Guest post by by Michael A. Lewis, Ph.D.
In my work as an archaeologist in Alaska, I spent a good swat of my time hiking through forests along the Yukon River, scrambling over piles of driftwood along the northwest coast and pulling roof beams and house posts out of 2,000 year-old dwelling sites on St. Lawrence Island.
The object of my quest? Tree rings.
From hundreds of core samples and cross-section “cookies,” I developed a regional tree ring climate chronology that I compared with archaeological records of human population movements across the Bering Strait over the past 2,500 years. One thing stood out clearly in both independent data sets:
About a thousand years ago, a remarkable change occurred among all Arctic peoples from Siberia to Greenland in a period of less than 200 years. People moved long distances. New technologies supplanted old. Ground slate harpoon blades replaced chipped stone. The sea mammal hunting Thule people of Northern Canada completely replaced the land based Dorset culture that had been in place for thousands of years. The Inuit language spread from Northwestern Alaska to Greenland, the greatest areal extent of any language on earth. Whale hunters migrated across northern Canada, following whales across the ice-free Arctic Ocean.
The tree ring record reflected these cultural changes. Across the Bering Strait and into Interior Alaska, increasing temperatures and changing precipitation patterns were recorded in tree rings from Siberia to Fort Yukon around 1,000 BP.
Something was afoot and my further research revealed the Alaskan signature of the Medieval Warming Period (MWP) that had been experienced across North America, Iceland, Greenland and Europe.
So you can imagine my surprise to see the infamous Hockey Stick graph appear in the 2001 IPCC Report, completely missing the MWP that I knew from multiple independent data sets, as well as the subsequent Little Ice Age that brought to an end the European occupation of Greenland. Later IPCC reports and subsequent media hype increased my discomfort with the concepts of Anthropogenic Global Warming and the insistence that presently observed climate change is driven primarily by human greenhouse gas emissions.
Archaeologists are “hard” scientists, driven by data, uniformitarianism, and a deep time perspective on human and natural history. My research demonstrated that humans had reacted to complex climate variation from Lake Baikal to Greenland over the past 100,000 years, climate variations that occurred in the complete absence of human greenhouse gas emissions. I see no reason to accept the automatic assumption that observed rising CO2 levels are solely the result of human emissions, or that the observed increase is significant with respect to the geological record of CO2 and temperature fluctuations.
It makes much more sense to me to view the present dynamic climatic situation in light of historical and geological records, particularly those of the past 2,000 years, for which we have independent data sets to confirm our findings. Dr. Syun-Ichi Akasofu has presented this perspective with remarkable clarity in his paper, On the recovery from the Little Ice Age, Natural Science, Vol.2, No.11, 1211-1224 (2010) http://www.scirp.org/journal/NS/
From this perspective, observed climate fluctuation is viewed as a continuation of natural geological and physical processes, in this case, recovery from the Little Ice Age.
This is not to say that human emissions do not contribute to climate fluctuation. However, we cannot understand the extent of human contributions until we fully understand the ongoing natural forces that have shaped the Earth’s climate for millennia before humans appeared on the scene.
Oh, and about smoking… in those days of yore in the wilds of Alaska, I used to smoke a pipe to wile away the lonely hours in tents and log cabins across the Arctic landscape. As my work shifted from field to laboratory, I gradually eschewed the fragrant clouds of tobacco smoke, until the day I realized I no longer enjoyed smoking.
I’m still working on the Global Warming part.
In the above article, you say, ” Little Ice Age that brought to an end the European occupation of Iceland. ” I think that should read Greenland instead of Iceland.
I really like that graph, I’m going to add it to http://wermenh.com/climate/6000.html , my look at the glacial retreat 5000-7000 years ago. Is there an English variant of the site or paper it’s from?
Piers Corbyn was on FoxNews this morning. Seems like Fox will be covering Climate Change more in the coming year or 2. 🙂
Did you mean to say “brought to an end the European occupation of Iceland” or “brought to an end the European occupation of [Greenland]”?
