Andrew Revkin writes:
Michael Mann can’t be happy about this work.
Here’s a chat with two authors of an important new Science paper examining 10,000 years of layered fossil plankton in the western Pacific Ocean. The paper finds that several significant past climate ups and downs — including the medieval warm period and little ice age — were global in scope, challenging some previous conclusions that these were fairly limited Northern Hemisphere phenomena.
(video follows, an interview with authors)
The study finds that the rise in ocean temperatures in recent decades is far faster than anything seen earlier in the Holocene, the period since the end of the last ice age. But the researchers say that this rise is from a relatively cool baseline. Between 10,000 and 8,000 years ago, at depths between 500 and 1,000 meters, the Pacific Ocean was 2 degrees Celsius (3.6 degrees Fahrenheit) warmer than today. (text from the video description)
The paper is here:
http://www.sciencemag.org/content/342/6158/617
Pacific Ocean Heat Content During the Past 10,000 Years
Yair Rosenthal, Braddock K. Linsley, Delia W. Oppo
Abstract:
Observed increases in ocean heat content (OHC) and temperature are robust indicators of global warming during the past several decades. We used high-resolution proxy records from sediment cores to extend these observations in the Pacific 10,000 years beyond the instrumental record. We show that water masses linked to North Pacific and Antarctic intermediate waters were warmer by 2.1 ± 0.4°C and 1.5 ± 0.4°C, respectively, during the middle Holocene Thermal Maximum than over the past century. Both water masses were ~0.9°C warmer during the Medieval Warm period than during the Little Ice Age and ~0.65° warmer than in recent decades. Although documented changes in global surface temperatures during the Holocene and Common era are relatively small, the concomitant changes in OHC are large.
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from one ocean basin they jump to global conclusions.
what would folks say if the sediments showed the opposite
so we have a change in temperature….for centuries…that was a local event
…who was stupid enough to believe that in the first place
Given the location of the cores could it be that large ENSO events would be recorded? They did admit they only had decadal resolution. Darn paywall means I can only speculate.
Wondering if Bob Tisdale has a thought on this?
@Steve Mosher “what would folks say if the sediments showed the opposite”
Why not try asking Professor Mann? He knows all about inverted sediments..
They claim that a 1000m depth in the tropical latitudes imply that when it changes rapidly that it must have been global. Suspect it is based on a mixing model involving currents in both the north pacific as well as the south pacific. Perhaps reading the paper will clear that up @SteveM.
Mann understands well enough how devastating this might be for him. So, as fast as lightening, he’s out with quite a ridiculous response in Huffington Post.
http://www.huffingtonpost.com/michael-e-mann/pacific-ocean-warming-at-_b_4179583.html
One funny thing is that his headline reads “Pacific Ocean Warming at Fastest Rate in 10,000 Years”. So the main take-away message where there is no doubt for him is the only thing that in the interview the authors clearly said they can not really be certain about. All the rest he finds BAD BAD BAD. And almost all of the refuting, of course, comes from “Mann”, “Mann et al”, realclimate (Mann), “Mann and Jones” and so on. What narcissism…
This has been suggested by several earlier studies. Oppo’s 2009 reconstruction of the Pacific Warm Pool suggested the Medieval warm period was at least as warm as today.ReadOppo. D., et al., (2009) 2,000-year-long temperature and hydrology reconstructions from the Indo-Pacific warm pool. Nature, vol. 460, p.1113-1116.
Esper’s reconstrcution of Scandinavian tree rings also showed that the Roman period was warmer than the Medieval Warm Period which was warmer than the 1940s which was warmer than today. http://landscapesandcycles.net/image/75158734_scaled_586x204.png
And Esper’s tree rings agreed with local instrumental data that was not tainted by urbanization and data homogenization. Mann’s hockey stick relied on essentially calling tree rings deniers that diverged from his homogenized data set.
The truth is out there! And it is slowly coming into view.
With strong written evidence for MWP in Europe and East Asia (the main places they were writing stuff down) I rather guessed it might be global. Next we’ll be told it wasn’t a constant and regular warming. Sounds just like our Modern Warming, doesn’t it?
Anyone notice some strenuous attempts lately to bring back that hockey stick in its pristine 1990s glory? What next? Ban the Icelandic Sagas from school libraries like they banned Noddy? Snorri Sturluson to go the way of Enid Blyton?
