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NBC | LOS ANGELES...
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Scientists Find Post-Tsunami Radiation in Sea Kelp, Seek to Expand Research
Scientists found radioactive kelp locally following Japan nuclear disaster
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By Melissa Pamer
| Thursday, Apr 5, 2012 | Updated 5:43 PM PDT
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Scientists Find Radiation in Food Chain
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Giant kelp off Southern California --such as the plants displayed here from the California Science Center -- were found to harbor radioactive iodine after Japan's nuclear disaster.
Two scientists who found radiation in sea kelp along the Southern California coast after Japan’s 2011 tsunami-induced nuclear disaster now hope to study whether contamination may be present in fish such as opaleye and other ocean creatures, including lobster and sea urchin.
The two researchers – from California State University, Long Beach – are hoping to expand on their recently published study showing that giant kelp contained up to 250 times the normal levels of a radioisotope of iodine in the weeks after last year's earthquake and resulting tsunami severely damaged Japan’s Fukushima Dai-ichi Nuclear Power Plant.
Kelp is the tall, wavy, green algae that provides near-shore habitat for many marine species, some of which eat the plant.
Tests showed that contamination in the kelp was gone within a month, and there’s no risk to humans from the Iodine-131 radiation. Still, the research indicates that radiation from the damaged Japanese nuclear facility reached California.
“Of course it’s cause for concern – because you don’t find this naturally in kelp or fish. It can’t be a positive thing. It also tells you that what happens half a world away can be detected,” said Cal State biology professor Steven Manley, a co-author of the study.
Manley and his co-author, marine biology professor Chris Lowe, hope next to find out whether other kinds of nuclear contamination – two radioisotopes of cesium that break down much more slowly than the Iodine-131 – are found in California marine life, including kelp and fish.
Those two cesium radioisotopes were found to contaminate waters around Japan, according to preliminary results of a study published this week by an international team of scientists.
“Our coastal environment is pretty complex. We get a lot of our food out there,” Manley said. “We should be monitoring it for these radioisotopes.”
Lowe wants to trace the concentration of radioactive cesium up the food chain in Southern California.
“Our question is: How much gets into the ocean? Kelp is really kind of the basis for the food web and is important habitat for many of our coastal marine animals,” Lowe said. “The next step is to look at organisms that eat kelp. “
Kelp is consumed by sea urchin and some fish, including opaleye, halfmoon and senorita, according to the study. Urchin are in turn eaten by lobster and some large fish species that could be consumed by humans.
Getting funding for the future research shouldn’t be a problem, given the attention that Lowe and Manley have gotten for their recent study, which was published last month in the journal Environmental Science & Technology. The study was first reported by nonprofit Environmental Health News and on Scientific American’s website.
A month after the earthquake after Japan, the Long Beach pair obtained kelp samples from seven sites along the coast: the Palos Verdes Peninsula in Los Angeles County; Crystal Cove, Laguna Beach and Corona del Mar in Orange County; and farther north in Santa Barbara, Pacific Grove and Santa Cruz.
Kelp from Corona del Mar had the highest concentration of radioactive iodine, up to 250 times the amount found in kelp before the Japanese nuclear reactor spewed radiation in the atmosphere.
Lowe said they believe the Corona del Mar site was more contaminated because a lot of urban runoff goes through the area – meaning radiation-contaminated rain would have accumulated there.
The scientists chose to study kelp – which grows from the ocean floor up to the surface, where it floats – because it is especially good at absorbing iodine from both the water and the atmosphere.
Lowe compared kelp to the badge that X-ray technicians where to show how much radiation they’ve been exposed to.
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Scientists Find Post-Tsunami Radiation in Sea Kelp,... more
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CNN...
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California nuclear plant shut indefinitely amid hunt to find cause of problems
By the CNN Wire Staff
updated 8:55 PM EDT, Fri April 6, 2012
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PHOTO:
The power plant has been shut down since this winter...
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STORY HIGHLIGHTS
The San Onofre nuclear plant has been shut down since radioactive gas escaped
Officials have said there's no harm to the public health, but can't identify the cause
The head of the NRC says the plant won't restart until a cause and plan is put forward
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(CNN) -- A large Southern California nuclear plant is out of commission indefinitely, and will remain so until there is an understanding of what caused problems at two of its generators and an effective plan to address the issues, the nation's top nuclear regulator said Friday.
