Tuesday, August 21, 2007

GLOBAL WARMING OR COOLING?

An email from Peter R Odell, Professor Emeritus of International Energy Studies, Erasmus University, Rotterdam

The UK's Metereological Office research centre has now had to confirm a fall in average global temperatures since 1998 (The Guardian, 10 August 2007, pp1/2). This clearly opens to challenge the widely-held view that it is primarily the growth in carbon dioxide emissions, released by mankind's use of carbon fuels, that cause global warming. Indeed, since 1998 there has been a record near-25% increase in the production and use of coal, oil and natural gas - totalling an additional 2000 million tons of oil equivalent over the nine year period. Two-fifths of this has been coal, the most polluting of the three carbon fuels, so generating voluminous additional carbon dioxide for the atmosphere.

Yet, in spite of an all-time peak period of carbon fuels' use, it seems that no overall global warming phenomenon has been generated! Thus, instead of the Met Office's think-tank apparent acceptance of the concept of a demonstrable relationship between global warming and carbon dioxide emissions for its future forecasts, should it not first be held responsible for an explanation as to why this has not happened over the past nine years - and why it will not happen for at least the next three years?




GREENIE CONFUSION

Compare and contrast the next two articles below. Is planting trees good or bad? It illustrates the knots that stupid assumptions can get you into

Forget biofuels - burn oil and plant forests instead

It sounds counterintuitive, but burning oil and planting forests to compensate is more environmentally friendly than burning biofuel. So say scientists who have calculated the difference in net emissions between using land to produce biofuel and the alternative: fuelling cars with gasoline and replanting forests on the land instead. They recommend governments steer away from biofuel and focus on reforestation and maximising the efficiency of fossil fuels instead.

The reason is that producing biofuel is not a "green process". It requires tractors and fertilisers and land, all of which means burning fossil fuels to make "green" fuel. In the case of bioethanol produced from corn - an alternative to oil - "it's essentially a zero-sums game," says Ghislaine Kieffer, programme manager for Latin America at the International Energy Agency in Paris, France (see Complete carbon footprint of biofuel - or is it?).

What is more, environmentalists have expressed concerns that the growing political backing that biofuel is enjoying will mean forests will be chopped down to make room for biofuel crops such as maize and sugarcane. "When you do this, you immediately release between 100 and 200 tonnes of carbon [per hectare]," says Renton Righelato of the World Land Trust, UK, a conservation agency that seeks to preserve rainforests.

Righelato and Dominick Spracklen of the University of Leeds, UK, calculated how long it would take to compensate for those initial emissions by burning biofuel instead of gasoline. The answer is between 50 and 100 years. "We cannot afford that, in terms of climate change," says Righelato.

The researchers also compared how much carbon would be stored by replanting forests with how much is saved by burning biofuel grown on the land instead of gasoline. They found that reforestation would sequester between two and nine times as much carbon over 30 years than would be saved by burning biofuels instead of gasoline (see bar chart, right). "You get far more carbon sequestered by planting forests than you avoid emissions by producing biofuels on the same land," says Righelato.

He and Spracklen conclude that if the point of biofuels policies is to limit global warming, "policy makers may be better advised in the short term to focus on increasing the efficiency of fossil fuel use, to conserve existing forests and savannahs, and to restore natural forest and grassland habitats on cropland that is not needed for food." They do admit, however, that biofuels made from woody materials such as prairie grasses may have an advantage over reforestation - although it is difficult to say for now as such fuels are still in development.

Forests at high latitudes have been found to sequester less carbon than tropical forests. But Righelato says this does not affect his calculations as biofuel crops are not, by and large, grown in these areas.

Source





Trees don't work as carbon offset

As millions of Britons jet off to foreign climes for their holiday this month, the more environmentally minded travellers will have salved their consciences by paying for trees to be planted to compensate for the carbon emissions caused by their flight.

But a ground-breaking study has now called into question the effectiveness of using trees to "offset" emissions, suggesting that their ability to "lock-up" carbon dioxide has been greatly exaggerated.

