VERTCRS["IGb08",
    VDATUM["IGb08"],
    CS[vertical,1],
        AXIS["ellipsoidal height (h)",up,
            LENGTHUNIT["metre",1]],
    USAGE[
        SCOPE["Not known."],
        AREA["World."],
        BBOX[-90,-180,90,180]],
    ID["ESRI",115871]]