EPSG:29903

TM75 / Irish Grid

Selected transformation

Method: NTv2

Grid Files: tm75_etrs89.gsb

Remarks: Parameter values taken from TM75 to ETRS89 (3) (tfm code 6946) assuming that ETRS89 is coincident with WGS 84 within the accuracy of the tfm. Within accuracy of the tfm equivalent to TM75 to WGS 84 (1) (tfm code 1042).

Information source: OGP

Revision date: 2021-09-23

Attributes

Unit: metre

Geodetic CRS: TM75

Datum: Geodetic Datum of 1965

Ellipsoid: Airy Modified 1849

Prime meridian: Greenwich

Data source: EPSG

Information source: Ordnance Survey of Ireland

Revision date: 2001-11-06

Scope: Engineering survey, topographic mapping.

Remarks: Replaces both OSNI 1952 / Irish National Grid (code 29901) and TM65 / Irish Grid (code 29902) from 1975. Replaced by IRENET95 / Irish Transverse Mercator (code 2157) from 1/1/2001.

Area of use: Ireland - onshore. United Kingdom (UK) - Northern Ireland (Ulster) - onshore.

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

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Definition: Well Known Text (WKT)

PROJCS["TM75 / Irish Grid",
    GEOGCS["TM75",
        DATUM["Geodetic_Datum_of_1965",
            SPHEROID["Airy Modified 1849",6377340.189,299.3249646],
            EXTENSION["PROJ4_GRIDS","tm75_etrs89.gsb"]],
        PRIMEM["Greenwich",0],
        UNIT["degree",0.0174532925199433,
            AUTHORITY["EPSG","9122"]],
        AUTHORITY["EPSG","4300"]],
    PROJECTION["Transverse_Mercator"],
    PARAMETER["latitude_of_origin",53.5],
    PARAMETER["central_meridian",-8],
    PARAMETER["scale_factor",1.000035],
    PARAMETER["false_easting",200000],
    PARAMETER["false_northing",250000],
    UNIT["metre",1],
    AXIS["Easting",EAST],
    AXIS["Northing",NORTH],
    AUTHORITY["EPSG","29903"]]

Definition: ESRI WKT

PROJCS["TM75_Irish_Grid",GEOGCS["GCS_TM75",DATUM["D_TM75",SPHEROID["Airy_Modified",6377340.189,299.3249646],EXTENSION["PROJ4_GRIDS","tm75_etrs89.gsb"]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Transverse_Mercator"],PARAMETER["False_Easting",200000.0],PARAMETER["False_Northing",250000.0],PARAMETER["Central_Meridian",-8.0],PARAMETER["Scale_Factor",1.000035],PARAMETER["Latitude_Of_Origin",53.5],UNIT["Meter",1.0]]

Definition: PROJ.4

+proj=tmerc +lat_0=53.5 +lon_0=-8 +k=1.000035 +x_0=200000 +y_0=250000 +a=6377340.189 +rf=299.3249646 +nadgrids=tm75_etrs89.gsb +units=m +no_defs +type=crs

Definition: JavaScript (Proj4js)

proj4.defs("EPSG:29903","+proj=tmerc +lat_0=53.5 +lon_0=-8 +k=1.000035 +x_0=200000 +y_0=250000 +a=6377340.189 +rf=299.3249646 +nadgrids=tm75_etrs89.gsb +units=m +no_defs +type=crs");

