EPSG:9125

COORDINATEOPERATION["ITRF2008 to CGVD2013a(2010) height (2)",
    VERSION["NRC Can CGG2013a"],
    SOURCECRS[
        GEOGCRS["ITRF2008",
            DYNAMIC[
                FRAMEEPOCH[2005]],
            DATUM["International Terrestrial Reference Frame 2008",
                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",7911]]],
    TARGETCRS[
        VERTCRS["CGVD2013a(2010) height",
            VDATUM["Canadian Geodetic Vertical Datum of 2013 (CGG2013a) epoch 2010"],
            CS[vertical,1],
                AXIS["gravity-related height (H)",up,
                    LENGTHUNIT["metre",1]],
            ID["EPSG",9245]]],
    METHOD["Geographic3D to GravityRelatedHeight (NRCan byn)",
        ID["EPSG",1060]],
    PARAMETERFILE["Geoid (height correction) model file","CGG2013ai08.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",9125],
    REMARK["Replaces CT code 9124. Uses CGG2013a model at epoch 2010.0. In ITRF the CGVD2013 geoid velocity is not zero so CGVD2013 heights derived through ITRF change with respect to those derived through NAD83(CSRS). CGRSC recommends using NAD83(CSRS) (code 9247)."]]

proj4.defs("EPSG:9125","+proj=pipeline +step +proj=axisswap +order=2,1 +step +proj=unitconvert +xy_in=deg +xy_out=rad +step +inv +proj=vgridshift +grids=ca_nrc_CGG2013ai08.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": "ITRF2008 to CGVD2013a(2010) height (2)",
    "source_crs": {
        "type": "GeographicCRS",
        "name": "ITRF2008",
        "datum": {
            "type": "DynamicGeodeticReferenceFrame",
            "name": "International Terrestrial Reference Frame 2008",
            "frame_reference_epoch": 2005,
            "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": 7911
        }
    },
    "target_crs": {
        "type": "VerticalCRS",
        "name": "CGVD2013a(2010) height",
        "datum": {
            "type": "VerticalReferenceFrame",
            "name": "Canadian Geodetic Vertical Datum of 2013 (CGG2013a) epoch 2010"
        },
        "coordinate_system": {
            "subtype": "vertical",
            "axis": [
                {
                    "name": "Gravity-related height",
                    "abbreviation": "H",
                    "direction": "up",
                    "unit": "metre"
                }
            ]
        },
        "id": {
            "authority": "EPSG",
            "code": 9245
        }
    },
    "method": {
        "name": "Geographic3D to GravityRelatedHeight (NRCan byn)",
        "id": {
            "authority": "EPSG",
            "code": 1060
        }
    },
    "parameters": [
        {
            "name": "Geoid (height correction) model file",
            "value": "CGG2013ai08.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": 9125
    },
    "remarks": "Replaces CT code 9124. Uses CGG2013a model at epoch 2010.0. In ITRF the CGVD2013 geoid velocity is not zero so CGVD2013 heights derived through ITRF change with respect to those derived through NAD83(CSRS). CGRSC recommends using NAD83(CSRS) (code 9247)."
}

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	</Layer>
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INSERT into spatial_ref_sys (srid, auth_name, auth_srid, proj4text, srtext) values ( 9125, 'EPSG', 9125, '+proj=pipeline +step +proj=axisswap +order=2,1 +step +proj=unitconvert +xy_in=deg +xy_out=rad +step +inv +proj=vgridshift +grids=ca_nrc_CGG2013ai08.tif +multiplier=1 +step +proj=unitconvert +xy_in=rad +xy_out=deg +step +proj=axisswap +order=2,1', 'None');