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  • richardmitnick 11:59 am on February 21, 2019 Permalink | Reply
    Tags: "Rare L.A. mega-storm could overwhelm dam and flood dozens of cities experts say", A government study however used computer models to estimate the effects of 900-year 7500-year and 18000-year storm events, Epic runoff from the San Gabriel Mountains could rapidly overwhelm a flood control dam on the San Gabriel river and unleash floodwaters from Pico Rivera to Long Beach says a recent analysis by the U.S, In a series of recent public hearings corps officials told residents that the 60-year-old Whittier Narrows Dam no longer met the agency’s tolerable-risk guidelines and could fail in the event of a v, In each case catastrophic flooding could extend from Pico Rivera to Long Beach inundating cities including Artesia Bell Gardens Bellflower Carson Cerritos Commerce Compton Cypress Downey Hawaiian Gard, L A Times, Scientists call it California’s “other big one”- what experts call an ARkStorm, This rare mega-storm — which some say is rendered all the more inevitable due to climate change — would last for weeks and send more than 1.5 million people fleeing as floodwaters inundated cities, , Whittier Narrows Dam   

    From L.A. Times via UCLA: “Rare L.A. mega-storm could overwhelm dam and flood dozens of cities, experts say” 

    From L.A. Times

    via

    UCLA bloc

    UCLA

    Feb 18, 2019
    Louis Sahagun

    1
    Lead engineer Douglas Chitwood at the Whittier Narrows Dam. The U.S. Army Corps of Engineers says the aging structure could fail in heavy rains. (Irfan Khan / Los Angeles Times)

    Scientists call it California’s “other big one,” and they say it could cause three times as much damage as a major earthquake ripping along the San Andreas Fault.

    Although it might sound absurd to those who still recall five years of withering drought and mandatory water restrictions, researchers and engineers warn that California may be due for rain of biblical proportions — or what experts call an ARkStorm.

    2
    (Los Angeles Times)

    This rare mega-storm — which some say is rendered all the more inevitable due to climate change — would last for weeks and send more than 1.5 million people fleeing as floodwaters inundated cities and formed lakes in the Central Valley and Mojave Desert, according to the U.S. Geological Survey. Officials estimate the structural and economic damage from an ARkStorm (for Atmospheric River 1,000) would amount to more than $725 billion statewide.

    In heavily populated areas of the Los Angeles Basin, epic runoff from the San Gabriel Mountains could rapidly overwhelm a flood control dam on the San Gabriel river and unleash floodwaters from Pico Rivera to Long Beach, says a recent analysis by the U.S. Army Corps of Engineers.

    3
    An aerial view of the Whittier Narrows Dam in the area between Montebello and Pico Rivera. (Brian van der Brug / Los Angeles Times)

    In a series of recent public hearings, corps officials told residents that the 60-year-old Whittier Narrows Dam no longer met the agency’s tolerable-risk guidelines and could fail in the event of a very large, very rare storm, such as the one that devastated California more than 150 years ago.

    Specifically, federal engineers found that the Whittier Narrows structure could fail if water were to flow over its crest or if seepage eroded the sandy soil underneath. In addition, unusually heavy rains could trigger a premature opening of the dam’s massive spillway on the San Gabriel River, releasing more than 20 times what the downstream channel could safely contain within its levees.

    The corps is seeking up to $600 million in federal funding to upgrade the 3-mile-long dam, and say the project has been classified as the agency’s highest priority nationally, due to the risk of “very significant loss of life and economic impacts.”

    The funding will require congressional approval, according to Doug Chitwood, lead engineer on the project.

    Standing atop the 56-foot-tall dam recently, Chitwood surveyed the sprawl of working-class homes, schools and commercial centers about 13 miles south of Los Angeles and said, “All you see could be underwater.”

