EPSG:9983

COORDINATEOPERATION["NAD83(CSRS)v3 to CGVD28 height (1)",
    VERSION["NRC-Can CGG2000"],
    SOURCECRS[
        GEOGCRS["NAD83(CSRS)v3",
            DATUM["North American Datum of 1983 (CSRS) version 3",
                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",8239]]],
    TARGETCRS[
        VERTCRS["CGVD28 height",
            VDATUM["Canadian Geodetic Vertical Datum of 1928"],
            CS[vertical,1],
                AXIS["gravity-related height (H)",up,
                    LENGTHUNIT["metre",1]],
            ID["EPSG",5713]]],
    METHOD["Geographic3D to GravityRelatedHeight (NRCan byn)",
        ID["EPSG",1060]],
    PARAMETERFILE["Geoid (height correction) model file","HT2_1997.byn"],
    OPERATIONACCURACY[0.05],
    USAGE[
        SCOPE["Derivation of gravity-related heights from GNSS observations."],
        AREA["Canada - onshore - Alberta; British Columbia; Manitoba south of 57°N; New Brunswick; Northwest Territories south west of a line between 60°N, 110°W and the coast at 132°W; Nova Scotia; Ontario south of 52°N; Prince Edward Island; Quebec - mainland west of 66°W and south of 55°N; Saskatchewan south of 55°N; Yukon."],
        BBOX[41.67,-141.01,69.8,-59.73]],
    ID["EPSG",9983],
    REMARK["Valid at epoch 1997.0. Hybrid geoid derived from CGG2000 gravimetric geoid fitted to 1926 benchmarks with CGVD28 and NAD83(CSRS)v3 heights. On publication in 2019 of models valid at other epochs, file renamed from ""HT2_0.byn""; no change to file contents."]]

proj4.defs("EPSG:9983","+proj=pipeline +step +proj=axisswap +order=2,1 +step +proj=unitconvert +xy_in=deg +xy_out=rad +step +inv +proj=vgridshift +grids=ca_nrc_HT2_1997.tif +multiplier=1 +step +proj=unitconvert +xy_in=rad +xy_out=deg +step +proj=axisswap +order=2,1");

{
    "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json",
    "type": "Transformation",
    "name": "NAD83(CSRS)v3 to CGVD28 height (1)",
    "source_crs": {
        "type": "GeographicCRS",
        "name": "NAD83(CSRS)v3",
        "datum": {
            "type": "GeodeticReferenceFrame",
            "name": "North American Datum of 1983 (CSRS) version 3",
            "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": 8239
        }
    },
    "target_crs": {
        "type": "VerticalCRS",
        "name": "CGVD28 height",
        "datum": {
            "type": "VerticalReferenceFrame",
            "name": "Canadian Geodetic Vertical Datum of 1928"
        },
        "coordinate_system": {
            "subtype": "vertical",
            "axis": [
                {
                    "name": "Gravity-related height",
                    "abbreviation": "H",
                    "direction": "up",
                    "unit": "metre"
                }
            ]
        },
        "id": {
            "authority": "EPSG",
            "code": 5713
        }
    },
    "method": {
        "name": "Geographic3D to GravityRelatedHeight (NRCan byn)",
        "id": {
            "authority": "EPSG",
            "code": 1060
        }
    },
    "parameters": [
        {
            "name": "Geoid (height correction) model file",
            "value": "HT2_1997.byn",
            "id": {
                "authority": "EPSG",
                "code": 8666
            }
        }
    ],
    "accuracy": "0.05",
    "scope": "Derivation of gravity-related heights from GNSS observations.",
    "area": "Canada - onshore - Alberta; British Columbia; Manitoba south of 57°N; New Brunswick; Northwest Territories south west of a line between 60°N, 110°W and the coast at 132°W; Nova Scotia; Ontario south of 52°N; Prince Edward Island; Quebec - mainland west of 66°W and south of 55°N; Saskatchewan south of 55°N; Yukon.",
    "bbox": {
        "south_latitude": 41.67,
        "west_longitude": -141.01,
        "north_latitude": 69.8,
        "east_longitude": -59.73
    },
    "id": {
        "authority": "EPSG",
        "code": 9983
    },
    "remarks": "Valid at epoch 1997.0. Hybrid geoid derived from CGG2000 gravimetric geoid fitted to 1926 benchmarks with CGVD28 and NAD83(CSRS)v3 heights. On publication in 2019 of models valid at other epochs, file renamed from \"HT2_0.byn\"; no change to file contents."
}

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	<Layer srs="+proj=pipeline +step +proj=axisswap +order=2,1 +step +proj=unitconvert +xy_in=deg +xy_out=rad +step +inv +proj=vgridshift +grids=ca_nrc_HT2_1997.tif +multiplier=1 +step +proj=unitconvert +xy_in=rad +xy_out=deg +step +proj=axisswap +order=2,1">
	</Layer>
</Map>

INSERT into spatial_ref_sys (srid, auth_name, auth_srid, proj4text, srtext) values ( 9983, 'EPSG', 9983, '+proj=pipeline +step +proj=axisswap +order=2,1 +step +proj=unitconvert +xy_in=deg +xy_out=rad +step +inv +proj=vgridshift +grids=ca_nrc_HT2_1997.tif +multiplier=1 +step +proj=unitconvert +xy_in=rad +xy_out=deg +step +proj=axisswap +order=2,1', 'None');