AB_CSRS.DAC
This gridded difference file AB_CSRS.DAC may need to be renamed to AB_CSRS.gsb or AB_CSRSV4.gsb to run in some software. 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://www3.gov.ab.ca/env/land/dos/
2023-07-17
Engineering survey, topographic mapping.
For applications with an accuracy of better than 1m, replaced by NAD83(HARN) / SPCS.
Cartesian 2D CS. Axes: easting, northing (X,Y). Orientations: east, north. UoM: m.
-1156501.38 3075117.3
-1753978.73 2356726.06
-637603.72 3784277.97
-120.0 48.99
-109.98 60.0
Definition: OGC Well Known Text 2 (2019)
BOUNDCRS[ SOURCECRS[ PROJCRS["NAD83 / Alabama West", 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 Alabama West zone (meter)", METHOD["Transverse Mercator", ID["EPSG",9807]], PARAMETER["Latitude of natural origin",30, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8801]], PARAMETER["Longitude of natural origin",-87.5, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8802]], PARAMETER["Scale factor at natural origin",0.999933333, SCALEUNIT["unity",1], ID["EPSG",8805]], PARAMETER["False easting",600000, 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) - Alabama west of approximately 86°37'W - counties Autauga; Baldwin; Bibb; Blount; Butler; Chilton; Choctaw; Clarke; Colbert; Conecuh; Cullman; Dallas; Escambia; Fayette; Franklin; Greene; Hale; Jefferson; Lamar; Lauderdale; Lawrence; Limestone; Lowndes; Marengo; Marion; Mobile; Monroe; Morgan; Perry; Pickens; Shelby; Sumter; Tuscaloosa; Walker; Washington; Wilcox; Winston."], BBOX[30.14,-88.48,35.02,-86.3]], ID["EPSG",26930]]], TARGETCRS[ GEOGCRS["NAD83(CSRS)v4", DATUM["North American Datum of 1983 (CSRS) version 4", 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["Canada - onshore and offshore - Alberta; British Columbia; Manitoba; New Brunswick; Newfoundland and Labrador; Northwest Territories; Nova Scotia; Nunavut; Ontario; Prince Edward Island; Quebec; Saskatchewan; Yukon."], BBOX[38.21,-141.01,86.46,-40.73]], ID["EPSG",8246]]], ABRIDGEDTRANSFORMATION["NAD83 to NAD83(CSRS)v4 (3)", METHOD["NTv2", ID["EPSG",9615]], PARAMETERFILE["Latitude and longitude difference file","AB_CSRS.DAC"], USAGE[ SCOPE["Transformation of coordinates at 1m to 2m level of accuracy."], AREA["Canada - Alberta."], BBOX[48.99,-120,60,-109.98]], ID["EPSG",9244], REMARK["This gridded difference file AB_CSRS.DAC may need to be renamed to AB_CSRS.gsb or AB_CSRSV4.gsb to run in some software. 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 / Alabama West", "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 Alabama West zone (meter)", "method": { "name": "Transverse Mercator", "id": { "authority": "EPSG", "code": 9807 } }, "parameters": [ { "name": "Latitude of natural origin", "value": 30, "unit": "degree", "id": { "authority": "EPSG", "code": 8801 } }, { "name": "Longitude of natural origin", "value": -87.5, "unit": "degree", "id": { "authority": "EPSG", "code": 8802 } }, { "name": "Scale factor at natural origin", "value": 0.999933333, "unit": "unity", "id": { "authority": "EPSG", "code": 8805 } }, { "name": "False easting", "value": 600000, "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": 26930 } }, "target_crs": { "type": "GeographicCRS", "name": "NAD83(CSRS)v4", "datum": { "type": "GeodeticReferenceFrame", "name": "North American Datum of 1983 (CSRS) version 4", "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": 8246 } }, "transformation": { "name": "NAD83 to NAD83(CSRS)v4 (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": 9244 } } }
Definition: Mapnik
<?xml version="1.0" encoding="utf-8"?> <Map srs="+proj=tmerc +lat_0=30 +lon_0=-87.5 +k=0.999933333 +x_0=600000 +y_0=0 +datum=NAD83 +units=m +no_defs +type=crs"> <Layer srs="+proj=tmerc +lat_0=30 +lon_0=-87.5 +k=0.999933333 +x_0=600000 +y_0=0 +datum=NAD83 +units=m +no_defs +type=crs"> </Layer> </Map>