The Medieval Warm Period linked to the success of Machu Picchu, Inca Empire

According to Wikipedia,  the Medieval Warm Period was a time of warm weather around AD 800-1300 during the European Medieval period. Initial research on the MWP and the following Little Ice Age (LIA) was largely done in Europe, where the phenomenon was most obvious and clearly documented. It was initially believed that the temperature changes were global. However, this view has been questioned; the 2001 IPCC report summarises this research, saying

“…current evidence does not support globally synchronous periods of anomalous cold or warmth over this time frame, and the conventional terms of ‘Little Ice Age’ and ‘Medieval Warm Period’ appear to have limited utility in describing trends in hemispheric or global mean temperature changes in past centuries”.

Of course, there’s many researchers, such as Michael Mann and his thoroughly discredited “hockey stick”  that  try mightily to make the MWP disappear.

MWP-hockey-warming_graph

News flash to IPCC.  Now a scientist has linked the MWP to success of the Inca civilization in the southern hemisphere. It is not going away any time soon, it is spreading.

The new study is called “Putting the Rise of the Inca within a Climatic and Land Management Context” and was prepared by Alex Chepstow-Lusty, an English paleo-biologist working for the French Institute of Andean Studies, in Lima. Link to paper (PDF) is here (h/t to WUWT reader Corey)

Here is the abstract:

The rapid expansion of the Inca from the Cuzco area of highland Peru produced the largest empire in the New World between ca. AD 1400–1532. Although this meteoric rise may in part be due to the adoption of innovative societal strategies, supported by a large labour  force and standing army, we argue that this would not have been possible without increased crop productivity, which was linked to more favourable climatic conditions. A multi-proxy, high-resolution 1200-year lake sediment record was analysed at Marcacocha, 12 km north of Ollantaytambo, in the heartland of the Inca Empire. This record reveals a period of sustained aridity that began from AD 880,  followed by increased warming from AD 1100 that lasted beyond the arrival of the Spanish in AD 1532. These increasingly warmer conditions allowed the Inca and their predecessors the opportunity to exploit higher altitudes from AD 1150, by constructing agricultural terraces that employed glacial-fed irrigation, in combination with deliberate agroforestry techniques. There may be some important lessons to be learnt today from these strategies for sustainable rural development in the Andes in the light of future climate uncertainty.

Here is a news article about it that talks of the findings. (h/t to WUWT reader “cotwome”) – Anthony

Huayna Picchu towers above the ruins of Machu Picchu

Opportunity knocks, again, in the Andes

by Nicholas Asheshov
The last time global warming came to the Andes it produced the Inca Empire.  A team of English and U.S. scientists has analyzed pollen, seeds and isotopes in core samples taken from the deep mud of a small lake not far from Machu Picchu and their report says that “the success of the Inca was underpinned by a period of warming that lasted more than four centuries.”

The four centuries coincided directly with the rise of this startling, hyper-productive culture that at its zenith was bigger than the Ming Dynasty China and the Ottoman Emachu_picchu_globempire, the two most powerful contemporaries of the Inca.

“This period of increased temperatures,” the scientists say, “allowed the Inca and their predecessors to expand, from AD 1150 onwards, their agricultural zones by moving up the mountains to build a massive system of terraces fed frequently by glacial water, as well as planting trees to reduce erosion and increase soil fertility.

“They re-created the landscape and produced the huge surpluses of maize, potatoes, quinua and other crops that freed a rapidly growing population to build roads, scores of palaces like Machu Picchu and in particular the development of a large standing army.”

No World Bank, no NGOs.

The new study is called “Putting the Rise of the Inca within a Climatic and Land Management Context” and was prepared by Alex Chepstow-Lusty, an English paleo-biologist working for the French Institute of Andean Studies, in Lima.  Alex led a team that includes Brian Bauer, of the University of Illinois, one of today’s top Inca-ologists. The study is being published in Climate of the Past, an online academic journal.

Alex spends a lot of time in Cuzco and he told me the other day that the report “raises the question of whether today’s global warming may be another opportunity for the Andes.”

The core samples from the sediment of the little lake, Marcacocha, in the Patakancha valley above Ollantaytambo, show that there was a major cold drought in the southern Andes beginning in 880 AD lasting for a devastating century-plus through into 1000AD.  This cold snap finished off both the Wari and the Tiahuanaco cultures which had between them dominated the southern Andes for more than a millenium.

