Friday, May 23, 2008

The carbon catcher

The carbon catcher

Climate science pioneer Wallace Broecker thinks alternative energy would be a 'miracle', and Greenpeace have got it wrong. Instead we must store C02, he tells Ed Pilkington

Wallace Broecker's office looks at first glance what you might expect from the inner sanctum of one of the world's leading geoscientists and oceanographers. There is a giant map of the ocean floor strewn across a desk. A picture of a 19th-century gentleman with a magnificent beard hangs above the mantelpiece; I mistake him for Charles Darwin but am told he is the geologist and explorer, John Strong Newberry.

Closer inspection of the room reveals that it is anything but typical. There's no computer to be seen, while in one corner of the room is a life-sized photograph of Bob Hoskins in Who Framed Roger Rabbit. The other corner houses a 20ft fluffy snake, aqua blue with pink spots and a flashing red tongue. A sign around its head reads: "I am the climate beast and I am hungry."

Broecker, who is universally known as Wally and has done as much as anyone to bring the perils of climate change to the world's attention, sees climate as an animal capable of acting in unpredictable and violent ways. "If you're living with an angry beast, you shouldn't poke it with a sharp stick," he says.

He was among the first, in 1975, to sound the alarm on global warming even as many of his colleagues believed the Earth was cooling down. He can claim credit for the discovery of the conveyor belt flow of the oceans. He showed how the Earth's climate can change abruptly with brutal consequences. And he made seminal discoveries about the crucial links between climate cycles and the fluctuating concentration of atmospheric carbon dioxide.

It's an impressive resumé, all the more so as he accomplished it at the same time as raising six children with his wife, Grace, who died last year.

And, as the strange absence in his office attests, he did it all without the use of a computer. He writes in pencil, and relies on assistants at New York's Columbia University, his base for 55 years, to type up his manuscripts and print out his emails. "I suppose I'm lazy and I'm spoiled," Broecker says. "But it gives me the luxury of thinking. I still maintain that when scientists with all their computers can do better than I can, I'll step aside; but so far I can hold my own."

As the title of Broecker's new book - Fixing Climate: The Story of Climate Science and How to Stop Global Warming - suggests, he has now moved beyond explaining climate change in order to search for a solution. Broecker believes humanity is incapable of weaning itself from fossil fuels. C02 concentrations are already at 380 parts per million (ppm) - up from 280ppm before the industrial revolution, and are rising by more than 2ppm a year. "Some people say we can stop at 450ppm, but that's ludicrous," he says. "It will be hard, very hard, for us to stop at even 600ppm. And if we carry on doing what we are doing now - very little - we are going to get up to 800 or 900ppm. That's really a trip."

Alternative forms of energy, he argues, will fall short. Nuclear brings with it problems of disposal and the fear of weapons. Wind energy is simply too weak. Hydrogen fuel would require a whole new infrastructure to deliver it. Solar is probably the long-term answer but is unlikely to become cheap enough quickly enough to prevent disaster.

That leaves, he argues, a massive gap between the dramatic surge in energy use that will be seen over the next 30 years and the need to lower CO2 levels within the same timeframe. "A lot of people have unrealistic attitudes," he says. "If we put all these alternatives together, they say, we will have a solution. Maybe they are right. But what you see now is China and India adding a whole new element. Suddenly they are using energy like gangbusters, and a lot of it is coal. Too many people look at the rich nations and think we have to cut down, and of course we do, but boy, that's not going to solve the problem."

So we are all doomed? Broecker's book, co-authored with journalist Robert Kunzig, concedes that pessimism is a rational response. But it ends on a high, for Broecker has lent his name to, and to some degree staked his reputation on, a highly controversial new technology that claims to offer a way out of man-made disaster. "We've got to figure out a way to keep the world from being overheated," he says. "If you can't stop more and more C02 being pumped into the atmosphere then we need a safety net capable of solving the whole problem." Broecker, together with a team he helped assemble, believes he has done just that. Their new machine, prosaically called a "scrubber", is intended to suck CO2 out of the open air and capture it, ready to be neutralised or stored where it can no longer cause damage.

