The ARkStorm: California's coming great deluge

By: Dr. Jeff Masters , 4:04 PM GMT on January 28, 2011

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For thirty days and thirty nights the rain fell in unending torrents. By the end of the biblical deluge, rivers of water ten feet deep flowed through the streets of Sacramento, and an astounding 29.28 inches of rain had fallen on San Francisco. According to wunderground's weather historian, Christopher C. Burt, in the Sierras, the moist flow of air from Hawaii--often called an "atmospheric river" or the "Pineapple Express"--hit the steeply sloping mountainsides and rose upwards. The air expanded and cooled, causing truly prodigious rains, with the mining town of Sonora receiving 8.5 feet of rain over a 2-month period. The resulting floods inundated California's Central Valley with a lake 300 miles long and 20 miles wide.

The above event occurred in January 1862, and similar extreme rain events have deluged in California seven times in the past 2,000 years--about once every 300 years. Great storms like the flood of 1862 will happen again. If the planet continues to warm, as expected, the odds of such an event will at least double by 2100, due to the extra moisture increased evaporation from the oceans will add to the air. A group of scientists, emergency managers, and policy makers gathered in Sacramento, California earlier this month to discuss how the state might respond to a repeat of the 1862 rain event--the ARkStorm Scenario. The "AR" stands for "Atmospheric River", the "k" for 1,000 (like a 1-in-1000 year event), and of course "ARkStorm" is meant to summon visions of biblical-scale deluge, similar to the great flood of 1862. The team's final report envisions the most expensive disaster in world history, with direct damages and loss of economic activity amounting to $725 billion.

"Atmospheric Rivers" was a term coined in the 1990s to describe plumes of moisture that ride up out of the subtropics into the mid-latitudes along the axis of a cold front. Traditional water vapor satellite imagery does not show these plumes very well, and it was only when microwave satellite imagery from polar orbiting satellites became available in the late 1990s that the full importance of these Atmospheric Rivers came to be revealed. Atmospheric Rivers account for a significant portion of California's cold season rainfall and snowfall, and an entire session was devoted to them at the December 2010 American Geophysical Union (AGU) meeting in San Francisco, the world's largest Earth Science meeting.


Figure 1. The total amount of rainfall one could get if all the moisture in the air were condensed and fell out as rain is called the Total Precipitable Water (TPW). Here, TPW values from microwave satellite measurements are plotted, and show a plume of very moist air connecting the subtropics near Hawaii with Southern California. TPW vales in excess of 20 mm (about 0.8 inches, blue and warmer colors) are "Atmospheric Rivers", and are often associated with heavy rainfall events capable of causing flooding. This Atmospheric River occurred on December 21, 2010, and brought very heavy flooding rains to Southern California. Image credit: University of Wisconsin CIMSS.

California's Delta Region levees at high risk of failure
Much of Central California's water supply and agricultural areas are protected by an antiquated and poorly maintained set of levees along the Sacramento and San Joaquin Rivers that are in serious danger of failure during an extreme flood or major earthquake. The 1,600 miles of levees protect 500,000 people, 2 million acres of farmland, and structures worth $47 billion. Of particular concern is the delta at the confluence of California's Sacramento and San Joaquin rivers, about 80 miles inland from San Francisco Bay. The Delta Region receives runoff from more than 40% of California, and is the hub of California's water supply system, supplying water to 25 million people and 3 million acres of farmland. Key transportation and communication lines cross the region. The Delta Region is home to dozens of islands with highly productive farms that have subsided to elevations as much as 25 feet below sea level. Jeffrey Mount, director of the Center for Integrated Watershed Science and Management at the University of California at Davis, said in a recent interview with MSNBC, "The chances of a catastrophic flood occurring in the Sacramento-San Joaquin Delta sometime in the next 50 years are about two out of three." He called Sacramento, which is only protected to a 1-in-80 year flood by its levees, "the most at-risk large metropolitan area in the country, with less than half the protection that New Orleans had. It is at extreme risk due to levee failure and subsidence."" The most serious catastrophe for the levees in the Delta Region would be a major earthquake occurring during the dry season. Such a quake would allow salt water to intrude from San Francisco Bay, shutting off the fresh water supply for millions of Californians for months. Collapse of the levees during the wet season would be less devastating, as water pressure from the relatively high flow rates of the Sacramento and San Joaquin Rivers would keep salt water from intruding into the Delta Region. There are no good solutions to California's Delta Region water vulnerabilities, but a new $10 billion dollar canal that would route fresh water around the region is being proposed as a possible way Califoria could avoid losing its fresh water supply if a catatrophic failure of the Delta Region levees allowed salt water intrusion to occur.

