Scientists find evidence of tsunamis on Indian Ocean shores long before 2004A quarter-million people were killed when a tsunami inundated Indian Ocean coastlines the day after Christmas in 2004. Now scientists have found evidence that the event was not a first-time occurrence.
A team working on Phra Thong, a barrier island along the hard-hit west coast of Thailand, unearthed evidence of at least three previous major tsunamis in the preceding 2,800 years, the most recent from about 550 to 700 years ago. That team, led by Kruawun Jankaew of Chulalongkorn University in Thailand, included Brian Atwater, a University of Washington affiliate professor of Earth and space sciences and a U.S. Geological Survey geologist.
A second team found similar evidence of previous tsunamis during the last 1,200 years in Aceh, a province at the northern tip of the Indonesian island of Sumatra where more than half the deaths from the 2004 tsunami occurred.
Findings from both teams are published in the Oct. 30 edition of Nature.
Sparse knowledge of the region's tsunami history contributed to the loss of life in 2004, the scientists believe. Few people living along the coasts knew to heed the natural tsunami warnings, such as the strong shaking felt in Aceh and the rapid retreat of ocean water from the shoreline that was observed in Thailand.
But on an island just off the coast of Aceh most people safely fled to higher ground in 2004 because the island's oral history includes information about a devastating tsunami in 1907.
"A region's tsunami history can serve as a long-term warning system," Atwater said.
The research will reinforce the importance of tsunami education as an essential part of early warning, said Jankaew, the lead author.
"Many people in Southeast Asia, especially in Thailand, believe, or would like to believe, that it will never happen again," Jankaew said. "This will be a big step towards mitigating the losses from future tsunami events."
The team found evidence for previous tsunamis by digging pits and auguring holes at more than 150 sites on an island about 75 miles north of Phuket, a Thai tourist resort area ravaged by the 2004 tsunami. That tsunami was generated 300 miles to the west when the seafloor was warped during a magnitude 9.2 earthquake.
At 20 sites in marshes, the researchers found layers of white sand about 4 inches thick alternating with layers of black peaty soil. Witnesses confirmed that the top sand layer, just below the surface, was laid down by the 2004 tsunami, which ran 20 to 30 feet deep across much of the island.
Radiocarbon dating of bark fragments in soil below the second sand layer led the scientists to estimate that the most recent predecessor to the 2004 tsunami probably occurred between A.D. 1300 and 1450. They also noted signs of two earlier tsunamis during the last 2,500 to 2,800 years.
There are no known written records describing an Indian Ocean tsunami between A.D. 1300 and 1450, including the accounts of noted Islamic traveler Ibn Battuta and records of the great Ming Dynasty armadas of China, both of which visited the area at different times during that period. Atwater hopes the new geologic evidence might prompt historians to check other Asian documents from that era.
"This research demonstrates that tsunami geology, both recent and past tsunamis, can help extend the tsunami catalogues far beyond historical records," Jankaew said.
The new findings also carry lessons for the northwest coast of North America, where scientists estimate that many centuries typically elapse between catastrophic tsunamis generated by the Cascadia subduction zone.
"Like Aceh, Cascadia has a history of tsunamis that are both infrequent and catastrophic, and that originate during earthquakes that provide a natural tsunami warning," Atwater said. "This history calls for sustained efforts in tsunami education."
Note: This story has been adapted from a news release issued by University of Washington
WEATHER NOTE
Reburying the dead a grim task in Ike's wake
IN THE MARSH OF CAMERON PARISH, La. (AP) — Joe Johnson craned his neck from the airboat as it circled a patch of brown marsh grass. The runaway coffin was not where it was supposed to be.
Johnson pulled up to a pile of rocks, killed the motor and hopped out. After a few minutes of scouring along the tall, reedlike grass, he flagged down two fishermen.
"Can you possibly take me along the shoreline?" Johnson asked. "I'm looking for a casket."
Beyond the usual, dismal rebuilding, Hurricane Ike left another grim task when it struck last month: Its 13-foot storm surge washed an estimated 200 caskets out of their graves, ripping through most of Cameron Parish's 47 cemeteries and others in southwest Louisiana and coastal Texas. Some coffins floated miles into the marsh.