Broecker introduced a fellow scientist at Columbia, Klaus Lackner, whom he describes as the "best brain I have ever met", to an engineer called Allen Wright. Together they drew up a prototype scrubbing machine that they say can draw CO2 out of the air - a technique mastered in enclosed spaces such as submarines but never before achieved in the open atmosphere, and generally regarded by scientists and policy makers as impossible. Broecker then introduced the pair to his great friend, the late mail-order clothing tycoon Gary Comer. Comer was a keen sailor who had become aware of the melting ice sheets after he sailed his 151ft yacht straight through the Northwest Passage virtually unencumbered by ice. Alarmed, he tracked down Broecker, flying in his private jet to see him in 2002. The result was a $5m donation that helped pay for the scrubber.

The unlikely arrival of this energetic, can-do businessman had a profound impact on Broecker. The scientist had been contemplating retirement, having survived cancer and heart disease. I ask him whether his illness had any bearing on his approach to global warming. "I'm not very philosophical about things like that," he says. "I had a bone tumour, I was walking on crutches, having night sweats. They gave me chemo and within two weeks it just blew the tumour off. My attitude was: if I survive I survive, if I die I die. I was fatalistic."

Surgery to remove a tumour from his jaw in the 1980s left Broecker's face slightly lopsided, adding to an impression of eccentricity. With his wispy hair, twinkly eyes, and 1970s-style clothes, he comes across as an archetypal mad professor - proudly so. Recently he moved into a state-of-the-art new building in Lamont, Columbia's verdant outpost in New York state. He had to leave the rusty old laboratory he affectionately calls the Pigsty.

The new lab was paid for by Comer's foundation. Broecker's office sits directly over the main entrance, allowing him to pounce on anyone he wants to talk to as they come in - his preferred form of communication, rather than hated email. But the product of his collaboration with Comer that Broecker is most excited about these days is their new machine, stored in a laboratory in Tucson, Arizona. This is the scrubber that Comer paid for, Lackner conceived and Wright built. It deploys a secret new form of plastic which the team says attracts CO2 in a way that allows the gas to be captured, compressed and then safely deposited underground.

Critics regard the very suggestion that there is a way to take CO2 out of the air, reversing fossil-fuel pollution, as sacrilege. Greenpeace has accused the Lackner team of gross irresponsibility, on the grounds that they are condoning more combustion of oil and coal. Broecker is indignant at the suggestion.

"When Greenpeace says we shouldn't capture and bury CO2 because it encourages the use of coal, I say it's not that we are encouraging it. Desperate people who want energy are going to use the coal they have and there's no way in hell that we are going to stop them." But he stresses he doesn't see CO2 capture as a substitute for the search for an alternative source of energy. "If we found the magic bullet to make energy another way we would put this new technology on the shelf. But I happen to think it would take a miracle to find an alternative form of energy in time."

Broecker concedes that a meaningful attack on CO2 levels through scrubbing the air would be a gigantic task involving the whole planet. He points out that if all the CO2 that is likely to be pumped into the air over the next 20 years were captured and liquefied it would fill Lake Michigan. "Every mile you drive an ordinary American car, like the beat-up Toyota I drive, produces 1lb of CO2. That's 20,000lbs a year, just from my car."

In any case, whatever solution to the problem of global warming is preferred by the public and its leaders, it will require extraordinary political will to push it through, and at present that is wholly lacking. I ask him how big he thinks the gulf is between the challenge ahead and the political determination to face it. "Huge, huge," is his reply.

The three candidates for the White House have all campaigned around the issue of global warming, though none has yet approached him for advice. But Broecker is sceptical that the next president will move fast enough.

"It's easy to talk about tackling this in a campaign, because they don't have to face the financial pain. But when they get into office they will feel the reality - if they make it too painful they will be kicked out."

The climate is a beast, don't poke it. A superstitious person would swear blind that as we finish our conversation the snake at Broecker's feet slithered a little and shook its tongue. But this is science. That never happened.

· Fixing Climate: The Story of Climate Science - and How to Stop Global Warming, by Robert Kunzig and Wallace Broecker, is published by Profile Books on June 2. To order a copy for £9.99 go to guardian.co.uk/bookshop or call 0870 835 0875. Both authors are at the Guardian Hay Festival on May 31. Box office 0870 990 1299

Sealife at risk from rapid acidification

· Increased CO2 levels to blame, say experts
· Catastrophic impact on marine ecology predicted

Floreana coral

Floreana coral, which is listed as critically endangered. Photograph: Paul Humann/PA

Scientists conducting a major survey of the North American Pacific coast have found significant increases in acidity that could have a profound effect on sealife.