A 2009 study by the California Department of Water Resources concluded:

The Delta Region as it exists today is unsustainable. Seismic risk, high water conditions, sea level rise and land subsidence threaten levee integrity. A seismic event is the single greatest risk to levee integrity in the Delta Region. If a major earthquake occurs, levees would fail and as many as 20 islands could be flooded simultaneously. This would result in economic costs and impacts of $15 billion or more. While earthquakes pose the greatest risk to Delta Region levees, winter storms and related high water conditions are the most common cause of levee failures in the region. Under business-as-usual practices, high water conditions could cause about 140 levee failures in the Delta over the next 100 years. Multiple island failures caused by high water would but could still be extensive and could cause approximately $8 billion or more in economic costs and impacts. Dry-weather levee failures [also called sunny-day events] unrelated to earthquakes, such as from slumping or seepage, will continue to occur in the Delta about once every seven years. Costs to repair a single island flooded as the result of a dry-weather levee failure are expected to exceed $50 million. The risk of flooding in the Delta Region will only increase with time if current management practices are not changed. By the year 2100, Delta levee failure risks due to high water conditions will increase by 800 percent. The risk of levee failure from a major earthquake is projected to increase by 93 percent during the same period.


The ARkStorm scenario and Great Flood of 1862 are discussed in much more detail by weather historian Christopher C. Burt in his latest post.


Figure 2. Levee failure on the Upper Jones Tract in the Delta Region on June 4, 2004. Image credit: California Department of Water Resources. A 1997 flood in the Delta Region did $510 million damage, damaged or destroyed 32,000 homes and businesses, and left 120,000 homeless.

Wilma pounding New Zealand; Australia eyes two potential new tropical cyclones
With February nearly upon us, the traditional peak of the Southern Hemisphere tropical cyclone season is here. Activity has picked up markedly this week, with the formation of the year's first two Category 4 tropical cyclones, Tropical Cyclone Wilma and Tropical Cyclone Bianca. Wilma passed over American Samoa as a strong tropical storm, and hit Tonga as a Category 3 storm, causing substantial damage to the islands, but no deaths or injuries. Wilma is currently pounding New Zealand's North Island with heavy rains and strong winds, and is the strongest tropical cyclone to affect that country in fourteen years, according to weatherwatch.co.nz. Tropical Cyclone Bianca is expected to skirt the west coast of Australia over the next few days and rapidly weaken, but could bring heavy rains to the coast near Perth when it makes landfall on Sunday as a tropical storm. Of much greater concern for Australia are two potential tropical cyclones that could hit the flood-ravaged state of Queensland next week. Both the European Center and GFS models predict that the remains of Tropical Cyclone Anthony will regenerate into a tropical storm and hit Queensland early next week. A second and potentially more powerful storm is forecast by the European model to form next week in the islands to the east of Australia, and threaten Queensland at the end of the week. The GFS model has backed off on its prediction of such a storm forming. If the cyclone were to form, it would be a serious blow for Queensland, which is struggling to recover from record floods. As reported in the latest Bureau of Meteorology climate statement and flood summary, the past four months (September - December) have been the rainiest such period in Queensland's history, and the resulting flooding disaster has been Australia's most expensive natural disaster in history.


Figure 3. Tropical Cyclone Bianca, the globe's second major tropical cyclone of 2011, as seen at 06:30 GMT on January 28, 2011 by NASA's Aqua satellite. Biana is expected to rapidly weaken and hit the Australian coast near Perth as a tropical storm on Sunday. Image credit: NASA.

Have a great weekend, and I'll be back Monday with a new post.

Jeff Masters

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McNightRider meet SSI...... you're a busy guy, lately, what with all the new names and all....

have fun!

:)
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Quoting NRAamy:
53. NRAamy 11:00 AM PST on January 28, 2011

does no one want to discuss Dr. Masters' topic today? No one cares about Calif?


I've mentioned several times that I'm a native Californian. I was born in L.A., I spent my early childhood in Hollywood, then lived in Orange County for a number of years before moving away. I was back in Santa Barbara some years later, then Ojai. So I've seen a lot of Pineapple Express events, including a couple of significant ones, the largest being the January, 2005, one that caused so much flooding after dropping 28" of rain in three days at a forest service station a few miles from where I lived. (There was also a long event when I was a kid--or rather several distinct events that blurred into one--that lasted for two weeks.)

I believe the ARk / Noachian storm scenario will happen again some day. I'm not at all sure California and the nation are ready for that to happen, though. Besides, if/when it does happen, it may end up being just another destructive event of many brought on by rapid climate change--or it could be the straw that breaks the camel's back. :-\
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Quoting NRAamy:
53. NRAamy 11:00 AM PST on January 28, 2011

does no one want to discuss Dr. Masters' topic today? No one cares about Calif?

