Sorry no graphics, no abstract or paper (not published yet, due Friday the 27th, I hate it when they do this) the Penn State press release was rather spartan. So I’ll provide this one showing Mann’s previous work where the Medieval Warm Period doesn’t much show up at all:
So here’s the question, the press release below mentions sediments. Place your bets now on whether the Tiljander sediment series remains inverted or not. (h/t to Leif Svalgaard) – Anthony
Past regional cold and warm periods linked to natural climate drivers
Intervals of regional warmth and cold in the past are linked to the El Niño phenomenon and the so-called “North Atlantic Oscillation” in the Northern hemisphere’s jet stream, according to a team of climate scientists. These linkages may be important in assessing the regional effects of future climate change.
“Studying the past can potentially inform our understanding of what the future may hold,” said Michael Mann, Professor of meteorology, Penn State.
Mann stresses that an understanding of how past natural changes have influenced phenomena such as El Niño, can perhaps help to resolve current disparities between state-of the-art climate models regarding how human-caused climate change may impact this key climate pattern.
Mann and his team used a network of diverse climate proxies such as tree ring samples, ice cores, coral and sediments to reconstruct spatial patterns of ocean and land surface temperature over the past 1500 years. They found that the patterns of temperature change show dynamic connections to natural phenomena such as El Niño. They report their findings in today’s issue (Nov. 27) of Science.
Mann and his colleagues reproduced the relatively cool interval from the 1400s to the 1800s known as the “Little Ice Age” and the relatively mild conditions of the 900s to 1300s sometimes termed the “Medieval Warm Period.”
“However, these terms can be misleading,” said Mann. “Though the medieval period appears modestly warmer globally in comparison with the later centuries of the Little Ice Age, some key regions were in fact colder. For this reason, we prefer to use ‘Medieval Climate Anomaly’ to underscore that, while there were significant climate anomalies at the time, they were highly variable from region to region.”
The researchers found that 1,000 years ago, regions such as southern Greenland may have been as warm as today. However, a very large area covering much of the tropical Pacific was unusually cold at the same time, suggesting the cold La Niña phase of the El Niño phenomenon.
This regional cooling offset relative warmth in other locations, helping to explain previous observations that the globe and Northern hemisphere on average were not as warm as they are today.
Comparisons between the reconstructed temperature patterns and the results of theoretical climate model simulations suggest an important role for natural drivers of climate such as volcanoes and changes in solar output in explaining the past changes. The warmer conditions of the medieval era were tied to higher solar output and few volcanic eruptions, while the cooler conditions of the Little Ice Age resulted from lower solar output and frequent explosive volcanic eruptions.
These drivers had an even more important, though subtle, influence on regional temperature patterns through their impact on climate phenomena such as El Niño and the North Atlantic Oscillation. The modest increase in solar output during medieval times appears to have favored the tendency for the positive phase of the NAO associated with a more northerly jet stream over the North Atlantic. This brought greater warmth in winter to the North Atlantic and Eurasia. A tendency toward the opposite negative NAO phase helps to explain the enhanced winter cooling over a large part of Eurasia during the later Little Ice Age period.
The researchers also found that the model simulations failed to reproduce the medieval La Nina pattern seen in the temperature reconstructions. Other climate models focused more specifically on the mechanisms of El Niño do however reproduce that pattern. Those models favor the “Thermostat” mechanism, where the tropical Pacific counter-intuitively tends to the cold La Niña phase during periods of increased heating, such as provided by the increase in solar output and quiescent volcanism of the medieval era.
The researchers note that, if the thermostat response holds for the future human-caused climate change, it could have profound impacts on particular regions. It would, for example, make the projected tendency for increased drought in the Southwestern U.S. worse.
Other researchers on the project were Zhihua Zhang, former postdoctoral fellow in meteorology now at the National Oceanic and Atmospheric Administration; Scott Rutherford, Roger Williams University; Raymond S. Bradley, University of Massachusetts; Malcolm K. Hughes and Fenbiao Ni, University of Arizona; Drew Shindell and Greg Faluvegi, NASA Goddard Institute for Space Studies, and Caspar Ammann, National Center for Atmospheric Research.
The National Science Foundation, the U.S. Department of Energy, NOAA, and NASA supported this work.
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I have also found google to be a very biased site like Wiki. Me thinks Google should do some Googling.
I’m glad Mr. Mann has come round to the consensus view, will he now become a realist?
One day on the road to Damascus…….. .
This is rather good for the decision tree spoofs
http://www.devilskitchen.me.uk/2009/11/crudgate-why-this-cant-be-swept-under.html
The financial impacts of the ClimateGate scandal will be discussed in a special segment tomorrow (Sat. 11/28 ) on Fox Business Block (The Cost of Freedom ) on Fox News beginning at 10am ET. Should be interesting to hear what they say the potential market fallout from all this might be, although it seems fairly obvious. If it hurts the money guys, you can bet they will be the first to grab a shovel and bury AGW.