Rising ocean acidity has been predicted by scientists as a consequence of increased CO2 emissions, but the new research suggests that in some parts of the ocean these increases are happening much faster than predicted. The change seen in the surveys was not expected until 2050.

Experts predict that the changes could have a catastrophic effect on marine life. More acidic seawater means that species such as shellfish, plankton and coral will have much more difficulty making their shells and hard skeletons. That will seriously reduce the productivity of the entire food chain, changing ocean ecology and leading potentially to drastic reductions in fish stocks.

"It's very worrying," said Dr Carol Turley, at Plymouth Marine Laboratory. "The marine food web is extremely complex so [the effects are] very hard to predict. Whether it will support the kind of food web we are used to seeing and depending on in future is anyone's guess really."

She was an author of a major report from the Royal Society in 2005 on ocean acidification. It predicted that the impact would go beyond marine ecosystems and fisheries. "The socioeconomic effects of ocean acidification could be substantial. Damage to coral reef ecosystems and the fisheries and recreation industries that depend on them could amount to economic losses of many billions of dollars per year," the authors wrote.

The Intergovernmental Panel on Climate Change also flagged up ocean acidification as a problem in its fourth assessment report in 2007. It said that human carbon emissions had already reduced average ocean pH by 0.1 units. By 2100 pH could fall by a further 0.5, equivalent to a tripling of the concentration of hydrogen ions.

Higher greenhouse gas emissions lead to more acid seas because around half the CO2 humans produce is soaked up by the oceans. Here it forms carbonic acid, altering the ocean chemistry and making carbonate ions less available to hard-shelled marine creatures. In the new research, Richard Feeley at the US government agency the National Oceanographic and Atmospheric Administration and his colleagues sampled ocean chemistry along 13 survey lines stretching from central Canada to northern Mexico. They found acidic water much closer to the surface than expected. The results are reported today in the journal Science.

"This upwelling water is going to intermittently - once a year or so - flood in for a number of months into our productive shallow seas," said Turley. This would be corrosive to some marine creatures, she said, in effect dissolving the calcium carbonate in their shells.

That does not mean that species will immediately die, but it does mean they have to use huge amounts of energy just to maintain their shells.

The great concern for scientists is the speed at which the changes are happening. "What it does indicate is that [marine species] may not have time to adapt as we might have hoped for," said Turley.

SUVs plunge toward 'endangered' list

  • Story Highlights
  • Car dealer says SUVs are tough sells now: "I've never seen it this bad -- ever"
  • AAA says average gas price hit another all-time high Friday
  • Truck owner says he can't get the price he wants for his vehicle

LOS ANGELES, California (CNN) -- Jorge Fernandez strolls across the used-car parking lot littered with dozens upon dozens of sport utility vehicles the size of small tugboats.

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With gas at $4 a gallon, many have sat there since last summer.

"The cars are literally just sitting, and it doesn't matter how much you sell them for," Fernandez says of the SUVs and trucks nobody wants anymore.

"It's amazing. I've never seen it this bad -- ever."

Fernandez, a wholesale auto dealer who has been in the business for more than 20 years, says SUV owners are hit especially hard. The really large ones with V-8 engines that can get as little as 12 miles per gallon in the city -- like the Cadillac Escalade, Ford Expedition and Chevy Suburban -- are dropping in value by the thousands. Video Watch the sinking value of guzzlers »

The No. 1 reason for the sales slump is soaring gas prices, says Peter Brown, the executive director of Automotive News, the trade newspaper for the North American car industry.

For the first four months of this year, truck and SUV sales are down a collective 24.8 percent. SUV sales plummeted 32.8 percent while pickups dipped 19.9 percent, he says.

"If gas prices stay where they are at or continue to rise, the body-on frame SUV is an endangered species and the pickup truck as a personal car is an endangered species," Brown says.

How do owners react when they're told their once-$40,000-plus vehicles are now worth less than half that?

"When they find out what you think their truck is worth, they think you're trying to rip them off or something," says Fernandez. "Small cars are gone within a week; SUVs are sitting here since last summer."

David Lavi, the owner of a Toyota Tacoma pickup, is feeling that pinch. He put his truck on the market several weeks ago in hopes of downsizing. He bought it brand new in 2006 when gas prices were much lower.

"Once I do sell it, I'm going to get a smaller car -- maybe a Nissan Maxima or something smaller," he says.

