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26 Sep 07
Lovelock urges ocean climate fix
By Richard Black Environment correspondent, BBC News website
National Geographic News 26 Sep 07
Giant Ocean Tubes Proposed as Global Warming Fix
Yahoo News 26 Sep 07
Global Warming Fix: Help the Earth Cure Itself
Andrea Thompson LiveScience Staff Writer LiveScience.com
Add a new one to the list of somewhat zany suggestions to counteract global warming, only this time the idea comes from the Gaia guy. James Lovelock, environmentalist, futurologist and creator of the Gaia hypothesis and its view of Earth as a huge organism, proposes that we help the planet "cure itself" by artificially ramping up ocean mixing, which would stimulate the growth of carbon-munching algae, thereby sinking more carbon dioxide into the ocean.
The Gaia hypothesis looks at Earth as a whole instead of at each of its systems separately—viewing it as something of a superorganism. "I regard the Earth as a responsive, self-regulating system," Lovelock said, one which should be able to cure itself from any climactic calamities, as it has done in the past.
But human activities have knocked the system out of whack, as increasing amounts of greenhouse gases in the atmosphere raise Earth's average temperature, which in turn contributes to increased melting at the poles, sea level rise and other potentially disastrous consequences.
While some think that we still have time to stem the tide of rising carbon dioxide levels, Lovelock is less optimistic. "I think we are almost certainly past any point of no return, and that global warming is irreversible, almost regardless of what we do in the conventional things, like following the Kyoto Protocol," he said.
Switching to cleaner energy sources and implementing strategies to mitigate global warming, such as carbon sequestration, would take too long to get into gear and would require an impossible level of global cooperation, he said.
Instead, he thinks that we need to give the Earth a way to help cure itself.
If we did nothing at all to counteract the effects of global warming, the Earth would eventually cure itself of global warming, pollution and other ills without any help from us, but that would take many hundreds of thousands of years.
"In the past there have been many hot spells when the Earth heated up as much as we think it will as a consequence of global warming—the last one was 55 million years ago. And it recovered spontaneously, but it took a long time to do it," Lovelock told LiveScience.
Recent estimates by a scientist at Texas Tech University say that the United States alone must cut its emissions by at least 80 percent below 2000 levels by 2050 to avoid a large increase in global temperatures in the coming decades.
"So what we were trying to do here is to stimulate it to enter the recovery phase quickly," Lovelock said. Lovelock's proposal, detailed in the Sept. 27 issue of the journal Nature, is to use free-floating or tethered pipes to increase the mixing of the ocean by moving nutrient-rich deep waters up to replace the more barren waters of the surface. These nutrients would stimulate the growth of algae and create large blooms that would take up carbon dioxide from the atmosphere as they photosynthesize.
"And when they die, their bodies sink to the bottom of the ocean as calcium carbonate shells, and that gets rid of [the carbon] for good," Lovelock explained.
Lovelock's unusual idea joins a growing list of TK proposals to combat global warming that include:
Constructing a "sun shade" by creating an artificial ring of small particles or spacecraft that would block some of the sun's rays from hitting the Earth, thereby reducing heating
Shooting sulfur into the air to reflect incoming solar radiation back to space (volcanoes do this naturally when they erupt)
Making airplane flights longer by requiring planes to fly at lower altitudes, which could reduce the formation of heat-trapping contrails
Injecting carbon dioxide into wet, porous rocks deep underground to store it there for thousands of years, a process known as carbon sequestration
Or dumping iron into the ocean, also to stimulate the growth of algae, in the hopes the blooms will act as a major carbon sink.
While some scientists doubt the feasibility of many of these proposals, Lovelock says that they would probably work, but ultimately wouldn't solve the problem because they are cases of humans curing the Earth, instead of allowing it to cure itself.
"It's not going to do a lot more than buy you time," he said, all the while allowing people to continue emitting carbon dioxide.
And though his proposal has similar results to the so-called iron fertilization experiments, Lovelock sees two key differences: "[Piping up nutrients] would be continuous. With iron fertilization, you have to keep on going out and spreading the iron," he said. "And also, this would bring all the nutrients up, not just the iron."
Will it work?