It was at this same time that the Classic Maya disappeared in Yucatan. It was also a time, on the other side of the Pacific when major migrations from East Asia took place into Polynesia, an indication of a major Niño event; a Niño sees western Pacific currents switch to flow from West to East.

Core samples from glaciers and from the mud beneath lakes in the Andes, the Amazon and elsewhere have built up a history of the world’s climate and the message is crystal clear. It is that changes have taken place in the past, during the six or seven thousand years of our agriculture-based civilizations, that are just as big as the ones we are facing from today’s CO2 warming.

The message may be, too, that climate change is especially forceful in the Andes. Here we are, sandwiched thinly between the world’s biggest ocean and the world’s biggest jungle. The peaks are so high that they have had until just a few years ago deep ice on or near the Equator.

The valleys and surrounding hills have formed the roof of the human world for at least three millennia, according to Alex Chepstow-Lusty’s core samples. Nowhere else do millions of people live at or even near 4,000ms above sea level where it is cold, but getting warmer.

Today’s warming is also following on a colder spell that started, the core samples say, not long after the arrival of the Spaniards in the 16th century.

For instance, the pollen in the cores says that there was maize being grown under the Incas around the lake at 3,300ms a.s.l. Until recently the upper level for maize around the Urubamba valley was 3,000-3,100ms. In the past few years the maize level has moved up and today there is maize being grown again above Marcacocha.

Alex’s records show that hundreds of terraces were being built around the lake between 1100 and 1150 AD -“lots of mud followed by the heavy pollen of maize.”

Enrique Mayer, at Yale, tells me that “the question of the expansion of maize together with the Inca state is now a proven archeological fact, notably in the Mantaro Valley (Tim Earle).

“The question of why terraces are not worked now as intensively as they could has been worked on (Bill Devevan) in the Colca Valley where the terraces are actually in franco retroceso.

“Also, you have John Treacy’s book on Coporaque which is probably the most technically accessible to the argument that terraces are, like flower pots, expensive to maintain.”

There is also, of course, the work of John Earls on the terracing at Moray.

Today there are thousands upon thousands of fine flights of Inca terraces all over the upper ends of the valleys of Central and Southern Peru but few of them are used on a regular basis.

Efforts have been made, among them by Ann Kendall, the English archaeologist, to rescusitate the old irrigation channels and the use of the terraces in the valleys above Machu Picchu. But most have been re-abandoned.

In the same vein the great forests of polylepis, the world’s highest tree, which capture and conserve moisture, have mostly been cut down for firewood.

As they say, you only have to look in the mirror to see where the problem is.

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theduke

Apart from the fact that it presumes CO2 to be the cause of today’s warming, this is a very informative piece.

Curiousgeorge

Every day we hear of yet another piece of evidence that gives the lie to the IPCC et al , and the currently popular ( among politicians at least ) anthropogenic climate change conjecture. How much hard evidence, such as this, is it going to require to overcome the momentum this conjecture has built up over the last few years?

noaaprogrammer

…and don’t forget the rise & fall of cliff dwellers in the Southwest – e.g. the Anastasi people.

Chris Schoneveld

Alex Chepstow-Lusty’s work is just one of many studies that have confirmed the existence of the MWP in the SH.
http://www.co2science.org/subject/s/southamericamwp.php

Slide2112

Ah, so it was the Inca who caused the MWP…

Jon P

RealClimate (you know where where “real” climate scientists post, will analyze and comment on this paper in 3-2-1…..never…..

Evan Jones

fall of cliff dwellers
I can see how that would be a problem.

Steve Keohane

Anyone who follows paleo-anthopology knows that climate reconstructions are done at a lots of digs. Pollen, plant remnants and insects provide onfo on living conditions for the inhabitants. If you look at this for 40 years or so, you develop a feel for the natural variance of climate. This is why ten minutes in AIT, my wife shut it off, due to my ranting at Gore for showing time-truncated and outright fabricated temperatures for the past several centuries. Steve McIntyre validated my ascertions with analysis of Mann, Briffa, etc.

michel

Well, its just a matter of time before someone posts the argument that if the MWP existed, it is bad news for scepticism, because it will simply prove that the climate is more sensitive, not less, to CO2.
Quite how it is supposed to prove this has never been entirely clear. The proponents of the argument wisely avoid explaining.

