Claim: Climate change 'may' be responsible for the abrupt collapse of Tibetan civilization around 2000BC

From Washington State University: Closing the Case on an Ancient Archeological Mystery

Solving 4,000-year-old mystery helps WSU archeologist find useful resource for a warmer future

Barley cultivation in Jiuzhaigou National Park hasn't changed much in nearly 2,000 years. The park is located in the Min Shan mountain range, Northern Sichuan in South Western China. Credit: Washington State University

Barley cultivation in Jiuzhaigou National Park hasn’t changed much in nearly 2,000 years. The park is located in the Min Shan mountain range, Northern Sichuan in South Western China. Credit: Washington State University

PULLMAN, Wash.–Climate change may be responsible for the abrupt collapse of civilization on the fringes of the Tibetan Plateau around 2000 B.C.

WSU archaeologist Jade D’Alpoim Guedes and an international team of researchers found that cooling global temperatures at the end of the Holocene Climatic Optimum, a 4,000 year period of warm weather, would have made it impossible for ancient people on the Tibetan Plateau to cultivate millet, their primary food source.

Guedes’ team’s research recently was published online in the Proceedings of the National Academy of Sciences. Her results provide the first convincing explanation for why the area’s original inhabitants either left or so abruptly changed their lifestyles.

They also help explain the success of farmers who practiced wheat and barley agriculture in the region 300 years later.

Unlike millet, wheat and barley have high frost tolerance and a low heat requirement, making them ideally suited for the high altitudes and cold weather of eastern Tibet. Guedes argues this made the two crops an important facet of subsistence immediately after their introduction around 1700 B.C.

“Wheat and barley came in at the opportune moment, right when millets were losing their ability to be grown on the Tibetan Plateau,” Guedes said. “It was a really exciting pattern to notice. The introduction of wheat and barley really enabled Tibetan culture to take the form it has today, and their unique growth patterns may have played a crucial rule in the spread of these crops as staples across the vast region of East Asia.”

One offshoot of the research: The ancient millet seeds that fell out of cultivation on the Tibetan Plateau as the climate got colder might soon be useful again as the climate warms up.

“Right now, these millets have almost become forgotten crops,” Guedes said. “But due to their heat tolerance and high nutritional value, they may be once again be useful resources for a warmer future.”

An archaeological enigma

At Ashaonao, Haimenkou, and other archeological sites in the Tibetan highlands, researchers for years had noticed a growing trend. An abundance of ancient wheat and barley seeds found at the sites suggested the crops rapidly replaced millet as the staple food source of the region during the second millennium BCE.

The findings were puzzling considering that the scientific consensus of the time was the region’s climate would have actually favored millet, due to its shorter growing season, over wheat or barley.

The conundrum intrigued Guedes so she dove into the agronomy literature to investigate. She found agronomists tended to use a different measurement than archaeologists to determine whether crops can grow in cold, high altitude environments like the Tibetan Plateau. They used total growing degree days or the accumulated amount of heat plants need over their lifetime rather than the length of a growing season.

“My colleagues and I created a new model based off what we found in the literature,” Guedes said. “It revealed that global cooling would have made it impossible to grow millet in the Eastern Tibetan Highlands at this time but would have been amenable to growing wheat and barley. Our work turned over previous assumptions and explained why millet is no longer a staple crop in the area after 2000 BCE.”

Guedes’ work points to climate cooling as the culprit behind the collapse of early civilization on the Tibetan Plateau. Ironically, the region is today one of the areas experiencing the most rapid climate warming on the planet. There are some areas in the southeastern plateau where temperatures are 6 degrees Celsius higher than they were 200 years ago.

Rapid temperature increase is making it difficult for the region’s inhabitants to raise and breed yaks, a staple form of subsistence in the central Asian highlands, and grow cold weather crops, once again endangering their survival.

“So now we have a complete reversal and climate warming is having a big impact on the livelihood of smaller farmers on the Tibetan Plateau,” Guedes said.

