0
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 topsoil and mustard-colored dust into the sky.