He's hoping to get $23,000 for the fully loaded truck, which is higher than the estimated Kelley Blue Book value of $15,000 to $19,000 depending on how many amenities it has.

"No one has offered what I want," he says.

Automakers have noticed this trend to downsize.

Ford announced Thursday it was shifting production away from its longtime hallmark of pickups and SUVs in favor of smaller cars.

In making the decision, Ford said it believes gas prices will remain in the range of $3.75 to $4.25 a gallon through the end of 2009.

"We saw a real change in the industry demand in pickups and SUVs in the first two weeks of May," Ford chief executive Alan Mulally said Thursday. "It seems to us we reached a tipping point."

Brown of Automotive News said he wouldn't be surprised if General Motors and other automakers follow suit.

According to AAA, gas prices reached another all-time high Friday, with the national average price for a gallon of regular unleaded gasoline at $3.87. Seven states are now over $4 a gallon, AAA says.

Stories of owners ditching larger vehicles for smaller ones have started to become widespread. Owners say they're tired of spending as much as 80 to 100 bucks to fill up their tanks.

Some CNN.com users recently shared their stories of buying used Geo Metros -- the oft-maligned, snail-sized car from the 1990s that gets gas mileage similar to a hybrid of today for a fraction of the sticker price.

"I used to be a car snob, and I used to be too vain to drive anything that doesn't shine," said Marci Solomon, an electrician who has a 100-mile commute to and from work. "But now it's about, do I want to eat, or do I want to make it to work? I want to do both."

But some auto experts caution owners against trading in their SUVs and trucks to save money at the pump because it may not be the wisest financial decision.

Owners might owe $20,000 or more when the vehicle is now worth $12,000. It's similar to an upside-down mortgage, and it may not make sense to try a trade-in.

"What they might be doing is spending thousands of dollars to save hundreds," says Jack Nerad, the executive director of Kelley Blue Book's kbb.com.

"Because if you make a trade, you're most often going to spend more to make that move than you would just sucking it up and paying the extra gasoline prices."

Back at the Los Angeles lot, Fernandez says he thinks the trend away from SUVs and pickups is here to stay.

"Just when you think that it's going to change any day now, it doesn't. It just continuously gets worse," he said.

The high cost of oil is bad for the economy, but is it good for the climate?

Several theories were emerging yesterday over the environmental effects of oil at $130 a barrel or more. In the green corner were the optimists, who believe that the shock will force people to cut their energy use, invest in renewables and energy conservation, downsize their cars, take fewer foreign holidays and reduce greenhouse gas emissions

Others fear that oil prices at this level for any length of time will usher in a new bleak period where governments turn to extracting coal, growing biofuels and deforestation.

There was evidence of both trends yesterday. As Honda announced it was increasing output of its hybrid cars because of high fuel prices, Barrie Johnstone, chief executive of Solartwin.com said inquiries about his company's solar panels to heat water had risen by more than 50% in five months.

"The oil price rises change the payback period dramatically. Anyone who buys solar equipment now has probably paid off the investment at the moment he buys it. High oil prices like this are good for us but no one else."

"These prices are already proving to be the biggest single factor in curtailing the expansion of the aviation industry, and that wont necessarily be a bad thing," said Ben Stewart, communications director at Greenpeace. "One hopes it will lead to a huge investment in alternative sources of energy. We are moving into the unknown. As prices increase, it will just have to lead to the investment that we so desperately need."

Tom Burke, environmental scientist and visiting professor at Imperial College London, said that in the short term the oil price rise would cause a rush to exploit oil tar sands in Canada and Venezuela, and possibly deforestation in the Amazon to clear space for biofuels.

"We have passed the peak of cheap oil. I do not think it will slow down Indian and Chinese vehicle use. It will really hit the aviation industry and could cut the ground under the push for the third runway at Heathrow. It could also strengthen the localisation movement." The majority of companies, he said, had already done a lot already to reduce their energy use.

Environmental consultant and former -director of Friends of the Earth Charles Secrett said the lesson of history in high oil prices was that it was an opportunity for change. "In the years after the 1973 oil shock, energy efficiency soared, but governments did not step in with policies to encourage alternatives energies to flourish. They have the real choice now."

In the short term, the oil price rise is expected to cause further increases in the price of fertilisers, which doubled last year as US farmers rushed to put as much on fields as possible to take advantage of high prices for biofuel crops. But in poor countries the more expensive fertilisers are likely to be beyond the means of most small farmers. This could reduce farm yields and incomes, and result in more deforestation as people turn to any source of income they can.

