BP finally seals leaking Gulf of Mexico oil well

19 September 2010

The ruptured well that has spewed millions of barrels of oil into the Gulf of Mexico has finally been sealed, US officials say.

A pressure test showed a cement plug put in place by BP to permanently "kill" the well was holding.

President Obama hailed the news, vowing to continue to help those affected.

The worst offshore oil spill in US history began after the Deepwater Horizon rig blew up on 20 April, killing 11 workers and later sinking.

'Important milestone'
The top US federal official overseeing the disaster, Coast Guard Adm Thad Allen, said on Sunday that the well was now "effectively dead".

"Additional regulatory steps will be undertaken but we can now state definitively that the Macondo Well poses no continuing threat to the Gulf of Mexico," Adm Allen said.

A temporary cap had sealed the flow on 15 July while a relief well was dug. That well finally linked up with the ruptured well on Thursday, allowing workers to start pumping in the cement, removing the need for the cap and creating the permanent "kill".

The disaster has brought an environmental nightmare to hundreds of miles of US coast. It led to BP chief executive Tony Hayward standing down and the imposition of a moratorium on deepwater offshore drilling.

In a statement, President Obama hailed Sunday's "important milestone" and thanked all those who had "worked around the clock to respond to this crisis and ultimately complete this challenging but critical step to ensure that the well has stopped leaking forever".

He said he remained "committed to doing everything possible to make sure the Gulf Coast recovers fully from this disaster".

He added: "This road will not be easy, but we will continue to work closely with the people of the Gulf to rebuild their livelihoods and restore the environment that supports them."

The cost of the disaster to BP has been massive. It has created a compensation fund of $20bn and paid out another $8bn so far in the clean-up campaign.

This final sealing will mean BP can leave the site and concentrate on dealing with the aftermath of the spill.

At the beginning of August, the US government announced that almost three-quarters of the oil had been cleaned up or broken down by natural forces.

The remaining quarter was thought to be "degrading quickly".

But more recent research noted an undersea plume of crude oil-based chemicals up to 200m high and 2km wide, extending 35km from the spill site.

Despite optimism about the clean-up, the damage to the local economy, wildlife and the ecosystem of the Gulf is hard to fully assess yet.

It's good to think - but not too much, scientists say

17 September 2010

People who think more about whether they are right have more cells in an area of the brain known as the frontal lobes.

UK scientists, writing in Science, looked at how brain size varied depending on how much people thought about decisions.

But a nationwide survey recently found that some people think too much about life.

These people have poorer memories, and they may also be depressed.

Stephen Fleming, a member of the University College London (UCL) team that carried out the research, said: "Imagine you're on a game show such as 'Who Wants to Be a Millionaire' and you're uncertain of your answer. You can use that knowledge to ask the audience, ask for help."

The London group asked 32 volunteers to make difficult decisions. They had to look at two very similar black and grey pictures and say which one had a lighter spot.

They then had to say just how sure they were of their answer, on a scale of one to six. Although it was hard to tell the difference, the pictures were adjusted to make sure that no-one found the task harder than anyone else.

People who were more sure of their answer had more brain cells in the front-most part of the brain - known as the anterior prefrontal cortex.

This part of the brain has been linked to many brain and mental disorders, including autism. Previous studies have looked at how this area functions while people make real time decisions, but not at differences between individuals.

Illness link
The study is the first to show that there are physical differences between people with regards to how big this area is. These size differences relate to how much they think about their own decisions.

The researchers hope that learning more about these types of differences between people may help those with mental illness.

Co-author Dr Rimona Weil, from UCL's Institute of Cognitive Neuroscience, said: "I think it has very important implications for patients with mental ill health who perhaps don't have as much insight into their own disease."

She added that they hope they may be able to improve patients' ability to recognise that they have an illness and to remember to take their medication.

However, thinking a lot about your own thoughts may not be all good.

Cognitive psychologist Dr Tracy Alloway from the University of Stirling, who was not involved in the latest study, said that some people have a tendency to brood too much and this leads to a risk of depression.

