PROJCS["US National Atlas Equal Area",GEOGCS["Unspecified datum based upon the Clarke 1866 Authalic Sphere",DATUM["D_Sphere_Clarke_1866_Authalic",SPHEROID["Clarke_1866_Authalic_Sphere",6370997,0]],PRIMEM["Greenwich",0],UNIT["Degree",0.017453292519943295]],PROJECTION["Lambert_Azimuthal_Equal_Area"],PARAMETER["latitude_of_origin",45],PARAMETER["central_meridian",-100],PARAMETER["false_easting",0],PARAMETER["false_northing",0],UNIT["Meter",1]]