At Hollywood Cemetery in Orange, Texas, Ike unearthed about 100 caskets. Dozens more were disgorged in hard-hit Galveston.
Officials in coastal areas have long struggled with interring the dead, as caskets buried in low-lying areas are susceptible to being belched up by floodwaters. Some areas — most notably New Orleans — house the dead in above-ground crypts to keep them from drifting away in storms.
For many of the dead forced up by Ike, it wasn't their first disturbance. About 80 percent of the caskets in southwest Louisiana displaced by Ike were rousted by Hurricane Rita just three years earlier, said Zeb Johnson, the Calcasieu Parish deputy coroner who's headed casket recovery efforts for Rita and Ike.
Of the caskets ejected by Rita in September 2005, 335 were found and reburied, he said. Eighteen were never found.
"Our mother came out for Rita, and now she came out for Ike," said Debra Dyson, a commercial fisher whose house in Cameron was destroyed by Ike.
Dyson said coffins holding her brother-in-law and cousin also were heaved out by Rita. Ike was worse — the storm thrust out caskets containing her mother, brother-in-law, cousin, niece, three uncles and two aunts.
The one containing Dyson's mother floated to the same spot it came to rest after Rita, 22 miles from the cemetery. Only this time, it didn't take nine months to find it.
"It's hard to lose your home, but the first stop you make is that cemetery just to make sure they're still there, and it's heartbreaking when they're not," said Marilyn Dyson Elizondo, Dyson's sister who lives in Dayton, Texas.
Zeb Johnson helms a team of two employees, volunteer boat pilots and state prisoners to search hundreds of miles of marsh with loaned equipment and haul coffins back to shore. The work is backbreaking, with caskets weighed down by mud in swampy areas teeming with alligators and snakes and the stench of rotting marsh grass.
"It's a job that has to be done," said Joe Johnson, a funeral director and embalmer from Lake Charles who is not related to the deputy coroner.
Joe Johnson's half-hour ride with the fishermen didn't turn up the pink casket reported to the coroner's office, like so many other tips that don't pan out. An hour later, however, he returned with another coffin found in thick grass near a canal bank.
A hole was drilled into the silver metal container to drain out marsh muck and lighten the load for the airboat. Prisoners pulling the casket from the boat tipped it again to empty out more of the fetid water.
The coffin was trucked to the city coliseum in Lake Charles, where the Federal Emergency Management Agency was providing refrigerated trucks to hold caskets until reburial arrangements could be made.
"It's a slow process," Zeb Johnson said.
The Calcasieu Parish Coroner's Office is footing most of the search and recovery bill, which hasn't been tallied. But reburying the dead is estimated to cost as much as $100,000 on top of the recovery costs, with much of the money needed for new caskets and vaults. Zeb Johnson wasn't sure who'll cover that price tag, so he wasn't sure when reburial could begin.
More than 140 coffins had been found by Wednesday, and about 20 others that didn't stray far from their burial sites were quickly reburied. Zeb Johnson doesn't expect to find all of the two dozen or more that remain missing.
"The first day we found caskets that had floated 30 miles from their cemeteries," he said. "You just have caskets floating out in the marsh. At least seven of these caskets ended up in Texas, kind of like boats, they just got out in the currents from the high waters and carried them to Texas."
The identification work in many instances is easier this time around. Bodies found after Rita were tagged with special markers, as were the silver metal coffins in which they were reburied. The coffins include a scroll with the deceased's name, where they were buried and other information.
A few families are considering reburials on higher ground. Cameron Parish's government has proposed requiring deeper burials.
Elizondo, whose family awaits word on the missing Dyson caskets, said her brother was buried in January in a deeper vault than those that housed her missing relatives. Ike didn't disturb her brother, so Elizondo wants to rebury her mother the same way, though it is more expensive.
"It's worth it. That way we have the peace of mind that mom won't be gone again," Elizondo said. "We've even offered to do the backhoe ourselves. We just don't want her coming back up again."
