This article contains some very interesting backgound on the debate about climate change. You can click on the link in the title for more information. Lots of stuff in the body of the article that is not posted here. Worth checking out.
By Sharon Begley
Newsweek
Aug. 13, 2007 issue - Sen. Barbara Boxer had been chair of the Senate's Environment Committee for less than a month when the verdict landed last February. "Warming of the climate system is unequivocal," concluded a report by 600 scientists from governments, academia, green groups and businesses in 40 countries. Worse, there was now at least a 90 percent likelihood that the release of greenhouse gases from the burning of fossil fuels is causing longer droughts, more flood-causing downpours and worse heat waves, way up from earlier studies. Those who doubt the reality of human-caused climate change have spent decades disputing that. But Boxer figured that with "the overwhelming science out there, the deniers' days were numbered." As she left a meeting with the head of the international climate panel, however, a staffer had some news for her. A conservative think tank long funded by ExxonMobil, she told Boxer, had offered scientists $10,000 to write articles undercutting the new report and the computer-based climate models it is based on. "I realized," says Boxer, "there was a movement behind this that just wasn't giving up."
f you think those who have long challenged the mainstream scientific findings about global warming recognize that the game is over, think again. Yes, 19 million people watched the "Live Earth" concerts last month, titans of corporate America are calling for laws mandating greenhouse cuts, "green" magazines fill newsstands, and the film based on Al Gore's best-selling book, "An Inconvenient Truth," won an Oscar. But outside Hollywood, Manhattan and other habitats of the chattering classes, the denial machine is running at full throttle—and continuing to shape both government policy and public opinion.
Since the late 1980s, this well-coordinated, well-funded campaign by contrarian scientists, free-market think tanks and industry has created a paralyzing fog of doubt around climate change. Through advertisements, op-eds, lobbying and media attention, greenhouse doubters (they hate being called deniers) argued first that the world is not warming; measurements indicating otherwise are flawed, they said. Then they claimed that any warming is natural, not caused by human activities. Now they contend that the looming warming will be minuscule and harmless. "They patterned what they did after the tobacco industry," says former senator Tim Wirth, who spearheaded environmental issues as an under secretary of State in the Clinton administration. "Both figured, sow enough doubt, call the science uncertain and in dispute. That's had a huge impact on both the public and Congress."
Just last year, polls found that 64 percent of Americans thought there was "a lot" of scientific disagreement on climate change; only one third thought planetary warming was "mainly caused by things people do." In contrast, majorities in Europe and Japan recognize a broad consensus among climate experts that greenhouse gases—mostly from the burning of coal, oil and natural gas to power the world's economies—are altering climate. A new NEWSWEEK Poll finds that the influence of the denial machine remains strong. Although the figure is less than in earlier polls, 39 percent of those asked say there is "a lot of disagreement among climate scientists" on the basic question of whether the planet is warming; 42 percent say there is a lot of disagreement that human activities are a major cause of global warming. Only 46 percent say the greenhouse effect is being felt today.
As a result of the undermining of the science, all the recent talk about addressing climate change has produced little in the way of actual action. Yes, last September Gov. Arnold Schwarzenegger signed a landmark law committing California to reduce statewide emissions of carbon dioxide to 1990 levels by 2020 and 80 percent more by 2050. And this year both Minnesota and New Jersey passed laws requiring their states to reduce greenhouse emissions 80 percent below recent levels by 2050. In January, nine leading corporations—including Alcoa, Caterpillar, Duke Energy, Du Pont and General Electric—called on Congress to "enact strong national legislation" to reduce greenhouse gases. But although at least eight bills to require reductions in greenhouse gases have been introduced in Congress, their fate is decidedly murky. The Democratic leadership in the House of Representatives decided last week not even to bring to a vote a requirement that automakers improve vehicle mileage, an obvious step toward reducing greenhouse emissions. Nor has there been much public pressure to do so. Instead, every time the scientific case got stronger, "the American public yawned and bought bigger cars," Rep. Rush Holt, a New Jersey congressman and physicist, recently wrote in the journal Science; politicians "shrugged, said there is too much doubt among scientists, and did nothing."
