EPSG:9246

COORDINATEOPERATION["NAD83(CSRS)v6 to CGVD2013(CGG2013) height (1)",
    VERSION["NRC Can CGG2013"],
    SOURCECRS[
        GEOGCRS["NAD83(CSRS)v6",
            DATUM["North American Datum of 1983 (CSRS) version 6",
                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",8251]]],
    TARGETCRS[
        VERTCRS["CGVD2013(CGG2013) height",
            VDATUM["Canadian Geodetic Vertical Datum of 2013 (CGG2013)"],
            CS[vertical,1],
                AXIS["gravity-related height (H)",up,
                    LENGTHUNIT["metre",1]],
            ID["EPSG",6647]]],
    METHOD["Geographic3D to GravityRelatedHeight (NRCan byn)",
        ID["EPSG",1060]],
    PARAMETERFILE["Geoid (height correction) model file","CGG2013n83.byn"],
    OPERATIONACCURACY[0.03],
    USAGE[
        SCOPE["Derivation of gravity-related heights from GNSS observations."],
        AREA["Canada - onshore and offshore - Alberta; British Columbia; Manitoba; New Brunswick; Newfoundland and Labrador; Northwest Territories; Nova Scotia; Nunavut; Ontario; Prince Edward Island; Quebec; Saskatchewan; Yukon."],
        BBOX[38.21,-141.01,86.46,-40.73]],
    ID["EPSG",9246],
    REMARK["Uses CGG2013 model which uses bi-quadratic interpolation; bi-linear interpolation of the grid file will give results agreeing to within 1cm 99.97% of the time. Replaced by CGG2013a model (CT code 9247)."]]

proj4.defs("EPSG:9246","+proj=pipeline +step +proj=axisswap +order=2,1 +step +proj=unitconvert +xy_in=deg +xy_out=rad +step +inv +proj=vgridshift +grids=ca_nrc_CGG2013n83.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)v6 to CGVD2013(CGG2013) height (1)",
    "source_crs": {
        "type": "GeographicCRS",
        "name": "NAD83(CSRS)v6",
        "datum": {
            "type": "GeodeticReferenceFrame",
            "name": "North American Datum of 1983 (CSRS) version 6",
            "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": 8251
        }
    },
    "target_crs": {
        "type": "VerticalCRS",
        "name": "CGVD2013(CGG2013) height",
        "datum": {
            "type": "VerticalReferenceFrame",
            "name": "Canadian Geodetic Vertical Datum of 2013 (CGG2013)"
        },
        "coordinate_system": {
            "subtype": "vertical",
            "axis": [
                {
                    "name": "Gravity-related height",
                    "abbreviation": "H",
                    "direction": "up",
                    "unit": "metre"
                }
            ]
        },
        "id": {
            "authority": "EPSG",
            "code": 6647
        }
    },
    "method": {
        "name": "Geographic3D to GravityRelatedHeight (NRCan byn)",
        "id": {
            "authority": "EPSG",
            "code": 1060
        }
    },
    "parameters": [
        {
            "name": "Geoid (height correction) model file",
            "value": "CGG2013n83.byn",
            "id": {
                "authority": "EPSG",
                "code": 8666
            }
        }
    ],
    "accuracy": "0.03",
    "scope": "Derivation of gravity-related heights from GNSS observations.",
    "area": "Canada - onshore and offshore - Alberta; British Columbia; Manitoba; New Brunswick; Newfoundland and Labrador; Northwest Territories; Nova Scotia; Nunavut; Ontario; Prince Edward Island; Quebec; Saskatchewan; Yukon.",
    "bbox": {
        "south_latitude": 38.21,
        "west_longitude": -141.01,
        "north_latitude": 86.46,
        "east_longitude": -40.73
    },
    "id": {
        "authority": "EPSG",
        "code": 9246
    },
    "remarks": "Uses CGG2013 model which uses bi-quadratic interpolation; bi-linear interpolation of the grid file will give results agreeing to within 1cm 99.97% of the time. Replaced by CGG2013a model (CT code 9247)."
}

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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_CGG2013n83.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 ( 9246, 'EPSG', 9246, '+proj=pipeline +step +proj=axisswap +order=2,1 +step +proj=unitconvert +xy_in=deg +xy_out=rad +step +inv +proj=vgridshift +grids=ca_nrc_CGG2013n83.tif +multiplier=1 +step +proj=unitconvert +xy_in=rad +xy_out=deg +step +proj=axisswap +order=2,1', 'None');