My mistake. Thanks for correcting.

XKCD would have done well to include the error bars. They do illustrate this additional variability towards the right side between 16,000 and 15,500. If you include the error bars you can see that there is no contradiction. Even still, Marcotte was published in 2013. We're about 0.3C hotter now than the hottest observed temperature at that time: http://woodfortrees.org/plot/g... . That may very well exceed even the error bars and cover that last 25%.

The fact that it will not annihilate all life on Earth is a rather low bar. Is there any negative or costly behaviour that could not be justified with that logic? It's the Alfred E Neuman cost/benefit analysis: "It's not going to end life on Earth, so what's the big deal?"

Not quite. We reached the peak of the current interglacial about 8000 years ago. That peak is the result of Milankovitch cycles and the carbon, albedo, and other feedbacks - just as the peaks that came before. Temperatures have been falling slowly since then until the last 150 years when we increased atmospheric CO2 by about 70% by burning fossil fuels. Temperatures have risen along with the recent CO2 increase, just as you'd expect. The question she's trying to answer is, if we stopped releasing CO2 today, how much more warming would we observe just due to the CO2 we've already released. She uses the CO2 and temperature correlation over the previous glacial/interglacial periods to estimate the impact of CO2 on temperatures.

Gavin Schmidt shows why this is flawed and, given our current circumstances, likely to overestimate the impact. Here is a snippet: "In the previous post, I outlined how the combination of carbon cycle feedbacks to the Milankovitch forcing and the climate system response to CO2 gives rise to this correlation and that – by itself – it can’t be used to define the latter term. Furthermore, because the regression is being defined over ice age cycles where the biggest changes are related to the (now disappeared) North American and Fenno-Scandanavian ice sheets, the regression might well be much less for situations where only Greenland and West Antarctica are 'in play'."

Yes, but physics.

There have been several glacial/interglacial periods over the last 120,000 years. The peak of the current interglacial occurred about 8000 years ago. Since then temperatures have been slowly falling... up until about 150 years ago when something happened and temperatures dramatically reversed course.. Here's just the last 20,000 years by XKCD: http://xkcd.com/1732/

I hope not...

I think the XKCD comic is rather more clever as he uses peer reviewed science. Your other perspective presumes that temperatures in Greenland represent temperatures around the world. That's not going to work. It looks like he snipped only certain parts though as using the whole core wouldn't fool "even the dimmest denier at WUWT" as Sue explains here: http://blog.hotwhopper.com/201...

James Hanson, the previous director of NASA GISS and Gavin's former boss, weighs in with his own perspective. In a comment to the post he says in part: There are various technical issues with both Schmittner and Snyder approaches that lead them toward their low and high values. Suffice it to say that I expect the true answer lie between the two, but closer to Snyder’s. The evidence favors a temperature change in the range ~4-5C for LGM-Holocene, and thus a fast-feedback climate sensitivity close to 3C or a bit larger. This then leads to an ESS sensitivity ~6C or somewhat higher as discussed in our 2013 paper. http://www.realclimate.org/ind...

According to Gavin Schmidt, the director of NASA Goddard Institute for Space Studies: "The paper claims that ESS is ~9C and that this implies that the long term committed warming from today’s CO2 levels is a further 3-7C. This is simply wrong." He goes on to show why: http://www.realclimate.org/ind...

What they end up doing is offering several contradictory theories in an attempt to undermine the consilience of evidence. This is a result of attacking the theory piecemeal rather than addressing the cohesive theory. A contrarian will say "Not A because Y and not B because Z" even though Y and Z are incompatible. This study examines the mechanism that allows contrarians to hold these impossible views.

The paper gives numerous examples of high profile contrarians holding several incompatible views. There are even examples where these incompatible views are expressed within a single publication. I encourage you to take a look.

You may also want to look at consilience to understand why it is a flawed question to to ask for one particular piece of evidence in favor of a conclusion or to think that undermining that one piece of evidence by whatever means necessary does not undermine the theory. The section "In history" is particularly instructive.

There was a time in the satellite record when you could show that there has been little warming since 1997, and no warming prior to 1997, but significant warming over the whole period: http://phosphorus.github.io/ap...

XD

What, every single group that does temperature reconstructions is "removing stuff" and just happen to end up with the exact same answer? That's one hell of a conspiracy theory! It's item 4 on the conspiracy theory detector.

So, nothing to do with the El Nino? That's item 10 on the conspiracy theory detector.

That one's off the chart.

But isn't discussing global temperatures so is not really relevant to our discussion...

Well, yeah :)

Also not discussing global temperatures...

We've already got one, and as I've shown, the data fits quite well!

Yes. Clue #7

Yes. That's got to be frustrating given how well they have!

Because you're losing our bet so badly and because of how cocky and condescending you were when you entered it and because you're not particularly fond of the taste of crow?

We've blown past where we were even 6000 years ago at the peak of the current inter-glacial. And FAST! It's all occurred since industrialization.

Not even close.

The cyclical variations from PDO/ENSO/etc on top of the secular warming from CO2 explain each peak and valley in the temperature record quite well. It is naive to think that you would have a monotonic rise in temperatures that matched the monotonic rise in CO2. This is certainly not what the models show.

Here's a neat tool you can use to explore this. Set CO2 to 2.4 and PDO to 0.13 and you already have a pretty good match to the temperature record.

Here's the latest evidence that the latest evidence that Russia was behind the DNC hack.