Definition: JSON

{
    "$schema": "https://proj.org/schemas/v0.4/projjson.schema.json",
    "type": "BoundCRS",
    "source_crs": {
        "type": "ProjectedCRS",
        "name": "TM75 / Irish Grid",
        "base_crs": {
            "name": "TM75",
            "datum": {
                "type": "GeodeticReferenceFrame",
                "name": "Geodetic Datum of 1965",
                "ellipsoid": {
                    "name": "Airy Modified 1849",
                    "semi_major_axis": 6377340.189,
                    "inverse_flattening": 299.3249646
                }
            },
            "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": 4300
            }
        },
        "conversion": {
            "name": "Irish Grid",
            "method": {
                "name": "Transverse Mercator",
                "id": {
                    "authority": "EPSG",
                    "code": 9807
                }
            },
            "parameters": [
                {
                    "name": "Latitude of natural origin",
                    "value": 53.5,
                    "unit": "degree",
                    "id": {
                        "authority": "EPSG",
                        "code": 8801
                    }
                },
                {
                    "name": "Longitude of natural origin",
                    "value": -8,
                    "unit": "degree",
                    "id": {
                        "authority": "EPSG",
                        "code": 8802
                    }
                },
                {
                    "name": "Scale factor at natural origin",
                    "value": 1.000035,
                    "unit": "unity",
                    "id": {
                        "authority": "EPSG",
                        "code": 8805
                    }
                },
                {
                    "name": "False easting",
                    "value": 200000,
                    "unit": "metre",
                    "id": {
                        "authority": "EPSG",
                        "code": 8806
                    }
                },
                {
                    "name": "False northing",
                    "value": 250000,
                    "unit": "metre",
                    "id": {
                        "authority": "EPSG",
                        "code": 8807
                    }
                }
            ]
        },
        "coordinate_system": {
            "subtype": "Cartesian",
            "axis": [
                {
                    "name": "Easting",
                    "abbreviation": "E",
                    "direction": "east",
                    "unit": "metre"
                },
                {
                    "name": "Northing",
                    "abbreviation": "N",
                    "direction": "north",
                    "unit": "metre"
                }
            ]
        },
        "id": {
            "authority": "EPSG",
            "code": 29903
        }
    },
    "target_crs": {
        "type": "GeographicCRS",
        "name": "WGS 84",
        "datum_ensemble": {
            "name": "World Geodetic System 1984 ensemble",
            "members": [
                {
                    "name": "World Geodetic System 1984 (Transit)"
                },
                {
                    "name": "World Geodetic System 1984 (G730)"
                },
                {
                    "name": "World Geodetic System 1984 (G873)"
                },
                {
                    "name": "World Geodetic System 1984 (G1150)"
                },
                {
                    "name": "World Geodetic System 1984 (G1674)"
                },
                {
                    "name": "World Geodetic System 1984 (G1762)"
                },
                {
                    "name": "World Geodetic System 1984 (G2139)"
                }
            ],
            "ellipsoid": {
                "name": "WGS 84",
                "semi_major_axis": 6378137,
                "inverse_flattening": 298.257223563
            },
            "accuracy": "2.0"
        },
        "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": "TM75 to WGS 84 (4)",
        "method": {
            "name": "NTv2",
            "id": {
                "authority": "EPSG",
                "code": 9615
            }
        },
        "parameters": [
            {
                "name": "Latitude and longitude difference file",
                "value": "tm75_etrs89.gsb"
            }
        ],
        "id": {
            "authority": "EPSG",
            "code": 6947
        }
    }
}

Definition: GeoServer

29903=PROJCS["TM75 / Irish Grid",GEOGCS["TM75",DATUM["Geodetic_Datum_of_1965",SPHEROID["Airy Modified 1849",6377340.189,299.3249646],EXTENSION["PROJ4_GRIDS","tm75_etrs89.gsb"]],PRIMEM["Greenwich",0],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4300"]],PROJECTION["Transverse_Mercator"],PARAMETER["latitude_of_origin",53.5],PARAMETER["central_meridian",-8],PARAMETER["scale_factor",1.000035],PARAMETER["false_easting",200000],PARAMETER["false_northing",250000],UNIT["metre",1],AXIS["Easting",EAST],AXIS["Northing",NORTH],AUTHORITY["EPSG","29903"]]

Definition: MapServer - MAPfile

PROJECTION
	"proj=tmerc"
	"lat_0=53.5"
	"lon_0=-8"
	"k=1.000035"
	"x_0=200000"
	"y_0=250000"
	"a=6377340.189"
	"rf=299.3249646"
	"nadgrids=tm75_etrs89.gsb"
	"units=m"
	"no_defs"
	"type=crs"
END

Definition: Mapnik

<?xml version="1.0" encoding="utf-8"?>
<Map srs="+proj=tmerc +lat_0=53.5 +lon_0=-8 +k=1.000035 +x_0=200000 +y_0=250000 +a=6377340.189 +rf=299.3249646 +nadgrids=tm75_etrs89.gsb +units=m +no_defs +type=crs">
	<Layer srs="+proj=tmerc +lat_0=53.5 +lon_0=-8 +k=1.000035 +x_0=200000 +y_0=250000 +a=6377340.189 +rf=299.3249646 +nadgrids=tm75_etrs89.gsb +units=m +no_defs +type=crs">
	</Layer>
</Map>