Gregory Jaczko, chairman of the U.S. Nuclear Regulatory Commission, refused to give a timetable as to when the San Onofre nuclear plant could resume operation. He said only that his agency had "set some firm conditions" as to when that could happen.
"We won't make a decision (to approve the facility's restart) unless we're satisfied that public health and safety will be protected," Jaczko told reporters. "They have to demonstrate to us that they understand the causes, and ... that they have a plan to address them."
The power plant has been shut down since this winter, when a small amount of radioactive gas escaped from a steam generator during a water leak. At the time, federal regulators said there was no threat to public health, though they could not identify how much gas leaked or exactly why it had happened.
The water leak occurred in thousands of tubes that carry heated water from the reactor core through the plant's steam generators.
Leaks occur periodically in older units, but plant owner Southern California Edison replaced the four steam generators at San Onofre in 2010 and 2011 as part of a $680 million project. They are in units 2 and 3 of the nuclear facility; unit 1 went out of service in 1992.
Each of the 65-foot-tall, 640-ton generators -- built by Japan's Mitsubishi Heavy Industries -- are packed with thousands of narrow tubes that carry hot, pressurized water from the reactors. The heat produces steam in a separate loop that drives the plant's turbines and generators.
"Tubes are vibrating and rubbing against adjacent tubes and against support structures inside the steam generators," the agency noted.
Eight of the more than 9,700 tubes in one of the unit 3 generators failed a pressure test, while six tubes in unit 2's reactor needed to be plugged, the NRC has found. Another 186 tubes in unit 2, which was shut down for refueling at the time of the leak, were plugged "as a precautionary measure."
In addition to driving the turbines to create electricity, the steam generators are "one of the barriers between the radioactive material in the reactor core and ultimately the external environment," Jaczko noted.
Located near San Clemente, the San Onofre nuclear plant's twin reactors are "Southern California's largest and most reliable sources of electricity," according to Southern California Edison's website. When operational, the facility -- which is owned by that utility, San Diego Gas and Electric, and the city of Riverside -- supplies power for 1.4 million households at any given time.
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CNN's Greg Botelho contributed to this report.
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California nuclear plant shut indefinitely amid hunt to find cause... more
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The Woman Has died due to the Injuries Sustained, confirmed dead on March 24th 2012
http://youtu.be/RrnMYg62boMThe Woman Has died due to the Injuries Sustained, confirmed dead on March 24th 2012... more
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NBC | Los Angeles...
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Whales Trapped in Fishing Net Sought
Crews will search the waters of the Orange County coast Thursday
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By Angelo Simone and Robert Kovacik
Wednesday, Mar 28, 2012 | Updated 11:34 PM PDT
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VIDEO:
Robert Kovacik & Sean Browning
For the second time in less than a week, a whale has been spotted, trapped in a fishing net. Now, the search is on for that whale. NBC4's Robert Kovacik reports from Orange County.
Whale rescue specialists will spend Thursday looking for an entangled whale mother and calf. The whales were spotted Wednesday by Captain Dave Anderson of Dolphinsafari.com.
“It does break my heart. About a thousand dolphins and whales are dying in nets and fish gear entanglements everyday ,” Anderson said.
This is the second time in the past week that a whale has been stuck in a fishing net. The first whale, nicknamed Bart, found itself in a week-long snarl with a 50-foot net.
It took crews more than seven [exhausting] hours to remove it.
If you see this missing mother and calf, you’re encouraged to get an exact GPS location and call the Pacific Marine Mammal Center at 949-494-3050.
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http://media.nbclosangeles.com/images/654*368/9214359_N11PPKGWHALERESCUEko_722x406_2216640916.jpg
.NBC | Los Angeles...
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Whales Trapped in Fishing Net Sought
Crews will... more
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Los Angeles Times
Breaking news
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Federal agency bars Edison from restarting San Onofre plant
Los Angeles Times | March 27, 2012 | 2:52 p.m.
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The U.S. Nuclear Regulatory Commission, citing serious concerns about equipment failures at the San Onofre nuclear plant, on Tuesday barred plant operator Southern California Edison from restarting the plant until the problems are thoroughly understood and fixed.
