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Name: NAD83 to WGS 84 (21)
Method: NADCON
Grid Files: alhpgn.las alhpgn.los
Remarks: Parameter files are from NAD83 to NAD83(HARN) (1) (code 1474) assuming that NAD83(HARN) is equivalent to WGS 84 within the accuracy of the transformation.
Information source: OGP
Revision date: 2021-09-10
Unit: US survey foot
Geodetic CRS: NAD83
Datum: North American Datum 1983
Ellipsoid: GRS 1980
Prime meridian: Greenwich
Data source: EPSG
Information source: Texas Water Development Board, https://www.twdb.texas.gov/
Revision date: 2023-09-30
Scope: Mapping and data analysis for Texas Water Development Board groundwater modeling.
Remarks: Not to be confused with the similar but different TxGIO (TNRIS) CRS, NAD83 / Texas Centric Albers Equal Area (CRS code 3083).
Area of use: United States (USA) - Texas.
Coordinate system: Cartesian 2D CS. Axes: easting, northing (X,Y). Orientations: east, north. UoM: ftUS.
Definition: OGC Well Known Text
PROJCS["NAD83 / TWDB GM", GEOGCS["NAD83", DATUM["North_American_Datum_1983", SPHEROID["GRS 1980",6378137,298.257222101], EXTENSION["PROJ4_GRIDS","us_noaa_alhpgn.tif"]], PRIMEM["Greenwich",0, AUTHORITY["EPSG","8901"]], UNIT["degree",0.0174532925199433, AUTHORITY["EPSG","9122"]], AUTHORITY["EPSG","4269"]], PROJECTION["Albers_Conic_Equal_Area"], PARAMETER["latitude_of_center",31.25], PARAMETER["longitude_of_center",-100], PARAMETER["standard_parallel_1",27.5], PARAMETER["standard_parallel_2",35], PARAMETER["false_easting",4921250], PARAMETER["false_northing",19685000], UNIT["US survey foot",0.304800609601219], AXIS["Easting",EAST], AXIS["Northing",NORTH], AUTHORITY["EPSG","10481"]]
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["US survey foot",0.304800609601219]], AXIS["northing (Y)",north, ORDER[2], LENGTHUNIT["US survey foot",0.304800609601219]], 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",10481]]], TARGETCRS[ GEOGCRS["WGS 84", ENSEMBLE["World Geodetic System 1984 ensemble", MEMBER["World Geodetic System 1984 (Transit)"], MEMBER["World Geodetic System 1984 (G730)"], MEMBER["World Geodetic System 1984 (G873)"], MEMBER["World Geodetic System 1984 (G1150)"], MEMBER["World Geodetic System 1984 (G1674)"], MEMBER["World Geodetic System 1984 (G1762)"], MEMBER["World Geodetic System 1984 (G2139)"], MEMBER["World Geodetic System 1984 (G2296)"], ELLIPSOID["WGS 84",6378137,298.257223563, LENGTHUNIT["metre",1]], ENSEMBLEACCURACY[2.0]], 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["World."], BBOX[-90,-180,90,180]], ID["EPSG",4326]]], ABRIDGEDTRANSFORMATION["NAD83 to WGS 84 (21)", METHOD["NADCON", ID["EPSG",9613]], PARAMETERFILE["Latitude difference file","alhpgn.las"], PARAMETERFILE["Longitude difference file","alhpgn.los"], USAGE[ SCOPE["(null/copy) Approximation for medium and low accuracy applications assuming equality between plate-fixed static and earth-fixed dynamic CRSs, ignoring static/dynamic CRS differences."], AREA["United States (USA) - Alabama."], BBOX[30.14,-88.48,35.02,-84.89]], ID["EPSG",1717], REMARK["Parameter files are from NAD83 to NAD83(HARN) (1) (code 1474) assuming that NAD83(HARN) is equivalent to WGS 84 within the accuracy of the transformation."]]]
