EPSG:9984

COORDINATEOPERATION["NAD83(CSRS)v2 to CGVD28 height (1)",
    VERSION["NRC-Can CGG2000 1997"],
    SOURCECRS[
        GEOGCRS["NAD83(CSRS)v2",
            DATUM["North American Datum of 1983 (CSRS) version 2",
                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",8235]]],
    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",9984],
    REMARK["Valid at epoch 1997.0. Hybrid geoid model. A provisional grid was derived through NAD83(CSRS98) (= NAD83(CSRS)v2) and used HT1 software. This grid is an update derived through NAD83(CSRS)v3, see CT code 9983. It is used in HT2 software."]]

proj4.defs("EPSG:9984","+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)v2 to CGVD28 height (1)",
    "source_crs": {
        "type": "GeographicCRS",
        "name": "NAD83(CSRS)v2",
        "datum": {
            "type": "GeodeticReferenceFrame",
            "name": "North American Datum of 1983 (CSRS) version 2",
            "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": 8235
        }
    },
    "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": 9984
    },
    "remarks": "Valid at epoch 1997.0. Hybrid geoid model. A provisional grid was derived through NAD83(CSRS98) (= NAD83(CSRS)v2) and used HT1 software. This grid is an update derived through NAD83(CSRS)v3, see CT code 9983. It is used in HT2 software."
}

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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 ( 9984, 'EPSG', 9984, '+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');