    4
    Engineer Douglas Chitwood explains the workings of the Whittier Narrows Dam, which engineers predict would not stand up to a mega-storm. (Irfan Khan / Los Angeles Times)

    The dam — which stretches from Montebello to Pico Rivera and crosses both the San Gabriel and Rio Hondo rivers — is one of a number of flood control facilities overseen by the corps. Throughout much of the year, it contains little water.

    A government study, however, used computer models to estimate the effects of 900-year, 7,500-year and 18,000-year storm events.

    5
    (Los Angeles Times)

    In each case, catastrophic flooding could extend from Pico Rivera to Long Beach, inundating cities including Artesia, Bell Gardens, Bellflower, Carson, Cerritos, Commerce, Compton, Cypress, Downey, Hawaiian Gardens, La Palma, Lakewood, Long Beach, Lynwood, Montebello, Norwalk, Paramount, Rossmoor, Santa Fe Springs, Seal Beach and Whittier. Officials say as many as 1 million people could be affected.

    Among the communities hardest hit in a dam failure would be Pico Rivera, a city of about 63,000 people immediately below the dam. In a worst-case scenario, it could be hit with water 20 feet deep, and evacuation routes would be turned into rivers. Downey could see 15 feet of water; Santa Fe Springs, 10 feet.

    In recent years, officials with the U.S. Department of Interior and the U.S. Geological Survey have sought to raise awareness of the threat of mega-storms and promote emergency preparedness. Part of the challenge, however, has been characterizing the scale of such storms. When scientists speak of a 900-year storm, that does not mean the storm will occur every 900 years, or that such a storm cannot happen two years in a row. It means that such a storm has a 1 in 900 — or .1% — chance of occurring in any given year.

    The estimates used by the U.S. Army Corps of Engineers are intended to protect the region from a storm similar to the one that hit California during the rainy season of 1861-1862. That’s when a series of intense storms hammered the state for 45 days and dropped 36 inches of rain on Los Angeles. So much water fell that it was impossible to cross the Central Valley without a boat, and the state capital was moved temporarily from Sacramento to San Francisco.

    Some researchers, however, say climate change has cast doubt on 20th-century assumptions. They argue [nature climate change] that, in a warming world, regions such as California will experience more whiplashing shifts between extremely dry and extremely wet periods — similar to how California’s long drought was quickly followed by the wettest rainy season on record in 2016-2017. These intense cycles will seriously challenge California’s ability to control flooding as well as store and transport water.

    Daniel Swain, a UCLA climate scientist, said hydrological and forecast data used by the corps must be updated.

    “The Army Corps’ estimates of the impacts of an extremely serious weather event … are categorically underestimated,” he said. “That’s because we only have about a century of records to refer to in California. So, they are extrapolating in the dark.”

    As an example, Swain said until recently it was thought a flood the magnitude of the 1861-1862 event was likely to occur every 1,000 to 10,000 years. New research has changed that view considerably, Swain said.

    “A newer study suggests the chances of seeing another flood of that magnitude over the next 40 years are about 50-50,” he said.

    Whittier Narrows, Swain added, is therefore just one of “many pieces of water infrastructure that may not be up to the challenge of the brave new climate of the 21st century.”

    4
    Men ride horseback in the shadow of Whittier Narrows Dam, which Army Corp of Engineers officials say no longer meets their tolerable-risk guidelines. (Irfan Khan / Los Angeles Times)

    Such was the conclusion of a study conducted by UC Irvine researchers and published recently in the scientific journal Geophysical Research Letters. After examining 13 California reservoirs — most of them over 50 years old — the authors argued that the risk of dam failure was likely to increase in a warming climate. The study cited the 2017 crisis at Oroville Dam, when extreme water flows caused the dam spillway to disintegrate and triggered the evacuation of more than 180,000 people.

    In the case of Whittier Narrows Dam, Travis Longcore, a spatial scientist at USC, suggested people had grown complacent about the effectiveness of the area’s flood control system. “People tend to forget about the power of Southern California’s river systems,” he said.