Charlie

“RealClimate (you know where where “real” climate scientists post, will analyze and comment on this paper in 3-2-1…..never…..”
Let’s see which blogs reject this study since the authors aren’t climate scientists.
Facts are more “robust” than any theory. It may take a while, but facts do [u]generally[/u] win out.

Ric Locke

J. Christ on a pogo stick, can I get in on some of that grant action? I could sure use the money…
Show me a “lost city of ancient civilization” and there’s a huge chance it dates back to either the MWP or the Roman Warm. The Anasazi, as noaaprogrammer notes. Angkor Wat. Mapunguwe (in South Africa). The list goes on. Dangit, to the extent they can put dates on it, the Australian Aboriginal “Dream Time” matches! About the only negative version of that is Teotihuacan, which went away at about the beginning of the MWP — and that corresponds to the consolidation of Aztec culture and its subsequent rise.
Bah. It goes back to a question I’ve been asking since the beginning of the Gerbil Worming hysteria: What was the sea level in the Bay of Bengal in the year 1000?
Regards,
Ric

dkemp

Dr. Soon from Harvard published an article maybe 5-6 years ago, which contained no new work of his own but, instead contained a fairly long list of articles focusing on the LIA from authors around the earth. Dr. Soon’s article showed pretty clearly that from these other papers the LIA was a worldwide event and not just a US or European event. I think Dr. Mann shortly thereafter suggested, before Congress no less, that Dr. Soon shouldn’t be allowed to publish any more.

John Anderson

I suspect that the title would read better were it:
The success of Machu Picchu, Inca Empire linked to the Medieval Warm Period.
The original phrasing could lead some to believe the Incans caused the MWP, much as they think we are causing AGW today.
Sure, it sounds crazy, but so does AGW.

Paul Nikkel

Anthony:
What is the source for the bottom graph that you show below the Mann “Hockey Stick” in the introduction?

Ron de Haan

Interesting article.
Unfortunately all the debunked subjects keep on coming back in print and television broadcasts over and over again. It is a tiresome process.
Fortunately the MSN is punished severely.
People stop reading the papers, they stop watching stations like BBC, CNBC CNN, Discovery Channel, and National Geographic Channel.
They turn to the internet and make up their own mind.
This is the effect of OVERKILL and BIASED REPORTING.
The cold weather is a great help too.
The public knows when they are tricked into a scam and we should have more faith in their judgment.

pinkisbrain

if you have a look at this good overview:
http://www.co2science.org/data/timemap/mwpmap.html
you will find in almost every region of the planet the MWP, the times, the anomalies and so on…
i have no idea why m. mann could ever public his hockey stick and why an IPCC did so.

Patrick Davis

I understand The Moche existed before the Incas in, what is now, Peru between 100-800AD and their fall has been attributed to climate change. They already lived in quite a harsh environment, and when the climate changed, crops failed, it rained heavily, animals starved, they then started sacrificing humans (This has a familiar theme with today’s AGW crowd), when that didn’t “apese the God’s”, they, who were left, started fighting between themselves until, there were none.

Ray

Appart from that the author believes that today’s warming is from anthropogenic carbon dioxide, this article shows clearly that the temperature rise of that time period was global, and indirectly the following cold period. I still don’t really get it why the author still thinks that CO2 makes tmperatures go up? The record shows otherwise… and he does not say anything as to why it was warmer.

Douglas DC

Darn Inca and their SUV’s.Wait! you say they didn’t have the Wheel Ok they were tracked then! Believe!!

Steven Hill

shut up and pay the tax…….Barrack Obama has spoken

Austin

The Mongols expanded at the hight of the MWP.
The Hohokam culture collapsed at the end of the MWP during massive floods.
The Medieval Famine was in 1315-1317 and things did not stabilize until 1322. The Black Death followed in 1338.

Sam the Skeptic

I think the cliff-dwellers were actually Anasazi but I my be wrong. There is certainly evidence of a highly sophisticated culture (they changed their leaders according to the season!) which MAY have been unable to survive the LIA for reasons to do with over-population vs declining crop yields.
There is certainly enough evidence from elsewhere that the price of wheat varied in inverse proportion to the number of sunspots which adds to the argument that a) there was a medieval warm period — better yields=lower prices, and b) the climate then got colder — lower yields=higher prices.
I really have trouble working out why that is so hard for a scientist to understand, or at least include in the parameters of his research.

