Along with the ever-present danger of wildfires and earthquakes, “megadrought” has become a major weather worry in the Western United States. However, a new study has warned that “Megafloods” pose an even greater threat to California.
New research published on Friday shows that climate change is raising the prospect of future floods across California, which could cause the destruction of several cities and the relocation of millions of people.
It predicts that hundreds of miles of California might get buried under feet of rain from an intense storm lasting a whole month. There have been similar relentless storms in the past, long before the region became populated by tens of millions of people.
With the current rate of warming, the study claims that the likelihood of and severity of the next megaflood will increase considerably with each additional degree of warming.
“the storm sequence is bigger in almost every respect,” said Daniel Swain, a climate scientist at UCLA and co-author of the study, in a press statement. Greater amounts of rain are falling, and the rainfall is becoming more intense on an hourly basis.
Megafloods Influenced By Global Warming
In reality, the study discovered that the likelihood of such catastrophic floods is doubled due to climate change.
According to Swain, large-scale floods across the entire state of California have occurred about once every two centuries during the past thousand years, and the contemporary risk of such occurrences is greatly overestimated.
The Great Flood of 1862 in California was up to 300 miles long and 60 miles across, and it occurred long before climate change. The study estimates that a similar flood now would force 5-10 million people to relocate, close down the state’s key freeways for weeks or months at a time, and have a significant economic impact on the state.
This research builds on the “ArkStorm scenario” from 2010, so named for the atmospheric rivers that will feed the biblically massive flood that it predicts. This is the beginning of a plan called ArkStorm 2.0, which will revisit that situation.
Massive California Flood Would Be A $1 Trillion Disaster
An identical flood to the one in 1862 would cost an estimated $1 trillion, according to research conducted by UCLA.
“Even with the current system of reservoirs, levees, and bypasses, parts of cities like Sacramento, Stockton, Fresno, and Los Angeles would be flooded. It would be the costliest catastrophe in human history, valued at $1 trillion “if the statement is to be believed.
Swain noted in the release that Californians could have forgotten about major flooding because of the state’s focus on drought and wildfires. Although California is at risk for devastating wildfires every year, many years go by without any significant flood reports. People tend to forget about it,” he remarked.
According to UCLA, scientists compared two extreme scenarios using new high-resolution weather models and existing climate models: one that would occur roughly once per century in the recent historical climate, and another in the anticipated climate of 2081-2100.
In both cases, atmospheric rivers would feed a prolonged succession of storms lasting at least a month.
What Are Atmospheric Rivers?
Ribbons of water vapor, known as atmospheric rivers, can stretch for thousands of miles, from the tropics to the western United States. They generate enormous rain and snowstorms that can bring floods throughout the West Coast and are anywhere from 250 miles to 375 miles broad.
The National Oceanic and Atmospheric Administration noted that although such occurrences are good for water supplies, they can cause traffic disruptions, deadly mudslides, and extensive property damage.
Warmer, more intense, and more frequent atmospheric rivers are predicted as a result of climate change.
Science Advances is a journal of the American Association for the Advancement of Science and featured Friday’s research.