More than 1,000 people took part in a nationwide study linking one type of memory - called "working memory" - to mental health.

Working memory involves the ability to remember pieces of information for a short time, but also while you are remembering them, to do something with them.

For example, you might have to keep hold of information about where you saw shapes and colours - and also answer questions on what they looked like. Dr Alloway commented: "I like to describe it as your brain's Post-It note."

Those with poorer working memory, the 10-15% of people who could only remember about two things, were more likely to mull over things and brood too much.

Both groups presented their findings at the British Science Festival, held this year at the University of Aston in Birmingham.

Missing 'cult-like' group found alive after suicide fears

By the CNN Wire Staff
September 19, 2010 -- Updated 2337 GMT (0737 HKT)

Los Angeles, California (CNN) -- A group of 13 Salvadoran immigrants missing in southern California amid fears that they planned a cult-like mass suicide have been found alive, unhurt and upset to find they were the subjects of an extensive search.
Authorities had been scouring the Palmdale area of northern Los Angeles County on horseback and by helicopter Sunday in search of the group, which included eight children between the ages of 3 and 17, said Steve Whitmore, a spokesman for the Los Angeles County Sheriff's Department. A resident spotted one of the vehicles identified in the lookout at a park and notified the sheriff's department, he said.
One woman in the group told CNN they were "perfectly OK" and were shocked and angry to learn that such an extensive search was under way. The woman, who would not give her name, said they had been praying all night in the park, that they had done this routinely and that their husbands were aware of the practice.

The search began Saturday afternoon, when the husbands of two women in the group reported them missing, the Sheriff's Department said. One of the men said their wives were part of a "cult-like group" and had been "brainwashed" by its leader, and Whitmore said the wife left a purse with her husband and asked her "to pray over" it.
When the husband opened the purse, he found money, mobile phones and notes that "talked about meeting Jesus, talked about deceased relatives soon to meet up," Whitmore told CNN earlier Sunday. That raised concerns that the group members planned to take their own lives, he said.
The husbands told investigators that the group had broken away from a Christian church in the Los Angeles area "and formed a separate group that included both traditional and non-traditional practices and beliefs," the Sheriff's Department said Saturday. Its leader, whom investigators identified as Reyna Marisol Chicas, had taken her followers on a similar outing six months ago "in the apparent belief that there was going to be a major earthquake."

Several members of the group spoke with investigators, and Chicas was held for questioning after giving deputies a false name, Whitmore said. Though no crime had been committed and the group appeared to be praying for 'honest and well-meaning things," he said deputies had to investigate once their husbands filed missing persons reports.
"The letters themselves could be interpreted in many ways," Whitmore said. "Now, some of the language in it could be interpreted as saying goodbye as relatives, but that's an interpretation." But given the husbands' concerns, "It is better to overreact than underreact," he said.

Geoengineering 'not a solution' to sea-level rise

By Katia Moskvitch
Science reporter, BBC News

There are many different approaches to geoengineering
Even the most extreme geoengineering approaches will not stop sea levels from rising due to climate change, a study suggests.

New research proposes that as many as 150 million people could be affected as ocean levels increases by 30cm to 70cm by the end of this century.

This could result in flooding of low-lying coastal areas, including some of the world's largest cities.

The team published the study in the journal PNAS.

Scientists led by John Moore from Beijing Normal University, China, write that to combat global warming, people need to concentrate on sharply curbing greenhouse gas emissions and not rely too much on proposed geoengineering methods.

"Substituting geoengineering for greenhouse emission control would be to burden future generations with enormous risk," said Svetlana Jevrejeva of the UK's National Oceanography Centre, a co-author of the study.

Geoengineering has been talked about for countering some of the effects of climate change for the past several years, with some figures like the billionaire Bill Gates ploughing millions of dollars into the research.

But Dr Jevrejeva told BBC News that some proposals such as placing mirrors in space and spraying aerosols - microscopic particles - into the sky would only treat the symptoms, as greenhouse gases would remain in the Earth's atmosphere.

Dr Jevrejeva and her colleagues examined two geoengineering schemes with five different scenarios.

