California may see a 54 percent increase in rainfall variability by the end of this century, according to new research from the lab of Assistant Professor Da Yang, a 2019 Packard Fellow and atmospheric scientist with the University of California, Davis. Writing in the journal Nature Climate Change, Yang and his co-authors predict the entire West Coast will experience greater month-to-month fluctuations in extremely dry and wet weather, especially in California. The lead author is Wenyu Zhou, a postdoctoral researcher in the Lawrence Berkeley National Laboratory where Yang has a dual appointment.

The study explores the Madden-Julian oscillation (MJO), an atmospheric phenomenon that influences rainfall in the tropics and can trigger everything from cyclones over the Indian Ocean to heatwaves, droughts and flooding in the United States.