Between 2011 and 2017, California suffered through one of the worst droughts in its history. After the drought broke last year in what would be California’s wettest winter in a century, extreme flooding caused severe damage and killed several people. In a study recently published in the journal Nature Climate Change, researchers predict that similar patterns of polarized weather will continue to define California’s climate well into the 21st century, particularly if greenhouse gas emissions are not immediately and significantly reduced. If emissions continue to grow until 2100, the drastic wet-dry weather patterns could double in frequency, wreaking havoc in the state.
California is not unfamiliar with bouts of strong drought and flooding. In 1862, what is known as the Great Flood devastated California in a weather event that has not be repeated since. Much of the state has a Mediterranean climate, which is conducive to dry summers, wet winters, and powerful shifts between those two extremes. However, as with much of the extreme weather expected from climate change, the frequency and intensity of such weather events are increasing. As the weather becomes more destructive, the authors predict that California could face serious challenges, particularly in water storage/access and flood control.
In order to prepare for a more hostile climate, California must upgrade its infrastructure. “Few of the dams, levees and canals that currently protect millions living in California’s flood plains and facilitate the movement of water from Sierra Nevada watersheds to coastal cities have been tested by a deluge as severe” as the Great Flood of 1862, wrote the researchers. On the other side of the world, Europe faces a drier future, with another study predicting that the percentage of drought-prone area will double if global average temperatures continue to rise beyond a 3 degrees Celsius increase. Even if the goals of the Paris agreement are met, which at the moment seems doubtful, Africa is still expected to endure potentially destabilizing extreme weather as a result of foregone climate change.