    The San Gabriel River ranks among the steepest rivers in the United States, plunging 9,900 feet from boulder-strewn forks in the mountains down to Irwindale. It then meanders in a gravelly channel before arriving at lush Whittier Narrows — a natural gap in the hills that form the southern boundary of the San Gabriel Valley. From there, its flows are tamed in a concrete-covered channel for most of its final journey to the Pacific Ocean.

    Now, based on the corps’ findings, L.A. County and municipal officials are working with the federal government to develop emergency plans that can be implemented if necessary before the repair project at the dam is completed in 2026.

    Pico Rivera has undertaken an improved preparedness program, but only recently.

    Robert Alaniz, a spokesman for Pico Rivera, said the city was using a $300,000 grant from the California Department of Water Resources to revise its existing evacuation plans, which use major thoroughfares crossing the San Gabriel River to the east and Rio Hondo to the west.

    Separately, Los Angeles County Supervisor Hilda Solis said she discussed the importance of the Whittier Narrows Dam project with members of Congress during a visit to Washington, D.C., in January.

    In the meantime, David Reid, a water historian and expert on the Whittier Narrows area, suggested “the false sense of security included in the phrase ‘900-year flood’ combined with the promises of 20th century water infrastructure have put us in a bind.”

    “That’s because a mega-flood is impossible to predict,” he said. “And if the water infrastructure fails, we’re in big trouble.”

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    UC LA Campus

    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
  • richardmitnick 9:25 am on March 23, 2017 Permalink | Reply
    Tags: , L A Times, Massive damage throughout Southern California, Newport-Inglewood fault, ,   

    From UCLA via L.A. Times: “Notorious L.A. earthquake fault more dangerous than experts believed, new research shows” 

    UCLA bloc

    UCLA

    1

    L.A. Times

    3.21.17
    Rong-Gong Lin II

    The Newport-Inglewood fault has long been considered one of Southern California’s top seismic danger zones because it runs under some of the region’s most densely populated areas, from the Westside of Los Angeles to the Orange County coast.

    But new research shows that the fault may be even more dangerous than experts had believed, capable of producing more frequent destructive temblors than previously suggested by scientists.

    A new study [Nature] has uncovered evidence that major earthquakes on the fault centuries ago were so violent that they caused a section of Seal Beach near the Orange County coast to fall 1½ to 3 feet in a matter of seconds.

    “It’s not just a gradual sinking. This is boom — it would drop. It’s very rapid sinking,” said the lead author of the report, Robert Leeper, a geology graduate student at UC Riverside who worked on the study as a Cal State Fullerton student and geologist with the U.S. Geological Survey.

    The study of the Newport-Inglewood fault focused on the wetlands of Seal Beach. But the area of sudden dropping could extend to other regions in the same geologic area of the Seal Beach wetlands, which includes the U.S. Naval Weapons Station and the Huntington Harbour neighborhood of Huntington Beach.

    Leeper and a team of scientists at Cal State Fullerton had been searching the Seal Beach wetlands for evidence of ancient tsunami. Instead, they found buried organic deposits that they determined to be the prehistoric remains of marsh surfaces, which they say were abruptly dropped by large earthquakes that occurred on the Newport-Inglewood fault.

    Those earthquakes, roughly dated in 50 BC, AD 200 and the year 1450 — give or take a century or two — were all more powerful than the magnitude 6.4 Long Beach earthquake of 1933, which did not cause a sudden drop in the land, Leeper said.

    2
    The area shaded in solid white, which spans the Seal Beach National Wildlife Refuge and the Huntington Harbour area of Huntington Beach, highlights the zone along the fault that may experience abrupt sinking during future earthquakes on the Newport-Inglewood fault. (Robert Leeper / Scientific Reports)

    As a result, the observations for the first time suggest that earthquakes as large as magnitudes 6.8 to 7.5 have struck the Newport-Inglewood/Rose Canyon fault system, which stretches from the border of Beverly Hills and Los Angeles through Long Beach and the Orange County coast to downtown San Diego.

