A group of more than 100 scientists and experts say in a new report that California faces the risk of a massive “superstorm” that could flood a quarter of the state’s homes and cause $300 billion to $400 billion in damage. Researchers point out that the potential scale of destruction in this storm scenario is four or five times the amount of damage that could be wrought by a major earthquake.
It sounds like the plot of an apocalyptic action movie, but scientists with the U.S. Geological Survey warned federal and state emergency officials that California’s geological history shows such “superstorms” have happened in the past, and should be added to the long list of natural disasters to worry about in the Golden State.
The threat of a cataclysmic California storm has been dormant for the past 150 years. Geological Survey director Marcia K. McNutt told the New York Times that a 300-mile stretch of the Central Valley was inundated from 1861-62. The floods were so bad that the state capital had to be moved to San Francisco, and Governor Leland Stanford had to take a rowboat to his own inauguration, the report notes. Even larger storms happened in past centuries, over the dates 212, 440, 603, 1029, 1418, and 1605, according to geological evidence.
The risk is gathering momentum now, scientists say, due to rising temperatures in the atmosphere, which has generally made weather patterns more volatile.
The scientists built a model that showed a storm could last for more than 40 days and dump 10 feet of water on the state. The storm would be goaded on by an “atmospheric river” that would move water “at the same rate as 50 Mississippis discharging water into the Gulf of Mexico,” according to the AP. Winds could reach 125 miles per hour, and landslides could compound the damage, the report notes.
Such a superstorm is hypothetical but not improbable, climate researchers warn. “We think this event happens once every 100 or 200 years or so, which puts it in the same category as our big San Andreas earthquakes,” Geological Survey scientist Lucy Jones said in a press release.
Federal and state emergency management officials convened a conference about emergency preparations for possible superstorms last week.
See the full report HERE!
In the scenario, the storm system forms in the Pacific and slams into the West Coast with hurricane-force winds, hitting Southern California the hardest. After more than a week of ferocious weather, the system stalls for a few days. Another storm brews offshore and this time pummels Northern California. Such a monster storm could unleash as much as 8 feet of rain over three weeks in some areas, said research meteorologist Martin Ralph with the National Oceanic and Atmospheric Administration, who is part of the project.
The New York Times writes:
California faces the risk not just of devastating earthquakes but also of a catastrophic storm that could tear at the coasts, inundate the Central Valley and cause four to five times as much economic damage as a large quake, scientists and emergency planners warn.
The potential for such a storm was described at a conference of federal and California officials that ended Friday. Combining advanced flood mapping and atmospheric projections with data on California’s geologic flood history, over 100 scientists calculated the probable consequences of a “superstorm” carrying tropical moisture from the South Pacific and dropping up to 10 feet of rain across the state.
“Floods are as much a part of our lives in California as earthquakes are,” said Lucy Jones, the chief scientist for the United States Geological Survey’s multi-hazards initiative, adding, “We are probably not going to be able to handle the biggest ones.”
The geological survey estimates that such a storm could cause up to $300 billion in damage. The scientists’ models estimate that almost one-fourth of the houses in California could experience some flood damage from one.
The conference was convened by the geological survey, the Federal Emergency Management Agency and the California Emergency Management Agency to help disaster-response planners draft new strategies to limit the storms’ impact.
Climate scientists have for years noted that the rising temperature of the earth’s atmosphere increases the amount of energy it stores, making more violent and extreme weather events more likely.
Californians have learned to expect earthquakes the way Floridians expect hurricanes. (A minor earthquake, with a preliminary magnitude of 4.1, rattled windows in the southern part of the San Francisco Bay area about a week ago.)
The existing engineering systems that dispose of floodwater are so efficient that the effects of moderate storms often go unnoticed, Dr. Jones said. So while many Californians know whether they live or work close to an earthquake-prone fault and what to do should there be a serious quake, few realize that the state could be hit by storms that at their worst could rival the largest hurricanes that devastate the Gulf Coast and the southeastern Atlantic Seaboard.
Yet vast floods have also been documented, both through tree-ring data and more modern historical records. Marcia K. McNutt, the director of the geological survey, said that 150 years ago, over a few weeks in the winter of 1861-62, enough rain fell to inundate a stretch of the Central Valley 300 miles long and 20 miles wide, from north of Sacramento south to Bakersfield, near the eastern desert.
The storms lasted 45 days, creating lakes in parts of the Mojave Desert and, according to a survey account, “turning the Sacramento Valley into an inland sea, forcing the state capital to be moved from Sacramento to San Francisco for a time, and requiring Gov. Leland Stanford to take a rowboat to his inauguration.”
Just like a major earthquake, a superstorm could be a severe blow to the state’s agriculture and to the water-supply system that now diverts water from the north to Southern California.
Dr. Jones said in an interview that improved satellite imagery available in recent years allowed scientists to clearly identify what they call “atmospheric rivers” — moisture-filled air currents up to 200 miles wide and 2,000 miles long, which flow from tropical regions of the Pacific Ocean to the West Coast.
The West Coast winter weather systems popularly known as the Pineapple Express, air currents carrying moisture from the Hawaiian Islands are just one moderate subset of these rivers, Dr. Jones said. The abbreviation for atmospheric river, A.R., gave the geological survey the root of its name for these major weather events, which they call ARk storms.
WATCH “THE ARK STORM” HERE: