AB_CSRS.DAC
This gridded difference file AB_CSRS.DAC will need to be renamed to AB_CSRS.gsb to run in some software suites. Formats identical, but AB file is provincial fit only. Can be taken as an approximate transformation NAD83 to WGS 84 - see code 1702.
Geodetic Control Section; Land and Forest Svc; Alberta Environment; http://www.gov.ab.ca/env/land/dos/ or email to geoff.banham@gov.ab.ca
2000-10-19
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.
417329.73 8575195.34
-42420.5 7972737.37
825501.72 9151751.25
-120.0 48.99
-109.98 60.0
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(CSRS98)", DATUM["NAD83 Canadian Spatial Reference System", 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 minute second hemisphere",0.0174532925199433]], AXIS["geodetic longitude (Long)",east, ORDER[2], ANGLEUNIT["degree minute second hemisphere",0.0174532925199433]], USAGE[ SCOPE["Geodesy."], AREA["Canada - Alberta; New Brunswick; Saskatchewan; Prince Edward Island; and Quebec."], BBOX[44.61,-120,62.56,-57.1]], ID["EPSG",4140]]], ABRIDGEDTRANSFORMATION["NAD83 to NAD83(CSRS98) (3)", METHOD["NTv2", ID["EPSG",9615]], PARAMETERFILE["Latitude and longitude difference file","AB_CSRS.DAC"], USAGE[ SCOPE["?"], AREA["Canada - Alberta."], BBOX[48.99,-120,60,-109.98]], ID["EPSG",1752], REMARK["This gridded difference file AB_CSRS.DAC will need to be renamed to AB_CSRS.gsb to run in some software suites. Formats identical, but AB file is provincial fit only. Can be taken as an approximate transformation NAD83 to WGS 84 - see code 1702."]]]
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(CSRS98)", "datum": { "type": "GeodeticReferenceFrame", "name": "NAD83 Canadian Spatial Reference System", "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": { "type": "AngularUnit", "name": "degree minute second hemisphere", "conversion_factor": 0.0174532925199433 } }, { "name": "Geodetic longitude", "abbreviation": "Long", "direction": "east", "unit": { "type": "AngularUnit", "name": "degree minute second hemisphere", "conversion_factor": 0.0174532925199433 } } ] }, "id": { "authority": "EPSG", "code": 4140 } }, "transformation": { "name": "NAD83 to NAD83(CSRS98) (3)", "method": { "name": "NTv2", "id": { "authority": "EPSG", "code": 9615 } }, "parameters": [ { "name": "Latitude and longitude difference file", "value": "AB_CSRS.DAC", "id": { "authority": "EPSG", "code": 8656 } } ], "id": { "authority": "EPSG", "code": 1752 } } }
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 +datum=NAD83 +units=m +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 +datum=NAD83 +units=m +no_defs +type=crs"> </Layer> </Map>