MARITIME NOTE
Napoli bill put at staggering £120m
Insurers of the 62,000-tonne container ship, beached off East Devon in January 2007, have estimated the total bill for the wreck at £120 million.
It means the clean-up, salvage, vessel and cargo costs from the Napoli are second only to the Exxon Valdez – the tanker which spilt 10.8 million gallons of crude oil into the sea at Prince William Sound, Alaska, in 1989.
One of the biggest environmental disasters to occur at sea, its costs have run into hundreds of millions of pounds. News of the vast bill emerged as the Maritime and Coastguard Agency released a report into the grounding, making 11 recommendations.
Charles Hattersley, a Plymouth- based marine law expert, said the huge costs were "understandable" given the nature of the incident. But he said the scale, and cost, of the incident had not been matched by the Government's response.
"In my view, the Government should have instigated its own public inquiry into what happened," said Mr Hattersley, a partner at Ashfords solicitors. "Instead, Devon County Council has had to step up to the plate."The cost of the Napoli grounding was revealed by the London Steam-Ship Owners' Mutual Insurance Association Limited, otherwise known as the P&I (Protection and Indemnity) Club. It is managed by London-based A Bilbrough and Company Limited.
In its annual report, chief executive Paul Hinton confirmed the Napoli's £120 million estimated bill was the "second most expensive claim ever".
He said the beaching of the vessel had avoided "a potentially very grave environmental disaster". He described the aftermath as "an enormous challenge in technical, regulatory and legal terms".
Mr Hinton added: "The salvage and removal of the wreck of the ship and her containers, as well as the disposal of cargo within the containers, has been a unique experience in a number of respects, but importantly, it is the first occasion on which a large container ship has foundered in a recoverable condition off the coast of a European state.
"Other container ships have been salvaged following fire or explosion (resulting in the loss of a relatively small proportion of their cargo) or have sunk in deep water (with the total loss of ship and cargo). "The MSC Napoli represents the first occasion when almost the totality of a ship's container cargo has been brought ashore in both sound and extensively wetted condition, for forwarding and disposal.
"This huge undertaking has also taken place under the watchful eye of one of the most robust environmental regulatory regimes in the world and every aspect of the waste cargo handling and disposal operation, involving the disposal of some 30,000 tonnes of cargo, has been scrutinised by the Environment Agency."
He said the total cost of recovering the cargo and removing the ship had escalated to some £53 million. Yesterday, the MCA's 103-page report into the incident was submitted to the Devon County Council-led inquiry into the grounding.
It concedes that lessons can be learned to improve communication between organisations and streamlining the jurisdiction between land and sea.
The report highlights 11 recommendations which include improving communications between salvagers and land-based response organisations, and educating other agencies on marine emergency procedures.
It says the next Marine National Contingency Plan should assess who is best-placed to take responsibility for protecting and cleaning the shoreline, and also how various response centres could be merged to offer more effective communication and partnerships.
But the professionalism of those involved in the operations at sea meant the risk of years of oil pollution along the coasts of Devon was averted.
The report summarises the MCA's activities from January 18 last year when the Napoli, bound for South Africa, "suffered a catastrophic hull failure" when she was 50 miles south of Cornwall's Lizard peninsula, and the 26-strong crew was rescued after taking to life-rafts.
It addresses the controversial issue of why the Napoli was towed to British waters instead of French, when its position was between the two. "The conclusion was that the least environmentally risky option was to tow the vessel to a place of refuge in UK waters," it says.
The Secretary of State's Representative for Maritime Salvage and Intervention, Robin Middleton, decided the ship was in danger of breaking up and polluting the English Channel and should be towed to Portland. But, during the operation, the weather deteriorated and the salvors and Mr Middleton decided to beach her in Lyme Bay to minimise the pollution threat.
The report says the only option was to ground the ship on shallow waters to avoid "almost certain" break-up. The Napoli had 3,664 tonnes of fuel oil and marine diesel on board.
"The spilled oil would have escaped and found its way on to many beaches, possibly on both sides of the Channel, for many years," says the report.
The report accepts that the "understandable" confusion over the legislation governing salvage had been exploited by salvagers who descended on Branscombe's beaches after 50 containers washed ashore.
RS
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