Lovelock also sees other benefits to his proposal. Because the ocean's deep water is cooler than the surface waters, the pipes could also be beneficial in regions that are at high risk for severe hurricane strikes, such as the Gulf of Mexico, Lovelock added, since hurricanes feed on warm surface waters.
Ken Caldeira, an ocean ecologist at Stanford University, says he has more confidence in the likelihood that this aspect of Lovelock's proposal could work than in its efficacy as a carbon sink.
"That will produce some cooling, at least for awhile, until you heat up that whole surface layer," he told LiveScience.
Another benefit of the proposal, as Lovelock sees it, is that it does not require a large, globally-coordinated effort, like many other proposals would. "If it works, it's not that huge a project," Lovelock said. "Something on the order of 10 to 100,000 of these pipes would do quite a lot."
Lovelock envisions that the pipes would be about 100 to 200 meters long and about 10 meters in diameter, with a flap at the bottom that will use the motion of the waves to pump water up. (Other groups, including the private company Atmocean and Stephen Salter of the University of Edinburgh have proposed similar structures that use slightly different engineering approaches.)
Lovelock doesn't think that the proposal should be jumped on immediately, but that experiments should be done to test the scientific, economic and engineering viability of the proposal.
"I wouldn't attempt to cure the Earth tomorrow, so to speak," he said. Instead, he advocates a small-scale project to test out the pipes on a small island in the tropics that has coral reef in danger of bleaching. If the reef gets better over time after the pipes are put in, the project can proceed to a larger reef, such as the Great Barrier Reef in Australia, then perhaps move to the Gulf of Mexico, all the while ironing out the kinks at each stage.
Weighing pros and cons
Lovelock acknowledges that the pipes could have negative effects, such as ocean acidification—the more carbon dioxide that is added to the ocean, the more acidic it becomes, possibly endangering marine life.
Caldeira points out another possible kink in the proposal: as phytoplankton die and sink down into the ocean, the nutrients and carbon they contain tend to go back into solution in the ocean. "And so more or less, the carbon that you're bringing up in your pipes will balance the carbon that's sinking down," he said. "I think it's unlikely to be very effective as a carbon storage approach."
And even if it does work, it is unlikely to be effective as a widespread approach, sobringing down carbon emissions is still the key to solving the global warming problem, Caldeira said.
Lovelock says these effects need to be investigated in experiments, but adds that what might be bad for one particular area or organism could be good for the planet as a whole.
He likens it to the treatments for serious human diseases that can often make a person sick, but are necessary to beat a more serious ailment (using chemotherapy to treat cancer, for example).
"If we have a treatment for something fairly serious, there'll almost certainly be side effects, and you have to balance the consequences of the benefits and the loss," he said.
Caldeira says that despite the potential problems and questions of efficacy, proposals like this should definitely be investigated, "because there's basically little risk, if you threw one of these out in the ocean."
Essentially, he says, we need to consider any ideas that might help, and weed out the bad from the good.
BBC 26 Sep 07
Lovelock urges ocean climate fix
By Richard Black Environment correspondent, BBC News website
Two of Britain's leading environmental thinkers say it is time to develop a quick technical fix for climate change. Writing in the journal Nature, Science Museum head Chris Rapley and Gaia theorist James Lovelock suggest looking at boosting ocean take-up of CO2.
Their idea, already being investigated by a US firm, involves huge flotillas of vertical pipes in the tropical seas.
The two scientists say they doubt that existing plans for curbing carbon emissions can work quickly enough. "We are taking the very strong line that we are not going to save the planet by the regular approaches like the Kyoto Protocol or renewable energy," Professor Lovelock told BBC News. "What we have to do is to look at it in a systems sense, or a Gaian sense, and see if it's curable by direct action."
Professor Rapley, who has just moved to head up the Science Museum from a similar post at the British Antarctic survey, said the two men developed the ocean pipes concept during country walks in James Lovelock's beloved Devon.
Unbeknown to them, a US company, Atmocean, had already begun trials of a very similar technology. Floating pipes reaching down from the top of the ocean into colder water below move up and down with the swell. As the pipe moves down, cold water flows up and out onto the ocean surface. A simple valve blocks any downward flow when the pipe is moving upwards.