Steven Mosher says:
October 31, 2013 at 1:21 pm
You don’t get it. CACA advocates have tried to argue that the Medieval Warm Period was restricted to the North Atlantic region. Study after study from around the world has shown this to be a bald-faced lie. Now the western Pacific has been added to that long list.
Besides which, the site surveyed also samples water masses linked to North Pacific & Antarctic intermediate waters.
But please by all means try to support a regional, not global Medieval Warm Period if you think that you can. I’ve observed its signs in southern South America myself, so you’ll have a hard sell.
My apologies to the original author, as I neglected to note their name or bookmark it:
One Tree to rule them all,
One Tree to warm them,
One Tree to graph them all
and in Global Warming bind them.
Mann’s Yamal tree still trumps the mountains of evidence from the rest of the world. In his own mind.
Some years ago, Dr Willie Soon, and Dr Sally Baliunas wrote a paper that was a review of many papers and reports from worldwide that showed that the MWP and the LIA were global phenomena, and not local peculiarities.
On the other hand, I believe if you look at the ORIGINAL presentation of Michael Mann’s hockey stick graph, which was in one of the IPCC reports, it states quite clearly on that graph that it is Northern Hemisphere only. In other words, Mann’s hockey stick was given to us as a local curiosity; not a global phenomenon. Of course, later expurgatory episodes, removed those limiting words, to hide the truth.
Mosher: “from one ocean basin they jump to global conclusions.”
A pretty big ocean. 46% of the Earth’s water surface. And one that spans both hemispheres.
Who’s the editor of Science? High time to get him sacked!
We’ll probably find out more from the eventual Climategate 2014 mails. If “the cooch” will not succeed before that…
Do we still have to get rid of the Medieval Warm Period?
http://stevengoddard.wordpress.com/2011/05/11/“we-have-to-get-rid-of-the-medieval-warm-period-”/
Mosher: “from one ocean basin they jump to global conclusions.”
As I understand it, the logic was that NH medieval warm period and little ice age were already agreed upon, though recently declared just regional by Mann and the Team. Now they found the same thing in the SH. So that’s the reason for “global conclusions”.
@omnologos: “far faster? what temporal resolution did they manage to get, in the Holocene?”
Your comment proposes a test:
How must faster is now, than the rest?
Did they slice the cores fine?
How precise is their line?
“Century-scale resolution, at best”
— (at 4:00 in the video)
The presumption that this claims to “show”?
They are stating here: They cannot know.
But they quickly recover, at last:
“Recent warming is very, very fast!”
But they’re fuzzy on just how they’re sure
Andy Revkin gave up. It’s obscure…
They like Marcott! And they complement it
And they compliment. They might regret it.
They admit other parts may be cooling
“Need more data!” (That’s always the ruling.)
They’d like to talk to ocean scientists
(And they haven’t yet? One gap that still exists…)
===|==============/ Keith DeHavelle
Steven Mosher says:
October 31, 2013 at 1:21 pm
from one ocean basin they jump to global conclusions.
what would folks say if the sediments showed the opposite
Everyone knows the Pacific has no effect on the rest of the world.
It’s about time real science caught up and with sediment cores. Now move the drill ship to the Atlantic.
Steven Mosher says:
October 31, 2013 at 1:21 pm
from one ocean basin they jump to global conclusions.
what would folks say if the sediments showed the opposite
That “ocean basin” occupies nearly half the globe. You would be mistaken if you did not draw global implications.
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And, if I’m not mistaken, Mann even got that wrong.
http://wattsupwiththat.com/2013/10/31/new-paper-shows-medieval-warm-period-was-global-in-scope/#comment-1462643
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To clarify, the “warmth” wasn’t even local.
(Sometimes we say things that, in retrospect, can be taken two ways.)
Since Dana Nuttercelli insists the ‘missing heat’ went into the oceans and that it’s a robust measure of global warming I wonder what he has to say about the oceans now?
Mann has posted a detailed commentary on the paper here: http://www.huffingtonpost.com/michael-e-mann/pacific-ocean-warming-at-_b_4179583.html
@ur momisugly Lance Wallace — THANK YOU (at 1:21pm today) for so generously sharing with the rest of us.
A Lance for Truth and Liberty!
Do you mean like Yamal?
And what would you have said had it had come to opposite conclusions?