UPDATE: McIntyre discovers a serious flaw right away, more upside down Mann world – he writes:
In keeping with the total and complete stubbornness of the paleoclimate community, they use the most famous series of Mann et al 2008: the contaminated Korttajarvi sediments, the problems with which are well known in skeptic blogs and which were reported in a comment at PNAS by Ross and I at the time. The original author, Mia Tiljander, warned against use of the modern portion of this data, as the sediments had been contaminated by modern bridgebuilding and farming. Although the defects of this series as a proxy are well known to readers of “skeptical” blogs, peer reviewers at Nature were obviously untroubled by the inclusion of this proxy in a temperature reconstruction.
More here: http://climateaudit.org/2013/04/11/more-from-the-junior-birdmen/
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‘Charles the Moderator’ writes to inform us that there’s another multiproxy study published, with flat blade and a somewhat limp hockey stick combined with that “unprecedented” claim that has become almost a red flag for bad proxy studies when they are that certain. From the SI PDF file, it looks like it is another splicing study, where they have added CRU data to the paleo reconstruction using tree ring, ice core, and varve data.
I have to wonder though, about the insensitivity of the proxies in the past, that blade seems pretty flat.
Of course it is paywalled, so we can’t examine it in detail yet, but that hasn’t stopped the MSM from ramping up science by press release stories already. The small figure are from the Nature page on the paper.
Abstract:
Recent temperature extremes at high northern latitudes unprecedented in the past 600 years
Martin P. Tingley & Peter Huybers
- Nature 496, 201–205 (11 April 2013) doi:10.1038/nature11969Received 01 September 2012 Accepted 29 January 2013 Published online 10 April 2013
Recently observed extreme temperatures at high northern latitudes1, 2, 3, 4, 5, 6, 7 are rare by definition, making the longer time span afforded by climate proxies important for assessing how the frequency of such extremes may be changing. Previous reconstructions of past temperature variability have demonstrated that recent warmth is anomalous relative to preceding centuries2, 8, 9 or millennia10, but extreme events can be more thoroughly evaluated using a spatially resolved approach that provides an ensemble of possible temperature histories11, 12. Here, using a hierarchical Bayesian analysis13, 14 of instrumental, tree-ring, ice-core and lake-sediment records, we show that the magnitude and frequency of recent warm temperature extremes at high northern latitudes are unprecedented in the past 600 years. The summers of 2005, 2007, 2010 and 2011 were warmer than those of all prior years back to 1400 (probability P > 0.95), in terms of the spatial average. The summer of 2010 was the warmest in the previous 600 years in western Russia (P > 0.99) and probably the warmest in western Greenland and the Canadian Arctic as well (P > 0.90). These and other recent extremes greatly exceed those expected from a stationary climate, but can be understood as resulting from constant space–time variability about an increased mean temperature.
Figure 1: Time series of temperature anomalies and centennial slopes.
a, Average land temperature between 45° N and 85° N (black), 90% pointwise (blue shading) and pathwise (grey) credible intervals20 (see Methods); the unweighted average of all available instrumental observations (magenta)
Figure 2: Warm and cold extremes.
a, The proportion of draws (see Methods) for which 2003 and 2010 were warmest, and for which the warmest year fell in the 1990s and 2000s. White shading indicates zero. b, The fraction of all locations for which years were warmest
Figure 3: Histograms of temperature anomalies and instrumental maxima for the period 1992–2011.
a, Histogram of temperature anomalies across locations, ensemble members and years for the interval 1992–2011 (blue); the simulated distribution of temperature anomalies, using median parameter values fitted over 1400–2011 (black)
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There are a number of SI files though:
PDF files
-
- Supplementary Information (8.3 MB)
- This file contains Supplementary Figures 1-53 with legends, Supplementary Tables 1-6, Supplementary Discussion and additional references.
Zip files
-
- Supplementary Data 1 (630 KB)
- This file contains the instrumental data sets used in the analysis, in both original form and standardized as described in the Methods, in Matlab and .txt formats. Also included is a short ReadMe document that describes the data files.
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- Supplementary Data 2 (716 KB)
- This file contains the tree ring density data sets used in the analysis, in both original form and standardized as described in the Methods, in Matlab and .txt formats. Also included is a short ReadMe document that describes the data files.
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- Supplementary Data 3 (218 KB)
- This file contains the varve data sets used in the analysis, in both original form and standardized as described in the Methods, in Matlab and .txt formats. Also included is a short ReadMe document that describes the data files.
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- Supplementary Data 4 (262 KB)
- This file contains the ice core data sets used in the analysis, in both original form and standardized as described in the Methods, in Matlab and .txt formats. Also included is a short ReadMe document that describes the data files.We are unable to host the Supplementary Code and Model output files and these can be found at the following link:- ftp://ftp.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/tingley2013/tingley2013.zipThese files contain a number of model outputs, available, where possible, in both Matlab and .txt formats. Also included are a number of Matlab scripts that manipulate the model output to reproduce the main features of the analysis, and a short ReadMe document that describes the data and files.