I couldn't imagine seeing something like that on the news.I would freak!!
Member Since: August 14, 2010 Posts: 10 Comments: 17825
53. NRAamy 11:00 AM PST on January 28, 2011

does no one want to discuss Dr. Masters' topic today? No one cares about Calif?

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Quoting washingtonian115:
God put us here for a reason.He trusted us with the planet.

If, as some believe, any one of the 2,800 or so known deities entrusted us humans with this planet, she, he, or it must be very disappointed in us right about now, I would think.
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Neap.... you left out the very serious discussion on topic....
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Quoting KEEPEROFTHEGATE:
well i see we are having another one of those pissing contests again

You mean the 120 comments from earlier today where the same five people tried to out-joke each other about space aliens, undocumented workers, and the stupidity of GW-believing scientists? Is that the contest you're talking about? I agree: it was an ugly thing to see, and it really lowered the level of discourse here.
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Member Since: July 15, 2006 Posts: 178 Comments: 56141
138. DEKRE
Quoting Neapolitan:


Whatever they did, as I said, they had the excuse of not knowing any better. Nobody has that excuse today.
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I had a alligator fried Po-boy fer Lunch today.

Extra tabasco.


And a Fresca.

Member Since: July 3, 2005 Posts: 428 Comments: 129902
131. washingtonian115 1:33 PM PST on January 28, 2011

Hollllllllld up!!!.God put us here for a reason.He trusted us with the planet.If earth is destroyed where else do you all think we'll go?.Huh?.I won't say further more before I end up going berserk on some body up in here.



not to worry.... the ancient aliens will come back and save the day....
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Quoting DEKRE:
Sorry, they did - check with your archaeologists. Not by the millions as the whites later, but still be the many hundreds with one go. Far more than they could use.
Link

They did kill them en masse--I'm not disputing that--but they never killed more that they could use, nor did they kill for "fun". From your own link, note that every bit of the animal was used, and that any excess was used for barter. It's true that some Native Americans, once they gained access to rifles and horses, began profiting from the sale of buffalo, but, again, they never slaughtered just for the sake of slaughter.
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well i see we are having another one of those pissing contests again
Member Since: July 15, 2006 Posts: 178 Comments: 56141
Hollllllllld up!!!.God put us here for a reason.He trusted us with the planet.If earth is destroyed where else do you all think we'll go?.Huh?.I won't say further more before I end up going berserk on some body up in here.
Member Since: August 14, 2010 Posts: 10 Comments: 17825
130. DEKRE
Quoting Neapolitan:

They never killed more than they needed. Never. It was the Europeans who invaded the landscape and started brainlessly shooting them just for the "sport" of it.


Sorry, they did - check with your archaeologists. Not by the millions as the whites later, but still be the many hundreds with one go. Far more than they could use.
Link
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Quoting Jedkins01:

Nahhh just some of us would rather enjoy the earth, rather than worship it in fear like its a god.

If there are really two extremes as you say--that is, people either worship the earth or "enjoy" it by decimating it--I'd much rather be in the former group. And if there were some creator or god somewhere, I believe she, he, or it would be aligned with the "tree-huggers", not the destroyers of earth.
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128. DEKRE
Quoting Jedkins01:


No, they did not cause "mass killings of bison". ... You might wanna educate yourself a little better.


Oh yes, they did - by driving whole herds over cliffs. The reason it didn't make much difference was that there were not enough indians

As far as education is concerned - no american should talk about that, especially if he isn't dry behind the ears yet
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Quoting Surfcropper:


you can't call out weather people anymore. when they're wrong they just say "oh, well, the La Nina this and El Nino that was more/less this year, blah blah blah"..as if that's justification for being in a business of trying to lasso something totally random
That's true to.He made his predictions based off of the La nina.But this La nina has been .....weired.It's behaving very indifferent.
Member Since: August 14, 2010 Posts: 10 Comments: 17825
Quoting DEKRE:
By the way, the Native American Culture....

They were actually quite destructive (eg mass killings of bisons). However, they had the excuse of not knowing better as compared to not wanting to know better

They never killed more than they needed. Never. It was the Europeans who invaded the landscape and started brainlessly shooting them just for the "sport" of it. Proof, again, that we should never have been entrusted with the planet; we really are a disease, a blight, a pox. And many of today's remarks on this blog further validate that proof.

Quoting goosegirl1:
We should all be as good custodians of the earth as our native ancestors- there would be no AGW argument going on here if we had.


I'd say you pretty much hit the nail on the head there.
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Quoting Jedkins01:


Nahhh just some of us would rather enjoy the earth, rather than worship it in fear like its a god. Nice try though :)


I'd like to see you last a day on a wilderness survival trip with me and my friends.

