Climate Feedback

Despite decades of research, relationships between clouds, aerosols and precipitation are poorly understood, concludes a review article in Nature today.

Before a cloud can produce rain or snow, rain drops or ice particles must form. Atmospheric aerosols, tiny particles of mineral or organic origin, serve as the nuclei for condensation.

But the precise effects of aerosols on cloud formation and radiative forcing remain controversial. In their review article, Bjorn Stevens and Graham Feingold propose that the uncertainties reflect a failure to take into account processes that act to buffer the response of clouds and precipitation to aerosol changes. Worse, existing tools and methodologies for untangling these processes are inadequate, they say.

"If we wish to make significant strides in understanding the interplay among the aerosol, clouds and precipitation, we consider it imperative to launch significant new international initiatives, with comprehensive, coordinated and enduring measurements, targeting specific regimes and coupled to state-of-the-art modelling," the duo concludes.

Among other things, they say, what's lacking is an array of ground-based remote sensors capable of vertically and temporally resolving the aerosols, clouds, precipitation and the meteorological state.

Quirin Schiermeier

Image: Flickr user laffy4k, Creative Common license

Posted by Anna Barnett on September 30, 2009
Categories: Atmospheric Science, Quirin Schiermeier | Permalink | Comments (1) | TrackBacks (0)

If we are trying to keep global warming to 2 degrees Celsius or less but 4 degrees is possible even within some of our lifetimes, which world do we prepare for? Talks at today's session on adaptation took on the problem of the multiple futures that decision-makers have to face. Mark Stafford-Smith of CSIRO in Australia talked specifically about long-term decisions - such as planting and managing forests - where the best option depends on which way the climate goes later this century. If you expect strong mitigation that holds down warming, then you try to preserve today's forests and nurse them through, protecting them from fire and other threats. If a moderately high temperature is in store, forest composition will have to change and you can plant new species to facilitate that. With runaway climate change the best option could be opening up the forests to invading weeds and rapid, radical transformation.

This is no hypothetical choice. During February's raging wildfires in southeastern Australia, it appears that even the seed stores in the forest floor were destroyed in some burnt areas. Stafford-Smith recommends that conservation managers trying to bring these areas back to life should divide their efforts to follow all three approaches above. Such a hedging strategy may mean two-thirds of forest plans need to be abandoned and altered as the future unfolds, but it's better then putting all the trees in one basket.

Rob Swart of Wageningen University, The Netherlands, looked at hedging on a much larger scale - the plan Bs we could prepare in case of a true planetary emergency. From geoengineering schemes that risk severe side effects to extreme emissions reductions that would affect the climate only slowly and probably require tight government control, none of the options are attractive. But Swart thinks there should be an international process - separate and parallel to current UN climate policy - for countries to work out ahead of time how they would cooperate on such schemes. If left to a moment of panic, they're unlikely to be carried out thoughtfully and equitably.

Anna Barnett

Posted by Anna Barnett on September 30, 2009
Categories: 4 Degrees and Beyond, Adaptation, Anna Barnett, Climate Policy | Permalink | Comments (0) | TrackBacks (0)

Immersing yourself in the impacts of extreme climate change can give rise to a certain amount of gallows humor. Conversation among my dinner companions last night turned to whether this week's 4 Degrees and Beyond conference or March's Copenhagen Climate Congress provided "more apocalypse for your conference fee". The far more serious question, of course, is how much upheaval and human suffering would come with the substantial warming that delegates here are contemplating. Some interesting talks today looked at the facets of sea level rise and population displacement.

Stephan Rahmstorf of the Potsdam Institute for Climate Impacts Research had an intriguing update on a 2007 Science paper in which he'd come up with a new method for projecting sea level rise. Rahmstorf throws out any attempt to use complex climate models on this controversial problem and instead starts from scratch, with observed relationships between temperature rises and sea level rises. Now, working with Martin Vermeer of the University of Technology in Helsinki, he's upgraded the extremely simple equation he used in 2007 to an only slightly less simple equation - one that takes account of the rate of warming and the amount of water that humans sequester in reservoirs. They use this to reconstruct a remarkably faithful record the last millennium's sea levels.

Turning it to IPCC temperature projections, the team finds that sea level rise by 2100 could range, depending on the emissions scenario, from 0.75 to 1.9 metres, and a 4-degree world would likely see 0.98 to 1.3 metres of rise this century. A caveat: the recent sea-rise data that inspired and calibrated this equation and the past data that it explains don't include the full effects of melting ice sheets that could lie ahead. That means 0.75 to 1.9 metres may be a conservative estimate.

But if we're concerned with how creeping seas affect coastal populations, the amount of rise is not the only matter to settle. This was a key argument made by Francois Gemennes of the Institute for Sustainable Development and International Relations in Paris. Gemennes' talk was based on a study of environmentally induced migration that I covered earlier this year. When it comes to climate refugees, he says, the numbers that are often tossed around - such as 200 million new migrants by 2050 - are based on the assumption that greater climate impacts will push more people around. What they aren't based on is empirical data about how populations respond to environmental change. But according to the recent EACH-FOR project - the first global-scale survey of environmental migrants - the size of impacts isn't the crucial variable at all: migration largely depends on policies making it possible for people to react to impacts by migrating. In particular, Gemennes argues, the poorest and most vulnerable will not be able to migrate unless they are given resources and exit routes - if we don't encourage migration as an adaptation strategy, they'll be trapped in the frying pan (or flooding delta).