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Breaking news
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Federal agency bars Edison from restarting... more
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http://www.nbclosangeles.com/news/local/Federal-Inspectors-Investigate-Problems-at-San-Onofre-143431286.html
NBC Los Angeles...
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Federal Inspectors Investigate Problems at San Onofre
Failed stress tests prompt inspection team to investigation the nuclear power plant, which leaked radiation in January
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By Dave Douglass and Antonio Castelan
| Monday, Mar 19, 2012 | Updated 9:08 PM PDT
A federal inspection team is beginning its examination of steam generator tubes at the San Onofre nuclear power plant. One of those tubes leaked in January, prompting a reactor shutdown, and more tubes failed during a series of tests last week. Antonio Castelan reports.
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KNBC-TV
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A federal inspection team is beginning its examination of steam generator tubes at the San Onofre nuclear power plant. One of those tubes leaked in January, prompting a reactor shutdown, and more tubes failed during a series of tests last week. Antonio Castelan reports.
An inspection team from the Nuclear Regulatory Commission began investigating faulty steam generator tubes at the San Onofre nuclear power plant Monday.
A series of failed tests last week involving steam generator tubes that are a key part of the plant's two reactors prompted the regulatory commission to send in a team of experts to find out why the vital energy source was failing.
The team plans to spend at least five days at the SoCal plant operated by Southern California Edison.
The trouble began in late January, when a tube in one of the reactors leaked.
That reactor was shut down, but not before a small amount of radioactive gas may have escaped into the atmosphere. Edison said neither plant employees nor the public was at risk.
Still, initial tests found that hundreds of steam generator tubes were showing signs of premature wear.
"We're seeing an unusual amount of wear in relatively new steam generators and, yes, that's unusual," said Victor Dricks with the Nuclear Regulatory Commission.
The problems at San Onofre have residents in nearby San Clemente worried.
"This is a huge amount of risk for us to be living so close to," said resident Patty Davis. "It's a big concern."
The federal inspectors will be looking at the design and construction of the plant's steam generators, as well as their transport from Japan where they were manufactured.
Each reactor contains thousands of steam generator tubes. San Onofre's second reactor is also shut down right now for routine maintenance.
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Click on link to view video:
http://media.nbclosangeles.com/images/654*368/9121595_N7PPKGSANONOFREINSPE_722x406_2212490620.jpg
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Tony D rewrites today's headlines so you don't have to read the news!
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Los Angeles Times...
Pacific Ocean study finds fish tainted by plastic
June 30, 2011 | 4:38 pm
Southern California researchers found plastic in nearly 1 in 10 small fish collected in the northern Pacific Ocean in the latest study to call attention to floating marine debris entering the food chain.
The study published this week by scientists at the Scripps Institution of Oceanography at UC San Diego estimated that fish in the northern Pacific Ocean are ingesting as much as 24,000 tons of plastic each year.
Although the research found a lower percentage of affected fish than previous studies, it is the latest to quantify how many fish are eating marine garbage — most of it confetti-sized flecks of discarded plastic — that has accumulated in vast, slow-moving ocean currents known as gyres.
The results came from a 2009 voyage a group of graduate students made to the so-called Pacific garbage patch, an area of high concentration of fragments of floating garbage about 1,000 miles off the California coast. Researchers cast nets into the water and collected 141 fish, mostly lanternfish measuring just a few inches, and took them to a laboratory in San Diego to dissect.
Scientists found plastic debris in 9.2% of their stomachs, much of it broken down into multicolored fragments smaller than a human fingernail. However, they believe the actual proportion of fish that have consumed plastic is significantly higher.
“We can’t tell how many fish ate plastic and died, how many fish ate plastic and regurgitated it or passed it out of their intestines,” said Rebecca Asch, a Scripps doctoral candidate in biological oceanography and one of the study's authors.
Because the widespread lanternfish is a common food source for larger fish, the study raises concerns that plastics and pollutants they contain, could be making their way up the food chain into seafood ingested by humans.
Scripps found a lower rate of plastic ingestion than previous research, such as a study by the Algalita Marine Research Foundation that found plastic in the stomachs of 35% of fish in the same general area of the Pacific.
Past studies may have been inflated by keeping nets in the water for longer periods, giving fish the chance to eat bits of plastic swept up in the nets with them, Scripps scientists said.