Besides, the MWP is validated by the records of iron stained grains, the same than the LIA. The percentages of sedimentary ISG are proportional to solar irradiance through a logarithmic function:
ISG% = |3362 [LN(TSI)]-24268|*1.94
For example, for a TSI of 1366 W/m^2, the proportion of ISG is 8.06%. The margins of error is -0.15 to + 0.15.
Taking into account a negative response to temperature, the MGW and LIA are beautifuly delineated when the ISG values are set in reverse order.
This formula is applied, of course, only for well known values of Total Solar Irradiance; for example, the satellite measurements of the intensity of TSI.

Conservative&denialist

This is quite interesting. Scafetta paper, presented at the EPA:Climate Change and Its Causes:A Discussion about Some Key Issues
Nicola Scafetta, Duke University
also talks about the same (slide #9).
There is something to add here: Up there in Macchu Picchu there is a sun dial stone called the “Inti watana”(from Inti=Sun and watana=which ties) to mark the solstice, however the Inca’s solstice holiday, the Inti-raymi or Sun’s holiday, is traditionally held in june 24th, so this holiday has 3 days back referred to the nowadays solstice june 21th; so if we take the difference in seconds we have 259200 seconds, that in turn divided by 52 arc seconds a year of equinoxes’ precession, we obtain the original date when this holiday was instituted is 4984.61 years back in the past. This is not surprising but only for those archeologists who do not have any knowledge of equinoxes precession. And this is not surprising because, near Lima City, the capital of Peru, it has been found an archeological site of that antiquity, Caral, built before the pyramids of egypt ( http://www.caralperu.gob.pe/nueva/principal.html ) where Quipus (pronounced “kee-poos” :Knot writing) have been found (Quipu was the first Inca writing, and, by the way, also the first writing taught by the first chinese terrestrial emperor Fu-Hi, as told by Walter A.Fairservis, in his book:The origins of Oriental Civilization-Mentor books collection, Ancient Civilizations)
It will be useful also to let you know that one of the main events in the Inti-Raymi conmemoration it is the lightning of a fire by using a concave mirror, so assuring that the sun is close enough to light it on.

Alan the Brit

Jon P;-)
Of course they’ll examine it but as “the duke” points out, it relies upon the presumption that CO2 is causing today’s apparently “unequivocal” warming!
Still, I bet it is an intersting read nevertheless, but it must leave some questions about today for some. Of course, it would a really good wheeze to change the colour schemes of those graphs, how about blue for hot & green for cold, that should confuse a few folks!
OT but Met Office is being very cautious about forecasting the remainder of the UK’s “sizzling summer” we’ve had a few days of. July supposed to be pretty awful – no change there then as it has always historically been a fairly wet month, August is supposed to get the “sizzle” apparently, will keep you posted! It must be a bit like gambling one is bound to win something eventually if you paly often enough but I fear they are on a hiding to nothing – again!

Near as I can tell, warmer weather is beneficial to life, plants and animals as well as humans.
Do we need any more proof that liberals are gripped with and motivated by cultural, societal and planetary suicide?
All life on earth is carbon based, viewing carbon as a “pollutant” and demanding its reduction and/or removal is nothing more than calling for extermination of all life. That is the end result of their programs and we need to see it for what it is.
It is time for a culture of life to assume control of the debate and the decisions.
Best regards,
Gail S
http://backyardfence.wordpress.com

Vincent

What’s wrong with these scientists? Don’t they know the MWP does not exist?
It’s all lies!

bill

What is amazing is that no-one will trust temperatures measured with instruments. Yet the headline graph shows temperatures to within 0.5degC back to times when temperatures were measured by hot, cold and ok!!
It is interesting to note that this temperature plot from an earlier blog entry
http://wattsupwiththat.files.wordpress.com/2009/07/kirkby_slide_siberianclimate.jpg
shows Siberian temperatures being 1degC below 20Century normals
And this plot of grape harvest date shows no shortened harvest times (compared to 2000+) Times (and so temperatures) are similar to those in 1650 to 1700
The LIA is missing from the grape dates as well – the plot at top shows LIA 1550 to 1700 but this period is similar to 1790 1900 in dates and therefore temperatures.
Life is so full of incosistencies!