The next event of the conference is a panel discussion on "4 degrees of climate change: alarmist or realist?", which I'll be tracking over on Twitter. Follow @annabarnett.

Anna Barnett

Posted by Anna Barnett on September 29, 2009
Categories: 4 Degrees and Beyond, Adaptation, Anna Barnett, Ocean science, Society | Permalink | Comments (0) | TrackBacks (0)

Unless major breakthroughs in policy, industry and individual behavior turn around our emissions trajectory pronto, this century could well see average global temperatures 4 degrees Celsius or more above their pre-industrial baseline. That's the starting point for the 4 Degrees and Beyond conference in Oxford this week. Here, 130 scientists and policy experts are taking a detailed look at a world warmed by twice the amount that's usually considered dangerous.

Putting weight behind the 4-degree premise was new modelling research presented this morning by Richard Betts of the UK Hadley Centre (press release, Guardian). Betts's team used a complex, coupled ocean-atmosphere model to simulate the IPCC's extreme-emissions A1FI scenario (the FI stands for fossil fuel intensive) - an emissions trajectory that's previously been run only on simpler models. It's time to take this scenario seriously, argues Betts, given that our emissions are running at the upper end of what the IPCC projected a decade ago.

They also tried out weakening climate sinks on land and sea - feedbacks that are increasingly apparent in recent research, Betts says. Depending on the strength of the feedbacks, 4 degrees of average warming could be reached well before 2100 - as early as 2060 in a worst case scenario, and in the 2070s according to the team's best guess. Regional warming would be far greater, they found - 7 degrees in many areas, up to 10 in western and southern Africa, and 10 or more in the Arctic.

Sessions afterwards started sketching out consequences in detail. Philip Thornton of the University of Edinburgh looked at agriculture in Africa, where projected impacts are predictably devastating, with yields falling over 50% for certain crops and crop failure years growing more frequent in many regions. Adaptations for this amount of change are a big question mark. Intensive agriculture in highlands - among the few spots that will benefit - may be one possibility for preserving the food supply.

Meanwhile in Finland - where you might expect balmier weather to be a boon - intense climate change may also prove a curse to farmers, reports Reimund Rotter of MTT Agrifood Research Finland. The picture there is complicated - the possible responses depend on many variables. A new type of barley that might compensate for losses to rising temperature or drought would only work in certain soil types, for example. But it's clear that the North as well as the South will have its problems with the radically different 4-degree world.

Anna Barnett

Posted by Anna Barnett on September 28, 2009
Categories: 4 Degrees and Beyond, Adaptation, Anna Barnett, Climate Science, Climate prediction, Society | Permalink | Comments (0) | TrackBacks (0)

"There are two El Ninos."
The University of Miami's Ben Kirtman, co-author of a study published in this week's Nature, on a newcomer El Nino pattern that will get a boost from climate change.

Emissions of CO2 Set for Best Drop in 40 Years
The International Energy Agency expects a 2.6% decrease in global emissions in 2009, largely thanks to the recession.

"We call on all member states to hold back from attempting to make use of a loophole that simply has to be closed for the carbon market, and European climate policy, to continue on a sound footing."
An EU court rules that Poland and Estonia can choose to dole out plentiful carbon emissions allowances; the International Emissions Trading Association implores other countries not to follow suit.

"There are a host of human-induced factors that already cause deltas to sink much more rapidly than could be explained by sea level alone."
The Colorado, Nile, Pearl, Rhone and Yangtze deltas are all increasingly prone to flooding because of dams and groundwater extraction, multiplying the risk of climate impacts, according to a new study in Nature Geoscience.

Posted by Olive Heffernan on September 25, 2009
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A newly launched series of Google Earth tours will map out the projected impacts of climate change worldwide and look at mitigation and adaptation options. Here's a brief intro, narrated in the light Tennessee drawl of Al Gore:

The full length intro is here, with more tours to come. Google is also inviting netizens to talk back about climate change on a new YouTube channel.

While you're playing with climate science layers on Google Earth, you may want to check out our interactive map of polar ice coring sites where researchers have extracted hundreds of millennia of climatic history.

Anna Barnett

Posted by Anna Barnett on September 25, 2009
Categories: Anna Barnett, Communicating Climate Change, In the News | Permalink | Comments (0) | TrackBacks (0)

After a banner week of international summits, a great leap forward on climate policy has yet to materialize, and some players are expressing a growing frustration.

US President Obama and Chinese President Hu Jintao both gave big speeches at a UN meeting in New York on Tuesday, but they didn’t make any bold leadership moves.

Jeff Tollefson has a briefing in Nature News on what went down:

Everybody is looking for signs of progress from the two biggest emitters, who together account [for] roughly 40% of emissions, but neither president offered the kind of commitments needed to re-energize the talks. Obama was in the unenviable position of needing to make bold promises before the US Congress has weighed in on the issue. Nonetheless, he declined to acknowledge, let alone address head on, the challenges he is facing on the domestic front.