In their study, they tried to minimize that by towing their net only 15 minutes at a time. They stressed that their study broadly concludes the same thing: garbage is present in the food chain.
“We’re still finding a substantial amount of plastic,” Asch said. “It should be zero.”
--Tony Barboza
Photo: Two lanternfish and several bits of plastic collected in 2009 during the Scripps Environmental Accumulation of Plastic Expedition. Credit: J. LeichterLos Angeles Times...
Pacific Ocean study finds fish tainted by plastic
June 30,... more
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In this episode Joey and Richard visit the sights and scenes of California's Venice Beach Boardwalk community.
For more episodes and extras, visit thedartshow.com/In this episode Joey and Richard visit the sights and scenes of California's... more
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The seaside Southern California town of Coronado continues with super high gas prices reaching $4.84.
There was a steady flow of customers to pay the hefty prices.
Photo taken with Android phone - 3/28/11The seaside Southern California town of Coronado continues with super high gas prices... more
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Black's Beach in San Diego is known for its laissez-faire attitude toward nudity. While nude sunbathing is not legal, being clothed is not enforced.
We're told the La Jolla beach is a place for shriveled up old pervs who still think it's 1978. But for some reason, on a cold, windy, blustery day in 2011, a 27-year-old woman descended the perilous bluffs of Black's.
stuck on a bluff in the buff. Of course, the news helicopters arrived. And well, the shots were spectacular.
Rescuers were called to the cliffs near the Torrey Pines State Park glider port at 2:15 p.m. Tuesday, according to the North County Times.
The sunbather told them she was headed to the beach and had thrown her clothes down ahead of her (wise move).
But then she got to a place where going back up or continuing to go down didn't seem to be an option. So she froze. (Perhaps literally as well).Black's Beach in San Diego is known for its laissez-faire attitude toward nudity.... more
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Small amounts of radiation headed for California, but no health risk seen
Very low levels of radioactive isotopes from the damaged Japanese nuclear plant are expected to reach California as soon as Friday, but experts say the amount will be well within safe limits. A network of radiation monitors is keeping close watch.
By Ralph Vartabedian, Los Angeles Times
March 17, 2011
Small amounts of radioactive isotopes from the crippled Japanese nuclear power plant are being blown toward North America high in the atmosphere over the Pacific Ocean and will reach California as soon as Friday, according to experts.
A network of sensors in the U.S. and around the world is watching for the first signs of that fallout, though experts said they were confident that the amount of radiation would be well within safe limits.
Operated by the Environmental Protection Agency, the U.S. network known as Radnet is a system of 100 radiation monitors that work 24 hours a day, spread across the country in places such as Anaheim, Bakersfield and Eureka. In addition, a network of 63 sensors is operated by the Comprehensive Test Ban Treaty Organization, an international agency allied with the United Nations.
,NRC
Atmospheric experts said the material should begin showing up on the West Coast as early as Friday, though it could take up to an additional week for the 5,000-mile trip from Japan to Southern California. Although the organization has told its member countries that the first indication of radiation would hit on Friday, the plume from a North Korean nuclear test in 2006 took about two weeks to travel to North America, U.N. officials said.
The Nuclear Regulatory Commission, which oversees the U.S. nuclear industry, said Wednesday that it did not expect dangerous levels of radioactivity to hit the West Coast, Hawaii, Alaska or U.S. territories in the Pacific. But whatever levels reach the U.S. initially are likely to increase in subsequent days, because radioactive emissions from the damaged Fukushima Daiichi nuclear power plant have grown since the disaster began Friday. The NRC sharply raised its warning to American citizens in Japan, urging them to evacuate an area within 50 miles of the Fukushima complex. Japanese authorities have ordered an evacuation within about 12 miles of the plant.
The NRC released computerized projections showing that within half a mile of the plant, radiation levels were so high that one could receive a fatal dose, and that even 50 miles away one could receive more than 16 times the average annual dose all people are exposed to from natural sources.
Those numbers were sharply higher than ones the NRC released days earlier. But although the Fukushima reactors are leaking more radiation now, experts continued to say that the particles would wash out of the atmosphere before they could reach the U.S.
So far, Tokyo Electric Power Co., which operates the Fukushima facility, and the Japanese government have not released any measurements or estimates of the total amount of radioactivity released by the accident. These numbers would be crucial to better project whether the material could affect other Asian nations, the Pacific islands or even the U.S.
