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Olive Heffernan

In a Correspondence in this week's Nature , James Lovelock and Chris Rapley propose a way of stimulating the Earth to cure itself from the disease of global warming.

Lovelock, author of the Gaia hypothesis and his co-author Chris Rapley, newly appointed director of the Science Museum in London, argue that drastic action is needed to help heal the planet, as they believe it is "doubtful that any of the well-intentioned technical or social schemes for carbon dieting will restore the status quo".

They turn to the ocean for solutions. Their proposed scheme involves placing vertical pipes some 200 meters long in the sea to pump nutrient-rich water from depth to the surface, thus enhancing the growth of algae in the upper ocean. The algae, which are key in transporting carbon dioxide to the deep sea and producing dimethyl sulphide involved in the formation of sunlight-reflecting clouds, should help to prevent further warming.

Although fertilizing the ocean with iron as a way of stimulating algal growth is being considered, the use of pipes to use the ocean’s existing nutrients as fertilizer is certainly novel.

Lovelock and Rapley admit that the scheme may fail or impact the ocean in negative ways, such as through further acidification (which is recognized a significant threat to marine life and water quality) but they argue that the stakes are so high now that we can’t afford not to try such a solution.

Read the news story by Quirin Schiermeier on the proposed scheme here.

Posted by Olive Heffernan on September 26, 2007
Categories: In the News, Mitigation, Olive Heffernan | Permalink | Comments (22) | TrackBacks (0)

Olive Heffernan

This week on Nature Reports Climate Change, Amanda Leigh Haag looks at how climate change is increasingly becoming an issue of national security, raising the alarm on issues of border control and immigration policy globally.

The feature details how regions likely to bear the brunt of climate impacts are already beginning to look to neighbouring states for potential resettlement deals, while less vulnerable nations are considering the likely spillover of large-scale migration from areas impacted by severe drought or flooding.

This raises some interesting issues, such as whether adaptation should focus on protecting the rights of people to live in their home, rather than offering relocation programmes, and whether these scenarios are inevitable without drastic measures to prevent further warming….but more on that shortly.

Posted by Olive Heffernan on September 26, 2007
Categories: Adaptation, Extreme Events, Features, In the News, Olive Heffernan | Permalink | Comments (10) | TrackBacks (0)

Posted by Oliver Morton on behalf of Roger Pielke Jr.

Last week Kevin Trenberth offered a perspective on Nature Climate Feedback where he suggested that "clarity is actually emerging" in the scientific community on the relationship of greenhouse gas emissions and hurricane activity. My perspective on this debate differs from Kevin's: Those in the tropical cyclone research community with different views on this subject remain as far apart as ever, and a community consensus beyond that presented in last year's WMO report has yet to emerge.

Here are a few additional comments following Kevin's piece:

1) The recent Holland (2007) paper in EOS dipped back into the same North Atlantic dataset that is the subject of intense debate to find that the area where storms have formed appears to have changed over time, observing that the dataset shows "the eastward spread of cyclone developments into the equatorial Atlantic." Of course, those who argue that changes in observational systems are responsible for the increase in storm frequency found in the dataset can equally apply this logic to the location where storms are first observed. That is, they would argue that as observations have improved, more storms have been observed to have formed in the eastern Atlantic. Holland's paper therefore provides ample support for both sides of the debate, which is not surprising since its analysis depends upon the exact same dataset that has been contested. Whether or not landfall rates are a constant proportion of basin activity remains a scientific frontier in hurricane climatology.

2) What has been neglected in the debate - by both sides - and is implicit in Holland (2007) is that whatever the cause of increased activity in the North Atlantic, the increase has taken place in the eastern Atlantic far from where landfalls occur (and this holds for storm counts and measures of intensity). On this point everyone seems to agree (see this exchange between ClimateAudit's Steve McIntyre, who pointed out this trend on his blog and Georgia Tech's Judy Curry, who is a collaborator with Holland). What this means is that if global warming has indeed led to an increase in North Atlantic hurricane activity, then it has necessarily (and ironically) had the effect of making the United States relatively safer from hurricanes as the proportion of total storms that makes landfall has decreased dramatically. (That is, landfalls show no trend while basin activity has increased due to global warming according to Mann et al. 2007 cited by Kevin). Imagine that headline - "Global Warming Protects U.S.from Increasing Landfalls"! Strange but true, but that is exactly the right message to take if Holland (2007) is taken at face value.

Continue reading "The Hurricane-Global Warming Debate, No Clarity Yet" »

Posted by Oliver Morton on September 24, 2007
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Kevin Trenberth

The recent Asian Pacific Economic Cooperation (APEC) summit has brought further attention to climate change and what, if anything, to do about it. In spite of the IPCC findings that global warming is “unequivocal”, doubt remains in some quarters about the reality of climate change and the human cause. Issues are continually raised that have no basis, as highlighted by the recent Commentary from Syun-Ichi Akasofu in the Wall Street Journal.