It was 98 degrees in Washington on Thursday, June 23, 1988, and climate change was bursting into public consciousness. The Amazon was burning, wildfires raged in the United States, crops in the Midwest were scorched and it was shaping up to be the hottest year on record worldwide. A Senate committee, including Gore, had invited NASA climatologist James Hansen to testify about the greenhouse effect, and the members were not above a little stagecraft. The night before, staffers had opened windows in the hearing room. When Hansen began his testimony, the air conditioning was struggling, and sweat dotted his brow. It was the perfect image for the revelation to come. He was 99 percent sure, Hansen told the panel, that "the greenhouse effect has been detected, and it is changing our climate now."
The reaction from industries most responsible for greenhouse emissions was immediate. "As soon as the scientific community began to come together on the science of climate change, the pushback began," says historian Naomi Oreskes of the University of California, San Diego. Individual companies and industry associations—representing petroleum, steel, autos and utilities, for instance—formed lobbying groups with names like the Global Climate Coalition and the Information Council on the Environment. ICE's game plan called for enlisting greenhouse doubters to "reposition global warming as theory rather than fact," and to sow doubt about climate research just as cigarette makers had about smoking research. ICE ads asked, "If the earth is getting warmer, why is Minneapolis [or Kentucky, or some other site] getting colder?" This sounded what would become a recurring theme for naysayers: that global temperature data are flat-out wrong. For one thing, they argued, the data reflect urbanization (many temperature stations are in or near cities), not true global warming.
Shaping public opinion was only one goal of the industry groups, for soon after Hansen's sweat-drenched testimony they faced a more tangible threat: international proposals to address global warming. The United Nations had scheduled an "Earth Summit" for 1992 in Rio de Janeiro, and climate change was high on an agenda that included saving endangered species and rain forests. ICE and the Global Climate Coalition lobbied hard against a global treaty to curb greenhouse gases, and were joined by a central cog in the denial machine: the George C. Marshall Institute, a conservative think tank. Barely two months before Rio, it released a study concluding that models of the greenhouse effect had "substantially exaggerated its importance." The small amount of global warming that might be occurring, it argued, actually reflected a simple fact: the Sun is putting out more energy. The idea of a "variable Sun" has remained a constant in the naysayers' arsenal to this day, even though the tiny increase in solar output over recent decades falls far short of explaining the extent or details of the observed warming.
In what would become a key tactic of the denial machine—think tanks linking up with like-minded, contrarian researchers—the report was endorsed in a letter to President George H.W. Bush by MIT meteorologist Richard Lindzen. Lindzen, whose parents had fled Hitler's Germany, is described by old friends as the kind of man who, if you're in the minority, opts to be with you. "I thought it was important to make it clear that the science was at an early and primitive stage and that there was little basis for consensus and much reason for skepticism," he told Scientific American magazine. "I did feel a moral obligation."
Bush was torn. The head of his Environmental Protection Agency, William Reilly, supported binding cuts in greenhouse emissions. Political advisers insisted on nothing more than voluntary cuts. Bush's chief of staff, John Sununu, had a Ph.D. in engineering from MIT and "knew computers," recalls Reilly. Sununu frequently logged on to a computer model of climate, Reilly says, and "vigorously critiqued" its assumptions and projections.
Sununu's side won. The Rio treaty called for countries to voluntarily stabilize their greenhouse emissions by returning them to 1990 levels by 2000. (As it turned out, U.S. emissions in 2000 were 14 percent higher than in 1990.) Avoiding mandatory cuts was a huge victory for industry. But Rio was also a setback for climate contrarians, says UCSD's Oreskes: "It was one thing when Al Gore said there's global warming, but quite another when George Bush signed a convention saying so." And the doubters faced a newly powerful nemesis. Just months after he signed the Rio pact, Bush lost to Bill Clinton—whose vice president, Gore, had made climate change his signature issue.
