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Olive Heffernan

Apparently, an all white computer screen, such as an empty Word page, or the Google page, uses 74 watts to display, whereas a black screen consumes only 59 watts. So claimed Mark Ontkush in a post on the ecoIron blog in January. Doing a few back of the envelope calculations based on numbers of users per day and wattage for different coloured screen from EnergyStar, Ontkush figured that the energy saving would be 750 Megawatt hours per year if Google had a black screen.

And so, with the help of Heap Media, Google created a black version of its search engine, called Blackle.

The Wall Street Journal did some of their own calculations, which challenge the energy-saving claims of Blackle. In a blog post from May, they point out that the "savings are most likely to accrue from older CRT (cathode-ray tube) monitors, rather than the more modern, energy-efficient LCD (liquid crystal display) screens that dominate the market (representing three quarters of all monitors world-wide as of last year, by some estimates)." They did some tests using Blackle, Google and the New York Times on a CTD and LCD monitor and found the difference "so slight as to be within the margin of error for the power meter".

Since then, it's been blogged about here, here and here. Anyhow, check it out - it's certainly novel, whether or not it's especially efficient.

Olive Heffernan
News Editor
Nature Reports Climate Change

Posted by Olive Heffernan on July 26, 2007
Categories: In the News, Mitigation, Olive Heffernan, Personal action | Permalink | Comments (20) | TrackBacks (1)

Olive Heffernan

Much like the rest of Britain, I’m beginning to wonder if it’s ever going to stop raining. And despite feeling slightly miffed at an appalling excuse for a summer, I realise I'm lucky to be based in slightly soggy London, given that large areas of the country are currently besieged by some of the worst flooding in recent British history.

Calling it a ‘21st century catastrophe’, Michael McCarthy at the Independent writes that “Britain is suffering from a wholly new type of civil emergency: a disaster caused by 21st-century weather,” which has left more than a third of a million people without drinking water, nearly 50,000 people without power, thousands more people homeless and caused more than £2bn worth of damage so far.

Britain is not alone in experiencing extremely heavy rainfall. As reported on MSNBC, “parts of China had the heaviest rainfall since records began, killing more than 700 so far this year. Hundreds of thousands have been displaced by flash floods in southern Pakistan.”

While these single events cannot be attributed to climate change, many are questioning if the flash flooding is a sign of what is in store for the future. And scientists have some of the answers.

In a paper coming out in Nature this Thursday, Francis Zwiers of the Canadian Centre for Climate Modelling and Analysis in Toronto and colleagues present the first evidence that human-generated greenhouse gas emissions have altered rainfall patterns in the 20th Century. In the region between 40 and 70 degrees North, covering northern Europe, Russia and parts of North America, rainfall increased by 62 millimetres per century between 1925 and 1999. Zwiers and colleagues say that 50-85% of this increase can be attributed to human activity. For further discussion and comments on the paper, there’s a news story by my colleague Daniel Cressy on News@Nature. And it’s also been picked up by the BBC.

And a recent paper published in Science in June suggests that global warming may result in even more rainfall worldwide than is currently evident in climate model simulations. Frank J. Wentz of Remote Sensing Systems in Santa Rosa, California and co-workers compared global satellite data from 1987 to 2006 and found that rainfall increased at the same rate as atmospheric water vapour per degree Celsius of surface warming. Climate models had projected a dampened response of rainfall to global warming owing to a decrease in surface winds, but Wentz and colleagues found that surface winds have in fact become stronger, leading to heavier rainfall (more on this in Nature Reports Climate Change soon).

Coming back to Britain… the situation is likely to worsen over the next 24 hours. Eight severe warnings have been issued covering the rivers Thames, Severn and Ouse, in particular for towns such as Gloucester, Tewkesbury, Oxford, Abingdon, Reading and Bedford. Fifty other flood warnings are in place across England and Wales.

To see the areas generally most at risk of flooding in England and Wales, visit the Environment Agency’s flood map online, where you view flood risk by postcode. For an up to date interactive on the current situation, the Guardian has quite a snazzy interactive highlighting areas most at risk.

