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.
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
United States Geological Survey, Western Geographic Science Center
2020-03-26
Statistical analysis.
Uses spherical projection formulas. USGS documentation describes sphere as derived from GRS80/WGS 84 ellipsoid but that actually used is Clarke 1866. For 1:1million and smaller scale maps there is no significant difference.
United States (USA) - onshore and offshore.
Cartesian 2D CS. Axes: easting, northing (X,Y). Orientations: east, north. UoM: m.
-963725.78 1147972.11
-1440839.87 489196.87
-557583.12 1810019.23
-120.0 48.99
-109.98 60.0
Definition: OGC Well Known Text 2 (2019)
BOUNDCRS[ SOURCECRS[ PROJCRS["NAD27 / US National Atlas Equal Area", BASEGEOGCRS["NAD27", DATUM["North American Datum 1927", ELLIPSOID["Clarke 1866",6378206.4,294.978698213898, LENGTHUNIT["metre",1]]], PRIMEM["Greenwich",0, ANGLEUNIT["degree",0.0174532925199433]], ID["EPSG",4267]], CONVERSION["US National Atlas Equal Area", METHOD["Lambert Azimuthal Equal Area (Spherical)", ID["EPSG",1027]], PARAMETER["Latitude of natural origin",45, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8801]], PARAMETER["Longitude of natural origin",-100, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8802]], PARAMETER["False easting",0, 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["Statistical analysis."], AREA["United States (USA) - onshore and offshore."], BBOX[15.56,167.65,74.71,-65.69]], ID["EPSG",9311]]], 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["Transformation of coordinates at 1m to 2m level of accuracy."], AREA["Canada - Alberta."], BBOX[48.99,-120,60,-109.98]], ID["EPSG",1602], 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."]]]
Definition: JSON
{ "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json", "type": "BoundCRS", "source_crs": { "type": "ProjectedCRS", "name": "NAD27 / US National Atlas Equal Area", "base_crs": { "name": "NAD27", "datum": { "type": "GeodeticReferenceFrame", "name": "North American Datum 1927", "ellipsoid": { "name": "Clarke 1866", "semi_major_axis": 6378206.4, "semi_minor_axis": 6356583.8 } }, "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": 4267 } }, "conversion": { "name": "US National Atlas Equal Area", "method": { "name": "Lambert Azimuthal Equal Area (Spherical)", "id": { "authority": "EPSG", "code": 1027 } }, "parameters": [ { "name": "Latitude of natural origin", "value": 45, "unit": "degree", "id": { "authority": "EPSG", "code": 8801 } }, { "name": "Longitude of natural origin", "value": -100, "unit": "degree", "id": { "authority": "EPSG", "code": 8802 } }, { "name": "False easting", "value": 0, "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": 9311 } }, "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": 1602 } } }
Definition: Mapnik
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