As has been said in another context: “Follow the money”.
@ur momisugly Jason – Tim and Judi did an excellent article that you referenced.
We already knew about the MWP and the LIA… so why the fuss over a “formerly reputable?” scientist named Mann – infamous for Mann made global warming – why give the guy any press – he is a fraud and should be in jail why we sort this out.
This is going to shake the trust of the world – unless we clean house now!
What if all congressmen take a real Hockey Stick with them to your congress when discussing C&T?
A surprisingly open-minded, even eirenic column by Andy Revkin today, featuring Judy Curry, who posted in the past few days, on Climate Audit.
http://dotearth.blogs.nytimes.com/2009/11/27/a-climate-scientist-on-climate-skeptics/?hp
A must read.
Sorry, but this is garbage…claiming ENSO was always La Nina until very recently defies the Gods of history. The Incas beg to differ…they seemeed to be well acquainted with the 3-7 year ENSO cycle I learned about in school.
In this PR two-step we are seeing quite a bit of the “After Breakdown UEACRU Swoon Effect” science (ABUSE SCIENCE) with Mann spinning away from the heat somewhat. By admitting a slight” MWP and gently cooling LIA he is beginning the dance to adjust as seamlessly as possible toward a more tenable position. He’s scared sick of the wave of FOI requests that must surely be about to swamp all these fortified institutions. He has all his friends in the et al to save their arses, too.
No, it is not on the list. Even after you put in the full “climategate”, it has “Climate Guatemala” and “Climate Guatemala City” under it.
“Past climate anomalies explained”
“We reconstructed patterns of [the Earth’s] surface temperature during those two intervals,” explained Professor Michael Mann from Pennsylvania State University in the US, who led the study. ”
http://news.bbc.co.uk/1/hi/sci/tech/8381317.stm
“and suggest that that when you heat the Earth’s surface, the climate system tries to offset and cool”
“that the Earth’s response to greenhouse-gas-induced global warming might be more complex than “natural” warming.”
No thermageddon??? I may not have understood the BBC article, but is someone looking for an escape route. Is it Mann or the BBC?????
Corey wrote: No, it is not on the list. Even after you put in the full “climategate”, it has “Climate Guatemala” and “Climate Guatemala City” under it.
Thanks! Now we need to find a way to prove that it was there yesterday. I’m doing some research on that right now. I sent the story to Newsbusters.org and Noel Sheppard already responded.
On the upside – the normal Google algorithm is working correctly. It already picked up my post on the telegraph (written 2 hours ago) when you search for google climategate autosuggest. They would have to destroy their entire system to hide this story. 🙂
royfomr (05:42:19) :
Just a wicked, wee thought.
I just googled “Google ClimateGate”, the quotes are essential, and got 223 results
Try just “Climategate” Results 1 – 10 of about 10,200,000 for climategate. (0.39 seconds)
Anthony, I know we have not seen eye to eye but please let these posts run.
I have no selfish reasons for posting here, my only aim is to kill Copenhagen.
[snip]
REPLY: “Sophistry in politics” No and hell no. You proceeded to post bomb multiple threads here multiple times even after I told you the content you were pushing on your website was not welcome.
Hell you are doing it right now, multiple posts under difference names.
Coming back later and saying “we have not seen eye to eye” while at the same time engaging in post bombing time insults my intelligence and the intelligence of readers here when what was called for was an apology.
Bugger off!
– Anthony
Endless publicly funded climate research by meteorologists such as M Mann is definitely not the way to go. The work will go on for decades and decades producing guff. As the specific target of the warmists is a massive reduction in CO2 emissions the research should be directed at the physics of CO2 long wave radiation absorption. The absorption bands for CO2 are non existent between 7 and 13 microns allowing 70 to 90% of the radiation from earth to escape to space. This would be true even for a doubling of CO2 from 350 to 700ppm.This micron range is called ‘open window radiation’ where the greatest portion of radiation emitted by the earth is found.
It could be clearly established that it is impossible for CO2 to cause global warming and the warmists view that the spectral band 12 to 18 microns includes the peak emission of the Earth’s spectrum thoroughly discredited. Wien’s law shows that a wavelength of maximal emission λmax of 15μm yields a temperature of minus 80C; whilst 15C gives a maximal emission λmax of 10μm.
P Gosselin (00:46:35) : BBC debate.
Mann’s publication and further discussion of the science of climate is moot in the face of malfeasance. The debate at this point cannot go back in time before we knew of East Anglia. We know. We know more every day. And the more we know the more we see that Jones, Mann, and CRU cronies worked actively to kill even-handed research and debate.