Olive Heffernan
News Editor
Nature Reports Climate Change

Posted by Olive Heffernan on July 24, 2007
Categories: Climate Science, Extreme Events, In the News, Olive Heffernan | Permalink | Comments (3) | TrackBacks (0)

Kevin Trenberth

A recent paper published by Gaertner et al. in Geophysical Research Letters (GRL) (in press as of 12 July 2007) explores the possibility for tropical cyclones to occur in the Mediterranean area in the future with global warming. It has been featured in the Times. The paper correctly points out that tropical cyclones have recently ventured into some unusual places with Catarina on the east coast of Brazil in March 2004 and Vince making landfall in Spain in 2005. Gaertner et al. use an ensemble of regional climate models to assess new locations of tropical cyclone occurrence. They find an increase in extremes of cyclone intensity over the Mediterranean Sea in regional model climate change scenario simulations. This increase, they claim, is clearly related to tropical cyclone formation, revealing for the first time a risk of tropical cyclone development over the Mediterranean Sea under future climate change conditions.

The regional model framework for this study is one limitation as it may not create the correct large-scale atmospheric circulation across the region. In particular, the Mediterranean climate in summer is one of clear skies and sunny days associated with the overall global monsoon circulation, such that the upward motion and rains in southern Asia are linked to the subsiding air over the Mediterranean that makes for a very stable environment unfavorable for storms. Unless that link is properly simulated (and it may not be, especially in a regional model) the vertical atmospheric temperature and wind structure are unlikely to be right.

The authors are aware of the summer difficulties and so they choose September as the time for the simulations. This has the advantage that the sea surface temperatures (SSTs) are highest then. The sun has been beating down all summer, but it tends to form a shallow layer of warm water and whether there is adequate heat below the surface is also a critical question. As cyclones form they churn up the ocean, bringing cold waters up from below and cool the ocean, creating a cold wake. In this work the SSTs were specified and fixed and this was not allowed to happen.

Moreover, by September, the mid-latitude westerlies have set in and the winds in the upper troposphere are typically over 20 m/s, so the wind shear environment is generally unfavorable for such storms. It is possible that the weather could change enough to relax the winds for just long enough to open a window for tropical cyclones but the odds are not high. This is the extratropics, after all.

All these questions remain. Nonetheless, with higher SSTs it does seem likely that cyclones would be more vigorous. But whether they are truly tropical or not is a key issue. The paper does not comment on water vapor: the Mediterranean Sea is surrounded by land where the air is drier and this can cause storms to run out of moisture and peter out. Nor does it mention rainfalls and flooding: a chief characteristic of tropical cyclones is the heavy rainfalls of several mm per hour. Nonetheless, warm core storms have been noted in the Mediterranean and are colloquially referred to as “Medicanes”.

For further discussion of tropical cyclones and climate change, see my recent article in Scientific American here.

Kevin E. Trenberth
Head of the Climate Analysis
US National Center for Atmospheric Research

Posted by Olive Heffernan on July 24, 2007
Categories: Atmospheric Science, Climate Science, Hurricanes, In the News, Kevin Trenberth | Permalink | Comments (0) | TrackBacks (0)

Posted by Olive Heffernan on behalf of Alex Witze

This week’s issue of Nature has several news stories related to climate change.

First up, we’ve got a look at the bill introduced recently in the US Congress by Senators Jeff Bingaman (New Mexico) and Arlen Specter (Pennsylvania). It’s the latest in a rush of climate bills that have been coming before Congress in recent months, spurred by the Democratic takeover in January. The Bingaman/Specter plan isn’t as stringent as other bills that would slash emissions more drastically, but has the backing – at least so far – of groups that don’t typically support emissions cuts, like utility companies and labor unions. So some observers think this new bill could form the backbone of an eventual compromise for US climate-change legislation.

It’s hard to keep track of all the bills that are out there these days. Some handy places to check for comparisons are a Senate website and the World Resources Institute chart. We might have put the latter chart into the news story this week, but it used old numbers for a draft version of the Bingaman/Specter bill, and is being updated now with the final version.

