Denier weirdness: how an old block of wood changed climate physics forever, not!

There's an article that's been doing the rounds of denier blogs over the past few days. It finally was picked up by Anthony Watts and copied and pasted onto his blog, WUWT. It's a two part copy and paste - of something science denier Larry Bell wrote and something that climate crank Pierre Gosselin wrote. (Archived here.)

The article is about what could be Germany's version of Denier Don Easterbrook, or not as the case may be. The article is about Christian Schlüchter, an emeritus professor with the Institut für Geologie at Universität Bern. According to the article at WUWT, the good professor is a climate science denier. I'm not so sure about that.

A find that was heralded by scientists

The article starts with this odd sentence:

Dr. Christian Schlüchter’s discovery of 4,000-year-old chunks of wood at the leading edge of a Swiss glacier was clearly not cheered by many members of the global warming doom-and-gloom science orthodoxy.

Now the reason I say the sentence is odd is not simply because scientists usually are delighted with new discoveries. There were two more reasons. Firstly, when I did a search to see if I could find a paper on the subject, I found that it was cited no less than 123 times according to Google Scholar. That doesn't signify the paper being "not cheered". Quite the reverse. Particularly since it was published in The Holocene, not the highest profile journal, though a very respectable publication.

Christian Schlüchter collaborates with Thomas F. Stocker - Co-Chair of IPCC WG1

The second reason I found the sentence odd was that the paper by Christian Schlüchter was coauthored by Ulrich E. Joerin and Thomas F. Stocker. I'm not familiar with the work of Ulrich Joerin but most readers will be familiar with Thomas Stocker. He was co-chair of Working Group 1 of the IPCC. A "warmist" if ever there was one. That would be particularly galling to Pierre Gosselin, whose blog article was copied and pasted at WUWT below Larry Bell's. If he knew about it. Pierre has written rants about Thomas Stocker in the past.



The first paper I came across on the topic to which Christian Schlüchter is referring has the following abstract (my paras):

Abstract: Subfossil remains of wood and peat from six Swiss glaciers found in proglacial fluvial sediments indicate that glaciers were smaller than the 1985 reference level and climatic conditions allowed vegetation growth in now glaciated basins. An extended data set of Swiss glacier recessions consisting of 143 radiocarbon dates is presented to improve the chronology of glacier fluctuations.

A comparison with other archives and dated glacier advances suggests 12 major recession periods occurring at 9850-9600, 9300-8650, 8550-8050, 7700-7550, 7450-6550, 6150-5950, 5700-5500, 5200-4400, 4300-3400, 2800-2700, 2150-1850, 1400-1200 cal. yr BP.

It is proposed that major glacier fluctuations occurred on a multicentennial scale with a changing pattern during the course of the Holocene. After the Younger Dryas, glaciers receded to a smaller extent and prolonged recessions occurred repeatedly, culminating around 7 cal. kyr BP. After a transition around 6 cal. kyr BP weak fluctuations around the present level dominated.

After 3.6 cal. kyr BP less frequent recessions interrupted the trend to advanced glaciers peaking with the prominent ‘Little Ice Age’. This trend is in line with a continuous decrease of summer insolation during the Holocene.

Climate has changed before

Now the WUWT article suggests that finding and dating these blocks of wood means that climate has changed before. I'd agree. The paper suggests reasons for the change in climate in the Swiss Alps in the region of these glaciers. The conclusion suggests that the forcing was via changes in the sea surface temperature in the North Atlantic which was in turn affected by changes in summer insolation:

It is important to recognize that this natural variability of glacier extent, which occurs on a centennial timescale, is superimposed on a much longer term, multimillennial-scale trend towards increased glacier extent culminating in the ‘Little Ice Age’. This is indicated in our data as a progressively reduced occurrence of wood and peat remnants through the course of the Holocene, which is consistent with a long-term reduction of sea surface temperatures in the North Atlantic. The multimillennial trend that is indicated in our data, therefore, is likely forced by changes in summer insolation and hence of astronomical origin. Studies attempting to identify the amplitudes of glacier fluctuations will help to improve the understanding of the pattern and forcings of climate change during the Holocene. 