Forests have long been seen as an effective way of absorbing the greenhouse gases, such as carbon dioxide, which are thought to trap the sun's heat in the atmosphere, causing global warming. Celebrities, including the Rolling Stones and Leonardo DiCaprio, the film actor, have signed up to schemes to plant trees to offset their own emissions. However, the new research found that trees bathed in extra carbon dioxide grew more tissue, but did not necessarily store significant extra quantities of carbon. Instead, the tree's capacity to absorb the gas depended on water and nutrient levels.

The news will come as a blow to the carbon-offsetting industry, which has expanded rapidly as individuals and companies try to atone for their carbon dioxide emissions by paying companies to plant trees for them.....

According to the Department for Environment, Food and Rural Affairs, Britons spent 60 million pounds on such schemes last year. This is forecast to grow to 250 million annually by 2009.

The latest findings come from an ongoing study - known as the Free Air Carbon Enrichment project - which has been running for 13 years at Duke University, North Carolina, in the US. Researchers bathed plots of pine trees in extra carbon dioxide every day for 10 years and found that while the trees grew more tissue, only those that received the most water and nutrients stored enough carbon dioxide to offset the effects of global warming.

Ram Oren, the ecologist who led the project, said the research suggested that planting more trees would not be successful in slowing the pace of climate change. "More trees don't necessarily mean less carbon dioxide," he said. "Planting trees is not going to do a whole lot to decreasing carbon concentration. "What we're finding is that extra carbon very quickly goes back into the atmosphere if there are low nutrients and water available.

Source







STATISTICS AND CLIMATOLOGY: GAMBLING ON TOMORROW

Modelling the Earth's climate mathematically is hard already. Now a new difficulty is emerging

When the Royal Society, the world's oldest academy of the discipline, was founded in London in 1660, the subject was referred to as natural philosophy. In the 19th century, though, nature and philosophy went their separate ways as the natural philosophers grew in number, power and influence. Nevertheless, the link between the fields lingers on in the name of one of the Royal Society's journals, Philosophical Transactions. And appropriately, the latest edition of that publication, which is devoted to the science of climate modelling, is in part a discussion of the understanding and misunderstanding of the ideas of one particular 18th-century English philosopher, Thomas Bayes.

Bayes was one of two main influences on the early development of probability theory and statistics. The other was Blaise Pascal, a Frenchman. But, whereas Pascal's ideas are simple and widely understood, Bayes's have always been harder to grasp. Pascal's way of looking at the world was that of the gambler: each throw of the dice is independent of the previous one. Bayes's allows for the accumulation of experience, and its incorporation into a statistical model in the form of prior assumptions that can vary with circumstances. A good prior assumption about tomorrow's weather, for example, is that it will be similar to today's. Assumptions about the weather the day after tomorrow, though, will be modified by what actually happens tomorrow.

Psychologically, people tend to be Bayesians to the extent of often making false connections. And that risk of false connection is why scientists like Pascal's version of the world. It appears to be objective. But when models are built, it is almost impossible to avoid including Bayesian-style prior assumptions in them. By failing to acknowledge that, model builders risk making serious mistakes.

In one sense it is obvious that assumptions will affect outcomes -- another reason Bayes is not properly acknowledged. That obviousness, though, buries deeper subtleties. In one of the papers in Philosophical Transactions David Stainforth of Oxford University points out a pertinent example. Climate models have lots of parameters that are represented by numbers -- for example, how quickly snow crystals fall from clouds, or for how long they reside within those clouds. Actually, these are two different ways of measuring the same thing, so whether a model uses one or the other should make no difference to its predictions. And, on a single run, it does not.

But models are not given single runs. Since the future is uncertain, they are run thousands of times, with different values for the parameters, to produce a range of possible outcomes. The outcomes are assumed to cluster around the most probable version of the future. The particular range of values chosen for a parameter is an example of a Bayesian prior assumption, since it is derived from actual experience of how the climate behaves -- and may thus be modified in the light of experience.

