Polar bears aren’t the only ones in trouble from the Arctic’s melting ice. A new study by Bay Area scientists concludes that Californians could face reduced rainfall — and worse droughts — by the continuing loss of sea ice. Their computer analyses show a 10 to 15 percent average decrease in California’s rainfall in the coming decades. The culprit, scientists now believe, is a link between the melting ice and the buildup of massive high pressure systems that park off the California coast and block Pacific storms.