Another chart didn’t make the news section this week – that’s a figure appearing in the July 13 issue of Science, in a Perspectives piece by Peter Cox and David Stephenson of the University of Exeter. It’s a simple chart showing how uncertainties in model predictions change over time, with the total uncertainty being the least 30 to 50 years in the future. The Cox/Stephenson paper basically argues that climate model projections need to become more useful and relevant on this time scale; any changes for the next 30 years are essentially already ‘in the system’, and changes after about five decades out are too uncertain to say anything really meaningful about. Focus on that sweet spot, they say, and climate modelers are serving society’s needs better.

The original Science piece is here; our news piece, which also wraps in a tiny bit of the newly-released US Climate Change Science Program report on climate scenarios, is here.

Alex Witze
Senior News and Features Editor
Nature

Posted by Olive Heffernan on July 20, 2007
Categories: Alex Witze, In the News | Permalink | Comments (1) | TrackBacks (0)

Olive Heffernan

I've been asked to chair a debate on climate change in Malta in November. The debate, taking place at the Pacem in Maribus XXXII conference on 5-8 November, is being hosted by the Institute of Marine Engineering, Science and Technology and is aimed at engaging your marine professionals in climate issues.

So, the debate will be looking at some of the issues surrounding climate change of particular relevance to this community, such as the respective role of engineers and scientists in mitigating and adapating to climate change, the role of the shipping industry in contributing to and in mitigating climate change, and the role of individual action versus government leaders in effecting change.

I'd welcome any comments and suggestions and of course if you're interested in joining us or know of others who would be, check out the programme at the link above or register for the debate.

Posted by Olive Heffernan on July 13, 2007
Categories: Communicating Climate Change, Conferences and Meetings, Olive Heffernan, Opinion | Permalink | Comments (5) | TrackBacks (0)

Olive Heffernan

HSBC announced the results of their international survey on public attitudes to climate change in London this morning.

The survey found a gulf between public opinion on climate change in developed and developing nations, with people in developing economies showing greater concern, commitment and optimism in solving global warming compared with respondents in developed countries. The results challenge the myth of committed developed world countries leading on climate change with reluctant developing nations trailing behind, said Jon Williams, Head of Group Sustainable Development at HSBC, speaking at the event.

Conducted in 9 countries (UK, France, Germany, USA, Mexico, Brazil, China, Hong Kong and India) during April 2007, the internet survey asked 1000 participants in each nation to rank their level of agreement on four statements on a 1-7 scale (with 1 representing strong disagreement and 7 representing strong agreement) as follows:

“Climate change and how we respond to it are among the biggest issues I worry about today”.

“The people and organisations who should be doing something about climate change are doing what is needed”.

“I am personally making a significant effort to help reduce climate change through how I live my life today”.

“I believe we can stop climate change”.

Europeans, it seems, are a bunch of ‘sceptical pessimists’, with the lowest scores overall. While we are reasonably concerned about climate change, we have little confidence, optimism or commitment in solving it. Only 6% of UK respondents agreed with the statement “I believe we can stop climate change” compared with 18% in the US and 45% in India.

UK respondents also showed a surprising lack of belief that they are making a significant effort to reduce their personal carbon footprint, in contrast to 44% of those interviewed in China, 47% in both Brazil and India and 23% in the US. And why would we? It seems, according to the survey, we’re not really that concerned about climate change, being far more freaked out by terrorism. On levels of concern, UK citizens (22%) and Germans (26%) scored lowest.

In contrast, Mexico, Brazil and India make up the ‘committed concerned’, with approx 60% worried about climate change. Almost half are certain they are making the necessary changes to avert a climate catastrophe. Some of the findings are somewhat less surprising – US citizens are ‘sceptical optimists’ – more confident and optimistic than their cynical European counterparts that we will solve the global warming problem. China and Hong Kong, the ‘committed confident’, show the greatest belief that the people and organisations responsible are already doing what they should be doing to tackle the problem.

