I’m not surprised that some reconstructions show higher temperatures than others. I am also not surprised that one of those higher temperature reconstructions was based upon data from the Sargasso Sea, which tends to be warm. I’d expect warmer estimates from warmer regions, just like I’d expect cooler temperatures from cooler regions. More importantly though, the Sargasso Sea paper does not look like a global reconstruction. It looks like a reconstruction of surface temperatures at the Sargasso Sea, which indicates that there may have been some kind of event in the Sargasso Sea and by inference large parts of the Northern hemisphere as well– fine. It doesn’t say whether the change was global nor does it really give a global average temperature. You, and Climate Audit as well actually, are taking local (albeit large local) for global.

I can’t find any official EPICA statements to back up what you claim.

You are correct, though, the real question is “how much are we responsible?” EPICA’s CO2 numbers do not look good for the argument that we have nothing to do with rising temperatures.

http://www.sciencemag.org/cgi/content/abstract/274/5292/1503?rbfvrToken=b3527f8140d1ddfd7f0fdac765ac49b01f52eacb

And the EPICA cores I linked to earlier support the same conclusion. Even more critically, the real contention isn’t ‘is the Earth getting warmer?’ because it certainly is. The real question is ‘is it truly anthropogenic?’. At that point, even if the current temp is higher than the MWP it means nothing. Interglacial temps have been higher than the current temp before. Indeed, the EPICA group thinks the evidence indicates that the Earth is currently in a long-term interglacial period of unusually high - but naturally forced - temps.

http://www.nature.com/nature/journal/v429/n6992/abs/nature02599.html

My criteria for referenced data really all boil down to my being able to find things. My impatience over the matter stems from my arguing too much with creationists who tend to cite as obscurely as possible, apparently to disguise the fact that more often than not the citations are either ‘ghost’ citations or were greatly misrepresented by the people citing them.

Yes, I did write “it didn’t happen”. I then explained what I meant by that statement, that the MWP was “warm relative to adjacent years but not nearly as warm as claimed by the ’skeptics’ and not warm compared to today as claimed by the skeptics”. The NOAA page I cited even specifies something similar– “The idea of a global or hemispheric “Medieval Warm Period” that was warmer than today however, has turned out to be incorrect.” Take a look at Monckton’s graph, which is eerily like a fifteen year old IPCC graph. That huge medieval hump (relative to modern temperatures) on his graph isn’t supportable, as far as I can tell. Most reconstructions give something more like this, with current temperatures clearly higher than any medieval hump. It was at this kind of “medieval warm period” that my statement was aimed. That kind of event didn’t happen, though something more mild could have.

The point I was originally making was simple - one of your three refutations to Monckton’s piece was that the MWP “didn’t happen”. Sorry - it did. As you admit, the debate over the intensity of the MWP is still up in the air, but it is an important part of any discussion of global warming.

I must admit that I am fascinated that virtually all of your refutations of Monckton in this piece/thread come from RealClimate or its contributors. Even the NOAA article is a reference to Mann, etc.

One of your comments was flagged for moderation– probably because of the number of links.

I am not going to argue with you about what I meant. Not your fault. Its mine. I realized the problem and I corrected it the only way I am able– by telling you. I tried to clarify in my first response to you– “warm relative to adjacent years but not nearly as warm as claimed by the ’skeptics’ and not warm compared to today as claimed by the skeptics” and I tried again latter.

And no, last names and general area of research are not sufficient. I can find ‘Bransfield’ and ‘EPICA’. And I can find articles by people with the names you gave. What I can’t find is the particular articles and the particular points in those articles that you want me to think about. That is the problem, not lack of information. I don’t have time to try to 1) find the articles you allude to 2) read your mind to extract what you find significant in those articles and 3) construct your argument for you so that I may 4) then respond to it.

Now, I’ve read what you suggested. What point do you want to make? That we don’t really know much?

The intensity and magnitude of the MWP are still up in the air, as it were. Some proxies seem to indicate the height of the MWP was warmer than now, others that it was not. The EPICA cores indicate that previous interglacial periods were much warmer than contemporary temps, other long-term paleoclimate proxies don’t show that or are less extreme in their indications.