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Grey Lensman

You cannot make this stuff up.
“model stops millet growing”
Or
They created a model which then showed.!!!!!!!!!!!!!!!!!!!!!!!!
Sorry, i am wincing with disdain.

menicholas

“You can not make this stuff up”
Sure, scoff. But numerous models runs and other models have confirmed the accuracy of the models more times than anyone can count.
Why are you anti-science?
/sarc off

Jon Lonergan

One model can’t confirm the accuracy of another model. That’s like saying one bigot agrees with the prejudices of another therefore it confirms it as true. Measurement (in the real world, not the world-model) is the necessary confirmation.

“My colleagues and I created a new model based off what we found in the literature,” Guedes said.
I would be more convinced if they created a model based ON the literature.
Things stand on bases. They fall off them.

Alx

The nature of science is to create models that reflect a natural process in a predictive way. When the models are able to predict a natural process or events consistently it is promoted to a theory. This process is often turned on its head. Make a model that has no predictive qualities and cannot be dis-proven and claim the model is accurate.
Climate models do have predictive qualities in terms of global temperature, unfortunately their predictive qualities are extremely poor. Accepting climate change would be like Newtonian mechanics being accepted after only by chance predicting correctly the path of a planet or two. Newtonian mechanics was made more accurate by relativity adjustments, but it’s predictive ability was well established.
The last 20 years show climate models inept in understanding the relationship of additional CO2 and global temperatures. Green house physics is sound, but it’s application within climate models is abysmally wrong.
Finally there are no models of extreme weather from CO2 or temperature increases, never mind predictive ones. It’s idle speculation in combination with frantic arm waving.

ShrNfr

It must have been all those Tibetans using cremation to get rid of their dead. Oops sorry, they use “sky burial”. Oh well. Anyway, there appears to have been an event that had global consequences around 2000 BCE. There is a bump in the carbon-14 curves and Egypt dissolved into its first intermediate period. They were mostly growing barley in the first millennium BCE from the written records. As it is, the current state of the Tibetan plateau is such that not a lot grows there due to the cold and altitude.

Justthinkin

I would really like to take her to Tibet for a year. Get her out of her ivory tower and show her the real world, not models. But I guess models are the go to now. Sad.

M Courtney

She would probably love that if you funded her research.
But you can’t blame her for working with what she has.

zemlik

I’ve seen those guys walk miles for some twigs for fire

joelobryan

She has carried out extensive field work in China and that area. She is a young, new academic in archaeology just needing grants to get tenure, as everyone new to field archaeology must get in order to publish and survive. Give her a break. I don’t see here where she is hyping Climate Change alarmism (via anthropogenic CO2) in this article.comment image?itok=M90t1V4D
… but then what guy wouldn’t want to take her to Tibet for a year??? or Tahiti?

Corey

It’s a magical place

D.J. Hawkins

@Corey
That’s Tahiti; just ask Phil Coulson.

Katherine

You have to give her props for checking agronomy literature. That’s considered thinking out of the box. And she used that literature to come up with her model. The mention of the Holocene Climatic Optimum also goes to show temperatures were warmer…until global cooling.

Gamecock

There are several known examples of ancients being forced to move due to a changing climate.
None were forced to move due to “climate change,” which wasn’t invented until the 20th century.

Jon Lonergan

Wasn’t Angkor Wat destroyed by the climate change of the non-existent Medieval Warm Period?

M Courtney

She found agronomists tended to use a different measurement than archaeologists to determine whether crops can grow in cold, high altitude environments like the Tibetan Plateau.

I wonder how long this lack of interdisciplinary awareness has been going on. It doesn’t sound like the sort of thing archaeologists are expected to be experts at in the first place.
And is it still happening in studies of South America or the Pacific Islands?

usurbrain

A lesson I learned very early in my life which was supposed to be a joke but I found to be VERY true, I forget the exact words from 1960 or so but – The higher your education the more you learn about less and less. Eventually, you learn all there is to know about nothing at all. and become an expert in nothing, It has amazed me the number of “experts” I have worked with (and for) that, although they had advanced degrees in their profession, knew absolutely nothing, zero, about other disciplines, absolutely necessary in the practical application, use, or even understanding of there area of expertise.
Many years ago a college grad would be strongly discouraged, even not permitted to immediately go into a Masters program without at least 3 -4 years of practical experience. My wife, whom graduated with a 4.0 GPA was refused admission into Grad school until she had 4 years of experience. Now, kids get their BS/A degree, can’t find a job, go on to get a MS degree, can’t find a job, get a PHD, and still can’t find a job – So the start teaching all of the up and coming students what (fill in your favorite discipline) is and how it works and why. And they have no knowledge of that topic other than what they have read about it or been lectured on by others with the same lack of real experience. They don’t even know what they don’t know, thus what they know is useless.