For his part, Hu largely underscored existing policies, promising to expand forests, produce 15% of the country's power using renewable energy and decrease energy intensity per unit of gross domestic product by a "notable margin" between now and 2020. All of these would substantially reduce Chinese emissions compared with baseline forecasts, and China is beginning to win some praise for its energy policies. Nonetheless, cumulative emissions are expected to continue rising, and Hu made no reference to any specific emissions targets or a date by which the country might try to stabilize its emissions.

As Jeff explains, almost everyone agrees with these statements, but they are old hat. And the clock is ticking. Says campaigner Steve Howard, founder of The Climate Group, in a New York Times story on the summit: “It was really great to have the vision, but with just 70 days left to Copenhagen, it is time to put some substance on the table. The two most important countries on this issue are being guarded in their positions.”

Obama’s speech did impress one observer, at least. Fidel Castro praised him as “brave” for acknowledging that the US has been slow to act on climate change.

Following closely was the G20 summit in Pittsburgh, which started yesterday evening and continues today. With financial policy expected to take up much of the agenda, hopes aren’t high for a climate breakthrough there either.

Continue reading "Climate summits underwhelming, say leaders" »

Posted by Anna Barnett on September 25, 2009
Categories: Anna Barnett, Climate Policy, In the News | Permalink | Comments (0) | TrackBacks (0)

Considered by some a silver bullet and by others a hopeless dream, the idea that we can simply capture our carbon dioxide emissions and store them safely away is nothing if not compelling. After all, it lends an air of practicality to the notion that human ingenuity can somehow continue the unabated use of fossil fuels over the coming decades without dangerously warming the climate.

This week’s Science (subscription) looks at how close we are to being able to capture carbon dioxide, both from the point of emission at coal- or gas-burning power plants, and directly from air. A series of news, opinion and review articles shows that while many obstacles need to be overcome before carbon capture and storage (CCS) is implemented effectively, there are also abundant reasons to hope that it will happen.

But the scale of the challenge is palpable. In a review, Stuart Hazeldine of the University of Edinburgh, UK, says that the construction of many tens to hundreds of large CCS plants worldwide would be needed to reduce future worldwide emissions from energy by 20%. And in order for the technology to make a substantial contribution to climate mitigation, a viable CCS industry needs to be in place between 2020 and 2030. Construction would have to start now if plants fitted with CCS technology are to be operational by 2014, giving enough time to demonstrate commercial credibility by 2020.

Last year, G8 leaders called for upwards of 20 demonstration CCS projects around the globe. A recent report from
the U.S. National Research Council reiterated this statement, calling for a suite of 15 to 20 power plants with CCS to be built before 2020. Today, a few such projects are in development, each of which is shown on a map accompanying the Science news feature. Most of these projects will take CO2 from natural gas reservoirs and bury it or pump into oil reservoirs to force more oil to the surface, thus making the whole process commercially viable. One such project is China’s first large-scale CCS effort, which is due to launch at a site on the plains of Inner Mongolia in the coming weeks.

But many more such plants are needed, and despite a recent boost in available money for CCS, Hazeldine notes that there is still a “lamentable lack of financial commitment to real construction”. His take home message? Technology isn’t the bottleneck in getting CCS off the ground. On the 10 year timescale, it’s legal permission, business development, and public opinion that could prevent CCS from being up and running by 2020.

Also featured in the Science special issue is a perspective by David Keith on the potential for direct capture of CO2 emissions from air, which Nicola Jones covered in a news feature for Nature (subscription) back in May. The special also has a number of perspectives on the technological aspects of CCS, from capturing CO2 to storing it onshore in geological formations or offshore in deep-sea sediments.

Olive Heffernan

Image credit: Carbon storage at Sleipner field, North Sea. Alligator film /BUG / StatoilHydro

Posted by Olive Heffernan on September 24, 2009
Categories: Funding, Mitigation, Olive Heffernan, Technology | Permalink | Comments (0) | TrackBacks (0)

Many glaciers in Greenland and Antarctica are speeding up their slide into the sea. But this type of ice loss - known as dynamic thinning - is so ill-understood and difficult to predict that the IPCC, in their 2007 assessment report, threw up their hands and refused to guess how much it would contribute to future sea level rise.

Meanwhile, however, scientists have been working with a new tool for studying glacier flow: NASA’s ICESat spacecraft. This satellite uses a laser to measure the changing height of the glaciers with spatial resolution an order of magnitude better than its predecessors.

The results from 2002-2007 are just in, published as a Nature paper (subscription) online this week:

Dynamic thinning of Greenland and Antarctic ice-sheet ocean margins is more sensitive, pervasive, enduring and important than previously realized.

Continue reading "ICESat's eye on runaway glaciers" »

Posted by Anna Barnett on September 24, 2009
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Despite the apparent stress that humanity is causing to the Earth system, defining sustainable limits for our own existence has proved to be something of an intractable problem. But what if we could define global sustainability numerically?

In this issue of Nature, a group of renowned earth system and environmental scientists led by Johan Rockström of the Stockholm Resilience Centre make a first attempt at estimating boundaries for the biophysical processes that determine the Earth’s capacity for self-regulation.