    The newly discovered earthquakes suggest that the Newport-Inglewood fault is more active than previously thought. Scientists had believed the Newport-Inglewood fault ruptured in a major earthquake once every 2,300 years on average; the latest results show that a major earthquake could come once every 700 years on average, Leeper said.

    It’s possible the earthquakes can come more frequently than the average, and data suggest they have arrived as little as 300 years apart from one another.

    If a magnitude 7.5 earthquake did rupture on the Newport-Inglewood/Rose Canyon fault system, such a temblor would bring massive damage throughout Southern California, said seismologist Lucy Jones, who was not affiliated with the study. Such an earthquake would produce 45 times more energy than the 1933 earthquake.

    “It’s really clear evidence of three earthquakes on the Newport-Inglewood that are bigger than 1933,” Jones said of the earthquake that killed 120 people. “This is very strong evidence for multiple big earthquakes.”

    The idea that the Newport-Inglewood fault could produce more powerful earthquakes than what happened in 1933 has been growing over the decades. Scientists have come to the consensus that the Newport-Inglewood fault could link up with the San Diego County coast’s Rose Canyon fault, producing a theoretical 7.5 earthquake based on the length of the combined fault system.

    An earthquake of magnitude 7 on the Newport-Inglewood fault would hit areas of Los Angeles west of downtown particularly hard.

    “If you’re on the Westside of L.A., it’s probably the fastest-moving big earthquake that you’re going to have locally,” Jones said. “A 7 on the Newport-Inglewood is going to do a lot more damage than an 8 on the San Andreas, especially for Los Angeles.”

    The study focused on taking samples of sediment underneath the Seal Beach National Wildlife Refuge in 55 locations across a broad zone, mapping buried layers for signs of past seismic activity.

    To do this, scientists used a vibrating machine to push down a 20-foot-long, sharp-tipped pipe into the sediment and extract sediment samples that gave them a look at what has happened geologically underneath the site.

    They found a repeating pattern where living vegetation on the marsh suddenly dropped by up to 3 feet, submerging it underwater, eventually killing everything on the surface and later buried.

    “We identified three of these buried layers [composed of] vegetation or sediment that used to be at the surface,” Leeper said. “These buried, organic-rich layers are evidence of three earthquakes on the Newport-Inglewood in the past 2,000 years.”

    Earthquakes elsewhere have also caused sudden drops in land, such as off the Cascadia subduction zone along the coast of Oregon and Washington. There, pine trees that once grew above the beach suddenly dropped below sea level, killing the trees as salt water washed over their roots, said study coauthor Kate Scharer, a USGS research geologist.

    Another reason pointing to major earthquakes as a cause is the existence of a gap — known as the Sunset Gap — in the Newport-Inglewood fault that roughly covers the Seal Beach National Wildlife Refuge and Huntington Harbour.

    The gap is oriented in a way that, if a major earthquake strikes, land could suddenly drop. Such depressions have formed in other Southern California faults, which have created Lake Elsinore from the Elsinore fault, and created Quail Lake, Elizabeth Lake and Hughes Lake from the San Andreas fault, Jones said.

    While the scientists focused their study on the Seal Beach wetlands, because Huntington Harbour and the Naval Weapons Station area also lie in the same gap of the Newport-Inglewood fault, it could be possible that the sinking would extend to those areas as well, Leeper said.

    But further study would be a good idea for those areas. It’s possible that an investigation of Huntington Harbour, for instance, would show that land underneath it did not drop during earthquakes but moved horizontally, like much of the rest of the Newport-Inglewood fault, Scharer said.

    Sudden dropping of land could cause damage to infrastructure, Scharer said, such as roads or pipes not designed to handle such a rapid fall.

