What authority does this court have to remand an action?

Even apart from the authority granted by the in forma pauperis statute, this court must remand the action once it becomes apparent that it lacks subject matter jurisdiction. 28 U.S.C. 1447 ("[i]f at any time before final judgment it appears that the district court lacks subject matter jurisdiction, the case shall be remanded"); California ex rel. Lockyer v. Dynegy, Inc., 375 F.3d 831, 838, as amended, 387 F.3d 966 (9th Cir. 2004) ("[i]f the district court at any time determines that it lacks jurisdiction over the removed action, it must remedy the improvident grant of removal by remanding the action to state court"), cert. denied, 544 U.S. 974 (2005).