Now, we must address the issue of the climate elite manipulating, deleting and hiding data that SHOULD have been included in debate. The science cannot resume until we have addressed the issues of malfeasance. The only agreement at Copenhagen if the junketeers insist on convening – is to throw open wide the doors of investigation. Establish an fully independent international investigatory committee to look NOT at the means of the leak – but the CONTENT of the leak.
Any discussion of caps and emissions now is hogwash. The people of Earth want to know why their “experts” and “media” and “governments” have been complicit in the greatest fraud perpetrated on mankind since Eden’s snake whispered to Eve. It is epic.
And CB DeMille is itching for a comeback.
See above cmment R Stevenson (10:31:13)
Roger Sowell (07:46:25) :
“Meanwhile, back in the real world where actual measurements exist, we are getting more of that “projected US Southwest drought” tonight and this weekend. About 4 to 7 inches of white “drought” plus rain (oops, can’t say that word, can we?) are forecast to fall across Kern County (Bakersfield and surrounding areas) in Southern California. Seems a cold weather front is pushing through.
Hmmm…and northern California, Oregon, and Washington just got pounded with rain and snow.
(Say, Anthony – how about we change the label for the Mann et al team to “liars?”) We’re the skeptics, they’re the liars. Just a thought. (I know, I know…Liars is too inflammatory and combative…need something softer but accurate)”
I think most climate scientists get so used to dealing with global averages that they forget that what we experience of climate is local and it is here we fnd the extremes. The rich tapestry of turbulence and boundary condition effects are what real climate is about. These events are the nuts and bolts of the excess energy removal systems whch regulates the Earth so well, as is demonstrated in Mann’s graph.
So there are no long-term trends or any chance of accurate future forecasts beyond a few days, just chotic climate happening on a second by second basis.
Regarding CRU et al, perhaps a kinder term than ‘liars’ would be bender – appropriate, perhaps, because of their propensity to manufacture hockey sticks.
How can anyone know with any reliability what was weather/climate in Pacific in medieval period? We certainly know if it was glacial or not but besides that what is the error margin?
This is really not so out of topic, and hilarious.
[Snip. Sorry annav, but it’s been decided that one’s a bit over the top. Not that I didn’t get a chuckle out of it, but it does sort of cross the line. ~ Evan]
Another possible aspect/set up from Mann’s latest paper… in some of the leaked emails a bunch of them were discussing problems with being able to forecast regional variations and I believe mentioned getting pressure from politico’s for better regional casts.
Seems that this latest paper, in hitting on a supposed regional only MWP, works to set up the prospects for greater research and funding into regional forecasting. Perhaps just another way to pave a path forward for ‘the team’ to continue to get large grants.
Gee, now that the science is settled in terms of global warming (even if we have a little bit of tweaking here and there, well, that’s just to be expected), now its time to turn to the fine tuning so we can help ALL of you with what each of your regions can expect for the future!
@Dave (08:25:11) :-SNIP- Also a leading BBC weather journo has been found to have been sitting on the infamous hacked E-mails for six weeks and said nothing.
The BBC is a publicly funded organisation.
—————–
Doesn’t that mean that they are also subject to FOI requests? If so, might be quite interesting if a request is made for ALL BBC correspondence, emails, memo’s, documents related to the hacked/leaked CRU information from the minute it was received up until the day it went public.
I’m assuming that FOI’s can only come from citizens, not from those of us in other nations? Is that correct?
P Gosselin (00:46:35) :
Reference: Debate!! Yes, on the BBC!
At 7:30 in the BBC interview, Dr. Watson is asked why the data haven’t been released. Essentially, he answers that the data are owned by the various National Meteorlogical Services, and therefore, it is not proper for the UEA CRU to release the data.
I would like to ask Dr. Watson a question, and depending on his answer a series of follow-up questions:
(1) Has UEA CRU released any meteorological data not owned by UEA CRU to any organization(s)?
If his answer is yes, then
(2) Which organizations and which data?
(3) Did UEA CRU have permission to release such data?
(4) If yes (to 3), could we see documentaion of such permission?
(5) If no (to 3), can you explain the criteria by which the UEA CRU makes the decision to illegally (at least according to Dr. Watson) release the data to a requesting organization?
Somehow I believe a cross-examination by a competent lawyer would soon have Dr. Watson wishing he had never participated in the interview.
cynical bastard (08:36:15) :
Kate @ur momisugly 02:14:42 – it is not from The Onion, I hope?
No, it’s from eyewitnesses.
The Polynesians were colonizing the Pacific 1000 years before they arrived in New Zealand in 1300. They traveled in large ocean-going canoes (waka), which were somewhat storm sensitive. Now there was obviously a lot of trans-island travel in the jumping off point, and they must have been fine seamen to make colonizing ships. They also must have had an idea where they were going. It seems obvious that the Pacific was not very stormy in this period.