New Yorker: In 1977, the San Joaquin Valley-the swath of agricultural land that runs through central California-was designated a disaster area. Record-low runoff and scant rainfall had created drought conditions. At the beginning of Christmas week, the weather was normal in Bakersfield, the city at the Valley`s southern end, but in the early hours of December 20th a strong wind began to blow from the Great Basin through the Tehachapi Mountains. Hitting the ground on the downslope, it lofted a cloud of loose...