The present four-year California drought is not novel — even if President Barack Obama and California Gov. Jerry Brown have blamed it on man-made climate change.
According to the National Oceanic and Atmospheric Administration, California droughts are both age-old and common. Predictable California dry spells — like those of 1929-34, 1976-77 and 1987-92 — more likely result from poorly understood but temporary changes in atmospheric pressures and ocean temperatures.
What is new is that the state has never had 40 million residents during a drought — well over 10 million more than during the last dry spell in the early 1990s. Much of the growth is due to massive and recent immigration.