Continue reading "Developing nations lead on concern for combating climate change, shows survey " »

Posted by Olive Heffernan on July 12, 2007
Categories: Communicating Climate Change, Conferences and Meetings, Olive Heffernan, Opinion | Permalink | Comments (4) | TrackBacks (0)

Posted by Olive Heffernan on behalf of Kevin Trenberth

Given that human induced climate change is with us, a looming challenge is to predict just what the climate will be. To date, there are no such predictions although the projections given by the Intergovernmental Panel on Climate Change (IPCC) are often treated as such. The distinction is important. A paper presented at the International Forecasting Symposium in New York City in late June 2007 by J. Scott Armstrong and K. C. Green is highly critical of IPCC procedures and "forecasts" for not being based on "evidence based" procedures as outlined in an earlier 2001 book of his. It is true that IPCC does not refer to Armstrong's work as it has dubious relevance.

In fact IPCC does not do forecasts, as explained in my earlier post. The IPCC instead proffers "what if" projections of future climate that correspond to certain emissions scenarios. Armstrong has evidently read only chapter 8 of the IPCC Working Group I report and has therefore overlooked the fact that the other chapters address many of the things he is critical of.

In particular there is clear evidence (“warming is unequivocal”) that climate is changing in ways consistent with the climate forcings. Also, the projections are for all aspects of climate, not just global mean temperature. It has been said that “All models are wrong, but some are useful”. The Armstrong forecast of no change is not useful when the system is already changing in ways consistent with human influences on the composition of the atmosphere. Nonetheless, improvements in forecasting procedures are always welcome.

Bob Carter, a climate change doubter in Australia, has written a distortion of all this in the Courier Mail, issuing various attack against the science of climate change. Andrew Ash has written a rebuttal of these comments.

Another key point is that unlike forecasts based on past experience, weather forecasts are based on numerical weather prediction models and rigorous procedures, not empirical methods, although the latter are used to provide added value (e.g., based on known biases in the model). My own presentation at the same conference provides a description of weather and climate prediction.

Continue reading "Global Warming and Forecasts of Climate Change " »

Posted by Olive Heffernan on July 11, 2007
Categories: Climate Science, Conferences and Meetings, Kevin Trenberth | Permalink | Comments (12) | TrackBacks (0)

Posted by Olive Heffernan on behalf of Quirin Schiermeier

The sun, despite claims to the contrary, is not a factor in recent climate change.

Nature had a news article last week about a paper – and the reactions to it - by Mike Lockwood and Claus Froehlich. Their comprehensive (and conclusive) (re)-analysis of solar trends concludes that the sum of natural changes in solar activity since 1985 would have cooled our climate, were it not for the strong warming effect of increased greenhouse gas concentrations.

The findings, published in Proceedings of the Royal Society A, went online yesterday and have triggered a world-wide echo in the media and in the climate-crazy blogosphere.

That is surprising inasmuch the data are by not what you would call a scientific breakthrough. Indeed, most climate scientists will hardly consider the findings particularly new or surprising. Granted, bringing into line solar observations and measurements (and associated theories) collected during the 20th century is anything but trivial. But no matter how one looks at the issue, existing data were long supposed sufficient to disprove the only seemingly reasonable idea that global warming might be the natural result of increased solar activity.

Lockwood and Froehlich’s study does however go a step further. The two find that the correlation between solar activity and temperature trends post-1985 is actually negative. This means that changes to the sun (including cosmic ray intensity, for that matter) have contributed Less than Zero to the recent sharp rise in average global temperatures.

End of debate? Unfortunately no, I would guess. The inaptly so-named ‘climate sceptics’ who are keen to let mankind off the global warming hook, will not easily abandon this battle-tried warhorse. A natural sun-climate link, albeit invisible and unverifiable, is just the most persuasive among the set of quasi-plausible arguments with which upright eco-optimists attempt to dismiss as a (left-wing? anti-liberal?) conspiracy theory mankind’s responsibility for global warming. The ‘Great Global Warming Swindle’ documentary, to be aired tomorrow in Australia, is just the most-recent example of such attempts to argue that climate change is the effect of the sun.

