If you were to take a road trip right now between Los Angeles and San Francisco, mile after mile of green rolling hills (such as these in Santa Maria, captured by George Rose) might be enough to convince you that things were back to normal in California after five years of volatile weather and punishing drought.
In fact, although last winter was predicted to be one of the wettest winters in history thanks to the phenomenon of warming Pacific Ocean currents known as El Niño, California as a whole received below-average rainfall. If the supposedly extreme winter of 2015-16 gave...