Using existing data, Rockström and colleagues put ‘acceptable’ upper limits on seven environmental parameters: climate change, ocean acidification, stratospheric ozone depletion, freshwater use, biodiversity loss, the global cycles of nitrogen and phosphorus, and land-use change. Crossing even one of these boundaries, they say, would risk triggering abrupt or irreversible environmental changes. And if one boundary is transgressed, then others are at serious risk of being breached.

For some parameters, such as nitrogen loading and atmospheric CO2 concentrations, we may have already stepped out of our safety zone and need to back-pedal quickly. For others, such as ocean acidification, we may still have enough time to avoid catastrophic change if we act wisely.

But do we understand the Earth system well enough to know the real limits to environmental degradation? And if we can define them, even roughly, would doing so would ultimately help or hinder efforts to protect the planet? We posed these questions to seven leading experts, who were invited to respond to the ‘planetary boundaries’ proposal. Each author brings specific expertise to evaluating one aspect of the proposed framework. Their responses can be freely accessed at Nature Reports Climate Change. We’ve weighed in with our own thoughts in an editorial in Nature, and with a podcast. All of Nature’s coverage, plus a full length version of the paper by Rockström and colleagues, can be accessed here.

The commentaries are available individually at the following links:

William H. Schlesinger, President of the Cary Institute of Ecosystem Studies in Millbrook, New York comments on the boundary for global nitrogen and phosphorus cycles (html|pdf).

Steve Bass, senior fellow at the International Institute for Environment and Development, UK comments on the boundary for land-use change (html|pdf).

Myles Allen, physicist and climatologist at the University of Oxford, UK comments on the boundary for climate change (html|pdf).

Mario J. Molina, director of the Mario Molina Center for Strategic Studies in Energy and the Environment in Mexico City comments on the boundary for stratospheric ozone depletion (html|pdf).

David Molden, deputy director general for research at the International Water Management Institute in Sri Lanka comments on the boundary for freshwater availability (html|pdf).

Peter Brewer, ocean chemist and Senior Scientist at the Monterey Bay Aquarium Research Institute in Moss Landing, California comments on the boundary for ocean acidification (html|pdf).

Cristián Samper, Director of the Smithsonian National Museum of Natural History in Washington DC comments on the boundary for biodiversity loss (html|pdf).

For the most part, our respondents agree that the ‘planetary boundaries’ framework is a useful and worthwhile endeavour. But they also issue words of caution in choosing upper limits on environmental degradation. Some such as ocean chemist Peter Brewer question whether we know enough to choose the right parameters; on ocean acidification, for example, does an upper bound on aragonite saturation fully represent the potential detriment of loading the ocean with CO2?

Continue reading "Planetary boundaries " »

Posted by Olive Heffernan on September 23, 2009
Categories: Features, Olive Heffernan | Permalink | Comments (40) | TrackBacks (0)

One of this year's Heinz awards - a $100,000 prize for achievement in environmental science and leadership - is going to Chris Field, the Stanford ecologist and leading carbon-cycle expert who became co-chair of IPCC Working Group 2 in 2008.

"Chris Field receives a Heinz Award for his contributions towards understanding the impacts of climate change on Earth’s ecosystems, as well as for his national and international leadership in bringing science to the policy process," the Heinz foundation said. "He has played a critical role in the emergence of global ecology as a unique discipline, applying it to diverse questions concerning the scientific foundations for a sustainable future."

Congratulations to Chris!

Anna Barnett

Posted by Anna Barnett on September 18, 2009
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This week in Nature you can read the first (subscription) of four articles unpicking the business of biofuels. First up is jatropha – the shrub that promised to give drought-ridden countries boundless oil supplies. The reality has turned out to be somewhat different. After a period of hype and over enthusiasm, investments have dried up, somewhat like the promise of oil from arid land.

Jatropha definitely still has a future, but the plant genetics really need to be better developed and a number of companies are now doing this, including London-based D1oils – a company which hit trouble earlier this year when a deal with oil giant BP fell through.

We also catch up with Pushpito Ghosh, director of India’s Central Salt and Marine Chemicals Research Institute. Nature first encountered Ghosh in 2007 when jatropha was still promising the Earth. His project seems to have benefited from a realistic approach from the start. Here we see a photo taken just last week at a CSMCRI plantation in Mahuda, Orissa. Each plant in this kind of harvest gives 1.75–2.25 kg of seeds, which have the oil extracted and the waste turned into briquettes.

The series continues next week with a look at bioalgae as a potential fuel source. After that comes cellulosic bioethanol, followed by the potential for a ‘green gasoline’ to be used as a simple drop-in-fuel replacement.

Katharine Sanderson

Image: CSMCRI

Posted by Anna Barnett on September 17, 2009
Categories: Energy, In the News, Katharine Sanderson | Permalink | Comments (1) | TrackBacks (0)

The Greenland ice sheet melted much more rapidly as a result of warmer temperatures in the recent past than previously estimated, a team of international scientists has revealed. They warn that future warming could have more dramatic effects on the ice than researchers have assumed. The research is from this week's Nature and there's a news story about it over at Nature News.

