CA Civ Proc Code Section 1953.06

If an appeal to a reviewing court has been taken in any action or special proceeding in any trial court in which the record has been subsequently lost or destroyed by conflagration or other public calamity and a transcript of such record has been filed in the reviewing court, any person interested in the action or special proceeding may obtain a certified copy of all or any portion of the transcript from the clerk of the reviewing court and may file such certified copy in the office of the clerk of the court from which the appeal was taken. Thereupon the certified copy may be made the basis of any further proceedings or processes in the trial court in such action or special proceeding to all intents and purposes as if the original record were on file.