Akasofu immediately starts out on the wrong foot by claiming there are two sides, those of believers and non-believers, but it is not a matter of belief, it is a matter of scientific facts! He further fails to understand the nature of the IPCC process and the extensive reviews in which all comments are addressed rigorously as the report is developed over three years. Contrary to the claim, there is no assumption by IPCC that recent warming was due to the increased greenhouse effect from increasing human produced carbon dioxide. Rather, climate models that run with and without the human-induced changes in atmospheric composition demonstrate that human warming has emerged from natural climate variability since about 1970.

Over the past 500,000 years or so, temperatures, carbon dioxide and methane have gone up and down more or less in tandem through the major ice ages and interglacial periods, as shown in ice cores. As detailed in a Real Climate blog post on this topic, in the absence of human intervention, these changes happen over time, but not at the rate at which CO2 is currently increasing in the atmosphere. Scientists know that carbon dioxide and methane changes follow rather than cause these changes in temperature between glacial periods, but they also know that these changes in greenhouse gases amplify a relatively weak forcing to help drive temperature change. To suggest otherwise, as Akasofu does, is misleading at best.

Akasofu then trots out the mistaken view that the “hockey stick” curve of temperatures over the past 1000 years showing an upward bend at the end has been discredited. In fact, it has been reinforced in the latest IPCC report, although it is given less emphasis as it is now backed up and confirmed by evidence from multiple independent studies.

He further claims that natural climate variations have been forgotten and attributes recent warming to the “rebounding effect from the little ice age”, but fails to realize that natural climate variability also has a cause. While it is true that we do not have the measurements to show what was happening in the ocean during this time, for instance, we have good reason to believe that natural internal variability played a role. To the extent that the "Little Ice Age" and "Medieval Warm Period" can be meaningfully defined, there has been much work showing that the main variations can be explained in terms of the response of the climate system to natural variability in solar and volcanic events that would have influenced surface temperature. And warm periods in the past, such as the warming in the Greenland region in the mid-twentieth century, were not global in contrast to recent warming, which is.

Climate models are not perfect, but they are useful tools for quantifying the effects of various climate processes and drivers of climate change. Akasofu decries the confused state of climatology, but it is he who is really confused, and his article only serves to confuse the general public. It is sad that a once distinguished newspaper published such misleading half-truths without verifying them.

Kevin Trenberth

Posted by Olive Heffernan on September 19, 2007
Categories: Climate Science, Communicating Climate Change, In the News, Kevin Trenberth | Permalink | Comments (39) | TrackBacks (0)

Kevin Trenberth

The situation on how hurricanes have changed and will likely change in the future are outlined in my recent Scientific American article, but may seem as murky as ever to the public although clarity is actually emerging.

A recent news report in the Press Register outlines some sources of confusion related to just how well the past record is known. It cites work by Landsea that relied on numbers of land-falling storms as a way to calibrate the Atlantic hurricane record, and which concluded that there may be an undercount of 3.2 storms per year prior to 1966. The most recent Eos Transactions has two articles that follow up and point out why use of land-falling storms is misleading [Holland 2007; Eos 88 (36) 348-349] and that the conclusions of increased activity do not change anyway [Mann et al., 2007; Eos 88 (36) 349-350].

The Holland article points out that there are good reasons why the fraction of storms making landfall should change, both because of natural variations and especially if the climate changes. The Mann et al. article adopts the Landsea-suggested changes for the past as a “what if” test and goes on to show that even a substantial underestimate of early 20th century storms does not change the significance of the increase in activity since 1994. Nor does it change the strong relationship with observed sea surface temperatures (SSTs) in the region; the SSTs have a much more reliable observational record and have clearly increased.

Surprisingly, none of these studies refers to what seems to me to be the most definitive analysis of the likely missed storms in the historical counts by Chang and Guo (2007) in which they analyze in detail the actual ship tracks in the past compared with modern tropical storm tracks. To quote their main conclusions: “It is estimated that the number of tropical cyclones not making landfall over any continent or the Caribbean may have been underestimated by up to 2.1 per year during 1904–1913, with this number decreasing to 1.0 per year or less during the 1920s and later decades. Our results suggest that the characteristics of North Atlantic tropical cyclone track statistics might have changed during the 20th century.”

In 2007 the tropical storm season has been fairly normal in many respects up to now. Only 3 hurricanes have been recorded (versus average 3 to 4) but two were category 5 storms, and that is highly unusual. Forecasts of hurricane activity by NOAA and Bill Gray continue to forecast substantially above normal activity in the Atlantic. To me, observing the events thus far, the incredibly intense convective activity in the Indian Ocean from May to July was an important and totally overlooked factor. The subsequent heavy rains and flooding in India and China were no doubt related. The fact that Atlantic hurricane activity is influenced by events in the Indian Ocean seems to be overlooked by the hurricane forecasters.

