Will California experience a megaflood that might submerge cities and displace millions of people? According to U.S. scientists, the question is when, not if.

According to a recent study, the likelihood of that megaflood in the ensuing forty years has doubled as a result of human-caused global warming. "We find that climate change has already increased the risk of a megaflood scenario in California, but that future climate warming will likely bring about even sharper risk increases,"  the study warns.

Researchers from the University of California, Los Angeles combined climate and high-resolution weather models to analyze two separate scenarios – the present danger, and a future danger where risks are amplified by the climate crisis, and found with a high-emissions trajectory, the annual likelihood of a 200-year-event would increase by 683 percent by the year 2060, according to The Guardian. 

That scenario has been depicted as unprecedented calamity by the New York Times. "Communities might be ravaged beyond resettling. None of the state's major industries, from tech and Hollywood to farming and oil, will be untouched," it said in an article.

CNN reported that a similar disaster happened over 150 years ago, in the winter of 1861-1862, when a strong series of atmospheric rivers drenched the Golden State, causing one of the most exceptional floods in history following a dry spell that had left the West parched for decades. Communities were demolished in minutes.

By that time, only about 500,000 people lived in the state. Now that population has grown to over 39 million, which means that the catastrophic damage to life and property is expected to increase enormously if a flood of the same scale hits.

For California, a state located on U.S. west coast, the predominant focus is drought and wildfires. The state is currently still reeling from a historical drought. Bloomberg reports that California Governor Gavin Newsom on Thursday released a new plan designed to boost water supplies in the face of worsening droughts brought on by climate change.

Now scientists are worried if the state will be prepared in the face of a hypothetical megaflood.

The study was published in the peer-reviewed journal Science Advances, a publication of the American Association for the Advancement of Science. 

(Cover via VCG)

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