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The problem is that the hypothesis of CO2 driven global warming asserts that temperature differentials will shrink, and the hypothesis of shrinking temperature differentials asserts that weather events will become more mild. You get to have one, or the other, not both. If you *do* have both, something is either wrong with your observation *or* something is wrong with the hypothesis.

Ah, I see what you are saying. You should also consider the impact of greater water vapour in the atmosphere and greater heat content in the ocean.

Over the past 100 years, we've had decades of warming, and decades of cooling, all during rises of CO2.

Not to mention, contrarians don't have to predict falling temperatures, all they need to do is predict *not* rising temperatures (which we've seen for the past 15 years).

There are certainly factors other than CO2 that need to be considered. Volcanoes will cause a dip in temperatures, El Nino a spike, La Nina a dip, increased solar activity a spike, decreased a dip, etc. The trend is being driven by CO2 and that trend is accelerating. It is hard to reconcile the idea that temperatures haven't been rising over the last 15 years and the fact that last year was hottest on record and last decade was hottest on record. Here is a graph of the temperature over the last 100 years with a 10 year running mean: http://www.woodfortrees.org/plot/gistemp/from:1911/to:2011/mean:120

So this brings to mind two questions - 1) why isn't it possible that the "hottest decade on record" isn't due to natural variability, and 2) if the record for the hottest year isn't broken within the next three years, will you assume your hypothesis has been falsified, or is this a rhetorical prediction?

1) What is meant by natural variability? Solar output is down. We are not in a period of the Milenkovic cycle that should cause (additional) warming. We know the forcing for CO2 and we know that there are more greenhouse gasses now than last decade. What natural variability are you referring to?

2) If the record isn't broken within the next three years then I would want to understand why not.

I wasn't claiming that the Earth's temperatures were or were not warmer -- I was referring to the fact that Steig 2009 finds substantial warming in Antarctica as an artifact of poor methodology.

Forgive my misunderstanding. I'm still not sure that you are right. O'Donnell finds some cooling areas between 1981-2006, but overall finds a slight warming trend. Both papers find a cooling trend between 1969-2000. Both find a warming trend between 1957-1981.

I see that you favour the idea that solar irradience is responsible for the current warming. You can compare temperature to solar output here: http://www.woodfortrees.org/plot/gistemp/mean:12/plot/sidc-ssn/mean:132/scale:0.01/from:1875/offset:-0.6/plot/esrl-co2/from:1875/scale:0.010/offset:-3.2 I've included CO2 on the graph as well. It doesn't seem like there is a clear corelation between solar output and temperatures (In fact it looks like they are headed in opposite directions). It is also interesting to note that solar output is highest during the period when both papers found Antarctic cooling (1969-2000). You considered a discrepancy between CO2 and Antarctic temperatures a nail in the AGW coffin. Does the same apply to the discrepancy between solar output and antarctic temperatures? More likely there is something else going on. Perhaps this is in part attributable to recent trends in the Southern Annular Mode (SAM)

Bear in mind that anthropogenic CO_2 over this interval looks nothing like this and is absurdly decorrelated from global temperature across the entire range except the last 150 years, right there in that confounding pesky solar activity grand maximum.

One thing that you should keep in mind is that there are multiple forcings. Solar activity is one of them. CO2 did not change much over the last 1000 years except in the last 150. Therefor CO2 was not a forcing until recently. You should not expect to see a corelation between temperature and CO2 over the last 100 years until recently.

Indeed, the keepers of the global climate models would have you believe that solar state is irrelevant to global temperature in spite of the fact that the overall Holocene data says otherwise quite convincingly.

I disagree with your assesment. Most papers I have read agree that solar output was likely a primary driver of medium term trends prior to the last 100 years, and that the corelation falls apart in the last 50 years as something else has become the primary driver. I think that part of the problem is that most people don't read the literature. They read WWF or greenpeace, or they read skeptic blogs, or at best they read both. This gives a very skewed perspective on what the science really says. The blogs (on both sides) are interested in hits. This is how they make money. The science is not really that interesting and is filled with "however" and "more research is needed" caveats. Reporting on the literature will not result in hits. Instead they weave naratives complete with antagonists. On one side it's the evil oil companies and their puppets. On the other it's the grant chaising scientists. If you believe the naratives it is easy to conclude that any work done by the other side is the result of lies, manipulation, and incompetence. In fact science is iterative. Steig tried a novel approach. O'Donnel likely improved upon it. There will be further work in the field which will improve our understanding further. Booring, but good.

