EPSG:9311

NAD27 / US National Atlas Equal Area

Available transformations
to EPSG:4326

Selected transformation

Grid Files: AB_CSRS.DAC NTv2_0.gsb

Remarks: Steps based on concatenated transformation NAD27 to NAD83(CSRS)v4 (3) (code 9336) assuming that NAD83(CSRS)v4 is equivalent to WGS 84.

Information source: OGP

Revision date: 2020-03-14

Attributes

Unit: metre

Geodetic CRS: NAD27

Datum: North American Datum 1927

Ellipsoid: Clarke 1866

Prime meridian: Greenwich

Data source: EPSG

Information source: United States Geological Survey, Western Geographic Science Center

Revision date: 2020-03-26

Scope: Statistical analysis.

Remarks: 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.

Area of use: United States (USA) - onshore and offshore.

Coordinate system: Cartesian 2D CS. Axes: easting, northing (X,Y). Orientations: east, north. UoM: m.

Center coordinates
-963657.37 1147951.06

Projected bounds:
-1440751.88 489189.76
-557529.55 1809991.08

WGS84 bounds:
-120.0 48.99
-109.98 60.0

Canada - Alberta.
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Definition: OGC Well Known Text 2 (2019)

BOUNDCRS[
    SOURCECRS[
        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]],
                    ID["EPSG",9311]]],
            TARGETCRS[
                GEOGCRS["NAD83",
                    DATUM["North American Datum 1983",
                        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]],
                    ID["EPSG",4269]]],
            ABRIDGEDTRANSFORMATION["NAD27 to NAD83 (4)",
                METHOD["NTv2",
                    ID["EPSG",9615]],
                PARAMETERFILE["Latitude and longitude difference file","NTv2_0.gsb"],
                ID["EPSG",1313]]]],
    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)"],
                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 (8)",
        METHOD["NTv2",
            ID["EPSG",9615]],
        PARAMETERFILE["Latitude and longitude difference file","AB_CSRS.DAC"],
        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["Canada - Alberta."],
            BBOX[48.99,-120,60,-109.98]],
        ID["EPSG",1702],
        REMARK["Parameter file is from NAD83 to NAD83(CSRS)v4 (3) (code 9244) assuming that NAD83(CSRS)v4 is equivalent to WGS 84 within the accuracy of the transformation. This file AB_CSRS.DAC will need to be renamed to AB_CSRS.gsb to run in some software."]]]

Definition: PROJ.4

+proj=laea +R_A +lat_0=45 +lon_0=-100 +x_0=0 +y_0=0 +ellps=clrk66 +nadgrids=AB_CSRS.DAC +units=m +no_defs +type=crs

Definition: JavaScript (Proj4js)

proj4.defs("EPSG:9311","+proj=laea +R_A +lat_0=45 +lon_0=-100 +x_0=0 +y_0=0 +ellps=clrk66 +nadgrids=AB_CSRS.DAC +units=m +no_defs +type=crs");

Definition: JSON

{
    "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json",
    "type": "BoundCRS",
    "source_crs": {
        "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",
            "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
            }
        },
        "transformation": {
            "name": "NAD27 to NAD83 (4)",
            "method": {
                "name": "NTv2",
                "id": {
                    "authority": "EPSG",
                    "code": 9615
                }
            },
            "parameters": [
                {
                    "name": "Latitude and longitude difference file",
                    "value": "NTv2_0.gsb",
                    "id": {
                        "authority": "EPSG",
                        "code": 8656
                    }
                }
            ],
            "id": {
                "authority": "EPSG",
                "code": 1313
            }
        }
    },
    "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
                    }
                }
            ],
            "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 (8)",
        "source_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
            }
        },
        "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": 1702
        }
    }
}

Definition: MapServer - MAPfile

PROJECTION
	"proj=laea"
	"R_A"
	"lat_0=45"
	"lon_0=-100"
	"x_0=0"
	"y_0=0"
	"ellps=clrk66"
	"nadgrids=AB_CSRS.DAC"
	"units=m"
	"no_defs"
	"type=crs"
END

Definition: Mapnik

<?xml version="1.0" encoding="utf-8"?>
<Map srs="+proj=laea +R_A +lat_0=45 +lon_0=-100 +x_0=0 +y_0=0 +ellps=clrk66 +nadgrids=AB_CSRS.DAC +units=m +no_defs +type=crs">
	<Layer srs="+proj=laea +R_A +lat_0=45 +lon_0=-100 +x_0=0 +y_0=0 +ellps=clrk66 +nadgrids=AB_CSRS.DAC +units=m +no_defs +type=crs">
	</Layer>
</Map>