Definition: SQL (PostGIS)

INSERT into spatial_ref_sys (srid, auth_name, auth_srid, proj4text, srtext) values ( 29903, 'EPSG', 29903, '+proj=tmerc +lat_0=53.5 +lon_0=-8 +k=1.000035 +x_0=200000 +y_0=250000 +a=6377340.189 +rf=299.3249646 +nadgrids=tm75_etrs89.gsb +units=m +no_defs +type=crs', 'PROJCS["TM75 / Irish Grid",GEOGCS["TM75",DATUM["Geodetic_Datum_of_1965",SPHEROID["Airy Modified 1849",6377340.189,299.3249646],EXTENSION["PROJ4_GRIDS","tm75_etrs89.gsb"]],PRIMEM["Greenwich",0],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4300"]],PROJECTION["Transverse_Mercator"],PARAMETER["latitude_of_origin",53.5],PARAMETER["central_meridian",-8],PARAMETER["scale_factor",1.000035],PARAMETER["false_easting",200000],PARAMETER["false_northing",250000],UNIT["metre",1],AXIS["Easting",EAST],AXIS["Northing",NORTH],AUTHORITY["EPSG","29903"]]');

Definition: OGC WKT

PROJCS["TM75 / Irish Grid",GEOGCS["TM75",DATUM["Geodetic_Datum_of_1965",SPHEROID["Airy Modified 1849",6377340.189,299.3249646],EXTENSION["PROJ4_GRIDS","tm75_etrs89.gsb"]],PRIMEM["Greenwich",0],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4300"]],PROJECTION["Transverse_Mercator"],PARAMETER["latitude_of_origin",53.5],PARAMETER["central_meridian",-8],PARAMETER["scale_factor",1.000035],PARAMETER["false_easting",200000],PARAMETER["false_northing",250000],UNIT["metre",1],AXIS["Easting",EAST],AXIS["Northing",NORTH],AUTHORITY["EPSG","29903"]]

Definition: OGC WKT 2 (2019)

BOUNDCRS[SOURCECRS[PROJCRS["TM75 / Irish Grid",BASEGEOGCRS["TM75",DATUM["Geodetic Datum of 1965",ELLIPSOID["Airy Modified 1849",6377340.189,299.3249646,LENGTHUNIT["metre",1]]],PRIMEM["Greenwich",0,ANGLEUNIT["degree",0.0174532925199433]],ID["EPSG",4300]],CONVERSION["Irish Grid",METHOD["Transverse Mercator",ID["EPSG",9807]],PARAMETER["Latitude of natural origin",53.5,ANGLEUNIT["degree",0.0174532925199433],ID["EPSG",8801]],PARAMETER["Longitude of natural origin",-8,ANGLEUNIT["degree",0.0174532925199433],ID["EPSG",8802]],PARAMETER["Scale factor at natural origin",1.000035,SCALEUNIT["unity",1],ID["EPSG",8805]],PARAMETER["False easting",200000,LENGTHUNIT["metre",1],ID["EPSG",8806]],PARAMETER["False northing",250000,LENGTHUNIT["metre",1],ID["EPSG",8807]]],CS[Cartesian,2],AXIS["(E)",east,ORDER[1],LENGTHUNIT["metre",1]],AXIS["(N)",north,ORDER[2],LENGTHUNIT["metre",1]],USAGE[SCOPE["Engineering survey, topographic mapping."],AREA["Ireland - onshore. United Kingdom (UK) - Northern Ireland (Ulster) - onshore."],BBOX[51.39,-10.56,55.43,-5.34]],ID["EPSG",29903]]],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["TM75 to WGS 84 (4)",METHOD["NTv2",ID["EPSG",9615]],PARAMETERFILE["Latitude and longitude difference file","tm75_etrs89.gsb"],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["Ireland - onshore. United Kingdom (UK) - Northern Ireland (Ulster) - onshore."],BBOX[51.39,-10.56,55.43,-5.34]],ID["EPSG",6947],REMARK["Parameter values taken from TM75 to ETRS89 (3) (tfm code 6946) assuming that ETRS89 is coincident with WGS 84 within the accuracy of the tfm. Within accuracy of the tfm equivalent to TM75 to WGS 84 (1) (tfm code 1042)."]]]