    Nothing in the new study offers guidance for when the next major earthquake on the Newport-Inglewood fault will strike next. “Earthquakes can happen at any time. We can’t predict them. All we can do is try to understand how often they occur in the past, and be prepared for when the next one does occur,” Leeper said.

    Scientists generally say that the chances of a major quake on the San Andreas fault are higher in our lifetime because that fault is moving so much faster than the Newport-Inglewood, at a rate of more than 1 inch a year compared with a rate of one-twenty-fifth of an inch a year.

    But it’s possible a big earthquake on the Newport-Inglewood fault could happen in our lifetime.

    The study was published online Monday in Scientific Reports, a research publication run by the journal Nature [link is above].

    Besides Leeper and Scharer, the other coauthors of the study are Brady Rhodes, Matthew Kirby, Joseph Carlin and Angela Aranda of Cal State Fullerton; Scott Starratt of the USGS; Simona Avnaim-Katav and Glen MacDonald of UCLA; and Eileen Hemphill-Haley.

    4
    Researchers studied prehistoric layers of sediment in a gap of the Newport-Inglewood fault known as the Sunset Gap. They took sediment samples from 55 locations that suggest the land in this region suddenly dropped by as much as 3 feet during major earthquakes. (Robert Leeper / Scientific Reports)

    See the full article here .

    You can help many citizen scientists in detecting earthquakes and getting the data to emergency services people in affected area.

    QCN bloc

    Quake-Catcher Network

    The Quake-Catcher Network is a collaborative initiative for developing the world’s largest, low-cost strong-motion seismic network by utilizing sensors in and attached to internet-connected computers. With your help, the Quake-Catcher Network can provide better understanding of earthquakes, give early warning to schools, emergency response systems, and others. The Quake-Catcher Network also provides educational software designed to help teach about earthquakes and earthquake hazards.

    After almost eight years at Stanford, and a year at CalTech, the QCN project is moving to the University of Southern California Dept. of Earth Sciences. QCN will be sponsored by the Incorporated Research Institutions for Seismology (IRIS) and the Southern California Earthquake Center (SCEC).

    The Quake-Catcher Network is a distributed computing network that links volunteer hosted computers into a real-time motion sensing network. QCN is one of many scientific computing projects that runs on the world-renowned distributed computing platform Berkeley Open Infrastructure for Network Computing (BOINC).

    BOINCLarge

    BOINC WallPaper

    The volunteer computers monitor vibrational sensors called MEMS accelerometers, and digitally transmit “triggers” to QCN’s servers whenever strong new motions are observed. QCN’s servers sift through these signals, and determine which ones represent earthquakes, and which ones represent cultural noise (like doors slamming, or trucks driving by).

    There are two categories of sensors used by QCN: 1) internal mobile device sensors, and 2) external USB sensors.

    Mobile Devices: MEMS sensors are often included in laptops, games, cell phones, and other electronic devices for hardware protection, navigation, and game control. When these devices are still and connected to QCN, QCN software monitors the internal accelerometer for strong new shaking. Unfortunately, these devices are rarely secured to the floor, so they may bounce around when a large earthquake occurs. While this is less than ideal for characterizing the regional ground shaking, many such sensors can still provide useful information about earthquake locations and magnitudes.

    USB Sensors: MEMS sensors can be mounted to the floor and connected to a desktop computer via a USB cable. These sensors have several advantages over mobile device sensors. 1) By mounting them to the floor, they measure more reliable shaking than mobile devices. 2) These sensors typically have lower noise and better resolution of 3D motion. 3) Desktops are often left on and do not move. 4) The USB sensor is physically removed from the game, phone, or laptop, so human interaction with the device doesn’t reduce the sensors’ performance. 5) USB sensors can be aligned to North, so we know what direction the horizontal “X” and “Y” axes correspond to.

    If you are a science teacher at a K-12 school, please apply for a free USB sensor and accompanying QCN software. QCN has been able to purchase sensors to donate to schools in need. If you are interested in donating to the program or requesting a sensor, click here.

