def gpmset_metadata() -> dict:
    """
    Return a bunch of metadata (description, units, long_name, etc.) for the
    gpmset.

    Returns:
    ========
    metadata: dict
    """
    metadata = {
        "overpass_time": {
            "description": "GPM overpass time at the closest from ground radar site"
        },
        "x": {
            "units": "m",
            "description": "x-axis parallax corrected coordinates in relation to ground radar.",
        },
        "y": {
            "units": "m",
            "description": "y-axis parallax corrected coordinates in relation to ground radar.",
        },
        "z": {
            "units": "m",
            "description": "z-axis parallax corrected coordinates in relation to ground radar.",
        },
        "precip_in_gr_domain": {
            "units": "1",
            "description": "Satellite data-columns with precipitation inside the ground radar scope.",
        },
        "range_from_gr": {
            "units": "m",
            "description": "Range from satellite bins in relation to ground radar",
        },
        "elev_from_gr": {
            "units": "degrees",
            "description": "Elevation from satellite bins in relation to ground radar",
        },
        "reflectivity_grband": {"units": "dBZ"},
    }
    return metadata