Edwin Lyman, a specialist at the nuclear watchdog group Union of Concerned Scientists, said that although it was true that the more radioactivity released in Japan the more could migrate away from the region, he did not think the U.S. was at serious risk.
"We can never say never," Lyman said. "My judgment is that there will probably be measurable radiation, but except for a few hot spots it is not something we should really worry about."
Lyman said that the NRC's warning Wednesday to Americans in Japan to evacuate 50 miles from the Fukushima reactors was a long-overdue admission that the agency's prior warnings of a 10-mile exclusion zone from U.S. reactors during an emergency was inadequate.
Key federal officials involved in the Radnet monitoring program have so far not disclosed their predictions for U.S. radioactive exposure. The projections are being developed by the National Atmospheric Release Advisory Center operated at the Lawrence Livermore National Laboratory in Northern California. The center, part of the Energy Department, uses sophisticated models on supercomputers to project the movement of radioactive particles and other toxic substances through the atmosphere.
However, a computer model of atmospheric movements developed by the Belgian Institute for Space Aeronomy shows that the Fukushima plumes could travel across the Pacific, though the levels of radioactivity that could reach the West Coast of the U.S. remain unclear.
It appears that all of the models, however, are not based on measurements of radioactivity at the source and a projection of actual radioactive fallout in the U.S., but rather project a relative scale of radioactivity. Since Japanese authorities have said little about the amount of the releases at Fukushima, nobody can say how much radioactivity will hit California.
The models show that even with prevailing easterly winds, the plumes whip back and forth over a wide area of Japan's east coast, Russia's Kamchatka peninsula and Alaska's Aleutian Islands. It is unknown whether nuclear fallout is hitting the vast wilderness of northeastern Asia.
Of particular concern, however, is radiation emanating from Fukushima's No. 3 reactor. That reactor uses plutonium fuel, which poses a special health risk even in small quantities if the fallout were to reach U.S. shores.
A leading radiological health expert at the Centers for Disease Control and Prevention, speaking on condition of anonymity, said Wednesday that the CDC was still confident that there would be no serious health consequences here. But CDC officials are watching the situation carefully.
"We have a saying: 'Modeling is OK, but measurement is everything,'" he said.
The Environmental Protection Agency said that it was watching the situation closely, but that its Radnet system had not yet detected radioactivity. It has added seven additional portable radiation monitors: two in Guam, three in Alaska and two in Hawaii.
PHOTO: A Radnet monitor on the roof of the Bay Area Air Quality Management building in San Francisco. (Associated Press)Small amounts of radiation headed for California, but no health risk seen
Very low... more
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Official: No foul play in massive fish kill in California harbor
By Michael Martinez, CNN
March 8, 2011 4:29 p.m. EST
Los Angeles (CNN) -- A southern California fish kill that authorities identified as more than a million sardines is not the result of any environmental foul play but rather is the product of natural forces, officials said Tuesday.
Floating fish were so pervasive in King Harbor Marina in Redondo Beach, California, that some moored boats seemed surrounded not by water but by the lifeless aquatic animals a foot deep.
"All evidence points to oxygen deprivation as cause of death," California Department of Fish and Game spokesman Andrew Hughan told CNN.
"There is no oil sheen, nor is there a chemical sheen," Hughan said.
Redondo Beach Police Sgt. Phil Keenan said authorities are confident of test results showing that oxygen deprivation caused the massive fish kill because the other part of the sardine school is alive and well in the mouth of the harbor.
Keenan said the floating fish are a foot deep, and clean-up boats will spend the next few days removing the silvery animals by net.
"Part of the sardine school is out in the channel of the harbor and they're doing fine," Keenan told CNN. "For some reason, this large school of sardines got chased into the harbor -- and they died off."
Authorities said that the sardines likely sought calm waters inside the 1,400-vessel marina Monday evening when winds were gusting up to 45 mph and the waters were rough.
"They like to follow each other and it only takes one to come in before the others follow," Brent Scheiwe, program director of the SEA Lab, a hands-on coastal science education center in Redondo Beach, told reporters at a press conference Tuesday.
"The fish found these back areas of the harbor, and then the oxygen depletion would have occurred... If it's rough out there, they will stay here in the waters where it's more sheltered," Scheiwe said.