SteveSadlov

No doubt the MWP was a world wide golden age for the emergence of mountain cultures. Alpenvolk, Tibettans, Mustangians, Nepalese, and the ones already mentioned. Then, when things got cold, they became scattered remnants. Their cultural oddities derive from that pattern of early development followed by a deep retreat and fall off in population.

Richard Heg

I linked to this article in a previous comment. This article is in the current national geographic about the city of ankor in cambodia. The city was at its hight around the 12th century at the hight of the warm period and fell due to lack of rain during the little ice age.
http://ngm.nationalgeographic.com/2009/07/angkor/stone-text

SteveSadlov

Argh … MWP.
REPLY: Fixed pre-argh, Anthony

Don S.

noaaprogrammer
Not sure who the Anastasi were. Google might ask “did you mean Anasazi?”
Sam the Sceptic
‘The Mayor of Casterbridge’ is a fine literary exposition on the effect of climate on wheat prices. Because of the way farm products were marketed in England, knowledge of weather precursors were avidly sought and drove the futures sales of grains. Still do. Want to know what the weather will be in East Anglia next fall? Ask a farmer. He’s betting his personal wealth on it.

Corey

Here is the study:
Putting the rise of the Inca Empire within a climatic and land management context
Received: 30 January 2009 – Accepted: 2 February 2009 – Published: 4 March 2009
Abstract
The rapid expansion of the Inca from the Cuzco area of highland Peru produced the largest empire in the New World between ca. AD 1400–1532. Although this meteoric rise may in part be due to the adoption of innovative societal strategies, supported by a large labour force and standing army, we argue that this would not have been possible without increased crop productivity, which was linked to more favourable climatic conditions. A multi-proxy, high-resolution 1200-year lake sediment record was analysed at Marcacocha, 12 km north of Ollantaytambo, in the heartland of the Inca Empire. This record reveals a period of sustained aridity that began from AD 880, followed by increased warming from AD 1100 that lasted beyond the arrival of the Spanish in AD 1532. These increasingly warmer conditions allowed the Inca and their predecessors the opportunity to exploit higher altitudes from AD 1150, by constructing agricultural terraces that employed glacial-fed irrigation, in combination with deliberate agroforestry techniques. There may be some important lessons to be learnt today from these strategies for sustainable rural development in the Andes in the light of future climate uncertainty.
http://www.clim-past-discuss.net/5/771/2009/cpd-5-771-2009.pdf
REPLY: Thank you sincerely for finding that, I spent time looking but was unable to. – Anthony

Corey

REPLY: Thank you sincerely for finding that, I spent time looking but was unable to. – Anthony
You’re welcome! Keep up the good work.

Gail S (10:09:58) :
Near as I can tell, warmer weather is beneficial to life, plants and animals as well as humans.
And biologists are sure of it. I do not understand why some colleagues adhere to the fallacy on the “toxicity of the carbon dioxide pollutant”. They do know for sure that life is not possible without carbon dioxide. In the begining of life, living beings were chemosmotic-anoxibiotic organisms. Life prospered in environments with more than 8000 ppmV of CO2 (proterozoic era).
In the middle proterozoic chemoautotrophic organisms appeared and by the late proterozoic the composition of the atmosphere started changing. The proportion of Oxigen increased due to the release of this gas from H2O through photosynthesis. The superwarm Earth during the proterozoic era is evidence against the role of carbon dioxide like an important “greehouse” gas.

George Tobin

I think the Incas suddenly realized it really could not really be that warm and pleasant because the Medieval Warming Period (if it existed all all) was limited to northern Europe–and their economy collapsed as a result of that realization.
It may also be the case that when believers in Inti (the sun god) starting to perceive that the god Illapa’s extreme weather events were actually a form of positive rather than negative feedback that the religious culture was fatally undermined as well.
Also, there is no truth to the silly rumor that Pizarro ordered Atahuallpa, last of the Incan rulers to be executed with a hockey stick.

Conservative&denialist

Thanks to Mr.Nasif Nahle (11:25:05) : we can guess that perhaps some
chemosmotic-anoxibiotic organisms are the ones after the “global warming” issue. 🙂

Barry Foster

Can someone guide me in the right directions? In this month’s BBC Focus magazine (here in the UK) they say that the Medieval Warm Period wasn’t global. But is the current warming global? Are there many places which show no warming, or even cooling since 1979? I know the lower troposphere shows no warming now, and neither does the Antarctic, but are there any other places? Thanks.