"This is a wake-up call. In the short term we can already see people in the US cutting down on their driving, starting to use public transport and not buying SUVs. But in the long term it means that we have to completely rethink how we use energy", said Walt Patterson, a fellow in the sustainable development programme at Chatham House in London.

The war to end all wars

The climate change threat needs drastic action. Only a cross-party approach can deliver it

How do you define a war? There is the disastrous one that Britain is waging in Iraq, involving tanks and guns and the lives of our young men and women. There is the kind the government claims it is waging variously against poverty, terror, and obesity. But the greatest threat to us all, global warming - a threat far greater than any airborne disease or foreign dictator - has yet to be elevated to war status. Day by day, before our eyes, the planet is deteriorating: ice caps are melting, weather systems shifting, and the poorest are finding themselves facing life-threatening water shortages. Our wildlife is suffering, species are being lost before our children even have a chance to witness them in all their beauty.

Britain, with 174 other countries, signed up to the Kyoto protocol, but while the government has made great political play of the fact that greenhouse gas emissions have decreased over the past decade, actual CO2 emissions have gone up. The only cuts that have been made have come from small, one-off technical fixes of things like landfill gas methane emissions. Labour might have great plans for cutting climate-changing gases, but most of its policies, from motorway widening to new runways, point in the opposite direction, and are actually worsening the situation.

As a group, some concerned mothers - myself among them- are coming together with their children this week because we want to leave our planet in much the same way as it was when we were born: rich, varied and able to support and feed us all. All across Britain, families are recycling waste, cutting back car use and giving up using plastic bags. But we know we are long past the time for small-time individual action - we need to direct a transition to a low-carbon economy. The government still seems to be terrified of motorists, frequent flyers and second home-owners, and is far too timid to take any measures that begin to address the scale of the problem. The targets in the climate-change bill are a good start, but there is no policy framework to actually achieve them - it is no good politicians saying each year, "Sorry, we failed", as the world fries. The climate crisis must be our pre-eminent policy priority.

As the environmentalist Mark Lynas says: "We must peak global emissions by 2015 if we are to keep temperatures from rising beyond two degrees - after which point total climate catastrophe beckons, and that means international policy must be finalised by Copenhagen in 2009. The British government will have no political capital to demand cuts in countries like China when it is overseeing more coal-fired power stations and rising CO2 emissions at home."

Last week MPs tabled a motion calling for immediate cross-party action on climate change. Their move comes as we launch a new campaign aimed at forcing the government to take the lead on tackling global warming. For many of those involved, it will be the first time they have taken political action. We call ourselves We Can (Can standing for Climate Action Now), and tonight we'll be holding a candle-lit protest outside the House of Commons. During the evening, the children will deliver a letter to No 10 for Gordon Brown: it's their future at stake here, not ours.

Climate change is too vital an issue to sacrifice to political infighting and cowardice. Clearly, it would be political suicide for any one party to introduce the changes needed, which is why a cross-party coalition should be formed (as during the second world war) to guide and direct both government planning and industry direction.

If his budget speech to the Commons is to be believed, Alistair Darling has made up his mind: climate change is the greatest challenge facing us all, and "there will be catastrophic economic and social consequences if we fail to act". In response to this, with great determination and steely efficiency, the chancellor has utterly failed to act.

After the Japanese bombed Pearl Harbour in 1941, the US threw its might behind the war machine, transforming its industries overnight. The bounties of my entire life as a postwar baby have come as a direct result of that giant political will bending towards the common good. Now my daughter's generation demands the same drastic intervention if they are to enjoy the same kind of future.

It can be done and we know the enemy. But where, on our increasingly fragile earth, is the leadership?

· Rosie Boycott is a writer and broadcaster wecan.uk.com

Sunday, May 18, 2008

Conservationists lament departure of Brazilian minister

From: WWF

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The sudden resignation of Brazilian Environment Minister on 13 May has been greeted with shock and regret by the conservationist community.

“This is a clear sign that environmental issues are not in the agenda of the government”, said Denise Hamú, WWF-Brazil’s Secretary General.

“Since Marina Silva took office in January 2003, she was counteracted and discredited by the Federal Government”, said Hamú. “Examples include during the debates on genetically modified organisms (GMOs), alternatives for agri-business and especially the process to license hydroelectric dams on the Madeira River in the Amazon.”