To further confuse things and the public, solar changes do seem to have had an impact on past climates. Moreover, it is at least not impossible that cosmic ray intensity does influences clouds and climate. There’s nothing wrong with investigating these things - that’s how science goes. But blaming the sun for recent global warming is no science-backed position anymore – it is deliberate disinformation.

Quirin Schiermeier
German Correspondent
Nature

Posted by Olive Heffernan on July 11, 2007
Categories: Climate Science, Climate variability, In the News, Quirin Schiermeier | Permalink | Comments (29) | TrackBacks (0)

Olive Heffernan

In the latest issue of Nature Reports Climate Change, there’s an interesting Commentary by a group of atmospheric scientists who argue that, in assessing the skill of climate models by their ability to reproduce warming over the 20th Century, the latest IPCC Working Group I report may give a false sense of the climate models’ predictive capability.

In ‘Quantifying Climate Change – Too Rosy a Picture?’, Stephen Schwartz of the Brookhaven National Laboratory in Upton, New York; Robert Charlson of the University of Washington, Seattle and Henning Rodhe of Stockholm University, Sweden say that, as it stands, the narrow range of modelled warming misrepresents the certainty with which past temperature changes can be reproduced.

The temperature changes over the 20th Century summarized in the IPCC report represent results from 58 runs with 14 climate models. Although the models fared well at simulating past temperature changes (see Figure 2 for the comparison between simulated and observed warming), Schwarz and co-authors point out the uncertainty range is only half what it would be if uncertainties in the factors driving simulated climate change were accounted for – e.g, cooling by aerosols.

Richard Kerr has an interesting news piece on this Commentary in the July 6 issue of Science entitled ‘Another global warming icon comes under attack’. Kerr’s take on it is that, unlike climate skeptics taking cheap potshots at their choice picks of climate science, the Commentary by Schwarz and co-authors represents a group of mainstream atmospheric scientists challenging an emerging icon of global warming, with climate scientists giving some ground.

Co-author Charlson points out clearly in the Science news piece that “it is not a question of whether the Earth is warming or will continue to warm” under human influence. Rather, Schwarz and co-authors maintain that it is important to give an accurate picture of the range of sensitivities of current models, so that we have a better gauge of what the future might hold.

Kerr reports that IPCC authors say the group has a point, but that their latest WGI report, if read thoroughly, does reflect the uncertainties highlighted in the NRCC Commentary. We will have a response from IPCC authors on the Commentary soon, and will update you when we do....

Posted by Olive Heffernan on July 10, 2007
Categories: Climate Science, In the News, Olive Heffernan, Uncertainty | Permalink | Comments (0) | TrackBacks (0)

Posted by Olive Heffernan on behalf on Paty Romero Lankao

For the first time in human history, in this year half of the world's population lives in urban regions. This proportion is expected to go up to more than 60 percent by 2030. In an effort to understand the urban vulnerabilities to climate change, and to highlight innovative solutions to increase cities resilience, the Rockefeller Foundation, along with the Center for Sustainable Urban Development (CSUD), of The Earth Institute at Columbia University, is sponsoring a week-long discussion (July 8-13) on “Building for climate change resilience” within of month-long series of themed conferences aimed at promoting solid innovations for the many environmental and societal challenges facing urban world.

More to follow after the event next week....

Posted by Olive Heffernan on July 10, 2007
Categories: Adaptation, Conferences and Meetings, Paty Romero Lankao | Permalink | Comments (0) | TrackBacks (0)

Olive Heffernan

This weekend saw the biggest global media event of all time…and by far the largest climate awareness event in history. Al Gore’s concerts for a climate in crisis were watched by an estimated 2 billion viewers (at the events, on TV and an unprecedented number online) and took place over 24-hours on seven continents (thanks in part to the somewhat lesser known band Nunatak taking a break from field work!)

With bands blaring from Sydney, Tokyo, Shanghai, Hamburg, London, Johannesburg, New York, Rio de Janeiro and the Antarctic, the aim of Live Earth was to urge people to make a personal commitment to combating climate change by taking a ‘seven point pledge’.