"There is a risk of the same thing happening tonight," he added.
The harbor's algae may have contributed to the lack of oxygen, and then when the fish started dying, the resulting bacteria also consumed oxygen, Scheiwe said.
Once the fish got into the harbor, "they couldn't get out," said Redondo Beach Fire Chief Dan Madrigal.
About the extraordinary number of dead fish, Hughan stated that "while it is unusual, it is not unprecedented. This is natural selection."
Hughan said a necropsy, including a chemical analysis, will be performed on some of the dead fish.
In what officials described as $100,000 clean-up effort, crews had been moving the dead fish into the open ocean to let them decompose naturally, but they decided on a more efficient method of removing the fish from the marina and having them sent to be recycled for fertilizer, Madrigal told reporters.
Photo: Millions of dead anchovies float to surface in Redondo Beach
Older Article Today...
March 8th, 2011
01:35 PM ET
Officials say millions of the pungent, oily fish are covering the sea bottom in the harbor. They began rising to the surface Tuesday morning, the Daily Breeze in Torrance, outside Los Angeles, reported.
“We need to get rid of them,” Sgt. Phil Keenan of the Redondo Beach Police Department told the paper. “This is going to create a terrible pollution and public health issue if we don't.”
Fire, police and public works officials have yet to cite a definite cause, but Keenan said the fish appear to have died from lack of oxygen.
There were no red tides (oxygen-depleting algae blooms) or other obvious phenomena that could have caused the mass deaths, the paper reported.
“Yesterday, everything looked absolutely normal,” Walter Waite, who lives at the harbor, told the newspaper. “This morning when I got up, there were millions and millions of them floating everywhere.”
The temperature in Southern California is expected to climb into the 70s Tuesday, exacerbating the urgency of removing the scads of 6-inch fish scattered throughout the harbor.
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SCROLL DOWN FOR LATEST UPDATESOfficial: No foul play in massive fish kill in California harbor
By Michael Martinez,... more
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Gadahn, also known as Azzam the American, was born in 1978. He is a native of southern California and has appeared in several videotapes for Al-Qaeda since 2004.Gadahn, also known as Azzam the American, was born in 1978. He is a native of southern... more
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Crystal Cathedral struggling with bankruptcy problem! Crystal Cathedral, the beleaguered glass mega-church in Southern California, has reportedly filed for protection against bankruptcy, owing more than $7.0 million.Crystal Cathedral struggling with bankruptcy problem! Crystal Cathedral, the... more
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Another Mosque Emerging In Southern California?
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Study shakes up scientists' view of San Andreas earthquake risk
Researchers find major quakes on the southern section, on average, every 88 years — three times as often as previously thought. It's the strongest evidence yet that we're overdue for a massive quake.
San Andreas fault study
Photo: Sarah Robinson, 23, a graduate student at Arizona State University, runs along a trench at the Bidart Fan sector of the San Andreas fault in June 2009. She is on a team of geologists trying to construct a history of earthquakes on the San Andreas fault by reading lines of sediment in the earth. (Ricardo DeAratanha / Los Angeles Times / June 1, 2009)
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By Rong-Gong Lin II, Los Angeles Times
August 21, 2010
Southern California is long overdue for a major earthquake along the San Andreas fault, according to a landmark study of historic seismic activity released Friday.
The study, produced after several years of field studies in the Carrizo Plain area about 100 miles northwest of Los Angeles, found that earthquakes along the San Andreas fault have occurred far more often than previously believed.
For years, scientists have said major earthquakes occurred every 250 to 450 years along this part of the San Andreas. The new study found big temblors on the fault every 88 years, on average.
The last massive earthquake on that part of the fault was in 1857, leading scientists to warn that another such temblor is likely in Southern California.
"The next earthquake could be sooner than later," said Lisa Grant Ludwig, a UC Irvine earthquake expert and co-author of the study, which was published online in the journal Geology. "It was thought that we weren't at risk of having another large one any time soon. Well, now, it might be ready to rupture."
Other seismic experts described the revelation as a major change in the way they think about earthquake risks along the southern San Andreas fault.
Thomas Jordan, director of the Southern California Earthquake Center, said the fault is "locked and loaded. It's been a long time since an earthquake has occurred on that fault — over 150 years."