WWF-Brazil paid tribute to significant progress in the environmental field achieved during Minister Silva’s office. Among others: the forestry policy to grant forest concessions, measures to monitor, prevent and fight deforestation, the creation of the Chico Mendes Institute for Biodiversity Conservation (ICMBio) to manage federal protected area sites; efforts for the approval of the Atlantic Forest Law in the Congress, and the creation of the Brazilian Forestry Service.

According to Denise Hamú, the minister’s resignation is generating much insecurity towards the future.

“She tried in vain to build a sustainable development policy that involved all ministries and not just her own.

Another factor that, according to WWF-Brazil, contributed to the Minister’s resignation was President Lula’s recent decision not to delegate to her the coordination of the Sustainable Amazon Plan launched earlier in May.

For WWF-Brazil’s Secretary General, the resignation of Marina Silva is also a great loss, because of her background. She was born in a village in a remote area of the Amazon region, has strong links with the social movement and has been very active in environmental defence during her whole political career.

“Marina Silva’s resignation will have international repercussions for Brazil, and the only positive aspect is that we will have an excellent senator back”, said Hamú.

The politician was re-elected senator in 2002 for the State of Acre and her terms ends in 2010.

On the same day Marina Silva resigned, some 200 farmers, forest product workers and fishermen participated in a public hearing in the House of Representatives on the delay caused by defining the status of protected area sites.

And on May 13 also, a demonstration was held in front of the National Congress with the objective to put the Federal Government under pressure so as to accelerate the creation of extractive reserves in the northern, northeaster and Midwestern regions of the country.

Nanostructures Will Raise Thin-Film Solar Cell Efficiency

From: University of California, San Diego

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Thanks to nanostructures that scatter and channel light, University of California, San Diego electrical engineers are working toward thin-film “single junction” solar cells with the potential for nearly 45 percent sunlight-to-electricity conversion efficiencies. This effort to break the theoretical limit of 31 percent efficiency for conventional single junction cells recently received a big funding boost from the U.S. Department of Energy’s Solar America program.

In November 2007, a team of Jacobs School electrical engineers led by professor Edward Yu won an $885,000 grant from the U.S. DOE to further develop their thin-film and nanowire solar cell devices that incorporate nanostructures, including semiconductor quantum wells and photon-scattering nanoparticles.

The new devices could lead to big gains in thin-film solar cell efficiency by increasing both the number of photons thin-film solar cells absorb and the number of excited electrons the same devices collect.

“The most recent estimate of the maximum power conversion efficiency — under normal illumination conditions — that one can expect with our new thin-film solar cell approach is approximately 45 percent. This is a very large improvement over the 31 percent maximum theoretical efficiency for today’s solar cells with classic p-n junctions,” said Edward Yu, the Principal Investigator on the three-year DOE grant.

Electrical engineering professors Paul Yu and Deli Wang are co-PIs on the project.

From the outside, the optimized devices behave just like traditional thin-film solar cells. But inside, the nanostructures enable the solar cells to circumvent an important tradeoff that has stymied past attempts to incorporate quantum wells into thin-film solar cells in order to boost device efficiency. Quantum wells can increase solar cell efficiency by raising photon absorption by lowering the energy band gap.

In the past, engineers have tried to add quantum wells to thin-film solar cell devices by stacking several quantum-well layers to achieve a high probability of absorption of low-energy photons. This approach, however, can be counter productive because electron-hole pairs get stuck in the quantum wells, making it impossible for them to generate current for the device.

The UC San Diego engineers are using nanoparticles to scatter incoming light into paths within the quantum well region — paths that run parallel to the p-n junction. This gives photons more time to be absorbed without having to stack the quantum wells to a thickness that makes it hard for electrons and holes to escape.

“Our devices have a much thinner stack of quantum wells, which means the extra photons that are absorbed are much more likely to make it out of the quantum wells and generate current,” explained Edward Yu. “This enables high photon absorption efficiency, high electron and hole collection efficiency — and therefore also high voltage — to be achieved simultaneously.”

In the UCSD approach, the photons are provided with a long path along the quantum wells and the carriers have a short path to the electrode. This design maximizes photon absorption while minimizing a major drain on device efficiency in solar cells — electron-hole recombination.