This study is the latest in a series to use data from ice cores to fathom out what was going on in Greenland's climatic past. Between 9,000 and 6,000 years ago, Earth went through an unusually warm period. But puzzlingly, unlike data from many other spots in the Northern Hemisphere, measurements of isotopes in ice cores drilled from the Greenland ice sheet haven't reflected that temperature change. So models of the ice sheet's behaviour based on these data have suggested that the height of the ice sheet has remained quite stable during the past 12,000 years.

Now, new data from ice cores drilled in six different places on and around the ice sheet reveal that this unusually warm period affected the GIS too, and that in response to these temperatures — which were 2–3 °C hotter than our current temperature — it lost 150 metres in height at its centre and shrank by 200 kilometres at the edges.

Continue reading "Climate change warning from Greenland" »

Posted by Kerri Smith on September 16, 2009
Categories: Palaeoclimate | Permalink | Comments (3) | TrackBacks (0)

The United Nation’s upcoming climate summit in Copenhagen threatens to get caught in a trap between high expectations and the immense complexity of the task at hand, warns the author of an opinion piece in Nature today [subscription]. Since diplomats cannot possibly produce a useful treaty for the December meeting in the remaining twelve weeks, negotiations should focus on a small number of realistic goals, and leave the rest for later, says David Victor, an expert on international relations at the University of California in San Diego.

A rushed and over-ambitious agreement in Copenhagen, even if it had the superficial appearance of success, could in fact prove a “legal zombie” – neither delivering nor dying – and might be counterproductive for long-term climate protection efforts, argues Victor.

He suggests that negotiators in Copenhagen focus instead on few topics, such as reiterating and extending existing emission targets by developed countries and continuing the Kyoto Protocol’s Clean Development Mechanism, whose expiration would shatter the very credibility of international climate diplomacy. A ‘standby’ agreement, shallow though it might appear, could within two years be developed into a fair and efficient global climate strategy.

The post-Copenhagen process, says Victor, would best be led by the small number of rich nations that account for the bulk of global emissions. Given the endlessly cumbersome UN diplomacy that resulted in the meagre 1997 Kyoto Protocol and that weighs heavily on pre-Copenhagen negotiations, “smaller, more flexible approaches offer the only realistic expectations for making progress in 2010 and beyond,” he says.

Global warming, says Victor, is ultimately a problem of economic cooperation, and must be dealt with using the tools and negotiation strategies that have proved most successful in global trade agreements. In trade issues small forums and even unilateral action have indeed shown to be more efficient than global talks.

But is a last-minute ‘plan B’ for Copenhagen simply a polite paraphrase of the climate summit’s foreseeable failure – and an apology in advance?

No, says Victor. A well-managed disaster in Copenhagen is ultimately more likely to pave the way for effective climate protection than a stapled-together deal.

Quirin Schiermeier

Image: Getty

What do you think? Must climate diplomats change their strategy? Join the discussion here on Climate Feedback.

Posted by Olive Heffernan on September 15, 2009
Categories: Climate Policy, Conferences and Meetings, Opinion, Quirin Schiermeier, UN Conference on Climate Change, Copenhagen | Permalink | Comments (5) | TrackBacks (0)

Over on Nature News, Declan Butler has a detailed briefing on the new carbon tax unveiled in France last week:

France is set to become the first major European economy to implement a carbon tax — a levy on activities that emit substantial amounts of carbon dioxide.

Nicolas Sarkozy, the French president, announced on 10 September that the tax would come into effect at the start of 2010. The tax draws largely on recommendations made on 28 July by an expert panel commissioned by the government, and chaired by the former Socialist prime minister, Michel Rocard.

Nature discussed the tax with Jean Jouzel, a member of the Rocard panel, director of the Pierre-Simon Laplace Institute near Versailles, and also the French representative on the executive of the International Panel on Climate Change.

The French carbon tax will be levied at a rate of €17 (US$25) per tonne of CO2 — the current market price. Is that enough to change people's carbon-emitting habits?

What's most important is that a carbon tax of some sort is going to be introduced. Starting at €32 per tonne, as our report recommended, would have been more courageous. The economists on the panel considered that €40 was the minimum for the carbon tax to be effective in changing consumer behaviour, so €32 was itself already a compromise. It's true that the plan is to phase in higher carbon prices over time, but Sarkozy failed to give further details. In the longer term, by around 2020, we need to reach a price of €100–€200 per tonne.

Read the full interview here.

Anna Barnett

Posted by Anna Barnett on September 14, 2009
Categories: Anna Barnett, Climate Policy, In the News | Permalink | Comments (1) | TrackBacks (0)

A new study in Geophysical Research Letters [subscription] adds to the evidence that glaciers in high mountain regions are under threat from climate change.

The research, by Ray Bradley at the University of Massachusetts in Amherst and colleagues, looks at changes in the altitude at which temperature reaches 0 degrees Celsius – known as the freezing level height – in the tropical Andes.

They find that, over the past three decades, freezing level height has increased over most of the region, which is a good indicator that high elevation glaciers are losing mass due to surface melting. Their finding is consistent with observed changes in surface temperature and upper air data in the region, which has experienced a 0.1 degree Celsius increase in temperature per decade over the past half century.

