According to a recent study by Science Advances, the likelihood of a catastrophic flood in California occurring within the next 40 years has already increased by double as a result of climate change. And according to scientists, it would be a whole new experience for everyone alive today.
A megaflood is “an extremely severe flood event across a broad territory that has the potential to bring catastrophic repercussions to civilization in the places affected,” according to Daniel Swain, a UCLA climate scientist and researcher who was engaged in the study. In comparison to the 1,000-year flash floods that occurred this summer in the St. Louis region and Kentucky, he claimed that a megaflood would affect a considerably larger area, such as the entire state of California.
According to experts, these enormous floods, which would convert California’s lowlands into a “huge inland sea,” may have occurred only once in a lifetime in the state. However, according to experts, the chance of these catastrophic calamities is rising due to climate change, making them more likely to happen every 25 to 50 years.
This summer, flash floods were reported often in Eastern Kentucky, St. Louis, and even Death Valley National Park in California. Flash floods are caused by severe rain events that are accelerated by climate change.
However, climate change is upping the ante, and millions of people might be affected. Although California is naturally vulnerable to these atmospheric river floods and significant floods from them, have occurred previously,
As demonstrated in this animation, the study claimed that atmospheric rivers might become consecutive for extended periods. This loop was created by one of the study’s authors, Xingying Huang, and it shows how water vapor moves through the air and how much precipitation might accumulate at various points throughout the 30-day scenario.
According to the authors of the study, California’s Central Valley, which includes Sacramento, Fresno, and Bakersfield, will see the most destruction. According to the US Geological Survey, the Central Valley, which is about the same size as Massachusetts and Vermont put together, produces 25% of the country’s food.
According to the study, a flood the size of this valley may be the most expensive geophysical disaster to date, resulting in losses of up to $1 trillion and wreaking havoc on the state’s lowland regions, including Los Angeles and Orange counties.
As of this now, Hurricane Katrina is the most expensive disaster in US history, costing more than five times as much.
The repercussions of a potential megaflood event in California are being examined in this study, the first of three parts. In two to three years, the following two phases should be available.
The most recent flooding experience in California
After a long period of drought that left the West parched, the Golden State was drenched over 150 years ago by a powerful sequence of atmospheric rivers, generating one of the most extraordinary floods in history. In a matter of minutes, entire towns were destroyed.
The San Joaquin and Sacramento valleys were turned into a “temporary but massive inland sea” by a historic megaflood that occurred in the winter of 1861–1862. Infrastructure, farms, and villages were destroyed by up to 30 feet of water for weeks.
It took months for the debris-filled water to reach Sacramento, the newly established state capital.
In the Sierra Nevada, a nearly 15-foot snowfall in December 1861 set off the tragedy. Then, 43 days later, a warm rain that fell in bursts from atmospheric rivers flooded the valleys and down the mountainside.
A quarter of California’s cattle herd starved to death or drowned, 4,000 people perished, and one in eight homes were destroyed by flooding. One-third of the state’s property was also destroyed.
A state-wide bankruptcy was also brought on by the destruction of one-fourth of California’s economy.
According to Swain, an even worse and more frequent megaflood will occur again.
According to Swain, many of today’s megacities, many of which have millions of inhabitants, were constructed immediately on top of the remains of historic floods, placing an even greater number of people at risk.
In 1862, California had a population of about 500,000. There are currently approximately 39 million people living in the state.