Climate has changed before, but not as fast or as much as it is now, and for different reasons. Today's climate change is not because of changes in summer insolation. It's from the rapid increase in atmospheric carbon dioxide.

In case you are wondering how this old-ish paper (from 2006) is being spun at WUWT, here are some snippets (archived here):

Dr. Christian Schlüchter’s discovery of 4,000-year-old chunks of wood at the leading edge of a Swiss glacier was clearly not cheered by many members of the global warming doom-and-gloom science orthodoxy.

This finding indicated that the Alps were pretty nearly glacier-free at that time, disproving accepted theories that they only began retreating after the end of the little ice age in the mid-19th century. As he concluded, the region had once been much warmer than today, with “a wild landscape and wide flowing river.”

The paper that I found doesn't suggest that the Alps were "pretty nearly glacier-free" 4,000 years ago. It talks about the advance and retreat of glaciers, not their total disappearance. Larry Bell goes on to suggest:

Dr. Schlüchter’s report might have been more conveniently dismissed by the entrenched global warming establishment were it not for his distinguished reputation as a giant in the field of geology and paleoclimatology who has authored/coauthored more than 250 papers and is a professor emeritus at the University of Bern in Switzerland. 

First of all, the paper that I found didn't have Christian Schlüchter as the lead author. So although he may have discovered the bits of wood, it would appear that the research was done by other scientists. There was no paper in the references where he was the lead author.

I did find an earlier paper on the subject, from 2001, where Christian Schlüchter was also listed as a co-author. It too was published in The Holocene. You can download the pdf file here. That paper was again very popular, with 164 citations, according to Google Scholar. Although Thomas Stocker wasn't listed as an author, he was involved. He was thanked in the Acknowledgements for assisting the lead author Anne Hormes: "We offer our sincere thanks to Thomas Stocker for co-referencing Anne’s thesis."

A target of scorn?

Now do you think that papers on the subject that have been cited more than a hundred times and had the blessing of Thomas Stocker, are consistent with the following spin?

Following the ancient forest evidence discovery Schlüchter became a target of scorn. As he observes in the interview, “I wasn’t supposed to find that chunk of wood because I didn’t belong to the close-knit circle of Holocene and climate researchers. My findings thus caught many experts off guard: Now an ‘amateur’ had found something that the [more recent time-focused] Holocene and climate experts should have found.”

That's funny. Just a couple of paras earlier, he was hailed as having a "distinguished reputation as a giant in the field of geology and paleoclimatology". Now he's an "amateur" and a "target of scorn"? I think that maybe "amateur" refers to him not being a specialist on the Holocene. His publication history seems to be mainly focused on earlier times. The "target of scorn" was made up hyperbole from Larry Bell.

Then there was this from Larry Bell:

Then he made himself even more unpopular thanks to a recent interview titled “Our Society is Fundamentally Dishonest” which appeared in the Swiss publication Der Bund where he criticized the U.N.-dominated institutional climate science hierarchy for extreme tunnel vision and political contamination. 

So he's taken a shot at the IPCC. That brings me back to the comparison with Denier Don Easterbrook. Both are emeritus professors of geology. From the WUWT article, it looks as if both are denying the current cause of global warming on the grounds that "climate has changed before". Which would be pretty dumb. By looking at the how and the why of past climate change, scientists help us understand what we can expect as climate continues to change over the next few decades and centuries. Even though the cause of climate change in the Swiss Alps was different to what's causing the current change, it will still help us understand what to expect over time.