Definition: ESRI Well Known Text
PROJCS["NAD_1983_TWDB_GM", GEOGCS["GCS_North_American_1983", DATUM["D_North_American_1983", SPHEROID["GRS_1980",6378137.0,298.257222101], EXTENSION["PROJ4_GRIDS","us_noaa_alhpgn.tif"]], PRIMEM["Greenwich",0.0], UNIT["Degree",0.0174532925199433]], PROJECTION["Albers"], PARAMETER["False_Easting",4921250.0], PARAMETER["False_Northing",19685000.0], PARAMETER["Central_Meridian",-100.0], PARAMETER["Standard_Parallel_1",27.5], PARAMETER["Standard_Parallel_2",35.0], PARAMETER["Latitude_Of_Origin",31.25], UNIT["US survey foot",0.304800609601219]]
Definition: JSON
{ "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json", "type": "BoundCRS", "source_crs": { "type": "ProjectedCRS", "name": "NAD83 / TWDB GM", "base_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 }, "remarks": "Longitude is POSITIVE EAST. The adjustment included connections to Greenland and Mexico but the system was not adopted there. For applications with an accuracy of better than 1m replaced by NAD83(HARN) in the US and PRVI and by NAD83(CSRS) in Canada." }, "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": { "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": 10481 } }, "target_crs": { "type": "GeographicCRS", "name": "WGS 84", "datum_ensemble": { "name": "World Geodetic System 1984 ensemble", "members": [ { "name": "World Geodetic System 1984 (Transit)", "id": { "authority": "EPSG", "code": 1166 } }, { "name": "World Geodetic System 1984 (G730)", "id": { "authority": "EPSG", "code": 1152 } }, { "name": "World Geodetic System 1984 (G873)", "id": { "authority": "EPSG", "code": 1153 } }, { "name": "World Geodetic System 1984 (G1150)", "id": { "authority": "EPSG", "code": 1154 } }, { "name": "World Geodetic System 1984 (G1674)", "id": { "authority": "EPSG", "code": 1155 } }, { "name": "World Geodetic System 1984 (G1762)", "id": { "authority": "EPSG", "code": 1156 } }, { "name": "World Geodetic System 1984 (G2139)", "id": { "authority": "EPSG", "code": 1309 } }, { "name": "World Geodetic System 1984 (G2296)", "id": { "authority": "EPSG", "code": 1383 } } ], "ellipsoid": { "name": "WGS 84", "semi_major_axis": 6378137, "inverse_flattening": 298.257223563 }, "accuracy": "2.0", "id": { "authority": "EPSG", "code": 6326 } }, "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": 4326 } }, "transformation": { "name": "NAD83 to WGS 84 (21)", "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": 1717 } } }
Definition: GeoServer
10481=PROJCS["NAD83 / TWDB GM",GEOGCS["NAD83",DATUM["North_American_Datum_1983",SPHEROID["GRS 1980",6378137,298.257222101],EXTENSION["PROJ4_GRIDS","us_noaa_alhpgn.tif"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4269"]],PROJECTION["Albers_Conic_Equal_Area"],PARAMETER["latitude_of_center",31.25],PARAMETER["longitude_of_center",-100],PARAMETER["standard_parallel_1",27.5],PARAMETER["standard_parallel_2",35],PARAMETER["false_easting",4921250],PARAMETER["false_northing",19685000],UNIT["US survey foot",0.304800609601219],AXIS["Easting",EAST],AXIS["Northing",NORTH],AUTHORITY["EPSG","10481"]]
Definition: Mapnik
<?xml version="1.0" encoding="utf-8"?> <Map srs="+proj=aea +lat_0=31.25 +lon_0=-100 +lat_1=27.5 +lat_2=35 +x_0=1500000 +y_0=6000000 +ellps=GRS80 +nadgrids=us_noaa_alhpgn.tif +units=us-ft +no_defs +type=crs"> <Layer srs="+proj=aea +lat_0=31.25 +lon_0=-100 +lat_1=27.5 +lat_2=35 +x_0=1500000 +y_0=6000000 +ellps=GRS80 +nadgrids=us_noaa_alhpgn.tif +units=us-ft +no_defs +type=crs"> </Layer> </Map>
Definition: SQL (PostGIS)
INSERT into spatial_ref_sys (srid, auth_name, auth_srid, proj4text, srtext) values ( 10481, 'EPSG', 10481, '+proj=aea +lat_0=31.25 +lon_0=-100 +lat_1=27.5 +lat_2=35 +x_0=1500000 +y_0=6000000 +ellps=GRS80 +nadgrids=us_noaa_alhpgn.tif +units=us-ft +no_defs +type=crs', 'PROJCS["NAD83 / TWDB GM",GEOGCS["NAD83",DATUM["North_American_Datum_1983",SPHEROID["GRS 1980",6378137,298.257222101],EXTENSION["PROJ4_GRIDS","us_noaa_alhpgn.tif"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4269"]],PROJECTION["Albers_Conic_Equal_Area"],PARAMETER["latitude_of_center",31.25],PARAMETER["longitude_of_center",-100],PARAMETER["standard_parallel_1",27.5],PARAMETER["standard_parallel_2",35],PARAMETER["false_easting",4921250],PARAMETER["false_northing",19685000],UNIT["US survey foot",0.304800609601219],AXIS["Easting",EAST],AXIS["Northing",NORTH],AUTHORITY["EPSG","10481"]]');
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