Kevin Trenberth

Posted by Olive Heffernan on September 17, 2007
Categories: Climate Science, Hurricanes, Kevin Trenberth | Permalink | Comments (3) | TrackBacks (0)

Cross posted from The Great Beyond

On Friday, the US Geological Survey put out a press release about its new findings on polar bears and their future, and the press responded en masse: Google offers hundreds of stories filed over the weekend. The reports’ conclusion (AP | New York Times) is that diminishing sea ice is a serious problem for the bears, with two thirds of them at risk over the next fifty years – maybe more if, as the report recognises, current estimates of ice loss are too conservative. Most quoted quote: "As the sea ice goes, so goes the polar bear" -- Steven Amstrup, the lead author of the new studies.

Some bear populations, such as those of Alaska, are expected to die out completely, which is naturally enough the lead in the Anchorage Daily News. If you’re a polar bear, the place you want to be is what the USGS calls the “convergent ice ecoregion” (a term that doesn’t seem to turn up in the news); this is where the currents pile up ice that can persist for years on the northern shores of the Canadian islands and down the eastern side of Greenland. You don’t want to be west of Greenland or in Baffin Bay, where the ice is seasonal ice and likely to vanish, or on the north shores of Russia and Alaska, where the currents move what ice there is away from the shore (the “divergent ice ecoregion”).

The reports are part of the process by which the US government will decide whether to put polar bears on the endangered species list (earlier Nature story). Geoffrey Lean, at the Independent, pulls the USGS report together with his paper’s investigation into polar bear hunting, which is apparently on the increase. Lean and others also bring up a meeting of religious, scientific and political leaders that’s been going on in Ilulissat , where “leaders of Christian, Shia, Sunni, Hindu, Shinto, Buddhist and Jewish religions took a boat to the tongue of the glacier for a silent prayer for the planet” while Robert Correll, chairman of the Arctic Climate Impact Assessment, warned of “a massive acceleration of the speed with which these glaciers are moving into the sea,” according to Paul Brown in the Guardian.

Meanwhile, almost all of the stories also mention the current reduced area of Arctic sea ice, which this year has already reached a record low and is expected to keep shrinking for a week or so more. The US National Snow and Ice Data Center is keeping a close eye on the situation with regular updates and a lot of interesting data, not to mention a really nice animation that shows how the ice cover evolves over many years (found via and easily seen at Steinn Sigurdsson's Dynamics of Cats) which explains more about the convergent and divergent ecoregions than a static map ever could.

Images: Grzegorz Polak, distributed under Creative Commons license; Wikimedia

Posted by Oliver Morton on September 10, 2007
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Cross posted from The Great Beyond

The BBC, it seems, is damned if it does and damned if it don’t. Having abandoned plans for a day long global warming special “which would have involved viewers in a mass ‘switch-off’ to save energy” it has taken fire from all sides (BBC News). As its own reporting notes it has been accused of “cowardice” by environmentalists. However, critics including some senior voices within the corporation had previously slammed the planned ‘Planet Relief’ programme as a violation of the commitment to impartiality enshrined in the BBC’s charter. The BBC claims the show was scrapped not due to impartiality concerns but because audiences “are most receptive to documentary or factual-style programming as a means of learning about the issues surrounding this subject”. So maybe they’ll just be showing ‘An Inconvenient Truth’ on loop?

For those not based in the UK it is probably worth noting that the BBC is funded by a ‘licence fee’ levied on every television owner. It is “forbidden from expressing an opinion on current affairs or matters of public policy other than broadcasting” (BBC guidelines). The scrapping of the show follows heated debate within the BBC over its stance on climate change. One of the BBC’s own editors earlier this month said it was "not the corporation's job to save the planet" (Daily Mail). The blogosphere has gone into pretty predictable overdrive.

Another employee, the BBC’s Head of News Peter Horrocks, wrote a blog entry on the topic in which he said “It is not the BBC's job to lead opinion or proselytise on this or any other subject.” However Horrocks also says “there is an increasingly strong (although not overwhelming) weight of scientific opinion in favour of the proposition that climate change is happening and is being largely caused by man”. I’m not sure many climate scientists would agree that the weight of opinion was “not overwhelming”. Opposition politician Chris Huhne, environment spokesman for the Liberal Democrats, certainly wouldn’t. “The consensus about global warming in the science community is now overwhelming,” he says (Independent), “so accusing the BBC of campaigning on such an undisputed threat is like suggesting it should be even-handed between criminals and their victims.”