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Proxy-til-they-drop, is all they’ve got left in the tank. It’s what worked before in the glory days. And man, can they ever turn this stuff out!! Too bad the AR5 draft was leaked so soon – it put these guys in overdrive – they were given a deadline and marching orders. Surely it’s “unprecedented” that one proxy after another, all of which say the same thing, is so readily published in such a short time. A proxy derby. Can Steve McIntyre keep up?
dabbio:
You raise the interesting issue of splicing when you ask at April 11, 2013 at 3:33 am
Few proxies indicate the temperature of individual years: they indicate the average of temperatures over several years.
For example, consider growth of tree rings in a tree as a proxy for temperature. There are many reasons why the growth may vary; e.g. the tree’s bark eaten by deer, the tree’s nutrients increased by death of an animal burrowing near its roots, bears doing what they are said to do in woods near or not near to the tree, etc. It is assumed that over several years (e.g. 100 years) all these factors cancel out to leave the growth indicating temperature. But that means the temperature is an average of the sampled time (e.g. 100 years).
Hence, proxies are said to have low temporal resolution (in the example, the tree only resolves temperature averaged over 100 years).
The temperature measurements have higher temporal resolution: they measure average temperature over single years.
This has several effects and two important effects are
(a) lack of recent proxy data
and
(b) inability to directly compare the proxy data to the temperature measurements.
If the average time indicated by a proxy is 100 years then the most recent indication is for temperature centered on 50 years ago: there is no data for more recently than that.
And the datum from the exampled proxy for temperature 50 years ago is not the same thing as the temperature measured 50 years ago. Global temperature rose ~0.8 deg.C over the twentieth century and the temperature measurements show this. But a proxy averaging over 100-year periods would provide the average rise over that century which was ~0.4 deg.C. Clearly, splicing the proxy indications onto the temperature measurements is very misleading.
The degree that such splicing misleads increases as the temporal resolution of the proxy reduces.
I hope this is a sufficiently clear and adequate answer.
Richard
dabbio says: April 11, 2013 at 3:33 am
“Someone please tell me again: Why is it that we cannot have proxy records right up to the present day? I recall that there is some reason why we cannot rely on them in the present. But if valid proxy records to the present do exist, and if they fail to show an increase, isn’t that the real story?”
Proxy records do not have short term resolution of temperature estimates, only long term….
richardscourtney says: April 11, 2013 at 4:01 am
Sorry Richard, I was a bit slow….
The 2nd graph shows about +/-0.4 deg C accuracy 400 years ago. Impressive ! It’s better than today’s instrumental record.
If there are upticks in last century or so and proxy records have low temporal resolution necause they need time to “settle down”, perhaps we are simply observing the process of the proxies settling down?
Ben D:
re your comment to me at April 11, 2013 at 4:10 am.
Please do NOT apologise.
I am grateful for your answering the question from dabbio, and dabbio may be more grateful for your answer than for mine.
Different people grasp information in different ways so a variety of answers is always good. One answer to a question having appeared is not a reason for a variety of other answers to a question also being posted whether or not they say the same thing.
There is a lesson for us all in this. We each have things to share with each other so we can learn from each other, and I think our individual ways of sharing are all important.
Richard
richardscourtney says: April 11, 2013 at 4:38 am
You are kind Richard, and might I say, it’s a delight to read your comments here on WUWT…
Richard and Ben, your efforts to educate me are highly appreciated.
I sure hope they un- firewall the paper soon, ’cause i need some help understanding the disrupted climate. We awoke to an ice storm in central Oklahoma yesterday and the trees remained encased in crystal until late afternoon. This is a rare event for central Oklahoma. My Dad’s in his 80’s and he’s never seen ice this late either, although the big pond on his ranch is finally starting to get close to filled after the drought we’ve had for several years, which does happen all the time, but is now our fault, due to Global Warming, or so they say.
There is some way to attribute this to Global Climate Disruption, but I can’t remember how it goes, let’s see… warmer air holds more moisture, so that could account for the water to make the ice, but with April showers, maybe not, and then how could it be warmer air, if it’s cold enough to freeze?
My neighbor is all aggravated, because the USDA has revised the local planting dates to match the Global Warmer predictions, but they haven’t yet revised the dates back to account for Climate Disruption, and that is bad for tomatoes.
Maybe some rich and famous “climate personality” will stop by and tell me how it all works,
Looks like I was right….
“Average land temperature between 45° N and 85° N”
—————————————————–
I thought we were looking for global warming not regional.
My guess is they’ll guess for the rest of the global.
cn
FYI, Tingley and Shakun (of Marcott et al.) are both currently junior researchers in the Huybers group at Harvard:
http://www.people.fas.harvard.edu/~phuybers/
Huybers commented on some Mann issues in 2005, although did not seem to work through the criticisms fully.
Huybers could become “part of the solution” in paleo climate issues, unless he continues to be “part of the problem” as the 1960s-speak used to say….
Just an aside, Huybers in 2005 in response to McIntyre and McKitrick:
http://www.people.fas.harvard.edu/~phuybers/Doc/hockey_grl2005.pdf
http://www.people.fas.harvard.edu/~phuybers/Hockey/
Another proxy study where the ‘r’ is silent.
To those are making accusations of ‘trickery’ or ‘manipulation’, you should know that Huybers is a West Point grad and former tank platoon leader during Bosnia. He is a man of integrity (see his inclusion of data and code) and deserves a little more respect.