NAD83 (National Spatial Reference System 2007)
EPSG
National Geodetic Survey, http://www.ngs.noaa.gov/GEOID/
2020-06-17
Derivation of approximate gravity-related heights from GNSS observations.
Uses Geoid09 hybrid model. Replaced by Geoid12 model (CT code 6327).
Geographic3D to GravityRelatedHeight (gtx)
(0,)
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');