Intellectual curiosity & questioning present day scientific dogma, is no where present in the climate research done by most in this field. That’s sad for all mankind & this planet. What would Kepler think of these methods used today?

Alberta Slim

“Them that can….do; Them that can’t…teach

MarkW

Them that can’t teach … go into journalism.

“Them that can….do; Them that can’t…teach.”
And them that can’t teach, create models?
“So they start teaching all of the up and coming students”
Getting a PhD doesn’t guarantee finding a teaching position. Aside from fields offering good job opportunities outside of academia, the supply of PhDs substantially exceeds tenure track opportunities. The surplus ends up scraping by as adjuncts and/or underemployed in other positions. I suspect some of them spend a lot of time expressing their disappointment with the unfairness of the world in forums on the Internet. You may have seen a few of them commenting here.

jayhd

Archaeologists had better know how things work today before they draw any conclusions about how things worked in the period they are studying. That includes agronomy, engineering, transportation and every other discipline they may be trying to write about in ancient times.

Bohdan Burban

It’s not that long ago that archeologists did not subscribe one iota to the destructive power of earthquakes, preferring the power and might of mythical armies from undocumented lands.

Latitude

“Rapid temperature increase is making it difficult for the region’s inhabitants to raise and breed yaks”…….
My goodness, that’s awful………..maybe they should order some from Cuatro Light Cattle Co….in Florida

John Peter

Is that real or homogenized “Rapid temperature increase”?

Ray Boorman

Her “rapid temperature increase” stopping the yaks from surviving in Tibet is probably the same “r t i” that means polar bears cannot survive outside the Arctic – but don’t tell the people who breed them in zoos all around the planet, they may laugh at you.

ws1835

So as usual, we find that natural climate change is significant and has often affected human development. All without burning a single lump of coal. One would think the public in general would catch a clue after the umpteenth time this is discovered…….

The public has a pretty good BS indicator. It’s the journalists and politicians who need help.

emsnews

The warmer it is, the easier life is especially in colder regions. The destroyer of civilizations in the past has nearly always been colder weather, crop failures etc during cooling cycles. Like, say, the Dark Ages which were colder than the Roman Warm Period.

Gerry, England

Good point. And it shows how adaption can mitigate against a changing climate which is something the models always exclude. There is something interesting in the findings but then as is normal it goes off to La-La-Land. Is that a genuine increase in temperature or one of those that has been made up in the surface temperature records?

it is simple to adapt to warmth. all you need is water and air. evaporation does the rest. adapting to cold is the problem, because that requires energy.
if warming was a problem, the tropics would be a wasteland. instead they have the most abundant and varied life on earth.
Pick any place on earth. Where is the temperature too hot for life along the equator? Can you find a single spot outside of a volcano? Clearly, if there is no place on the equator too hot for life, warming cannot be a problem.
In contrast, there are vast regions of the planet too cold for anything except for the hardiest of species.

John Greenfraud

How to get a scientific article published in 2015.
1. Find regional temperature changes/population shifts in the past
2. Blame climate change excluding all other factors
3. Relate it to current climate change
4. Get article rubber stamped in pal review

asybot

And collect zillions in grants.

auto

And get funded to travel to ‘important’ seminars, conferences, etc. in agreeable places.
Like – ohhh – say, perhaps Paris, for example.
Good wine, great sights, good food, some lovely people – if you start speaking in French . . .
They, of course will demonstrate their superiority to your French, with their English.
Conversation is then in English – leaving two [2] winners – a result!!
We go to France four or so times a year. And love it!
Auto

emsnews

By the way, the claim that Tibet is warming is false. It is now cooling. The recent earthquake that killed the Mt. Everest climbers showed a lot more ice and snow than normal there before the avalanche happened. Ice and snow is increasing in the Alps and other mountains, too.
It is snowing more in Hawaii’s mountains, too.

must be global warming causing more ice and snow, increasing the weight on the tectonic plates, causing earthquakes. still waiting for the grant from big oil.

menicholas

So, the ancient Tibetans had earth destroying carbon economy too!
Who knew.