If Charles Darwin is right about survival of the fittest, than tree huggers will be a passing phase :)


Wow, such bigotry today.

American Natives did not bring about the near-extinction of the bison, that was the Europeans mass-killing them from trains for a plate full of tongues and a trophy for the den.

Terms such as "red-neck" and "tree hugger" show a shocking lack of compassion and common sense. We should all be as good custodians of the earth as our native ancestors- there would be no AGW argument going on here if we had.
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Quoting JFLORIDA:
Sad the people that hate the earth and environment so much in here. I wish they were not quoted so freely. I don't think that is funny.


Nahhh just some of us would rather enjoy the earth, rather than worship it in fear like its a god. Nice try though :)


I'd like to see you last a day on a wilderness survival trip with me and my friends.

If Charles Darwin is right about survival of the fittest, than tree huggers will be a passing phase :)
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Quoting DEKRE:
By the way, the Native American Culture....

They were actually quite destructive (eg mass killings of bisons). However, they had the excuse of not knowing better as compared to not wanting to know better


No, they did not cause "mass killings of bison". White industrialists did that in an attempt to starve the Native Americans. You might wanna educate yourself a little better.

The Native Americans used bison as a food source, as well as for making tools and many other things. They pretty much had living off the land done the way it was meant to be.
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More snow coming to my area Saturday,and the middel of next week.Yeah I getting my wish!!!.When our local weather man said that we were going to have a warm winter,well...let's just say he's eating crow right now.As for snow totals he predicted anywhere from 12-14 inches.I hope he eats crow for the snow totals as well.
Member Since: August 14, 2010 Posts: 10 Comments: 17825
117. DEKRE
By the way, the Native American Culture....

They were actually quite destructive (eg mass killings of bisons). However, they had the excuse of not knowing better as compared to not wanting to know better
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time for lunch....
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By the way, the Native American Culture that tree huggers uphold so well. Yeah too bad they are like us evil "rednecks" their way of life was hunting and fishing, providing for their family. Yeah, they loved their wilderness, like me, but at they didn't uphold it as being above human life.

I personally could get along with traditional Native American living, as for the tree huggers, well they might educate themselves a little better :)
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111. DEKRE
Quoting Jedkins01:


If those smelts are any good, remind me to catch a few, if they are going extinct, I might as well have a taste of the species first :)


You better stick to BigMacs
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Quoting NRAamy:
The robots almost always win

We need to call the ancient aliens back.... they could fix the levees...

Now, that's tempting fate Amy. Plus do you really want ManBearPig in the equation?
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Quoting Surfcropper:
Do you think its a good investment to buy cases of napa valley wine (2010-2005) if a disaster strikes the Sacramento delta? Talk about rarity in the years after.

Better yet, get a smelt taxidermied inside a 2008 Sutter Home jug and but a plaque under it reading: "Yup."



If those smelts are any good, remind me to catch a few, if they are going extinct, I might as well have a taste of the species first :)
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108. DEKRE
Quoting Jedkins01:


Yeah but we all know that saving that random fish species is more important than improving human condition in California, geeze get on board! Its called progressing beyond the old ignorant ways :)


See 101
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107. DEKRE
Quoting Orcasystems:
You build a city below sea level.. and then scream blue murder about incompetence when it floods... go figure?



Originally, New Orleans was above sea level, but on land resembling a sponge. Then they took the water out of this sponge and it just collapsed.
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Quoting Surfcropper:
Say what you want about Louisianna...they didn't go bankrupt trying to make fish sex more prevalant.


Yeah but we all know that saving that random fish species is more important than improving human condition in California, geeze get on board! Its called progressing beyond the old ignorant ways :)
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Quoting Orcasystems:


I have always been amazed when People are surprised when "mother nature" wins. NOLA is a prime example.. and so is Holland & the Sacramento valley.

We seem to be under the impression that we can do what we wish where we wish... yet are astounded when it fails.


You build a city below sea level.. and then scream blue murder about incompetence when it floods... go figure?

How much energy is in a Hurricane... or the Pineapple Express when it is really running.. can we even fathom that kind of power.. yet we figure we can tame it with steel and cement?

Doomed to failure every time.. its just a matter of when.. not if.




the arrogance of man is truly scary sometimes, sadly to embrace vanity and arrogance is becoming a trend in recent years. Embracing what is already stubborn to remove is a recipe for disaster.
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104. DEKRE
Quoting NRAamy:
You have to be very stupid to have a golf lawn in the middle of a desert.

you callin' Bob Hope stupid?! Now that's just plain un-American....

I agree


Besides, it is a crime what they do to this beautiful desert!
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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

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