Plimer actually has done the “debate” a great service; he has assembled all the contrarian arguments in one place and demonstrated that they are a load of, choose your own metaphor. I’ve spent a bit of time recently looking at contrarian arguments they invariably contain fundamental errors in basic maths or physics or, intentionally or otherwise, misreperesent the data that they are quoting. The Speccie’s discussions on this subject are particularly risible.

“I’ve spent a bit of time recently looking at contrarian arguments they invariably contain fundamental errors in basic maths or physics or, intentionally or otherwise, misreperesent the data that they are quoting.”

You mean like extrapolating data to predict the behaviour of variables outside the observed range ? Something that a GCSE chemistry student would be expected to know was a bollocks methodology ?
Like for example, claiming a causal relationship, between 2 variables which have existed for millions of years, based on data from the minutest fraction of that period ?

Yes, contrarian arguments like that MM.

It is pointless arguing with warmist ideologues.

Shorter Matt Munro: there is no basic, well-understood physics underlying radiative transfer, it’s all derived from dodgy statistical analysis. La La La, I can’t hear you!

Good grief man, are you really that ignorant? Surely even a GSCE physics student would be expected to know a little about basic thermodynamics, the black-body radiation curve, and the existence of absorption lines?

World’s climate could cool first, warm later

17:56 04 September 2009 by Fred Pearce, Geneva,The New Scientist
For similar stories, visit the Climate Change Topic Guide
Forecasts of climate change are about to go seriously out of kilter. One of the world’s top climate modellers said Thursday we could be about to enter one or even two decades during which temperatures cool.

“People will say this is global warming disappearing,” he told more than 1500 of the world’s top climate scientists gathering in Geneva at the UN’s World Climate Conference.

“I am not one of the sceptics,” insisted Mojib Latif of the Leibniz Institute of Marine Sciences at Kiel University, Germany. “However, we have to ask the nasty questions ourselves or other people will do it.”

Few climate scientists go as far as Latif, an author for the Intergovernmental Panel on Climate Change. But more and more agree that the short-term prognosis for climate change is much less certain than once thought.

Nature vs humans

This is bad timing. The UN’s World Meteorological Organization called the conference in order to draft a global plan for providing “climate services” to the world: that is, to deliver climate predictions useful to everyone from farmers worried about the next rainy season to doctors trying to predict malaria epidemics and builders of dams, roads and other infrastructure who need to assess the risk of floods and droughts 30 years hence.

But some of the climate scientists gathered in Geneva to discuss how this might be done admitted that, on such timescales, natural variability is at least as important as the long-term climate changes from global warming. “In many ways we know more about what will happen in the 2050s than next year,” saidVicky Pope from the UK Met Office.

Cold Atlantic

Latif predicted that in the next few years a natural cooling trend would dominate over warming caused by humans. The cooling would be down to cyclical changes to ocean currents and temperatures in the North Atlantic, a feature known as the North Atlantic Oscillation (NAO).

Breaking with climate-change orthodoxy, he said NAO cycles were probably responsible for some of the strong global warming seen in the past three decades. “But how much? The jury is still out,” he told the conference. The NAO is now moving into a colder phase.

Latif said NAO cycles also explained the recent recovery of the Sahel region of Africa from the droughts of the 1970s and 1980s. James Murphy, head of climate prediction at the Met Office, agreed and linked the NAO to Indian monsoons, Atlantic hurricanes and sea ice in the Arctic. “The oceans are key to decadal natural variability,” he said.

Another favourite climate nostrum was upturned when Pope warned that thedramatic Arctic ice loss in recent summers was partly a product of natural cycles rather than global warming. Preliminary reports suggest there has been much less melting this year than in 2007 or 2008.

In candid mood, climate scientists avoided blaming nature for their faltering predictions, however. “Model biases are also still a serious problem. We have a long way to go to get them right. They are hurting our forecasts,” said Tim Stockdale of the European Centre for Medium-Range Weather Forecasts in Reading, UK.

The world may badly want reliable forecasts of future climate. But such predictions are proving as elusive as the perfect weather forecast.

But this is where the Greens purposely try to confuse the public. They confuse normal global warming with anthropogenic global warming. The melting of the Arctic ice is just more evidence of climate change, not evidence that humans are the cause. Arctic melting is a continuance of the same global warming which began 20,000 years ago, which was the end of a global cooling period which was about 80,000 years long, which was the end of a global warming period which was about 30,000 years long. etc. etc. etc. Attributing arctic melt to human activity is impossible to support scientifically. This kind of purposeful confusion is doing tremendous damage to the environmental movement, and the public does not believe anything the Greens say anymore. Nice work.

To say that Plimer’s argument is “simply wrong” is grossly misleading. The measures that have been used for years are area and extent. You can’t just switch to a new measure and declare that he’s simply wrong. A volume record going back only to 2004 is not long enough to tell you anything meaningful about anything.

At the risk of being slightly unhelpful, when it’s alleged that “the greens” (or whoever you like) are intentionally trying to mislead the public, perpetrating some hoax, et cetera — what’s supposed to be in it for them?

I’m not sure that’s quite right. I don’t think (most) greens are trying to mislead the public – they hear what the scientists say and they run with it. But out of the AGW scare, they get a world the works the way they would like to see it run – less consumption, less freedom, fewer people and so on.

The climate bureaucracy and some of the scientists may well be guilty of misleading the public though. They of course have a direct pecuniary interest.

To say that Plimer’s argument is “simply wrong” is grossly misleading. The measures that have been used for years are area and extent. You can’t just switch to a new measure and declare that he’s simply wrong.