Exactly !!! Pre-Industrialization = Natural Climate Change

Alberta Slim

Yes all those Yak farts and of course, burning all the Yak poop…..
This caused global warming, which caused global cooling, which caused the Tibetans to die or move… etc., etc., etc., ad infinitum…………………..or something like that. For clarification, please ask a warmist.
/sarc

MarkW

People can adapt to a changing climate.
Who’d a thunk it.

only people in the past can adapt. people today cannot. if the temperature goes up more than 2 degrees we will star dying like flies. the IPCC is certain of this and are working hard to save us. They have a legally binding agreement for Paris that will outlaw summer.

She was doing good until the last two paragraphs. It would seem those 6 degrees arent actually supported in the literature. What a surprise.
http://onlinelibrary.wiley.com/doi/10.1002/joc.1956/full

bernie1815

Her apparent certainty about the temperature 200 years ago in Tibet stretches credulity.

Tony Hansen

Agreed Bernie. Now, 200 years ago… 1815…Tambora?

auto

Coming out of the Little Ice Age (LIA) – plus Tambora, maybe.
?? And how good are her proxies?
I doubt there were many thermometers there in 1815 [or so].
Auto

ozspeaksup

so does the claim about wheat doing well in cool climates.

It say’s they took Yak stool core samples from the time period being studied to come up with the temperature data. Y’all missed that part.

The broader issue here is the proper role of government climate science research. While Professor Guedes’ study may close the case on what happened in the past, it opens the question on what government should or should not be doing to help a societal group adjust to a changing climate.
Farmers and ranchers are fairly good at making short term weather decisions. It is hard to remember what happened 2,000 years ago. In my opinion research like this is good so long as we let the affected folks make the decisions that research like this brings to light,

Taphonomic

Article paywalled at: http://www.pnas.org/content/early/2015/04/14/1423708112.short
The abstract doesn’t mention anything about current warming. It makes me wonder if the last three paragraphs of the press release was just speculation to make the article seem more interesting.

Unaware that millet is a drought and heat tolerant grain and that barley is a cold tollerant short season grain, while studying grains in ancient cultures? The stupid, it burns. Millet is widely grown around the Sahara… But kudoes for going out and learning it…
Also the 4200 ky event is well known as a cold spike. Bond Event 3. Loads of civilizations ended then in cold and drought.
https://chiefio.wordpress.com/2011/11/03/akkadians-and-chad/

DirkH

Also, the German wikipedia says that Millet is now partially being replaced by corn in Africa, probably indicating that corn might be… heat-tolerant?
I guess she’ll learn that over time.

Robert of Ottawa

Rapid temperature increase is making it difficult for the region’s inhabitants to raise and breed yaks
Global warming kills Yaks!
Well, seriously, they admit it was warmer in the past, and the changes were natural. So why are they not natural now?

MarkW

Because this time, we have models.

asybot

Yaks, the polar bear of 4000 years ago.

Excerpted from article:

They used total growing degree days or the accumulated amount of heat plants need over their lifetime rather than the length of a growing season.
“My colleagues and I created a new model based off what we found in the literature,”

It appears several of the above posters were utterly confused about what the author(s) of the study actually meant via the statement of …. “created a new model”.
The author(s) simply changed one (1) of the “input” parameters (criteria) to the per se “computer modeling program” …. which resulted in a new “grain growth model” being generated (output) by the computer program.
I personally think that was a prime example of great scientific research.

asybot

Total growing degree days have been used in our grape growing area for at least 30 years if not longer. Just to decide if a piece of property has the right microclimate for grapes or any soft fruits ( of course soils etc are factors as well including the price of real estate.) I found this article only valuable in the sense somebody actually noticed it.
There might be hope yet.