Strikingly, they find that the summit of the Quelccaya ice cap in Peru – the largest body of ice in the Tropics – frequently experiences daily maximum temperatures above freezing between October and May. At the ice cap margin at 5200m, temperatures rise well above freezing for much of the year.

Bradley and co-authors say this phenomenon is likely to be affecting other high elevation glaciers in Ecuador, Peru and Bolivia, with potentially serious implications for the region’s water supply.

Olive Heffernan

Posted by Olive Heffernan on September 10, 2009
Categories: Cryosphere, Olive Heffernan | Permalink | Comments (0) | TrackBacks (0)

Global warming doesn’t just change the weather, it also affects the ozone layer. According to a detailed new modelling study, by 2095 the springtime UV index (UVI) could go up by as much as 20% on the southernmost section of the planet, as altered atmospheric circulation pushes more stratospheric ozone into the Northern Hemisphere. That’s nearly half the UVI increase caused by ozone-eating pollutants in the late twentieth century - but coming from climate change alone.

In a study published in Nature Geoscience this week (subscription), Michaela Hegglin and Theodore Sheperd at the University of Toronto used the Canadian Middle Atomosphere Model, which fully resolves stratospheric circulation, to project ozone changes under the IPCC’s medium-emissions A1B scenario. As climate change unfolded, the model showed increased atmospheric upwelling in the tropics, and what went up in the tropical stratosphere came down disproportionately on Earth’s northern half. As a result, even though the damage done last century by chlorofluorocarbons and other nasties is expected to heal in the next several decades, the ozone layer over the Southern Hemisphere will remain thinner than its pristine state circa 1965.

Continue reading "Sunburnt Southern Hemisphere in 2095" »

Posted by Anna Barnett on September 09, 2009
Categories: Anna Barnett, Atmospheric Science | Permalink | Comments (2) | TrackBacks (0)

Oxford economist Dieter Helm co-edits an upcoming book, The Economics and Politics of Climate Change, that he says takes "a colder and harder look at the challenge". In a Q&A on Nature Reports Climate Change this week, Helm gives his take on a long-term strategy for reducing emissions. Here's an excerpt:

Where, in your view, has policy gone wrong?

Let's remember what lies behind Copenhagen. The Kyoto Protocol measures countries' production of carbon, not consumption. It's no accident the Europeans like Kyoto. It's a set of measures which, as they de-industrialize and production moves to countries like China, makes them look good. But the carbon consumption record of Europe, once you take those imports back, is pretty awful. That's why Kyoto looks like a success, and yet it hasn't caused even a blip in the emissions path.

Do we also need to re-think climate economics?

What we have learnt is that politicians tend to choose the most expensive options first. Faced with climate change, what's our solution? In Europe, it's to devote most of our energies to a rapid build-out of wind power. This is the sort of thing that makes nuclear power look cheap. Climate change is about the massive increase of coal burning internationally, especially the growth of China and India fuelled by coal-based energy — and America too, where the Obama plans are also small relative to the problem.

What exactly will windmills across Europe do to address that overwhelmingly dominant effect? Of course they'll play some role, but it'll probably take a couple of weeks for China to add sufficient new coal power stations to cancel out any renewables effort in Britain. It's time to grow up. It's time to realize that coal is where the core of the problem lies, and to think cleverly about solutions towards that.

Anna Barnett

Posted by Anna Barnett on September 07, 2009
Categories: Anna Barnett, Climate Policy, Economics, In the News, Mitigation, Politics | Permalink | Comments (3) | TrackBacks (0)

Heads of state agreed yesterday in Geneva to establish a global framework to deliver climate services to society. “We agreed on the need for climate services across all nations”, says Martin Visbeck, chair of the committee of scientific experts to the World Climate Conference.

The global framework will oversee the supply of demand-driven climate data to end-users such as farmers to water-resource managers, with the ultimate aim of aiding adaptation to climate change. Climate services would particularly help developing nations, for example, many of which lack access to the weather and climate observations needed to plan their global-warming adaptation strategies.

But the implementation of such services will face several political and scientific hurdles. Over the next four months, an independent task force set up by World Meteorological Organization, which convened the conference, will work out how to make this vision a reality. An arduous 12-month consultation process with signatory nations will then follow.

I’ve reported this for Nature News in full here. The news story covers the scientific challenges ahead in moving from climate ‘projections’ to decadal scale ‘predictions’, and also looks at the issue of data sharing, which will be require some careful negotiating over the coming months.

Ultimately, delegates expressed optimism about the vision agreed in Geneva this week, but there are concerns about how tough its implementation will be. According to Visbeck, the deal was much stronger on Tuesday, but “an unfortunate negotiation” meant that a couple of keys aspects were changed late in the day. One crucial change is that WMO is now ‘convening’ the implementation strategy rather than leading on it. Lacking one organization at the helm, the process of decision making could become that much harder. Secondly, a clause was added that says to all UN member states can weigh on each stage of the implementation plan before the final report is delivered to WMO in January 2011. “We didn’t achieve the maximum achievable”, says Visbeck.

In the meantime, however nations are charging ahead with implementing serivice-oriented climate science on their own steam. In July, Germany opened a national climate services centre in Hamburg, and the US is currently discussing plans for a national climate service in Congress and among relevant agencies.