Colder water is more "productive" - it contains more life, and so in principle can absorb more carbon.
One of the life-forms that might benefit, Atmocean believes, is the salp, a tiny tube which excretes carbon in its solid faecal pellets, which descend to the ocean floor, perhaps storing the carbon away for millennia.
Atmocean CEO Phil Kithil has calculated that deploying about 134 million pipes could potentially sequester about one-third of the carbon dioxide produced by human activities each year.
But he acknowledges that research is in the early stages. "There is much yet to be learned," he told BBC News. "We need not only to move towards the final design and size (of the pipes), but also to characterise the ecological effects.
"The problem we would be most concerned about would be acidification. We're bringing up higher levels of CO2 along with the nutrients, so it all has to be analysed as to the net carbon balance and the net carbon flux."
Atmocean deployed experimental tubes earlier this year and gathered engineering data. The pipes brought cold water to the surface from a depth of 200m, but no research has yet been done on whether this approach has any net impact on greenhouse gas levels.
The company says a further advantage of cooling surface waters in regions such as the Gulf of Mexico could be a reduction in the number of hurricanes, which need warm water in order to form.
And Professors Lovelock and Rapley suggest that the ocean pipes could also stimulate growth of algae that produce dimethyl sulphide (DMS), a chemical which helps clouds form above the ocean, reflecting sunlight away from the Earth's surface and bringing a further cooling.
In recent years, scientists have developed a wide range of technical "geo-engineering" ideas for curbing global warming. Seeding the ocean with iron filings to stimulate plankton growth, putting sunshades in space, and firing sulphate aerosols into the atmosphere from a giant cannon have all been proposed; the iron filings idea has been extensively tested.
But the whole idea of pursuing these "technical fixes" is controversial.
"One has to understand what the consequences of doing these things are," commented Ken Caldeira from the Carnegie Institution at Stanford University in California, who has published a number of analyses of geo-engineering technologies.
"There are scientific questions of safety and efficacy; then there are the broader ethical, social and political dimensions, and one of the most disturbing is that if people start getting the idea that technical fixes are available and cheaper than curbing carbon emissions, then people might start relying on them as an alternative to curbing emissions.
"So I think it's worth investigating these kinds of ideas, but premature to start deploying them."
Chris Rapley does not believe ideas like the ocean pipes are complete answers to man-made global warming, but may buy time while society develops a more comprehensive response.
"It's encouraging to see how much serious effort is going into technical attempts to reduce carbon emissions, and the renewed commitment to finding an international agreement," he said.
"But in the meantime, there's evidence that the Earth's response to climate change might be going faster than people have predicted. The dramatic loss of ice in the Arctic, for example, poses a serious concern for the northern hemisphere climate."
Professor Rapley said the letter to Nature, one of the world's most prestigious scientific journals, was intended to get people thinking about the concept of technical fixes rather than just to advocate ocean pipes.
"If you think of how the science community has organised itself," he said, "with the World Climate Research Programme, the International Geosphere-Biosphere Programme, International Polar Year and so on - you've got all this intensive interdisciplinary collaboration figuring out what Earth systems are up to and figuring out how they work, but we don't have a similar network working across the entire piece as to what we can actually do to mitigate and adapt."
He said there was a need for some sort of global collaboration to explore potential climate-fixing technologies.
"Geo-engineering is one of the types of thing that are worth investigating," opined Ken Caldeira, "and yes, the amount of effort going into thinking of innovative solutions is far too little.
"If we can generate 100 ideas, and 97 are bad and we land up with 3 good ones, then the whole thing will have been worthwhile; so I applaud Lovelock and Rapley for thinking along these lines."
He observed that human emissions of greenhouse gases are bringing huge changes to natural ecosystems anyway, so there was nothing morally difficult in principle about deliberately altering the same natural ecosystems to curb climatic change.
But changing patterns of ocean life could potentially have major consequences for marine species. Whales that feed on krill, for example, could find their favourite food displaced by salps.
These would all have to be investigated, James Lovelock acknowledged. But, he said, it is time to start. "There may be all sorts of ecological consequences, but the stakes are terribly high."