“We have already demonstrated the basic concepts in thin-film devices. I think it will take a few years to see how far this approach can be pushed to achieve really high efficiency because there are many aspects that have yet to be optimized,” said Yu.

Expert warns climate change will lead to 'barbarisation'

This article was first published on guardian.co.uk on Thursday May 15 2008.

Climate change will lead to a "fortress world" in which the rich lock themselves away in gated communities and the poor must fend for themselves in shattered environments, unless governments act quickly to curb greenhouse gas emissions, according to the vice-president of the intergovernmental panel on climate change (IPCC).

Mohan Munasinghe was giving a lecture at Cambridge University in which he presented a dystopic possible future world in which social problems are made much worse by the environmental consequences of rising greenhouse gas emissions. "Climate change is, or could be, the additional factor which will exacerbate the existing problems of poverty, environmental degradation, social polarisation and terrorism and it could lead to a very chaotic situation," he said.

The scenario, which he termed "barbarisation" was already beginning to happen, he said. "Fortress world is a situation where the rich live in enclaves, protected, and the poor live outside in unsustainable conditions.

"If you see what is going on in some of the gated communities in some countries you do find that rich people live in those kind of protected environments. If you see the restrictions on international travel you see the beginnings of the fortress world syndrome even in entering and leaving countries," he said.

The Sri Lankan-born expert on climate change and sustainable development was delivering the annual Clare College Distinguished Lecture in Economics and Public Policy. He said the IPCC's fourth assessment in 2007 predicted that developing countries would be hit hardest by climate change, especially rising sea levels.

"One of the most distressing aspects is that developing countries are the most vulnerable to climate change and the poorest people will be the hardest hit. This is in fact rather unfair because they had least to do with the problem – apparently they will pay the biggest costs," he said.

Bangladesh, for example, could lose 17% of its land – mostly highly populated areas – to rising seas, according to Munasinghe. But, he was positive about international efforts to tackle the problem. "I tend to be optimistic because I believe this can be done through rational processes, but I also feel that the consequences of failure are unimaginable and that's really the bottom line."

Exxon facing shareholder revolt over approach to climate change

This article was first published on guardian.co.uk on Monday May 19 2008.

A shareholder revolt at ExxonMobil led by the billionaire Rockefeller family has won the support of four significant British institutional investors who will call on Monday for a shake-up in the governance of the world's biggest oil company.

The Guardian has learned that F&C Asset Management, Morley Fund Management, the Co-Operative Insurance Society and the West Midlands Pension Fund are throwing their weight behind a resolution demanding that ExxonMobil appoints an independent chairman to stimulate debate on the company's board.

Exxon is facing a rebellion from its investors over its hardline approach to global warming. The firm has refused to follow rival oil companies in committing large-scale capital investment to environmentally friendly technology such as wind and solar power.

The Rockefeller dynasty, whose ancestor John D Rockefeller founded the original oil business at the core of ExxonMobil, have sponsored four shareholder resolutions demanding changes at Exxon. One of these calls on Exxon's chief executive Rex Tillerson, to relinquish his role as chairman in favour of an outsider to bring in an alternative point of view.

The London-based corporate governance advisory service Pirc intends to recommend that institutions support this proposal, which is in line with best practice on corporate boards in the UK.

F&C Asset Management's director of governance and sustainable investment, Kevin Litvack, said it could pave the way for a different attitude at Exxon towards the environment.

"Despite top-notch individual directors, the company's record over the last decade, particularly regarding climate change, demonstrates that debate has been lacking," said Litvack. "By bringing in an independent chairman, the company can better leverage that creativity and challenge, and avoid over-dominance by management."

Exxon maintains that present green technologies are not financially viable. But critics on Wall Street and in the City fear that the company's reluctance to explore alternative energy will prove to be bad business judgement in the long run as rivals such as BP seek to capture public affection by re-branding themselves as environmentally sensitive enterprises.

The Rockefellers point out that Exxon has $25bn of capital investment planned in carbon-based fuel but its environmental commitment is centred a relatively modest $100m to fund a Stanford University project on climate change.

If the rebellion continues to gather pace, Exxon could suffer an embarrassing defeat at its annual meeting in Dallas later this month. At last year's meeting, 40% of investors' votes were cast in favour of a similar call for an independent chairman and the Rockefellers' involvement this time has raised the profile of the battle.

