Tim Blair professes not to give a damn about global warming but also reckons it a scam and has over twenty rather confused posts in just the last month attacking the concept. In his latest post he seems to think that only the Arctic is warming, quoting John Christy.
"It just doesn't look like global warming is very global," said John Christy, director of UAH's Earth System Science Center.
"The carbon dioxide from fossil fuels is distributed pretty evenly around the globe and not concentrated in the Arctic, so it doesn't look like we can blame greenhouse gases for the overwhelming bulk of the Northern Hemisphere warming over the past 27 years" he said. "The most likely suspect for that is a natural climate change or cycle that we didn't expect or just don't understand."
Christy, of course, spent years denying that global warming was happening because of his analysis of satellite data that showed no warming. Eventually it was discovered that he'd made a mistake and the satellites did show warming. It seems he's now retreated to the next line of defence for Global Warming skeptics---claiming that the observed warming is natural.
Is the warming just confined to the Arctic? Study the image below, which shows the warming (or cooling) rate for the lower troposphere from satellite measurements:
The warming isn't just in the Arctic---it includes almost every spot on the globe. And yes, the warming is more pronounced in the Arctic. Does that prove that carbon dioxide isn't doing it? Well, no. It was predicted that Arctic would warm more from increased CO2:
The Arctic had been predicted to be hit first by global warming, principally because warming at the northern pole is enhanced by positive feedback.
Snow and ice reflect 80% to 90% of solar radiation back into space. But when these white surfaces disappear, more solar radiation is absorbed by the underlying land or sea as heat. This heat, in turn, melts more snow and ice.
Another reason for the Arctic's sensitivity is that the air there is extremely dry compared to air at lower latitudes, says Prestrud. This means that less energy is used up in evaporating water, leaving more as heat.
I reckon Christy will be retreating to the third defence line soon (if I recall correctly, that's "Warming will be beneficial").
Just six days ago, Cecilia Bitz of the University of Washington posted an excellent discussion of polar amplification at RealClimate.
And RoyBoy has retreated to occasionally scribing fundie Christian tripe. Does the brain react like this when one makes a huge f-up that persisted for years?
As I understand it S+C still include the Antarctic (70oS and below) in their numbers. RSS does not, as the graphic illustrates, saying that because of the high altitude of the Antarctic plateau S+C are essentially including surface measurements. As Dano notes, S is pretty well out of the closet on the Christian fundamentalist bit, having among other things written an article on Tech Central Station defending ID. C hasn't gone that far, but a look at his CV shows that he was a Baptist missionary in Africa before going into the climatology biz, and appears to remain active in his church. Draw your own conclusions from that. One conclusion I draw is that C is preparing to attack the AR4 frontally as soon as it comes out next year, and so has ceased being worried about burning bridges with the rest of the climatological community.
"As I understand it S+C still include the Antarctic (70oS and below) in their numbers. RSS does not, as the graphic illustrates, saying that because of the high altitude of the Antarctic plateau S+C are essentially including surface measurements. "
Actually, neither team does--at least, not most of it. The orbital path of the TIROS-N and ATN series of satellites that carry the MSU packages traverse the polar regions along pretty much zonal (latitude direction) paths that pick up the Antarctic rim, but not the poles themselves. The trends of the two teams are also qualitatively different (at least in this context). The corrected S+C record is the lower troposphere TLT product that uses combinations of side-looking and nadir views to extract a direct measurement that will be closer to the surface. RSS uses direct Channel 2 data that captures the middle troposphere rather than the lower, so the RSS records and S+C's corrected record that's getting so much attention, aren't equivalent (the S+C product that's most comparable to RSS is their TMT product). You're right that S+C's TLT will get more surface in their measurements than RSS. But the impact of this near the poles (particularly the Antarctic), large or small, is more likely to be due to variations in the surface albedo from annual and/or interannual variations in sea-ice and melt pools than altitude alone. All the best.
"I reckon Christy will be retreating to the third defence line soon (if I recall correctly, that's "Warming will be beneficial")"
What do we think of these candidates for the fourth, fifth, sixth and seventh defence lines?
"4. The costs of policies to stop warming will be worse than the consequences of warming."
"5. The huge costs of current GHG reduction policies aren't worth the small reduction of warming they will achieve.
"6. Warming isn't as big a problem as others like lack of water and sanitation in developing countries which we can fix more cheaply."
"7. Why should Australia/US/whoever adopt warming policies which will harm our national interests when any GHG reductions will be wiped out by growth in China?"
Shouldn't there be some warming over the antarctic? Isn't this the place where an increased greenhouse effect due to increased CO2 concentrations would be most apparent?
Regarding #5, position 6 already is Christy's position. (As quoted in a magazine profile, probably Discover).
That position - call it the Lomborg gambit - would have more credibility if the majority of its adherents actively promoted devoting more resources to addressing those other problems.
In practice, as right-wing free-marketers they probably adhere to the global version of trickle-down theory.