To reach the new conclusion, scientists dug trenches deep into the Carrizo Plain. They used carbon dating and sophisticated imaging technology known as lidar to find signs of earth movements. They were able to detect earthquakes dating back to the 15th century, creating a far more complete record than had previously been known.
The research found that earlier examinations of the San Andreas had badly undercounted the number of major earthquakes. Those were based on observations made in the 1970s when scientists used measuring tape to look for evidence of past earthquakes.
"Now we have better techniques," Grant Ludwig said. "We can see there's actually more earthquakes."
Scientists now estimate that earthquakes occurred on that section of the fault in 1417, 1462, 1565, 1614 and 1713.
The finding adds weight to the view of many seismologists that the San Andreas has been in a quiet period and that a major rupture is possible. A 2009 study, which Grant Ludwig also participated in, suggested that the San Andreas was overdue for a rupture. But Friday's report offers a much more grim estimate of how frequently quakes have occurred on that segment of the fault.
The San Andreas fault is considered one of the most dangerous in Southern California, partly because it is so long that its southern section is capable of producing a temblor as large as magnitude 8.1.
By contrast, earthquake experts consider 1994's destructive 6.7-magnitude Northridge quake, which occurred on a different fault, to be a medium-sized quake.
The San Andreas is a sleeping giant. It's hard to imagine the power of a huge quake on the southern section because the last one occurred more than a century ago when the area was sparsely populated. Just 4,000 people lived in Los Angeles at the time.
The 1857 temblor, with an estimated magnitude of 7.9, is known as the Fort Tejon quake, but that's a bit of a misnomer because it is thought to have started farther north, way up in Parkfield in Monterey County. The quake then barreled south on the San Andreas for about 200 miles, through Fort Tejon near the northern edge of what is now Los Angeles County, then east toward the Cajon Pass in San Bernardino County, near what is now the 15 Freeway.
The quake was so powerful that the soil liquefied, causing trees as far away as Stockton to sink. Trees were also uprooted west of Fort Tejon. The shaking lasted 1 to 3 minutes.
The study was conducted by scientists at UC Irvine and Arizona State University. As preliminary data went out for peer review, other earthquake scientists immediately took note.
The U.S. Geological Survey was so concerned that it dispatched its own team of investigators to the Carrizo Plain to look over the initial findings and review the evidence in the trenches.
"These investigators really were challenged by their scientific peers," said Ken Hudnut, a geophysicist at the U.S. Geological Survey. "And they made it through. They ran the gantlet and came through with a really solid paper."
Hudnut said the "Big One" wouldn't compare to most quakes Californians have endured. Such a large quake on the San Andreas, generally above a magnitude 7, would send enormous V-shape energy waves spreading out from the fault. If the earthquake energy hit the Los Angeles Basin, the soft sediment underneath it could actually amplify the waves, making the shaking worse.
Hudnut said the study offers both "bad news and good news," noting that it also concluded future earthquakes along that section of the San Andreas could be smaller than the 1857 quake.
"It's not the kind of news that ought to make people crawl into the fetal position. Rather, it's the kind of information that ought to once remind people about basic earthquake preparedness," Hudnut said.
Grant Ludwig said her research should motivate people to prepare.
"If you're waiting for someone to tell you when we're close to the next San Andreas earthquake, just look at the data," she said. "If we look at the only data we have, it's not very comforting. I'm preparing for that possibility."Study shakes up scientists' view of San Andreas earthquake risk
Researchers... more
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There's a hole in this possible earthquake pattern
The Mogi doughnut hypothesis, developed by a Japanese seismologist, holds that earthquakes occur in a circular pattern over decades, building up to one very large temblor in the doughnut hole.
A seismic hot spot
Photo: Signs in Parkfield, Calif., alert tourists that they are passing over the San Andreas fault. The area is so prone to earthquakes that scientists have wired it extensively to collect data. The San Andreas, along with the Elsinore and San Jacinto faults, would be enclosed in Southern California's so-called Mogi doughnut hole. Northern California’s doughnut hole includes the San Andreas and Hayward faults. (Spencer Weiner, Los Angeles Times / July 18, 2010)
PART ONE…
By Rong-Gong Lin II and Hector Becerra, Los Angeles Times
July 18, 2010
As UC Davis physicist and geologist John Rundle ponders the map of recent California earthquakes, he sees visions of a doughnut even Homer J. Simpson wouldn't like.