    BOINC is a leader in the field(s) of Distributed Computing, Grid Computing and Citizen Cyberscience.BOINC is more properly the Berkeley Open Infrastructure for Network Computing, developed at UC Berkeley.

    Earthquake safety is a responsibility shared by billions worldwide. The Quake-Catcher Network (QCN) provides software so that individuals can join together to improve earthquake monitoring, earthquake awareness, and the science of earthquakes. The Quake-Catcher Network (QCN) links existing networked laptops and desktops in hopes to form the worlds largest strong-motion seismic network.

    Below, the QCN Quake Catcher Network map
    QCN Quake Catcher Network map

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    UC LA Campus

    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
  • richardmitnick 5:57 pm on July 20, 2014 Permalink | Reply
    Tags: , , , , , L A Times,   

    From L.A.Times: “Suddenly, the sun is eerily quiet: Where did the sunspots go?” 

    L A Times

    L.A. Times

    July 18, 2014
    Deborah Netburn

    Our sun has gone quiet. Almost too quiet.

    A few weeks ago it was teeming with sunspots, as you would expect since we are supposed to be in the middle of solar maximum — the time in the sun’s 11-year cycle when it is the most active.

    sun
    A nearly spot-free sun as viewed by NASA’s Solar Dynamics Observatory on July 18.

    But now, there is hardly a sunspot in sight. If you look closely at the image above, taken on July 18 by NASA’s Solar Dynamics Observatory, you will see a tiny smidge of brown just right of center where a small sunspot appears to be developing. But just one day before, there truly was nothing. It was a totally spotless day.

    So what’s going on here? Is the “All Quiet Event” as solar physicist Tony Phillips dubbed it, a big deal or not?

    “It is weird, but it’s not super weird,” said Phillips, who writes about solar activity on his website SpaceWeather.com. “To have a spotless day during solar maximum is odd, but then again, this solar maximum we are in has been very wimpy.”

    Phillips notes this is the weakest solar maximum to have been observed in the space age, and it is shaking out to be the weakest one in the past 100 years, so the spotless day was not so out of left field.

    “It all underlines that solar physicists really don’t know what the heck is happening on the sun,” Phillips said. “We just don’t know how to predict the sun, that is the take away message of this event.”

    sunspot
    Granules-like structure of surface of sun and sunspots (size around 20’000km). Visible light. Taken by Hinode’s Solar Optical Telescope (SOT). These sunspots belong to AR 10930 where X3.4 flare occurred on that day.

    NASA Hinode
    NASA/Hinode

    Sunspots are interesting to solar observers because they are the region of the sun where solar activity such as solar flares (giant flashes of light) and coronal mass ejections (when material from the sun goes shooting off into space) originate.

    solar flare
    On August 31, 2012 a long prominence/filament of solar material that had been hovering in the Sun’s atmosphere, the corona, erupted out into space at 4:36 p.m. EDT

    They are caused by highly concentrated magnetic fields that are slightly cooler than the surrounding surface of the sun, which is why they appear dark to us. Those intense magnetic fields can get twisted up and tangled, which causes a lot of energy to build up. Solar flares and coronal mass ejections occur when that energy is released in a very explosive way.

    Alex Young, a heliophysicist at Goddard Space Flight Center, said it is hard to say what is and isn’t unusual when it comes to the sun.

    “We’ve only been observing the sun in lots of detail in the last 50 years,” he said. “That’s not that long considering it’s been around for 4.5 billion years.”

    And it’s not like astronomers have never seen the sun this quiet before. Three years ago, on Aug. 14, 2011, it was completely free of sunspots. And, as Phillips points out, that year turned out to have relatively high solar activity overall with several X-class flares. So in that case, the spotless sun was just a “temporary intermission,” as he writes on his website.

    Whether this quiet period will be similarly short-lived or if it will last longer remains to be seen.


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