Olive Heffernan

Posted by Olive Heffernan on September 04, 2009
Categories: 3a66c47d615e63162dcac400812ffa53, Climate prediction, Data, Olive Heffernan, WCC-3 | Permalink | Comments (0) | TrackBacks (0)

"People are going to be scratching their heads and saying, 'Wow, that's really sensitive.'"
Ken Buesseler of Woods Hole on a new finding that if the ocean's main carbon-recycling zone sank just 24 metres, seas would soak up significantly more CO2.

"When you decide how you invest money for climate adaptation, you should quickly come to the conclusion that ecology provides the best bangs for bucks - and that's even without taking into account the added benefits of saving biodiversity."
Pavan Sukhdev - an Deutsche Bank economist on secondment at UNEP - has translated damage to coral reefs and forests into multi-trillion-dollar financial losses.

“This is not something Japan will do on its own. The premise is an agreement that includes other countries such as China and India.”
Katsuya Okada, secretary-general of the Democratic Party of Japan, on the party's campaign pledge to cut greenhouse gas emissions to 25% below 1990 levels by 2020.

"The results should set at rest any apprehensions that India's greenhouse gas emissions are poised for runaway increase over the next two decades."
Government-backed report projects that India's emissions will more than triple by 2031, to between 4 billion tonnes and 7.3 billion tonnes.

Posted by Anna Barnett on September 04, 2009
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Tipping points - those critical thresholds in a complex system where a small nudge can cause a catastrophic response - are perhaps the most fearsome threats to the Earth’s climate, but they also haunt ecosystems, financial markets, and even sufferers of medical conditions such as epilepsy and asthma. A fascinating review in Nature today (subscription) sketches out the mathematical patterns on which many of these instances seem to be based, and describes giveaway signs that might warn us to change course before the system tips.

One common warning sign, for example, is flickering between the pre-tipping point state and the post-tipping point state. In climatology, abrupt changes traced in records of the Earth’s past suggest the planet has regularly gone through tipping points, such as the sudden warm-ups that change glacial periods into deglaciations. Earlier this year researchers reported in Nature Geoscience that rapid flickering signaled the end of Earth’s most recent cold spell, the so-called Younger Dryas period. The authors of the new review, led by Marten Scheffer of Wageningen University in The Netherlands, say that in a similar way, debilitating epileptic seizures can be preceded by frequent small symptomless seizures - the ‘flickers’ of the epileptic brain.

Continue reading "Why a climate crisis is like an epileptic seizure" »

Posted by Anna Barnett on September 03, 2009
Categories: Anna Barnett, Climate prediction, Earth science, Extreme Events | Permalink | Comments (1) | TrackBacks (0)

Following the recent discussion here on access to climate data, it’s been interesting to see the theme emerge in Geneva this week at the third World Climate Conference.

Almost 2,000 climatologists, weather forecasters and policy makers have come together to discuss the need to develop climate services that will enable adaptation to climate change. Better predictions of the changes to come will form the basis of such services. But in order to predict climate change more accurately and over smaller areas and time periods, investments in observations, research and computing will be necessary.

Delegates here are hoping that governments will commit to investing in these areas, but some say it’s also crucial that observational and modelled data become available to others. “It’s absolutely crucial. The societal importance far outweighs any commercial benefit”, says Ralph Rayner, chair of the scientific committee of the Global Ocean Observing System, an international effort to monitor marine variables. José Achache, director of the Group on Earth Observations, agrees. “We need more observations. Commerce and security are limiting the availability of some necessary and useful climate data”, says Achache.

That’s a bit of a thorny topic here, because some Met services package proprietary data and sell it to users. But it’s also a complex issue, says Vicky Pope of the UK Met Office, which operates as a trading fund. She says that a lot of data are made freely available by Met services, but that detailed climate data has commercial value. Pope also points out that nothing is ever free. "The tax payer is actually paying, and one of the reasons we charge users is so that the taxpayer doesn't pay too much".

Speaking at the conference on Monday, Jean-Jacques Dordain, director general of the European Space Agency, promoted sharing of climate data. “We are sharing our data. We are providing our data to African nations and are cooperating with other nations”

There have been vast improvements in data sharing in recent years, says Achache, but he warns that there is the risk of moving backward in certain areas. For example, some nations are calling for restrictions on data collected from ARGO oceanographic data buoys when they drift inside a country’s Exclusive Economic Zone, he says.

Kuniyoshi Takeuchi, director of the International Center for Water Hazards and Risk Management in Japan says that lack of access to climate data other than by climate professionals in rich nations is a problem. “Local ownership of climate information is needed for human empowerment” says Takeuchi.

Climatologist Jerry Meehl of the National Centre for Atmopsheric Researc in Boulder, Colorado says “it would make things a lot easier” if climate data were openly available to all, though he says that scientists probably should be allowed a grace period in which they have exclusive access to the results.

