EPSG:9174

NAD83(NSRS2007) to NAVD88 height (2)

Attributes

Geodetic CRS: NAD83(NSRS2007)

Datum: NAD83 (National Spatial Reference System 2007)

Ellipsoid: GRS 1980

Prime meridian: Greenwich

Data source: EPSG

Information source: National Geodetic Survey, http://www.ngs.noaa.gov/GEOID/

Revision date: 2020-06-17

Scope: Derivation of approximate gravity-related heights from GNSS observations.

Remarks: Uses Geoid09 hybrid model. Replaced by Geoid12 model (CT code 6327).

Method: Geographic3D to GravityRelatedHeight (gtx)

Area of use: United States (USA) - Alaska.

Description: (0,)

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Definition: OGC Well Known Text 2 (2019)

COORDINATEOPERATION["NAD83(NSRS2007) to NAVD88 height (2)",
    VERSION["NGS-US AK 09"],
    SOURCECRS[
        GEOGCRS["NAD83(NSRS2007)",
            DATUM["NAD83 (National Spatial Reference System 2007)",
                ELLIPSOID["GRS 1980",6378137,298.257222101,
                    LENGTHUNIT["metre",1]]],
            PRIMEM["Greenwich",0,
                ANGLEUNIT["degree",0.0174532925199433]],
            CS[ellipsoidal,3],
                AXIS["geodetic latitude (Lat)",north,
                    ORDER[1],
                    ANGLEUNIT["degree",0.0174532925199433]],
                AXIS["geodetic longitude (Lon)",east,
                    ORDER[2],
                    ANGLEUNIT["degree",0.0174532925199433]],
                AXIS["ellipsoidal height (h)",up,
                    ORDER[3],
                    LENGTHUNIT["metre",1]],
            ID["EPSG",4893]]],
    TARGETCRS[
        VERTCRS["NAVD88 height",
            VDATUM["North American Vertical Datum 1988"],
            CS[vertical,1],
                AXIS["gravity-related height (H)",up,
                    LENGTHUNIT["metre",1]],
            ID["EPSG",5703]]],
    METHOD["Geographic3D to GravityRelatedHeight (gtx)",
        ID["EPSG",9665]],
    PARAMETERFILE["Geoid (height correction) model file","geoid09_ak.bin"],
    OPERATIONACCURACY[0.05],
    USAGE[
        SCOPE["Derivation of approximate gravity-related heights from GNSS observations."],
        AREA["United States (USA) - Alaska."],
        BBOX[51.3,172.42,71.4,-129.99]],
    ID["EPSG",9174],
    REMARK["Uses Geoid09 hybrid model. Replaced by Geoid12 model (CT code 6327)."]]

Definition: PROJ.4

+proj=pipeline +step +proj=axisswap +order=2,1 +step +proj=unitconvert +xy_in=deg +xy_out=rad +step +inv +proj=vgridshift +grids=us_noaa_geoid09_ak.tif +multiplier=1 +step +proj=unitconvert +xy_in=rad +xy_out=deg +step +proj=axisswap +order=2,1

Definition: JavaScript (Proj4js)

proj4.defs("EPSG:9174","+proj=pipeline +step +proj=axisswap +order=2,1 +step +proj=unitconvert +xy_in=deg +xy_out=rad +step +inv +proj=vgridshift +grids=us_noaa_geoid09_ak.tif +multiplier=1 +step +proj=unitconvert +xy_in=rad +xy_out=deg +step +proj=axisswap +order=2,1");

Definition: JSON

{
    "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json",
    "type": "Transformation",
    "name": "NAD83(NSRS2007) to NAVD88 height (2)",
    "source_crs": {
        "type": "GeographicCRS",
        "name": "NAD83(NSRS2007)",
        "datum": {
            "type": "GeodeticReferenceFrame",
            "name": "NAD83 (National Spatial Reference System 2007)",
            "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"
                },
                {
                    "name": "Ellipsoidal height",
                    "abbreviation": "h",
                    "direction": "up",
                    "unit": "metre"
                }
            ]
        },
        "id": {
            "authority": "EPSG",
            "code": 4893
        }
    },
    "target_crs": {
        "type": "VerticalCRS",
        "name": "NAVD88 height",
        "datum": {
            "type": "VerticalReferenceFrame",
            "name": "North American Vertical Datum 1988"
        },
        "coordinate_system": {
            "subtype": "vertical",
            "axis": [
                {
                    "name": "Gravity-related height",
                    "abbreviation": "H",
                    "direction": "up",
                    "unit": "metre"
                }
            ]
        },
        "id": {
            "authority": "EPSG",
            "code": 5703
        }
    },
    "method": {
        "name": "Geographic3D to GravityRelatedHeight (gtx)",
        "id": {
            "authority": "EPSG",
            "code": 9665
        }
    },
    "parameters": [
        {
            "name": "Geoid (height correction) model file",
            "value": "geoid09_ak.bin",
            "id": {
                "authority": "EPSG",
                "code": 8666
            }
        }
    ],
    "accuracy": "0.05",
    "scope": "Derivation of approximate gravity-related heights from GNSS observations.",
    "area": "United States (USA) - Alaska.",
    "bbox": {
        "south_latitude": 51.3,
        "west_longitude": 172.42,
        "north_latitude": 71.4,
        "east_longitude": -129.99
    },
    "id": {
        "authority": "EPSG",
        "code": 9174
    },
    "remarks": "Uses Geoid09 hybrid model. Replaced by Geoid12 model (CT code 6327)."
}

Definition: MapServer - MAPfile

PROJECTION
	"proj=pipeline"
	"step"
	"proj=axisswap"
	"order=2,1"
	"step"
	"proj=unitconvert"
	"xy_in=deg"
	"xy_out=rad"
	"step"
	"inv"
	"proj=vgridshift"
	"grids=us_noaa_geoid09_ak.tif"
	"multiplier=1"
	"step"
	"proj=unitconvert"
	"xy_in=rad"
	"xy_out=deg"
	"step"
	"proj=axisswap"
	"order=2,1"
END

Definition: Mapnik

<?xml version="1.0" encoding="utf-8"?>
<Map srs="+proj=pipeline +step +proj=axisswap +order=2,1 +step +proj=unitconvert +xy_in=deg +xy_out=rad +step +inv +proj=vgridshift +grids=us_noaa_geoid09_ak.tif +multiplier=1 +step +proj=unitconvert +xy_in=rad +xy_out=deg +step +proj=axisswap +order=2,1">
	<Layer srs="+proj=pipeline +step +proj=axisswap +order=2,1 +step +proj=unitconvert +xy_in=deg +xy_out=rad +step +inv +proj=vgridshift +grids=us_noaa_geoid09_ak.tif +multiplier=1 +step +proj=unitconvert +xy_in=rad +xy_out=deg +step +proj=axisswap +order=2,1">
	</Layer>
</Map>

Definition: SQL (PostGIS)

INSERT into spatial_ref_sys (srid, auth_name, auth_srid, proj4text, srtext) values ( 9174, 'EPSG', 9174, '+proj=pipeline +step +proj=axisswap +order=2,1 +step +proj=unitconvert +xy_in=deg +xy_out=rad +step +inv +proj=vgridshift +grids=us_noaa_geoid09_ak.tif +multiplier=1 +step +proj=unitconvert +xy_in=rad +xy_out=deg +step +proj=axisswap +order=2,1', 'None');