SAN DIEGO — All San Diego County government offices will be closed Friday, Dec. 31, in observance of the New Year’s Day holiday. According to county officials, libraries will be closed Dec. 31 and Saturday, Jan. 1, although county parks will be open. The Department of Parks and Recreation reservation phone line is closed through Jan. 2, but customers will still be able to make online reservations. The county’s three animal shelters in Carlsbad, San Diego and Bonita will be closed Friday, but will reopen Saturday. Essential services, like law enforcement, will not be affected by the holiday. County offices and libraries will resume normal business hours on Monday, Jan. 3.