of false origin",-100, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8822]], PARAMETER["Latitude of 1st standard parallel",27.5, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8823]], PARAMETER["Latitude of 2nd standard parallel",35, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8824]], PARAMETER["Easting at false origin",4921250, LENGTHUNIT["US survey foot",0.304800609601219], ID["EPSG",8826]], PARAMETER["Northing at false origin",19685000, LENGTHUNIT["US survey foot",0.304800609601219], ID["EPSG",8827]]], CS[Cartesian,2], AXIS["easting (X)",east, ORDER[1], LENGTHUNIT["metre",1]], AXIS["northing (Y)",north, ORDER[2], LENGTHUNIT["metre",1]], USAGE[ SCOPE["Mapping and data analysis for Texas Water Development Board groundwater modeling."], AREA["United States (USA) - Texas."], BBOX[25.83,-106.66,36.5,-93.5]], ID["EPSG",10480]]], 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) (1)", METHOD["NADCON", ID["EPSG",9613]], PARAMETERFILE["Latitude difference file","alhpgn.las"], PARAMETERFILE["Longitude difference file","alhpgn.los"], USAGE[ SCOPE["Geodesy."], AREA["United States (USA) - Alabama."], BBOX[30.14,-88.48,35.02,-84.89]], ID["EPSG",1474], 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 1717."]]]
Definition: JSON
{ "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json", "type": "BoundCRS", "source_crs": { "type": "ProjectedCRS", "name": "NAD83 / TWDB GM", "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": "TWDB Groundwater Modeling (US survey foot)", "method": { "name": "Albers Equal Area", "id": { "authority": "EPSG", "code": 9822 } }, "parameters": [ { "name": "Latitude of false origin", "value": 31.25, "unit": "degree", "id": { "authority": "EPSG", "code": 8821 } }, { "name": "Longitude of false origin", "value": -100, "unit": "degree", "id": { "authority": "EPSG", "code": 8822 } }, { "name": "Latitude of 1st standard parallel", "value": 27.5, "unit": "degree", "id": { "authority": "EPSG", "code": 8823 } }, { "name": "Latitude of 2nd standard parallel", "value": 35, "unit": "degree", "id": { "authority": "EPSG", "code": 8824 } }, { "name": "Easting at false origin", "value": 4921250, "unit": { "type": "LinearUnit", "name": "US survey foot", "conversion_factor": 0.304800609601219 }, "id": { "authority": "EPSG", "code": 8826 } }, { "name": "Northing at false origin", "value": 19685000, "unit": { "type": "LinearUnit", "name": "US survey foot", "conversion_factor": 0.304800609601219 }, "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": 10480 } }, "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) (1)", "method": { "name": "NADCON", "id": { "authority": "EPSG", "code": 9613 } }, "parameters": [ { "name": "Latitude difference file", "value": "alhpgn.las", "id": { "authority": "EPSG", "code": 8657 } }, { "name": "Longitude difference file", "value": "alhpgn.los", "id": { "authority": "EPSG", "code": 8658 } } ], "id": { "authority": "EPSG", "code": 1474 } } }
Definition: Mapnik
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