'Not a solution'
The first approach involves limiting incoming solar radiation through the injection of SO2 (sulphur dioxide) aerosols into the stratosphere. Alternatively, giant mirrors could be launched into orbit, they said.

The second approach would involve modifying the carbon cycle by either planting more trees (afforestation), converting organic material into charcoal (biochar) or using renewable energy from materials derived from biological sources (bioenergy).

"We used [a computer model to track] 300 years of tide gauge measurements to reconstruct how sea level responded historically to changes in the amount of heat reaching the Earth from the Sun, the cooling effects of volcanic eruptions, and past human activities," said Dr Jevrejeva.

"We then used this information to simulate sea level under geoengineering schemes over the next 100 years," she added.

The team found that, if taken individually, even the most extreme of these methods would result in severe sea-level rise.

She explained that these scenarios relied on biological mechanisms to remove CO2 from the air and store it in biomass, soils or geological storage sites.

For instance, afforestation, or adding forests to places where they have been cut down or never existed, would lower the amount of atmospheric CO2, but only by 45ppm (parts-per-million) - a lot less than the amount humans have already emitted.

Biochar would reduce the CO2 levels by even less - 35ppm.

Biofuel production would be more effective, and the combination of the three methods could eliminate up to 250ppm of CO2 and limit sea level rise to between 20 and 40cm.

Carbon storage
The carbon storage technique also has other advantages, pointed out Dr Jevrejeva. It actually reduces the amount of CO2 in the atmosphere, whereas the method of reflecting sunlight back into space does not.

"If you use a mirror, it's extremely expensive and it's an engineering challenge - you have to place mirrors [weighing] some 20 million tonnes into the Earth's orbit," Dr Jevrejeva explained.

There was also the chance these mirrors might break in orbit, the researcher added.

The same goes for SO2 aerosol injection - a controversial approach that has already been tested on a small scale in Russia by one of the country's leading climatologists Yuri Israel.

But Dr Jevrejeva said that even though injecting a certain amount of SO2 into the atmosphere might lower mean global temperatures by 1C or more over a few decades, the CO2 would still persist there.

The researchers' simulations showed that spraying the stratosphere with aerosols would produce a similar effect to a major volcanic eruption occuring every 1.5 years. Besides reducing global temperatures, this approach would also delay sea-level rise by 40 to 80 years.

"During a natural volcanic eruption, there's usually a cooling effect in the atmosphere and a drop in sea level. We [followed] different scenarios using the amount of aerosols equivalent to the biggest eruption of the 20th Century - the eruption of Mount Pinatubo in 1991," said Dr Jevrejeva.

"Particles from volcanic ashes end up in the stratosphere and reflect the radiation from the sun, but the same amount of CO2 stays in the atmosphere, so you do not solve the problem."

Also, no one knows the effect such spraying could have on the ecosystem, added the scientist.

"It's a huge challenge, no one knows what could happen."

In the Proceedings of the National Academy of Sciences (PNAS), the scientists wrote that SO2 injection into the atmosphere would likely lead to such undesirable consequences as "disruption in precipitation patterns and stratospheric ozone, and do nothing to avert the continued absorption of CO2 by the global ocean leading to rising acidity and ecosystem damage."

This controversial technique has already been tested in Russia, where scientists led by climatologist Professor Israel sprayed aerosols into the atmosphere from a small aircraft.

Major concerns
Professor Israel told BBC News that a stratospheric layer of SO2 could effectively cool the planet and would be an effective and none-too-expensive way of tackling climate change.

But there are also many opponents of geoengineering techniques, among them former UK chief scientific adviser Sir David King.

He told BBC News about his concerns over geoengineering proposals, especially those involving spraying the stratosphere with aerosols.

"What worries me is that it's cheap and do-able and all you need is a country with a rocket and they can put aerosols up into the stratosphere. We have no confidence in models on what these aerosols would do there.

Sir David explained: "Imagine if the aerosols would in some way cause more aerosol production - because there are a lot of chemicals there including ozone - and in time we find that we're getting more than we anticipated so the planet gets cooler and cooler when we wanted it to be stable"