Olive Heffernan

Posted by Olive Heffernan on September 02, 2009
Categories: Data, Olive Heffernan, WCC-3 | Permalink | Comments (1) | TrackBacks (0)

Cross-posted from Geoff Brumfiel on The Great Beyond

Yesterday the Royal Society, Britain's premier scientific body, delivered its official view on geoengineering. Scientists analyzed a dozen different approaches and weighed their pros and cons. Then, being scientists, they plotted their results in a bizarre phase space that nobody could understand. Many a reporter, myself included, were scratching our heads when co-author Ken Caldeira popped this little gem up onto the screen:

(Note: error bars are purely symbolic. Huh?)

Now I want to be fair, the Royal Society report is actually very well written and it contains a lot of good information about the geoengineering proposals out there. But it's a nuanced take on a complex issue. So it's not surprising that you saw a range of headlines. The most inaccurate enthusiastic one by far, came from those lovely folks at the Register:

Boffins: Give up on CO₂ cuts, only geoengineering can work

The Financial Times landed on the other end of the spectrum:

Hopes dashed for geo-engineering solutions

And in between came everybody else:

Study says 'geoengineering' to flight climate likely, but risky (USA Today)

Royal Society warns climate engineering 'could cause disaster' (the Times)

World must plan for climate emergency-report (Reuters)

Investment in geo-engineering needed immediately, says Royal Society (the Guardian)

These headlines make the report look like a Kurosawa film, but most of the actual stories are pretty accurate in my opinion. The bottom line is that the Royal Society felt that the only sure way to save the planet is to reduce greenhouse gas emissions. But in the event of a global climate emergency, we should at least know the consequences of geoengineering.

You can read our coverage here.

Update: The Register headline was referring to an article in Physics World that came out the same day.

Update: I've included the updated diagram off the Royal Society website.

Geoff Brumfiel

Posted by Anna Barnett on September 02, 2009
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Climate scientists, weather forecasters and policy makers are gathered in Geneva this week to discuss the need for reliable climate predictions to help society adapt to climate change.

The third World Climate Conference of the World Meteorological Organization, which runs from 31 August to 4 September 2009, aims to produce a new global framework for delivering climate information to end users.

Scientists at the conference are hopeful that with sustained support for climate research and improved computing capabilities they could reliably predict climate impacts at much higher resolution – perhaps down to several tens of kilometres over the coming decades. The ultimate goal , and one that was voiced at last year’s World Climate Modelling Summit in Reading (which we covered here) is to produce climate predictions that are as reliable and useable as weather forecasts.

That would be a vast improvement on the projections available from today’s global climate models. Most of these enable estimates of how temperature, and other climate variables such as rainfall, will change over areas of several hundred kilometres up until the end of the century and beyond.

While a large focus of the conference is on improving climate modelling in order to make reliable predictions, delegates in Geneva are also discussing the need to tailor information to the needs of specific end-users.

“A forecast in not enough; our challenge is to communicate what we know that the future in a manner that can allow people to make decisions”, said Gro Harlem Brundtland, special envoy of the UN secretary-general on climate change, at the opening session on Monday. At the end of the 5-day conference, delegates will issue a declaration of their intent to establish a new global framework to meet this challenge.

But major advances will be needed in the science of prediction before climate information is of real service to society. “In 10-15 years we may have climate forecasts like we now have weather forecasts”, said Guy Brasseur of the National Centre for Atmospheric Research (NCAR) in Boulder, Colorado to delegates here on Monday. “We have the international vision, expertise and scientific commitment to deliver climate services”, said Brasseur, but he also warned of the difficulties in developing climate models of sufficiently high spatial resolution and reliability.

One hurdle is the massive investment needed to fund one or more supercomputers; others include accessing data and sustaining long-term observations. Despite these, several attempts to improve predictive capability are underway worldwide. One of these, being championed by Tim Palmer of the European Centre for Medium-Range Weather Forecasts is the concept of ‘seamless prediction’, in which one modelling system is used to predict atmospheric conditions on time scales varying from hours to decades. Other efforts, being headed by scientists from the UK Met Office and elsewhere, are focused on how climate change will pan out in the coming decades, and combines aspects of seasonal forecasting with centennial prediction (which I won’t go into now, but hope to come back to). Still another approach is Earth System Modelling, which attempts to model the whole earth system – including feedbacks - more comprehensively than climate models, at spatial scales of 150km across.

Scientists at the conference are excited at the possibility that such efforts will lead to greater predictability, but are also concerned that end-users could have unrealistic expectations of what that means. “We’ll never be able to produce absolute predictions of what will happen in the future”, says Vicky Pope of the UK Met office. She says that scientists must work within a risk management framework so that people don’t misuse the data. “We are nervous about the uncertainties and errors associated with the models we are using”, says Jerry Meehl of NCAR, adding “That needs to be part of the message that gets out with climate services”.

Olive Heffernan

Posted by Olive Heffernan on September 01, 2009
Categories: Climate prediction, Communicating Climate Change, Olive Heffernan, Regional climate, WCC-3 | Permalink | Comments (0) | TrackBacks (0)

Today The Guardian is unveiling their new 10:10 campaign, which pledges individuals, businesses and organizations to shrink their carbon footprints 10% in 2010. I'm heading down to Tate Modern to tweet the launch - follow @annabarnett, #1010.

Anna Barnett

Posted by Anna Barnett on September 01, 2009
Categories: In the News, Mitigation, Personal action | Permalink | Comments (2) | TrackBacks (0)