A satellite photo shows California’s Central Valley socked in with thick, white tule fog. Tule fog is thought to arise from wetlands full of tules, Schoenoplectus acutus, a reed or rush common to marshes in California. To achieve high yields, fruit trees need the sustained periods with temperatures below about 44 degrees Fahrenheit during prolonged periods of tule fog. They hypothesize that the decrease in winter fog is occurring along with and contributing to a reduction in winter chill. But if population growth and urbanization continue in the Central Valley, the reduction in air pollution may not last, LaDochy warns.

Source: Los Angeles Times January 11, 2020 23:15 UTC