Politics and science make poor bedfellows

Here at least we agree :)

It is not true that satellites show cooling from 1980 to 2011. In fact, quite the opposite. They agree with land based measurements: http://www.woodfortrees.org/plot/uah/from:1980/to:2011/plot/rss/from:1980/to:2011/trend/plot/rss/from:1980/to:2011

It is also not true that O'Donnel found cooling in Antarctica in his critique of Steig 2009. He found warming. It is also not clear that O'Donnel's methods are better. Perhaps they are, but if so, this doesn't make the authors of Steig 2009 liars or incompetent. There will surely be a response to O'Donnel 2010 that further improves the results. This does not make the authors of O'Donnel 2010 liars or incompetent.

Watts has been able to find some rural stations that show no warming. This is not surprising. If you aggregate the results (as has been done in the scientific literature) you will find that well placed stations show more warming. I agree that this is not what he had hoped to find, and he has done his best to spin the results by focusing on key weather stations and ignoring the bigger picture.

The last decade was the warmest on record. It can hardly be considered a cooling phase. The decade was ended with the hottest year on record. I recommend visiting http://www.woodfortrees.org/. This site lets you plot the data from various sources and compare against various forcings. Add a trend line to the data and judge for yourself whether the last decade is in line with the trend or represents a cooling phase. Here is an example of the CRU data and trend line: http://www.woodfortrees.org/plot/hadcrut3vgl/from:1970/to:2011/plot/hadcrut3vgl/from:1970/to:2011/trend

Watts has been able to find some rural stations that show no warming. This is not surprising. If you aggregate the results (as has been done in the scientific literature) you will find that well placed stations show more warming. I agree that this is not what he had hoped to find, and he has done his best to spin the results by focusing on key weather stations and ignoring the bigger picture.

The last decade was the warmest on record. It can hardly be considered a cooling phase. The decade was ended with the hottest year on record. I recommend visiting http://www.woodfortrees.org/. This site lets you plot the data from various sources and compare against various forcings. Add a trend line to the data and judge for yourself whether the last decade is in line with the trend or represents a cooling phase. Here is an example of the CRU data and trend line: http://www.woodfortrees.org/plot/hadcrut3vgl/from:1970/to:2011/plot/hadcrut3vgl/from:1970/to:2011/trend

Climate has a well documented 60 year periodicity, on top of the about 1C/century natural warming of the last two centuries.

about 30 years up 0.8C like 1910-1940
then 30 years down 0.2C like 1940-1970
then 30 years up 0.8C like 1970-1998
then a bit down like the last decade

The graph of satellite measured temperatures is here

http://www.woodfortrees.org/plot/rss/normalise/mean:12

and shows global cooling for 12 years now. The downward trend is like to continue, according to the natural periodicity, for another 20 years or so.

If you are not yet convinced check here
http://www.bilderbergmeetings.org/participants_2010.html
http://www.bilderbergmeetings.org/meeting_2010.html
how top government representatives, Peter Orszag, the director of the Office of Management and Budget and Robert Rubin, co-chairman of the Council on Foreign Relations, attended last June a leadership conference with global cooling on the agenda after which any mention of global warming was removed
http://www.climateweeknyc2010.org/
from the NYC climate conference last August.

The main fact about the far-north is that temperatures are not measured there. Not by satellites, not by regular stations.

The warming there is simply made up: "estimated" in the words of Jim Hansen.

See the point 1) in

http://climateprogress.org/2010/06/03/nasa-giss-james-hansen-study-global-warming-record-hottest-year/

With such "estimates" Hansen makes every year as warm as he wants.

Satellites show clearly cooling for more than 12 years.

http://www.woodfortrees.org/plot/rss/from:1979

The NASA-GISS data is made up by "estimating" heating at the completely unmeasured Arctic, as its director, James Hansen, declares openly. Satellites - the best data we have - show cooling for more than 12 years now. http://www.woodfortrees.org/plot/rss/from:1979 You can see here by how much NASA-GISS fakes the data (in red) compared to satellites (in green) http://www.woodfortrees.org/plot/gistemp/mean:12/from:1979/normalise/plot/rss/normalise/mean:12 The AGW is completely contradicted by all measurements.

The NASA-GISS data is made up by "estimating" heating at the completely unmeasured Arctic, as its director, James Hansen, declares openly. Satellites - the best data we have - show cooling for more than 12 years now. http://www.woodfortrees.org/plot/rss/from:1979 You can see here by how much NASA-GISS fakes the data (in red) compared to satellites (in green) http://www.woodfortrees.org/plot/gistemp/mean:12/from:1979/normalise/plot/rss/normalise/mean:12 The AGW is completely contradicted by all measurements.