Image: Getty

-- Daniel Cressey

Posted by Oliver Morton on September 07, 2007
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Olive Heffernan

Having been off the airwaves for a while, I’m back with some further musings on climate change surveys, which (unwittingly) seems to be becoming a bit of a pet topic of mine.

Today saw the launch of ‘Future Friendly’, a partnership between four British NGOs, the Energy SavingTrust, Global Cool, Waste Watch and Waterwise and multinational consumer goods giant Protocol and Gamble aimed at helping and inspiring people to live more sustainable lives.

While the initiative, launched this morning in London, sounds laudable, it smells strongly of corporate greenwash.

The idea is that, by using products displaying the Future Friendly logo, shoppers will save energy, water or reduce waste. In tandem with the launch of the ‘Future Friendly’ brand logo, which will appear on certified products as of next week, the partnership announced the results of a survey on citizen’s attitudes towards sustainability and a ‘Future Friendly’ award, given to individuals who are heroes in encouraging sustainability on a local level.

The products that have thus far received the green stamp of approval include Ariel, Lenor, Fairy Liquid, Fairy Active Bursts and Flash, all, interestingly, manufactured by Proctor and Gamble. The criteria on which their green credentials are based seem a little dubious; for instance, Ariel is “asking the nation” to turn the dial down to 30 degrees to save up to 40% of the energy used per load, while Flash All Purpose Cleaner “enables you to do your cleaning with cold water”. So, it seems their sustainability criteria all rely on things that consumers have to do themselves while using the products, rather than the products themselves having ‘greener’ ingredients or packaging or being manufactured in some more efficient way.

Then comes the survey on consumers’ attitudes to sustainable living . Conducted by think tank The Future Laboratory, the results are based on a multiple choice questionnaire issued to 1,000 people in 12 UK counties this autumn. The main finding is that ‘green is the new norm’ and that environmental issues are galvanizing 'a new breed of citizen’ in the UK committed to living a sustainable lifestyle. It’s great to have individuals feeling friendly about the environment and about its future, but as is the case with so many of these surveys, the questions tend to polarize opinion and naturally frame opinion within the context of predefined questions. In relation to climate change, for example, 41% of respondents said individual action was the only way forward in solving the problem. I’d like to know what the alternatives were, but strangely there wasn’t a question relating to climate in the questionnaire, so that one remains a mystery.

Having said all of that, I think we should commend anything that encourages the public to lead more sustainable lives as do the ‘Future friendly’ awards. Developed by the partnership, they grant £10,000 to each of four winners to help fund their efforts to encourage sustainable living. But we should also bear in mind that to live sustainable lives, we’d have to each reduce our emissions by around 90%, something that requires a lot more than using fairy liquid…

Olive Heffernan

Posted by Olive Heffernan on September 06, 2007
Categories: Communicating Climate Change, In the News, Olive Heffernan, Opinion | Permalink | Comments (1) | TrackBacks (0)

Cross posted from The Great Beyond

Hurricane Felix, currently menacing Central America, has become the second storm of 2007 to be rated category five – the highest wind speed category (updates). The Daily Telegraph says it was upgraded on Sunday from category two to category five in 15 hours – one of the fasted jumps on record. There is some debate over what this might mean. Jean-Noel Degrace, expert at Meteo-France told the AFP, “The fact that there have already been two intense storms marks out 2007 as an active year.” Mark Saunders, lead scientist with the Tropical Storm Risk, only went so far as to say it was “unusual but not unprecedented” to have a category five at this point in the hurricane season.

Despite the US National Hurricane Center having already predicted this to be an “above-normal” hurricane season, some people are still getting excited, perhaps over excited. “I can't get over these numbers: The 1980s saw three official Category 5 hurricanes. The 1990s saw two. The 2000s, so far, have seen eight, all clustered from 2003 to 2007. In this context, the past five years certainly look like a scary anomaly compared to what has come before,” said blogger Chris Mooney, whose book “Storm World” deals with “Hurricanes, politics and the battle over global warming (Nature review, subscribers only). Could these hurricane numbers be linked to global warming?

Climate modeller William M. Connolley is having less than none of it. “If you want to know if its got warmer, then hurricanes are clearly a poor indicator - the record is too noisy,” he says. “And we have a far better record: that of the temperature. If you want to know, conversely, if GW is going to lead to more or deeper or scarier hurricanes, then counting numbers by decade isn't a good idea either.” Their disagreement continues in the comments of Connolley’s blog.

Whatever the truth of the situation, it is proving grist to the mill of those looking for a liberal (for which read global warming expounding, environmentalist) bias in the media – NewsBusters for example. Mooney has also pulled together a nice set of links on Felix.

Image: National Oceanic & Atmospheric Administration

-- Daniel Cressey

Posted by Oliver Morton on September 04, 2007
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