Welcome. Your perspectives on the Arctic cultures are very interesting.
“…….the subsequent Little Ice Age that brought to an end the European occupation of Iceland.” I think you mean Greenland. Iceland has remained European since the Vikings first arrived there, pretty well at the begining of the Medieaval Warm Period.
We represent Sue Grabbit & Runne, special litigation attorneys to Michael Mann and the Team.
We wish to inform you that all historical climate data, not previously approved by the Team, are deemed false and may not be publicly stated without incurring severe legal and financial penalties.
We require you to make an immediate public statement retracting the contents of the above article, as well as confirming in writing you had misinterpreted your data and that you now accept the so called Medieval Warming Period did not exist.
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Excellent post. Glad you quit smoking, and also glad you enjoyed it while you did smoke. One correction: Europeans still occupy Iceland, but left Greenland after the MWP, as you certainly know.
Your description of walking through the Alaskan landscape brings to mind exactly why, as I get older, I am moving further and further away from concrete.
Many thanks for a good article Michael.
I noted one typo: “as well as the subsequent Little Ice Age that brought to an end the European occupation of Iceland”. Should be “…an end the European occupation of Greenland”.
Regards
Agust
Iceland
The Hantemirov graph indicates the MWP was a fairly modest warm spell, compared to that around 1000BC for example. Any ideas why the knowledge diffusion you document took place then, rather than in earlier cycles?
Great article!
typo:
“… as well as the subsequent Little Ice Age that brought to an end the European occupation of Iceland. ”
That should be Greenland.
Shouldn’t the sentence: “as well as the subsequent Little Ice Age that brought to an end the European occupation of Iceland” read “bla bla bla …. European occupation of Greenland”?
“The tree ring record reflected these cultural changes. ”
Those must be some tree rings, Doctor Lewis.
Great post! Thank you for taking the time to share your experiences with all of us.
I can still recall the day some fool claimed that the Medieval Warming Period and the Little Ice Age did not really happen! It was as if someone walked up and claimed the sun really rises in the south!
Re: “European occupation of Iceland”. Should be ‘Greenland’
You mean “the European occupation of GREENLAND” Iceland is still occupied.
There you go, bringing in “hard” science again. We all know the “real” science is being done by the computer models that show for a fact that mankind is to blame for the runaway temperatures that we are now experiencing.
/sarc off
Simple and to the point. I wonder how the MWP has been erased in so many peoples minds? Thank you for this post. We need to ask why has Hansen, Gore and others pushed an agenda so hard that they have fabricated a new history.
Typo: it was the European settlements in Greenland that perished in the LIA. The icelanders survived the LIA, but only just.
The scary thing about that graph is how quickly it can swing from warm to cold.
This word you keep using, consensus. I do not think it means what you think it means.
However, we cannot understand the extent of human contributions until we fully understand the ongoing natural forces that have shaped the Earth’s climate for millennia before humans appeared on the scene.
Truer words were never spoken…
Thank you for this post Michael A. Lewis. It gave me great satisfaction to read it and hope you “hard” scientists can get together and publish a paper that discredits the ‘hockey stick’.
You certainly have all the ammunition you need. Where you will find a publisher I cannot say and what does that say about the world we live in today?
Fantastic article. This demonstrates why we should always insist upon an interdisciplinary perspective on human questions and avoid taking for granted the untested methodologies of such “new sciences” as those practiced by “climate scientists.” Anthropologists in the Boasian tradition are taught the “four field” approach – we need archaeology, cultural anthropology, anthropological linguistics, and physical anthropology working in concert to make reliable reconstructions of past human societies. Likewise, those studying the earth’s climate history would be well advised to at least occasionally remove their heads from their computer models and consult with colleagues, such as Professor Lewis, who can bring a different, and possible corrective, perspective to bear on some of the more dubious warrants of their arguments.
Thank you, Dr. Lewis!