Now scientists suggest an almost provocatively simple mechanism that might have kept the planet from cooling more severely than it actually did during past glacial climates: Changes in terrestrial vegetation stopped the weathering-driven decline in atmospheric CO2 concentrations which else would have turned Earth into a lifeless freezer.

Weathering is known to be largely controlled by vegetation. So the team, led by Mark Pagani of Yale University, describes in a paper in Nature today a negative feedback whereby limited plant growth during cold conditions slows down the rate of weathering and sedimentation, thus preventing carbon dioxide levels from dropping even further. An editor's summary of the paper is here.

This “bold and provocative” hypothesis provides an “elegant twist” on existing ideas about climate-vegetation interactions, Yves Goddéris and Yannick Donnadieu write in an accompanying News and Views article (subscription required).

But the proposed feedback mechanism raises contentious issues as well. For example, Goddéris and Donnadieu argue that in the tropics the role of vegetation cover in the climate system might not be as significant as proposed.

Quirin Schiermeier

Last week marked the start of a US$5 million project to study the effects of thawing permafrost on ecosystems in the Arctic. Based at the Toolik Field Station in northern Alaska and sponsored by the US National Science Foundation, the project will look at the impact of thermokarsts — the scars and pits left behind as melt water from permanently frozen ground leaks away, and soil and rock collapses in its wake.

The project was inspired by a serendipitous discovery in 2003, says Bowden:

My colleagues and I were flying over the high Arctic in search of research sites. We noted that the Toolik River was brown and muddy, which was odd as it hadn't rained recently. As we went further upstream, we came to a tiny stream that was washing tons of thermokarst sediments into the river. We were astounded how this tiny feature was influencing the river 40 kilometres downstream. The volume that had been displaced was enough to smother the bottom of the entire river. The sediments would release a lot of nutrients normally locked up in permafrost into freshwater cycles. That's got to have a significant impact on the ecosystem.

Read the full interview here.

Anna Barnett

Yesterday afternoon, I had the pleasure of talking with Mario Molina and Sherry Rowland about their work on ozone and their views on science informing policy. We were joined by three young, enthusiastic scientists who are working on various aspects of climate research – solar technology, biofuels and ocean health – and are here at Lindau to interact with the laureates.

Molina and Rowland have a lot to say on the issues of ozone and policy, of course. When they called for a worldwide ban on CFCs, following their discovery that CFCs were destroying the ozone layer, they were, in many respects, pioneers. But though their efforts ultimately led to the phasing out of CFCs, their results – and outspoken views – were initially greeted with caution from the scientific community. I asked them what the young scientists working on climate change can learn from their experience.

Rowland was adamant that young scientists should not be afraid to speak up on the implications of their research. I queried them on how far researchers should go in speaking up. Would they, for example, now call for a worldwide ban on the use of coal, given that coal is such a significant contributor to the problem of climate change? They both responded that a worldwide ban would be appropriate, if carbon capture and storage (CCS) was available. Molina added that we should be cautious of building new power plants that will tie us into using coal for the next 30-50 years, unless we have developed CCS technology.

I met the young researchers – Brandy and Brian from the US, and Faroha from Pakistan – again this morning at 730am to catch up on their experiences at Lindau so far. They all got a lot out the session with Rowland and Molina, who were both thoroughly engaging. Of course, I can tell you all of this on the blog, but it will be much more convincing to see the film once it is on nature.com. Out of an hour of filming, I’m guessing that five minutes, at most, of yesterday’s session will make it into the final cut.

After hearing talks on sustainability and energy from Harry Kroto and Walter Kohn, this afternoon, I recorded some of the narrative links for the film. The face-to-camera pieces are by far the trickiest!

The next piece will be recorded Friday as we make our way by boat to Mainau island – home of Countess Bettina Bernadotte – where a panel on climate change is being convened. I’ll be back with an update from that on Friday.

Olive Heffernan

Two challenges exist in deploying renewable technologies on a large scale, said the panelists. Namely, these are storage and transport of energy. “ We cannot create energy. We can only transform the energy coming to earth from the sun. So it’s just a question of how we can transform and store this energy”, said Gerhard Ertl, who won the 2007 Nobel Prize in Chemistry.

Robert Grubbs of Caltech, the only organic chemist cum-laureate on the panel, said that materials scientists could play a critical role in solving these problems, such as by designing lightweight, large blades for wind turbines.

There is a huge amount of solar energy available and a smaller amount of wind energy available, said theoretical physicist Walter Kohn, who received the 1998 Prize for his contributions to the understandings of the electronic properties of materials. Kohn said that the challenge is turning this vast amount of energy into something usable.