He’s “simply wrong” on extent too.

http://www.dailytech.com/Sea+Ice+Ends+Year+at+Same+Level+as+1979/article13834.htm

“Sea Ice Ends Year at Same Level as 1979

Rapid growth spurt leaves amount of ice at levels seen 29 years ago.”

Thanks to a rapid rebound in recent months, global sea ice levels now equal those seen 29 years ago, when the year 1979 also drew to a close.

Ice levels had been tracking lower throughout much of 2008, but rapidly recovered in the last quarter. In fact, the rate of increase from September onward is the fastest rate of change on record, either upwards or downwards.

The data is being reported by the University of Illinois’s Arctic Climate Research Center, and is derived from satellite observations of the Northern and Southern hemisphere polar regions. “

http://www.guardian.co.uk/environment/georgemonbiot/2009/may/15/climate-change-scepticism-arctic-ice

Quote from leading climate change alarmist George Monbiot of the Guardian after trying to ridicule Christopher Booker’s claims on Arctic ice in an earlier article…..

“Whoops ? looks like I’ve boobed. Sorry folks. As one of the posters on this thread points out, there are in fact two averages in play ? 1979-2000 and 1979-2009. It is therefore correct to state that the April 2009 extent exceeds the 1979-2009 average, but not the 1979-2000 average. It remains the case, however, that the data relate to April, not May. Please accept my apologies for my mistake and the confusion it has caused.

Thanks to a rapid rebound in recent months, global sea ice levels now equal those seen 29 years ago, when the year 1979 also drew to a close.

Sure, you can find one or two datapoints in the series which equal or exceed earlier datapoints, but that doesn’t tell you anything about the trend. You don’t determine a trend by picking two favourable points and drawing a line between them, unless you’re statistically illiterate. Plus, your Daily Tech link is talking about global sea ice (which is still declining, despite the fact that they’ve compressed the anomaly graph so much that it’s difficult to see), while Pilmer was referring to Arctic sea ice.

Dunc

I agree with your points about short term trends – that’s why the ice volume figures are irrelevant at present. It’s also worthwhile pointing out however that it is equally cherrypicking to discuss only the Arctic sea ice. The global figure is surely the only one that is relevant (the Antarctic is above its long-term trend – strange this global warming thingy).

Plimer is is factually correct to say that the sea ice is growing – it has gone up from its (non-climatic) lows in 2007. Whether this means anything is another question. However, eyeballing the Cryosphere graph (the original is here http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/global.daily.ice.area.withtrend.jpg ) if you took out the 2007 ‘funny’ I don’t think you would see any significant trend at all.

Plimer is is factually correct to say that the sea ice is growing

That’s not what he said – he said that Arctic sea ice is growing. Would you accept such blatant equivocation between “global” and “Arctic” from someone (say, James Hansen) arguing in favour of AGW? I think not.

It’s also worthwhile pointing out however that it is equally cherrypicking to discuss only the Arctic sea ice. The global figure is surely the only one that is relevant (the Antarctic is above its long-term trend – strange this global warming thingy).

There are significant confounding factors when it comes to Antarctic sea ice, particularly ENSO, AAO, and variation in the location of the boundary of the Antarctic Circumpolar Current (see, for example, Interpretation of recent Antarctic sea ice variability, J Liu, JA Curry, DG Martinson – Geophys. Res. Lett, 2004 [PDF]). However, “[t]he observed hemispheric asymmetry in these trends is consistent with a modeled response to a carbon dioxide-induced climate warming.” Increased snowfall in the Antarctic under CO2 forcing is predicted by all models. It’s not intuitive – that’s why we need to do science.

However, eyeballing the Cryosphere graph … if you took out the 2007 ‘funny’ I don’t think you would see any significant trend at all.

“Eyeballing” is not a valid statistical analysis technique, and you don’t get to arbitrarily exclude datapoints just because you don’t like the look of them. You want to talk about significance, give me an R^2 value.

But the Arctic sea ice minimum this year is going to be higher in 2009 than in 2008 which was in turn higher than 2007. So, as I say he is factually correct, but as you rightly point out, whether this is significant is another matter because of the short time scales and it’s only one of the two poles.

You say there are significant confounding factors when it comes to the Antarctic. We know there are similar confounding factors in the Arctic too, as demonstrated by what happened in 2007. Which brings us back to global metrics and long-term trends.

Re measuring the impact of 2007 on the Arctic. Yes, you are right we cannot eyeball it. But we can’t say one way or the other without measuring it can we? Anyone know if the impact has been measured?

Historian of science, Naomi Oreskes of UC San Diego, states: “Scientific knowledge is the intellectual and social consensus of affiliated experts based on the weight of available empirical evidence, and evaluated according to accepted methodologies. If we feel that a policy question deserves to be informed by scientific knowledge, then we have no choice but to ask, what is the consensus of experts on this matter.”

Climate change has been extensively researched and the overwhelming majority of climate scientists agree that the observed modern day global warming is unprecedented and is very likely caused by humans. Although there is strong consensus among climate experts, many in the general public still think that these scientists are unsure about climate change and the role that humans have played in modern day global warming. The real science is primarily represented in peer-reviewed science journals. Science journals are typically not accessible to the general public and are also highly mathematical. Global warming misinformation is primarily published on Web pages, blogs, television shows, radio, and other forms of mass media, all of which are much more accessible to the general public than scientific journals. The result is that the misinformation is reaching more people than the real science. This Website tries to bridge the knowledge gap by summarizing some of the key research that has led scientists to their overwhelming consensus while also addressing some of the unfounded claims by climate change denialists.

http://www2.sunysuffolk.edu/mandias/global_warming/