On the other hand, if you read the interview itself (or the Google translation), it's not at all clear that Christian Schlüchter does reject climate science. The interviewer is asking some leading questions, however the responses don't necessarily indicate that Christian Schlüchter rejects the greenhouse effect. In fact he does say at one point, in response to a question about the role of CO2 in the advance and retreat of glaciers:

CO2 plays a role. But you can not explain it for the sole reason, without explaining the motions of glaciers in the 1980s. In addition, one would have to explain the role of the CO 2 played at the major geological "turning points" as 115,000 years ago.

Which is fair enough.

So is this just another beat up at WUWT? Probably. Deniers will twist anything and everything to reject science.

Before you read the nonsense in the comments, you might like to check out Thomas Stocker's presentation of the IPCC WG1 report.

From the WUWT comments

Many of the comments were the predictable "climate has changed before therefore the greenhouse effect isn't real" - or similar stupidity. A lot of people didn't know the find was made in the 1990s. There was a lot of other silliness in the thread, as usual. Deniers are only too willing to believe the nonsense written at WUWT. Most of them never check facts. There were wrong comments about everything from Marcott13 to arguing that the Swiss Alps are the entire world.

archonix seems to think that climate change in the Swiss Alps meant climate change all over the world. Or at the very least thinks that climate can change for only one reason - and says (extract):

August 8, 2014 at 5:55 am
Nick Stokes (and indeed others) seem to be missing the point here: the evidence presented demonstrates that climate changes abruptly without human intervention. Indeed a great deal of evidence has accumulated by now (as can be seen if you browse WUWT) that world climate has changed abruptly many times without that intervention, and in spite of apparent atmospheric CO2 levels.

The Ghost Of Big Jim Cooley says:

August 8, 2014 at 12:14 am
The knives will be out for him.

Mike Bromley the Kurd doesn't realise that the article is about stuff that was published more than a decade ago and says:

August 8, 2014 at 12:27 am
This is indeed great news, because it really cannot be refuted in any way. You cannot fake radiocarbon dating correlated with tree rings. Not the hockey stick tree rings, but just good old chronology done by counting back. Pretty hard to argue with. So what do they do? Make asses of themselves by heaping scorn on the discoverer.
Bravo Dr. Christian Schlüchter. Not just a fly in the ointment, but a goddamn jumbo jet.

Leigh says:

August 8, 2014 at 2:19 am
Boy, is he in trouble! 

mosomoso says:

August 8, 2014 at 2:52 am
Quick, climate scientists, find a volcano from the period. Re-write the wiki. And don’t mention the Optimum. Scramble! What do you think you’re hired for? Now’s the time to pay for the free drinks at Cancun. 

A lot of the comments were complaining about Nick Stokes, not the article itself. David Ball says:

August 8, 2014 at 6:56 am
I can no longer stomach reading Stokes posts. They contributing nothing but confusion, and are clearly intended to derail any constructive discussion. His intent is only to attract attention to himself. Like a child. 

So I scrolled up to see what all the fuss was about. You'll like this one. Nick Stokes says:

August 8, 2014 at 6:46 am
JustAnotherPoster says: August 8, 2014 at 6:28 am “The ENTIRE IPCC remit is that CO2 causes global warming.”

Yes. And arsenic will kill you. But that doesn’t mean that by avoiding arsenic, you are immortal. 

Some of them are finally getting the message. Bruce Cobb mightn't like the message but he's got it. He says:

August 8, 2014 at 6:20 am
Yes, but THIS time is different, because WE’RE doing it. Because shut up. 

---

Hormes, Anne, Benjamin U. Müller, and Christian Schlüchter. "The Alps with little ice: evidence for eight Holocene phases of reduced glacier extent in the Central Swiss Alps." The Holocene 11, no. 3 (2001): 255-265. doi: 10.1191/095968301675275728

Joerin, Ulrich E., Thomas F. Stocker, and Christian Schlüchter. "Multicentury glacier fluctuations in the Swiss Alps during the Holocene." The Holocene 16, no. 5 (2006): 697-704. doi: 10.1191/0959683606hl964rp