Bruce Cobb

Climate change may be responsible for the abrupt collapse of civilization on the fringes of the Tibetan Plateau around 2000 B.C.

They just can’t bring themselves to say “global cooling”, can they?

joelobryan

They do say at the beginning of this press release:

that cooling global temperatures at the end of the Holocene Climatic Optimum, a 4,000 year period of warm weather, would have made it impossible …

We just don’t know how much of that Region’s current warm-up happened before 1950. My guess is the majority of it occurred before 1960.

Katherine

“My colleagues and I created a new model based off what we found in the literature,” Guedes said. “It revealed that global cooling would have made it impossible to grow millet in the Eastern Tibetan Highlands at this time but would have been amenable to growing wheat and barley. Our work turned over previous assumptions and explained why millet is no longer a staple crop in the area after 2000 BCE.”
You need to read more carefully. “Global cooling” is right there—and in a direct quote no less.

Climate change may be responsible

No intention of reading any further. The words “may be respponsible,” tells me that reading the article, is a total waste of my time.

Bohdan Burban

… “may be responsible” … pick the weasel-word

Admad

Lots of things “may” have caused something bad to happen. It’s Even Worse Than We Thought (TM), The Science Is Settled (c), Our Model Proves It (TM).

This might explain the observation that there are no budgies in Tibet. Yes, AGW decimates every species eventually!

Bohdan Burban

Or were they taken out by the budgie smugglers?

From Forbes, last year:
“The era that followed is known as the first Dark Ages, during which the thriving economy and cultures of the late second millennium B.C. suddenly ceased to exist. It took decades, and even hundreds of years in some areas, for the people in these regions to rebuild.”
Yes, as the Earth cooled, these ancient civilizations were punished by crop failures and famine.

And then we have the second dark ages and the root reason that Americans are primarily beer drinkers, …. to wit:

Western Europe experienced a general cooling of the climate between the years 1150 and 1460 and a very cold climate between 1560 and 1850 that brought dire consequences to its peoples. The colder weather impacted agriculture, health, economics, social strife, emigration, and even art and literature. Increased glaciation and storms also had a devastating affect on those that lived near glaciers and the sea.
Read more @ http://www2.sunysuffolk.edu/mandias/lia/little_ice_age.html

joelobryan

“There are some areas in the southeastern plateau where temperatures are 6 degrees Celsius higher than they were 200 years ago.”

Which what part of that warming was post-1950 when the IPCC says anthropogenic CO2 was sufficient to begin altering climate?

more soylent green!

Climate changes all the time, so why not? I think this bolsters the skeptical argument.

rogerthesurf

“Climate change ‘may’ be responsible for the abrupt collapse of Tibetan civilization around 2000BC”
Right and the change was anthropogenic right? Too much itinerant sword sharpening maybe?
Someone has forgotten that the perceived problem is that humans are causing the current natural climate change.
Cheers
Roger
http;//www.rogerfromnewzealand.com

BunkerHill Jim

Go Cougars … only 4 years to go …

BunkerHill Jim

4 K years ! I’ve fat old guy fingers !

BunkerHill Jim

But, via Al G. it could only be 4 years ….

High Treason

Shows what a meaningless term “climate change” is. Back then, it was certainly not man-made, was it. Of course, climate change is getting warmer OR getting cooler-a bet each way. wake up world, this is propaganda if there ever was. That such junk science is even written should be getting everyone deeply suspicious.

Chris Wright

I’ll give them some credit. Quite frequently, when research suggests that something bad happened because of a change in the temperature, they simply refer to it as “climate change”, probably because to acknowledge that bad things happened because of climate cooling is too inconvenient. The term “climate change” is great because it is so vague and can hide the simple fact that global warming is beneficial and global cooling is very, very bad for mankind and his civilisations.
But of course it all goes to pot when they feel they have to renew their vows to the climate change religion.
I find it difficult to believe that a region is now 6 whole degrees warmer compared to 200 years ago.
Still, ignoring the inevitable nonsense, this research does confirm the simple truth: warming is good, cooling is very, very bad.
Chris

Tim
tadchem

There is a lesson here on the risks of monoculture.