But that something will also have to be safe, suggested Kohn, who expressed particular concern about replacing fossil fuels with nuclear power. “I’m old enough to have witnessed the affect of nuclear bombs, and I’m a young enough that I can still read the newspapers”, he said, referring to the threat of nuclear proliferation in Iran and North Korea. “If this became a major source of replacing fossil fuel, the number of power plants needed would create…a huge probability of leading to a catastrophe”, said Kohn, who worries that “there will a tremendous pressure to go for nuclear” none-the-less.

Laureate Harold Kroto agreed that the pressure to use nuclear energy will be “irresistible” and raised the issue of whether scientists need a new Manhattan project to develop new technologies. Kroto argued that blues skies research will be perhaps more valuable than applied research here, because often the accidental leads to new discoveries.

“Do we need some kind of new chemistry”?, asked Kroto. In developing new technologies “we have a responsibility to society that our discoveries should not be misused”, he added. “This is a worry that many of us have”.

Olive Heffernan

Nature Geoscience’s latest issue highlights the challenges of understanding fluctuating sea level – from 70 million years ago to the future (sea level content free to registered users). A collection of commentaries and research papers look at how sea level has changed in the past and try to project its future evolution. In addition, the issue provides insights into some of the societal impacts of sea level change, and how some countries are planning for the future.

Most of the delegates are students who have been selected by a panel to participate in the event, where they will have a unique opportunity to interact with some of the greatest scientific minds on the planet.

I’m here with a team from Nature, and a film crew, who are making a series of short films on this year’s meeting, which is dedicated to chemistry. A sizeable proportion of the programme is on climate change and sustainability (which is just as well given that I left chemistry behind as a second year undergraduate to pursue earth sciences), so one of our films will focus on those issues, specifically on the role of scientists in informing policy.

After arriving on Saturday we had the tough job of selecting the young researchers who will participate in the films this year. For the film on climate change, that meant choosing just 3 finalists out of the several dozen applicants. It slightly felt like being an 'X factor' judge, but luckily we were all in agreement on the final call.

As well as discussing science itself, many of the young researchers see the Lindau meeting as an opportunity to learn about what it takes to be a great scientist and to discuss the broader role of scientists in society.

In the opening ceremony on Sunday afternoon, Kapil Sibal, Indian Minister for Human Resource Development, who has just been admitted to the Honorary Senate of the Lindau Foundation, said that scientists must stay above politics and not be constrained by history. Science and technology are “value neutral”, but “can used for good or bad”, said Sibal. He urged the next generation of scientists to think carefully about the applications of their work and to whether it can be used for the good of society.

Anna Barnett

The idea for the Lindau meeting was originally conceived - together with two physicians - by Count Lennart Bernadotte of Wisborg, a member of the Swedish royal family, who had a lifelong interest in science. Wisborg saw the meetings as a “window to the world” for the international scientific elite of present and future generations.

This year’s event, which runs from this Sunday until Friday July 3rd, is dedicated to chemistry, and will be attended by 23 Nobel Laureates and 580 young researchers from 67 countries.

I’ll be traveling there tomorrow with colleagues and a film crew to meet with some of the best world’s best atmospheric chemists. Attending Lindau this year are Mario Molina, Sherwood Rowland and Paul Crutzen, who jointly received the Nobel Prize in 1995 for their work on stratospheric ozone depletion, which led to the discovery of the hole in the ozone layer.

Also on this year’s programme is a panel discussion with Rajendra Pachauri and Thomas Stocker of the Intergovernmental Panel on Climate Change, the UN climate body that shared the 2007 Nobel Peace Prize with Al Gore.

While at Lindau, we’ll be making a short film about the role of climate scientists in speaking on and advising on policy. When Molina and Rowland first published their results on ozone depletion in a 1974 Nature paper, they were conventionally understated in communicating the wider implications. But when the research failed to grab much attention, they went public on their concerns and called for a worldwide ban on CFCs. Their call was successful and ultimately led to the formation of the Montreal Protocol, the international treaty designed to phase out the use of CFCs.

There is perhaps much to be learned from their experience today. Climate scientists are increasingly being asked to communicate the implications of their research to policy makers, and indeed to make their research more policy relevant. Clearly, the solution to climate change will not nearly be as simple as the phasing out of CFCs. But while some climate scientists (and perhaps one in particular) have not held back in speaking their minds openly on policy, many others have. Perhaps this is out of concern that by becoming advocates they would damage their credibility as independent scientists. But with so much at stake, is that position justifiable? I’ll be exploring this question, among others, next week in Lindau.

You can follow the Lindau meeting here on Climate Feedback, where I'll be blogging daily.

Olive Heffernan

The loss of £4.3 million (US$7.0 million) in funding from the MoD will affect the Met Office Hadley Centre for Climate Change in Exeter, the world-class climate modelling institute whose researchers made key contributions to the last assessment report of the Intergovernmental Panel on Climate Change (IPCC) in 2007.