Michael D Smith

Thanks for the link… The comment about CO2 warming is not in the linked paper.

Edward

I marvel at people who still deny that there was a medeival warm period. There’s ample evidence of earlier warmer periods when people traversed Alpine mountain passes that are now covered by glaciers. The Romans did so as did the “Iceman” Otzi about 5300 years ago. Perhaps our climate is just now returning to a more normal warmer time period. Please find link below.
Thanks
Ed
http://news.bbc.co.uk/2/hi/science/nature/7580294.stm

tj

Gail S., In answer to your question all “liberals” are not “…gripped with and motivated by cultural, societal and planetary suicide…” Liberals have been misinformed by the people they trust. The masses of them would change their minds immediately if they weren’t filled with total malarkey by their leadership and the media, which is almost totally owned and controlled by very wealthy “conservatives”. Don’t you smell the ruse? The people at the top, the ones who have orchestrated this issue , are neither liberal in the sense the average “left leaning” individual thinks or conservative in the way the average “right leaning” individual thinks. In fact those two groups, sans the misinformation, would think like honest Americans which both groups consider themselves to be. We agree on most things with slight differences in degree and which propaganda sources we believe. We are,however, intentionally fooled to believe we are enemies. The scam wouldn’t work without the divide and conquer technique used in many issues, not just this one.

Jim Papsdorf

I know it is only “weather” but things are getting a little colder in the SH these days:
Deadly Cold Wave Brings Misery to Southern Peru
08 Jul 2009 14:31:00 GMT
An intense cold front has brought heavy snow, hail, strong winds and unusually low temperatures to southern Peru where the deaths of more than 150 children have been blamed on the cold. The situation prompted the Peruvian government to declare a state of emergency in 21 regions of the country, said the Adventist Development and Relief Agency (ADRA).
http://www.alertnet.org/thenews/fromthefield/219487/124706360614.htm

sylvain

Now What, the MWP was limited to europe and the Inca empire but miraculously skipped the rest of the world.

Scott B

On the bottom graph, how is the line around 9.2C the 20th Century average temperature when the majority of the 20th century is above the average? Also, the positive temperature anomalies appear to be greater than the negative.

Jakers

The problem I have with this study is the time-line they have created. I’ve taken cores and worked up their stratigraphy, and taken C14 dates, and one has to be very careful about conclusions drawn from them. They don’t discuss how they determined the time periods much. “The chronology for the sequence was derived from six radiocarbon dates and seven 210Pb dates (Table 1).” OK – they got dates at AD280, AD630, and AD1360, and others outside that range, then they interpolated in between even though there was not a uniform deposition rate, to get 880, 1000, 1100, 1150, etc. In fact, looking at the site picture, deposition could easily have been pulsed from up slope erosion events.

Miles

Seems Al Gore has more than the Third Reich to battle.

Conservative&denialist (11:36:38) :
Thanks to Mr.Nasif Nahle (11:25:05) : we can guess that perhaps some
chemosmotic-anoxibiotic organisms are the ones after the “global warming” issue. 🙂

Heh! By the way, it should have said “oxygen”, not “oxigen”… Sorry. 🙂

KLA

Well, limestone caves exist all over the world.
This study:
http://www.worldclimatereport.com/index.php/2006/11/15/stalagmite-story/
Shows a temperature record derived from isotopic data preserved in limestone stalagmites from such caves for Europe. It seems to me that all one has to do is to correlate similar data from caves all over the world to settle the question wether the MVP or roman warm period were local or global.

Jim L

Frost warning for Eastern Canada. It’s July 8th for cryin’ out loud:
http://www.theweathernetwork.com/index.php?product=alerts&placecode=canf0253&region=wwcanl0027

Bruce Cobb

Hmmm… The Medieval Maximum, a time of high solar activity occurred then. Must be just coincidence, though. Then again, C02 levels historically have followed temperature rises by approximately 800 years, which is about how long ago the MWP was. So, the fact that today, some 800 years after a significant warming we have a rise in C02 must be just another coincidence. Because, nothing beats the power of manmade C02! Sarc/off.