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for people who care about the West

Chilling forecast

 

We might have to say goodbye to California apples, walnuts, pistachios, cherries and other stone fruit over the next century, according to a recent report from scientists at the University of California-Davis. Between 1950 and 2000, the winter chill hours essential for fruit and nut tree growth -- defined by temperatures between 32 and 45 degrees Fahrenheit -- dropped by 30 percent in parts of the state’s Central Valley, the source of nearly half of the United States’ fruit and nut production. And winter chill will likely decline even more as the planet continues to warm. Scientists used 50 years of weather data to create two climate models, which respectively predict 50 and 80 percent decreases in winter chill by 2099 from the 1950 baseline.