Slide 1 of 31 2:36Now Playing Climate change threatens the survival of California’s iconic piers, including San Diego’s Mount Calavera in Carlsbad is a volcano 3:47 San Diegans hit retailers to return or exchange those gifts that just weren’t right 2:46 San Diegans hit retailers to return or exchange those gifts that just weren’t right San Diegans flock to UTC, Fashion Valley malls to shop for last-minute holiday gifts