But the way you pick the individual values to plug into the model can cause trouble. They might, for example, be assumed to be evenly spaced, say 1,2,3,4. But in the example of snow retention, evenly spacing both rate-of-fall and rate-of-residence-in-the-clouds values will give different distributions of result. That is because the second parameter is actually the reciprocal of the first. To make the two match, value for value, you would need, in the second case, to count 1, 1/2, 1/4 which is not evenly spaced. If you use evenly spaced values instead, the two models' outcomes will cluster differently.

Climate models have hundreds of parameters that might somehow be related in this sort of way. To be sure you are seeing valid results rather than artefacts of the models, you need to take account of all the ways that can happen. That logistical nightmare is only now being addressed, and its practical consequences have yet to be worked out. But because of their philosophical training in the rigours of Pascal's method, the Bayesian bolt-on does not come easily to scientists. As the old saw has it, garbage in, garbage out. The difficulty comes when you do not know what garbage looks like.

Source






Just When You Thought the `Green' Movement Couldn't Get Any Weirder

Post below lifted from Newsbusters.

Matt Damon dressed as gas pump? Ben Affleck as an ear of corn? No, it's not "Good Will Hunting," the sequel. It's a new set of videos promoting ethanol mandates on the Web site cleanmyride.org.

The Clean My Ride site is run by the Center for American Progress Action Fund, an arm of the liberal think tank Center for American Progress. The purpose of Clean My Ride is to urge Congress to mandate ethanol as a fuel.


Earlier this week, NBC's Lee Cowan admitted it was ethanol's fault milk prices were "skyrocketing." So which is it? Do environmentalists want better gas mileage or cheaper milk?


One of the other main points of the Web site is to try and get people to stop "running scared from Big Oil." The first video, which features Affleck in a corn costume - it's better than "Gigli" - even shows a sequence where "Big Oil" executives are chasing down an ear of corn and then bludgeoning it to death.


The site encourages visitors to send this message to Congress (emphasis added):


Dear Representative:America must increase its energy independence and stop global warming. To accomplish these goals, I strongly urge you to vote for provisions that require cars and light trucks get 35 miles per gallon by 2020, and to require some service stations sell ethanol for flexible fuel cars. These two measures will reduce oil use, save families money, and lower global warming pollution. Please support them as essential parts of energy legislation.

The site also features six videos following the main character "Phin" who does whatever he can to try and convince people to help him on "his quest to save the environment."


Other videos feature celebrities Sarah Silverman, Jason Biggs, Joshua Jackson and Jennifer Garner.


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The Lockwood paper was designed to rebut Durkin's "Great Global Warming Swindle" film. It is a rather confused paper -- acknowleging yet failing to account fully for the damping effect of the oceans, for instance -- but it is nonetheless valuable to climate atheists. The concession from a Greenie source that fluctuations in the output of the sun have driven climate change for all but the last 20 years (See the first sentence of the paper) really is invaluable. And the basic fact presented in the paper -- that solar output has in general been on the downturn in recent years -- is also amusing to see. Surely even a crazed Greenie mind must see that the sun's influence has not stopped and that reduced solar output will soon start COOLING the earth! Unprecedented July 2007 cold weather throughout the Southern hemisphere might even be the first sign that the cooling is happening. And the fact that warming plateaued in 1998 is also a good sign that we are moving into a cooling phase. As is so often the case, the Greenies have got the danger exactly backwards. See my post of 7.14.07 and a very detailed critique here for more on the Lockwood paper

For more postings from me, see TONGUE-TIED, EDUCATION WATCH INTERNATIONAL, POLITICAL CORRECTNESS WATCH, FOOD & HEALTH SKEPTIC, GUN WATCH, SOCIALIZED MEDICINE, AUSTRALIAN POLITICS, DISSECTING LEFTISM, IMMIGRATION WATCH INTERNATIONAL and EYE ON BRITAIN. My Home Pages are here or here or here. Email me (John Ray) here. For times when blogger.com is playing up, there are mirrors of this site here and here.

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