The doughnut is formed by pinpointing the recent quakes near Eureka, Mexicali and Palm Springs.
Seismologists call the possible pattern a Mogi doughnut. It's the outgrowth of a concept, developed in Japan, which holds that earthquakes sometimes occur in a circular pattern over decades —building up to one very large quake in the doughnut hole. Rundle and his colleagues believe that the recent quakes, combined with larger seismic events including the 1989 Loma Prieta and 1994 Northridge temblors, could be precursors to a far larger rupture.
They just don't know exactly when.
The idea of predicting earthquakes remains controversial and much debated among California's many seismologists. But as technology improves and the understanding of how earthquakes distribute energy grows, experts are gingerly offering improved "forecasts," some of which have been surprisingly prescient.
For example, Southern California was hit earlier this month by a 5.4 quake that struck in the mountains about 30 miles south of Palm Springs — several weeks after seismologists at the Jet Propulsion Laboratory and elsewhere warned that pressure was building in the San Jacinto fault zone, which is where the temblor occurred.
That forecast underscores new thinking by seismologists about how earthquakes occur.
In the past, experts paid less attention to how one fault was connected to another and how one earthquake could increase the chances of a quake on another fault. But now they believe that these connections are extremely important and that this year's temblors along the Mexican border and near Palm Springs seem to support the concept.
"Previously we would identify a fault, map it and name it," said Lisa Grant Ludwig, a UC Irvine earthquake expert. "What we've really got here is a network of faults. Maybe that's what we need to be thinking: more big-picture."
Seismologists made the forecast about the quake risk south of the Palm Springs area after seeing signs that the 7.2 Mexicali temblor in April had placed more pressure on the San Jacinto fault system, which extends from the border northwest 100 miles toward Riverside and San Bernardino. They were particularly concerned because the San Jacinto fault system connects to the massive 800-mile-long San Andreas fault, which last triggered the "Big One" in Southern California in 1857, leaving a trail of destruction from Central California to the Cajon Pass in the Inland Empire.
David Bowman, a geology professor at Cal State Fullerton, said his research indicates that the Mexicali quake — the largest to strike the region in nearly two decades — was actually triggered by a much smaller quake on a unnamed fault line. The small quake's energy "jumped on another fault and kept on going," causing the much larger Mexicali temblor that was felt all the way to Fresno.
"That fault the earthquake started on is so small, we don't even really know where it is. Yet that small earthquake — that would not have made the news at all — was able to jump onto another fault and become a magnitude 7.2 event," he said.
The big question is whether the Mexicali quake has made a destructive temblor in the L.A. area more likely. Experts see strong evidence that there is more pressure now on the San Jacinto and nearby Elsinore fault networks to the east of Los Angeles. The Elsinore fault zone is connected to the Whittier fault, which runs through densely populated sections of the L.A. area, including the San Gabriel Valley. As a result, there's a concern that a quake on the Whittier fault might be more likely.
The Mexicali quake has also turned into a treasure trove of data for earthquake experts. It comes at a time when quake technology has advanced in major ways. Sophisticated satellite images are being used to study creeping ground movement caused by tectonic pressure in advance of an earthquake.
New GPS ground monitoring equipment is tracking how far the ground has moved after a quake, allowing scientists to calculate locations of greater seismic stress. And research in the mountains west of Bakersfield, examining the tracks of earthquakes hundreds of years ago, is showing that catastrophic earthquakes — those as large as magnitude 8 — have occurred in Southern California more frequently than previously believed.
CONTINUED…There's a hole in this possible earthquake pattern
The Mogi doughnut hypothesis,... more
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A decent sized EQ just hit So Cal
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In this Travel Bug Robert episode, Robert travels to the beautiful shores of Malibu, California. This is where the celebrities live in Southern California. Well, this is where some of the celebrities live. There are a lot of celebrities, and Los Angeles County is pretty big. Malibu has a pretty high saturation of movie stars, though. Non-famous rich people live here, too. The good thing is even a person with a low salary can enjoy the pristine beaches here. As long as you can afford parking, you're good to relax on some of the best beaches in California.
Get more travel tips and videos at www.travelbugrobert.com.In this Travel Bug Robert episode, Robert travels to the beautiful shores of Malibu,... more
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