There were also frequent calls asking people to lobby government for change in legislation, but the specifics of this goal were somewhat vaguer. The level of awareness raising at the heart of Satuirday's concerts is urgently needed, as evidenced in the results of recent polls, one of which apparently shows that a majority of Britons and are more concerned by dog poop than global warming and believe that scientists are still questioning climate change (although see John Sauven’s alternative analysis in the Guardian). Another recent survey suggests that half of teenagers are just not that interested and even fewer feel personally empowered to change.

The event and its participants have received no end of criticism for their carbon-intensive ways. One comment on BBC’s Newsnight blog provided the anology “You wouldn’t hold a hog-roast to promote vegetarianism”.

Fair point, but if you want to get people to listen to a call for change, punctuating it with Kasabian, Keane and the Red Hot Chili Peppers is definitely not a bad approach. Yes, the participants lead especially carbon intensive lifestyles (though the Chili's have at least been offsetting for years)…but surely that's part and parcel of the point the event is making….rock concerts happen, people drive SUVs, we have unsustainable lives...and that needs to change.

Whether Live Earth as an event can instigate that change is another question. Without a doubt, the concerts have caught the attention of the public and the media across the globe. As one of 60,000 at the Wembley gig, though, I couldn’t help notice how the enthusiastic roars from the crowd contrasted starkly with the sluggish retorts to calls for action.

While most of the acts chose songs vaguely fitting for the event, such as Duran Duran’s ‘Planet Earth’ and Snow Patrol’s ‘Open your eyes’, it seemed as though the rendition of that revolutionary rock anthem ‘Que sera sera, whatever will be, will be…” by David Gray and Damien Rice (though fantastic) summed up the indifferent feeling from the audience most aptly. As they say ‘recognition is the first step to recovery’. It’s going to take a lot more than a rock concert to change human behaviour, but the mainstream recognition of the problem signified by Live Earth suggests we are at least heading in the right direction.

Olive Heffernan
News Editor
Nature Reports Climate Change

Posted by Olive Heffernan on July 09, 2007
Categories: Communicating Climate Change, In the News, Olive Heffernan | Permalink | Comments (3) | TrackBacks (0)

Posted by Olive Heffernan on behalf of Roger Pielke Jnr.

Writing last week in The American Prospect, Peter Teague and Jeff Navin explain the complexities of U.S. public opinion on climate change and its implication for climate politics and policy:

Americans' anxiety over rising energy costs is a serious challenge to anyone seeking a solution to global warming. The anxiety is real, and the vast majority of Americans perceive these costs as causing financial hardship for their families. Proposals that raise energy prices risk triggering populist anger; Americans uniformly reject government efforts to increase the cost of gasoline or electricity as a way of encouraging certain kinds of behaviors.

Nobody disagrees that regulatory strategies alone will raise energy costs. And raising the price of carbon high enough to have a real effect on global warming -- by cutting emissions and by providing sufficient motivation for industry to invest in new technologies -- will raise energy costs significantly. . .

With a regulatory-only approach, we will end with a debate between environmentalists arguing about the cost of global warming, and industry economists telling Americans how much more they'll pay for everything from electricity to gasoline to consumer products. And they'll argue that these higher prices will result in job losses.

Policy makers are aware of this challenge and have added provisions to their regulatory bills that are aimed at easing voters' fears. There are proposals for tax rebates and offsets and even the creation of a "Climate Change Credit Corporation" to help voters with the anticipated increase in consumer energy costs. The trouble is that the bills either provide tiny amounts to authorize studies of the problem, or they remain silent about how much help voters can expect. It's important to remember that the proponents of [the failed California] Prop. 87 made a well-supported case that the initiative wouldn't raise energy costs at all. Its defeat demonstrates that it's going to take more than good intentions about global warming and vaguely-worded proposals to convince voters

Continue reading "Understanding the Politics of Climate Change in the United States" »

Posted by Olive Heffernan on July 03, 2007
Categories: Climate Policy, In the News, Roger Pielke, Jr | Permalink | Comments (2) | TrackBacks (0)