Groups that opposed greenhouse curbs ramped up. They "settled on the 'science isn't there' argument because they didn't believe they'd be able to convince the public to do nothing if climate change were real," says David Goldston, who served as Republican chief of staff for the House of Representatives science committee until 2006. Industry found a friend in Patrick Michaels, a climatologist at the University of Virginia who keeps a small farm where he raises prize-winning pumpkins and whose favorite weather, he once told a reporter, is "anything severe." Michaels had written several popular articles on climate change, including an op-ed in The Washington Post in 1989 warning of "apocalyptic environmentalism," which he called "the most popular new religion to come along since Marxism." The coal industry's Western Fuels Association paid Michaels to produce a newsletter called World Climate Report, which has regularly trashed mainstream climate science. (At a 1995 hearing in Minnesota on coal-fired power plants, Michaels admitted that he received more than $165,000 from industry; he now declines to comment on his industry funding, asking, "What is this, a hatchet job?")
The road from Rio led to an international meeting in Kyoto, Japan, where more than 100 nations would negotiate a treaty on making Rio's voluntary—and largely ignored—greenhouse curbs mandatory. The coal and oil industries, worried that Kyoto could lead to binding greenhouse cuts that would imperil their profits, ramped up their message that there was too much scientific uncertainty to justify any such cuts. There was just one little problem. The Intergovernmental Panel on Climate Change, or IPCC—the international body that periodically assesses climate research—had just issued its second report, and the conclusion of its 2,500 scientists looked devastating for greenhouse doubters. Although both natural swings and changes in the Sun's output might be contributing to climate change, it concluded, "the balance of evidence suggests a discernible human influence on climate."
more on the newsweek site....
2 comments:
AGW is a joke?
PDF file with lots of graphs and >0.50 correlation at 0.99 signiicanse level on what controls climate. VERY INTERRESTING!
PDF with physicists that claims heat can't move from the cold atmosphere to warm earth surface and thus no greenhouse effect!
/Magnus Andersson
interesting reading for sure.
I thought you might be interested in these two articles as well:
Statistics and climatology
Gambling on tomorrow
Aug 16th 2007
From The Economist print edition
http://www.economist.com/science/displaystory.cfm?story_id=9645336
Modelling the Earth's climate mathematically is hard already. Now a new difficulty is emerging
“SCIENCE” is a recently coined word. 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 Bayesian—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.
Assume nothing
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, ½, ⅓, ¼—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.
Modelling the climate
Tomorrow and tomorrow
Aug 16th 2007
From The Economist print edition
http://www.economist.com/science/displaystory.cfm?story_id=9645109
A group of climatologists discover reality
WHILE some argue about the finer philosophical points of how to improve models of the climate (see article), others just get on with it. Doug Smith and his colleagues at the Hadley Centre, in Exeter, England, are in the second camp and they seem to have stumbled on to what seems, in retrospect, a surprisingly obvious way of doing so. This is to start the model from observed reality.
Until now, when climate modellers began to run one of their models on a computer, they would “seed” it by feeding in a plausible, but invented, set of values for its parameters. Which sets of invented parameter-values to use is a matter of debate. But Dr Smith thought it might not be a bad idea to start, for a change, with sets that had really happened. He therefore gave his models a series of decade-long tests beginning with the real climatic conditions (level of solar radiation, ocean temperature and so on) on 80 different start dates from 1982 to 2001.
As he reported recently in Science, the use of such real starting data made a huge improvement to the accuracy of the results. It reproduced what had happened over the courses of the decades in question as much as 50% more accurately than the results of runs based on arbitrary starting conditions.
Hindcasting, as this technique is known, is a recognised way of testing models. The proof of the pudding, though, is in the forecasting, so Dr Smith plugged in the data from two ten-day periods in 2005 (one in March and one in June), pressed the start button and crossed his fingers.
The results suggested that the world would cool from February this year until 2009. After that, it will start warming up again, with at least half of the years between 2010 and 2014 being warmer than 1998, the hottest on record so far.
Given the rainy British summer this year, the view from north-west Europe is that the new way of doing things is spot on. Shame it took so long to think of it.
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