EPSG:10590

proj4.defs("EPSG:10590","+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(HTv2.0) height (1)",
    "source_crs": {
        "type": "GeographicCRS",
        "name": "NAD83(CSRS)v2",
        "datum": {
            "type": "GeodeticReferenceFrame",
            "name": "North American Datum of 1983 (CSRS) version 2",
            "anchor_epoch": 1997,
            "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(HTv2.0) height",
        "datum": {
            "type": "VerticalReferenceFrame",
            "name": "Canadian Geodetic Vertical Datum of 1928 (Height Transformation version 2.0)",
            "anchor_epoch": 1997
        },
        "coordinate_system": {
            "subtype": "vertical",
            "axis": [
                {
                    "name": "Gravity-related height",
                    "abbreviation": "H",
                    "direction": "up",
                    "unit": "metre"
                }
            ]
        },
        "id": {
            "authority": "EPSG",
            "code": 10588
        }
    },
    "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": "0.01",
    "scope": "Derivation of approximate gravity-related heights from GNSS observations.",
    "area": "Canada - onshore and offshore between 41°N and 84°N and west of 48°W - Alberta; British Columbia; Manitoba; New Brunswick; Newfoundland and Labrador; Northwest Territories; Nova Scotia; Nunavut; Ontario; Prince Edward Island; Quebec; Saskatchewan; Yukon.",
    "bbox": {
        "south_latitude": 41,
        "west_longitude": -141.01,
        "north_latitude": 84,
        "east_longitude": -48
    },
    "id": {
        "authority": "EPSG",
        "code": 10590
    },
    "remarks": "Hybrid geoid model. Valid at epoch 1997.0. A provisional grid was derived through NAD83(CSRS98) = NAD83(CSRS)v2 and used in HT1 software. This grid is an update used in HT2 software, derived through NAD83(CSRS)v3, CRS code 8239."
}

<?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=ca_nrc_HT2_1997.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=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 ( 10590, 'EPSG', 10590, '+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');