"This news comes as a shock," says climate scientist Martin Parry, formerly at the Met Office and now at the Grantham Institute for Climate Change at Imperial College London. "The UK's core modelling work on climate change has been funded from this source, up to now."

The Met Office is now in negotiations with other goverment departments in an effort to recoup some of the lost funding.

Read the full story over on Nature News.

Olive Heffernan

Image: UK Met Office

Hansen, along with actress Daryl Hannah and other protesters, apparently planned to deliberately trespass on the property of mining company Massey Energy in the appropriately named Coal River Valley, West Virginia (press release).

However, a counter protest by miners and coal industry supporters forced them to change their plans. Instead, according to the Charleston Gazette, they sat down in the road outside Massey Energy's Goals Coal preparation plant in Raleigh County and were arrested for obstructing the police and impeding traffic.

Some reports say Hansen and other actually did trespass. Another account alleges a coal supporter assaulted members of the Hansen protest group.

Hansen, of course, has a long history of opposing coal power. He even appeared with Hannah before at a climate change protest, where Nature reporter Jeff Tollefson noted “Hansen says he is willing to get arrested”.

Willing and able, it seems.

More
Photos of the protest and arrests – RAN
A Plea To President Obama: End Mountaintop Coal Mining - Hansen on the Enivronment 360 blog

Cross-posted by Daniel Cressey on The Great Beyond

Image: Hansen at a previous protest / Jeff Tollefson

We’ll be moving to a new blogging platform soon, and will have more updates on the blog then. In the meantime, if you have any suggestions for additions to our blogroll, please list them in the comments section or email them to us at climatefeedback@nature.com

One book that’s been receiving considerable attention – and praise – is Anthony Giddens’s aptly named The Politics of Climate Change.

A sociologist at the London School of Economics, Giddens is best known as mastermind of New Labour’s 'third-way' politics of the 1990s, in which he tried to move politics beyond the traditional debates of the left and right. In his latest book, he applies the same ‘third way’ rationale to the problem of climate change. Roger Pielke Jr. has reviewed Giddens’s new book for us over on Nature Reports Climate Change. In brief, his assessment is that as a philosophical treatise, The Politics of Climate Change is excellent and in places even brilliant, but that Giddens fails to translate his brilliant philosophies into concrete policy options.

You can read the full review here.

Olive Heffernan

The projections, released yesterday in London, offer the most detailed picture yet of how the UK - piece by piece, in sections just 25 km sq - will be affected by various climate impacts.

Their main message is that without substantial efforts to cut global greenhouse gas emissions, Britons could be in for a hard time by the 2080s. While the risk of flooding will worsen in the North West, the South East will face an anticipated 22% decline in summer rainfall. If emissions continue to rise, London will likely experience a 2-6°C degree rise in temperature and sea-level rise of 36cm.

The UK government hopes the information will enable citizens and local authorities adapt to the changes that lie ahead, but some fear the projections provide misleading information.

That’s because the method used to produce these highly detailed projections of the future is new – and hasn’t yet been through peer-review. Bob Watson, chief scientist with the UK Department of the Environment Food and Rural Affairs (DEFRA) is confident it’s just a matter of time before the methodology is used on a broader scale. He expects it “will be taken up by other regions and highlighted by the IPCC in their next report”.

But while the projections were originally slated for release last November, an independent committee was convened at the eleventh hour to check out the methodology.

Oxford climatologist Myles Allen was on the committee, and he’s concerned that the results stretch the science beyond its current capabilities. His main worry is that as recently as 2007, the Intergovernmental Panel on Climate Change didn’t think that climate variables could be reliably resolved at spatial scales beyond a couple of 1000kms. And no research published since has challenged that view.

He spoke to me about this for Nature News, where I’ve covered the story in detail. He also spoke of his concerns on yesterday’s Newsnight, which is definitely worth a look.

The evidence comes from the De Soto Caverns in Alabama. This cave has already offered up rich history of a non-palaeoclimatological kind: it holds a Native American burial ground and an abandoned moonshine distillery from the 1930s, when good-timing Alabamans used to shoot down the stalactites.

"This site is the Pompeii of ancient Mesapotamia," says Weiss. "They walked away."

Weiss reviewed evidence that a rapid change in storm tracks in the North Atlantic - yet to be satisfactorily explained - dried out the Tigris and Euphrates valley 4,200 years ago. And that valley wasn't alone. Around the same time, deflection of the Indian Monsoon hit the Nile with a drought, and Egypt's Old Kingdom went down. The extreme events are also mirrored in North America from New Jersey to the Yukon. In a separate talk today, glaciologist Lonnie Thompson showed a new ice core data* from Huascarán in Peru, the highest tropical mountain, with a huge spike in dust deposition around this time. The dust probably blew off an aridifying West Africa, Thompson says.