In the US, three advisory firms – RiskMetrics, Glass Lewis and Proxy Governance – have urged fund managers to support the Rockefellers' resolution. The result of the vote is not binding on Exxon but the company has said that its board will reconsider any of its policies challenged by successful shareholder resolutions.

An Exxon spokesman last night responded to the British institutions' stance by re-asserting the company's position that its board is better placed than investors to decide on the leadership structure.

In a written response to the shareholder resolutions earlier this month, Exxon said its board members possesses "considerable experience and unique knowledge of the challengers and opportunities the company faces".

World's wildlife and environment already hit by climate change, major study shows

· 90% of damage caused by rising temperatures
· Conclusions based on reports going back to 1970

This article appeared in the Guardian on Thursday May 15 2008 on p17 of the UK news section.
Polar bears in the Arctic National Wildlife Refuge in Alaska

Polar bears have been severely affected by global warming, which a major study has linked to human activity. Photograph: AP

Global warming is disrupting wildlife and the environment on every continent, according to an unprecedented study that reveals the extent to which climate change is already affecting the world's ecosystems.

Scientists examined published reports dating back to 1970 and found that at least 90% of environmental damage and disruption around the world could be explained by rising temperatures driven by human activity.

Big falls in Antarctic penguin populations, fewer fish in African lakes, shifts in American river flows and earlier flowering and bird migrations in Europe are all likely to be driven by global warming, the study found.

The team of experts, including members of the UN's intergovernmental panel on climate change (IPCC) from America, Europe, Australia and China, is the first to formally link some of the most dramatic changes to the world's wildlife and habitats with human-induced climate change.

In the study, which appears in the journal Nature, researchers analysed reports highlighting changes in populations or behaviour of 28,800 animal and plant species. They examined a further 829 reports that focused on different environmental effects, including surging rivers, retreating glaciers and shifting forests, across the seven continents.

To work out how much - or if at all - global warming played a role, the scientists next checked historical records to see what impact natural variations in local climate, deforestation and changes in land use might have on the ecosystems and species that live there.

In 90% of cases the shifts in wildlife behaviour and populations could only be explained by global warming, while 95% of environmental changes, such as melting permafrost, retreating glaciers and changes in river flows were consistent with rising temperatures.

"When we look at all these impacts together, it is clear they are across continents and endemic. We're getting a sense that climate change is already changing the way the world works," said lead author Cynthia Rosenzweig, head of the climate impacts group at Nasa's Goddard Institute for Space Studies in New York.

Most of the reports examined by the team were published between 1970 and 2004, during which time global average temperatures rose by around 0.6C. The latest report from the IPCC suggests the world is likely to warm between 2C and 6C by the end of the century.

"When you look at a map of the world and see where these changes are already happening, and how many species and systems are already responding to climate change after only a 0.6C rise, it just heightens our concerns for the future," Rosenzweig said. "It's clear we have to adapt to climate change as well as try to mitigate it. It's real and it's happening now."

A large number of the studies included in the team's analysis reveal stark changes in water availability as the world gets warmer. In many regions snow and ice melts earlier in the year, driving up spring water levels in rivers and lakes, with droughts following in the summer. Understanding shifts in water availability will have a big impact on water management and be critical to securing supplies, the scientists say.

By collecting disparate reports on wildlife and ecosystems, it is possible to see how disruption to one part of the environment has knock-on effects elsewhere. In one study rising temperatures caused sea ice in Antarctica to vanish, prompting an 85% fall in the krill population. A separate study found that the population of Emperor penguins, which feed on krill in the same region, had also fallen by 50% during one warm winter.

A loss of krill, also a dietary staple for whales and seals, was cited as a factor in recent accounts of cannibalism among polar bears in the Arctic. In 2006 Steven Amstrup, a world expert in polar bears at the US Geological Society, investigated three cases of the animals preying on one another in the southern Beaufort sea. A lack of their usual prey may have prompted the bears to turn on each other.

Other reports show how the early arrival of spring in Europe has far-reaching effects down the food chain. The warmer weather causes trees to unfurl their leaves earlier, which causes a rise in leaf-eating grub numbers sooner in the year. Blue tits that feed on the grubs have largely adapted to the shift, by giving birth to their young two weeks earlier.

"It was a real challenge to separate the influence of human-caused temperature increases from natural climate variations or other confounding factors, such as land-use changes or pollution," said David Karoly, a co-author based at Melbourne University in Australia.

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