That is quite where I started, but it isn’t from it either. The MWP doesn’t look like a significant enough event to invoke as a counter-point to modern warming.

Also, forgive me if I assumed that you, someone who spends much more time than I writing about global warming, were already familiar with EPICA, the Bransfield ice cores, or the Khim, Yoon, Kang, Bahk (2002) paper disclosing the strong evidence that the MWP/LIA sequence was global.

http://www.ingentaconnect.com/content/ap/qr/2002/00000058/00000003/art02371

In my own defense, citing the names of the authors of papers or the specific evidence referenced is not ‘vague and hand-wavy’ in my book. If it would take you hours to find info on the EPICA cores, I suggest a new search engine for you

http://www.google.com/search?hl=en&safe=off&client=firefox-a&rls=org.mozilla%3Aen-US%3Aofficial&hs=Jmc&q=EPICA+cores+&btnG=Search

Or that you start here

http://www.ncdc.noaa.gov/paleo/icecore/antarctica/domec/domec_epica_data.html

http://news.bbc.co.uk/2/hi/science/nature/3792209.stm

and even

http://www.climateaudit.org/?p=1110

{Why not? If you want to fall back to RealClimate, please also reference Climateaudit]

The intensity and magnitude of the MWP are still up in the air, as it were. Some proxies seem to indicate the height of the MWP was warmer than now, others that it was not. The EPICA cores indicate that previous interglacial periods were much warmer than contemporary temps, other long-term paleoclimate proxies don’t show that or are less extreme in their indications.

Since you were free in implying that I am a charlatan, let me be equally blunt: the fact that you write about global warming as much as you do and didn’t know about EPICA and Bransfield off the top of your head implies that you need to get more of your data from original sources.

Just for clarity, you do realize, right, that by “doesn’t exist” I mean “doesn’t exist as any significant feature of global climate feature as used in the arguments of global warming deniers”? I don’t mean that, literally, there are no average temperature changes over that time frame. I assumed this was obvious from the context and from the other posts from this blog that I cited. And it was certainly obvious from my first reply to you. There is a hump in the temperatures around 900 or so followed by a drop. (I didn’t actually say anything about the LIA. I’m not sure why you are leaping at that one.) There is is a steep rise starting in about 1900 and by 1941 or so it passed the medieval high. More importantly, the sharpness of the rise is nothing like what is seen around 900, so it doesn’t make sense to attribute the two to the same cause, as the skeptics would have it. Furthermore, if you look at the graph, most– not all– of the reconstructions show pretty shallow rise and fall– in other words, they show nothing that could even come close to “offsetting” the modern warming.

Second and not to be rude, if you have support for you statements, please cite them and cite them fully enough that I can find them without crawling the web for hours. At the very least, provide the name of the damned article. Vague hand-wavy citations are the tools of charlatans. You don’t want to give the wrong impression. Besides, I get quickly annoyed when people expect me to not only read material supporting their position– fair enough– but also to go out and find that material for them.

I know of a number of attempts to discredit Mann– I know, I should say, of a number of failed attempts. Which do you mean?

You want to convince me that the current warming trend is anthropogenic? Fine, let’s talk carbon loads, albedo, and just how much sulfate aerosols affected the cooling of the 1965-1985 period. Let’s debate solar loads, cloud cover variations, and the various models in play. But don’t try to convince me that the MWP/LIA cycle, one of the most successful examples of how inter-disciplinary research can provide a more precise picture of the world (and one of the best-documented long-term climate events ever) didn’t happen! Especially when you have to refute the National Academy of Sciences’ most recent statements about the LIA.

Further, if you want to support Mann’s work, please use a source other than RealClimate - after all, Mann is their most prominent contributor!

Actually, Deep, you didn’t look very deep. The “medieval warming period” was 1) local and so hardly indicative of a global climate and 2) warm relative to adjacent years but not nearly as warm as claimed by the ’skeptics’ and not warm compared to today as claimed by the skeptics. The information isn’t hard to come by.

Um… Deep, you named four people. How is that “writing off everyone”? Little bit of an overstatement isn’t it?

So much for the Bransfield Basin ice cores, viniculture research, ocean sediment reasearch, and palynology, I suppose.