National Geographic News 26 Sep 07
Giant Ocean Tubes Proposed as Global Warming Fix
Imagine an ocean full of giant pipes that pump up cold, nutrient-rich water from deep below, encouraging surface algae to bloom and suck carbon dioxide from the atmosphere.
That's the controversial new vision of James Lovelock, the independent British scientist best known for proposing the Gaia hypothesis, and Chris Rapley, a space physicist and director of London's Science Museum. The pair claims that such climate engineering solutions may be the only way to hold global warming at bay given its current progress.
"Global warming appears to be an irreversible process, and if we don't do anything then the world will just heat up to a stable, hot state," Lovelock said. "The stakes are now so high that we have to act."
But other experts are skeptical, pointing out that the scheme could release more carbon than it absorbs while putting fragile marine life in danger.
Lovelock and Rapley say their proposal is the oceanic equivalent of planting trees. But with more than two-thirds of Earth covered in ocean, the plan could be applied on a much grander scale.
The pair's preliminary calculations indicate that an array of between 10,000 and 100,000 pipes would be required, with each pipe around 33 feet (10 meters) wide and 330 feet (100 meters) long. Wave energy would make the pipes bob up and down. One-way valves inside the pipes would then force water to circulate, bringing nutrient-rich water up to the surface.
"This would stimulate algal growth and help to draw down carbon dioxide," Lovelock said.
A further benefit from the increased algal blooms is that they would produce dimethyl sulfide, a chemical that helps sunlight-reflecting clouds to form, the scientists say. The idea is outlined in this week's issue of the journal Nature.
"In principle this idea should work, and it should definitely be examined further," said John Latham, an atmospheric scientist at the University Corporation for Atmospheric Research in Boulder, who is also developing engineering solutions to mitigate climate change.
Preliminary laboratory tests using cylindrical pipes in a tank of water have shown that the concept has potential, at least on a small scale, Lovelock and Rapley point out.
Making the Problem Worse?
But there are a number of issues with such a proposal, other researchers say.
"Pumping deep water to the surface not only pumps nutrients up, but also carbon dioxide," said Penny Chisholm, an environmental engineer at the Massachusetts Institute of Technology in Cambridge.
Initially the deep waters might "exhale" carbon dioxide into atmosphere, adding to the global warming problem. "Only after the outgassing is complete will the surface ocean start to take up carbon dioxide, and it is unclear whether there will actually be a net transfer of carbon dioxide to the deep ocean," said Eric Achterberg, an oceanographer at the University of Southampton in England.
Another concern is that meddling with oceanic water circulation might be damaging to ocean life.
"If done on a large enough scale then problems with oxygen depletion could occur in subsurface waters, which would probably have knock-on effects for ecosystems," said Toby Tyrrell, an ocean ecology expert at the University of Southampton.
Time to Test
Lovelock and Rapley acknowledge that there could be problems but still think that the idea deserves to be tested. The problem of global warming is so serious, they say, that we may have to resort to climate-engineering solutions and accept some of the unwanted consequences.
"Even if we stopped emitting carbon dioxide tomorrow we are still committed to significant temperature rise," Rapley said. "We don't think that scrubbing carbon dioxide out of chimneys and driving energy efficient cars will be sufficient. We need to draw carbon dioxide out of the atmosphere too."
The pair is already working with an anonymous sponsor on building an oceanic prototype. "We can do a small-scale trial and discover any problems, giving us opportunity to back off if need be," Rapley said. If all goes well the scientists envision situating their pipes in areas where they would have a dual purpose, such as the Gulf of Mexico and the Coral Sea off northeast Australia.
Cooler surface waters in such locations could help take the oomph out of Atlantic hurricanes and revitalize coral in the Great Barrier Reef.
The new proposal ties back to Lovelock's best-known work, the Gaia hypothesis. In the 1960s Lovelock formulated the idea that Earth functions like a living organism, with both living and nonliving parts interacting to regulate the planet's environment.
Lovelock and Rapley see today's global warming as a disease of Earth caused by human actions. "Our idea is to stimulate the Earth's immune system," Rapley said, "and help it to cure itself of its current infection."
Plan to Dump Iron in Ocean as Climate Fix Attracts Debate
Kelly Hearn National Geographic 25 Jul 07
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