EPSG:8904

TWVD 2001 height

Attributes

Unit: metre

Geodetic CRS: TWVD 2001 height

Datum: Taiwan Vertical Datum 2001

Data source: EPSG

Information source: National Land Surveying and Mapping Center, Ministry of the Interior, and Satellite Service Center, Department of Land Administration.

Revision date: 2019-03-09

Scope: Geodesy, engineering survey, topographic mapping.

Remarks: Replaces TWVD79.

Area of use: Taiwan, Republic of China - onshore - Taiwan Island.

Coordinate system: Vertical CS. Axis: height (H). Orientation: up. UoM: m.

Center coordinates
23.61 121.03

Projected bounds:
21.87 119.99
25.34 122.06

WGS84 bounds:
119.99 21.87
122.06 25.34

Taiwan, Republic of China - onshore - Taiwan Island.
MapTiler banner

Definition: OGC Well Known Text

VERT_CS["TWVD 2001 height",
    VERT_DATUM["Taiwan Vertical Datum 2001",2005,
        AUTHORITY["EPSG","1224"]],
    UNIT["metre",1,
        AUTHORITY["EPSG","9001"]],
    AXIS["Gravity-related height",UP],
    AUTHORITY["EPSG","8904"]]

Definition: OGC Well Known Text 2 (2019)

VERTCRS["TWVD 2001 height",
    VDATUM["Taiwan Vertical Datum 2001"],
    CS[vertical,1],
        AXIS["gravity-related height (H)",up,
            LENGTHUNIT["metre",1]],
    USAGE[
        SCOPE["Geodesy, engineering survey, topographic mapping."],
        AREA["Taiwan, Republic of China - onshore - Taiwan Island."],
        BBOX[21.87,119.99,25.34,122.06]],
    ID["EPSG",8904]]

Definition: ESRI Well Known Text

VERTCS["TWVD_2001_height",
    VDATUM["Taiwan_Vertical_Datum_2001"],
    PARAMETER["Vertical_Shift",0.0],
    PARAMETER["Direction",1.0],
    UNIT["Meter",1.0]]

Definition: PROJ.4

+vunits=m +no_defs +type=crs

Definition: JavaScript (Proj4js)

proj4.defs("EPSG:8904","+vunits=m +no_defs +type=crs");

Definition: JSON

{
    "$schema": "https://proj.org/schemas/v0.5/projjson.schema.json",
    "type": "VerticalCRS",
    "name": "TWVD 2001 height",
    "datum": {
        "type": "VerticalReferenceFrame",
        "name": "Taiwan Vertical Datum 2001"
    },
    "coordinate_system": {
        "subtype": "vertical",
        "axis": [
            {
                "name": "Gravity-related height",
                "abbreviation": "H",
                "direction": "up",
                "unit": "metre"
            }
        ]
    },
    "scope": "Geodesy, engineering survey, topographic mapping.",
    "area": "Taiwan, Republic of China - onshore - Taiwan Island.",
    "bbox": {
        "south_latitude": 21.87,
        "west_longitude": 119.99,
        "north_latitude": 25.34,
        "east_longitude": 122.06
    },
    "id": {
        "authority": "EPSG",
        "code": 8904
    }
}

Definition: GeoServer

8904=VERT_CS["TWVD 2001 height",VERT_DATUM["Taiwan Vertical Datum 2001",2005,AUTHORITY["EPSG","1224"]],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AXIS["Gravity-related height",UP],AUTHORITY["EPSG","8904"]]

Definition: MapServer - MAPfile

PROJECTION
	"vunits=m"
	"no_defs"
	"type=crs"
END

Definition: Mapnik

<?xml version="1.0" encoding="utf-8"?>
<Map srs="+vunits=m +no_defs +type=crs">
	<Layer srs="+vunits=m +no_defs +type=crs">
	</Layer>
</Map>

Definition: SQL (PostGIS)

INSERT into spatial_ref_sys (srid, auth_name, auth_srid, proj4text, srtext) values ( 8904, 'EPSG', 8904, '+vunits=m +no_defs +type=crs', 'VERT_CS["TWVD 2001 height",VERT_DATUM["Taiwan Vertical Datum 2001",2005,AUTHORITY["EPSG","1224"]],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AXIS["Gravity-related height",UP],AUTHORITY["EPSG","8904"]]');