Oh Mann! Paper demonstrates that tree-ring proxy temperature data is 'seriously compromised'

Michael Mann won’t be happy about this. A new paper now in open review in the journal Climate of the Past suggests that “modern sample bias “has “seriously compromised” tree-ring…

The East Anglia Rococo

Steve McIntyre has a new analysis up, one that has a strong headline. Though as he says, “not in so many words”, but more about techniques and exclusions. He writes:…

Dendros stick it to the Mann

UPDATE3: professor Rob Wilson leaves some scathing comments about the Mann paper. See below. UPDATE2: There’s been some additional discussion on the dendro listserver, and it seems quite clear now…

Mann's hockey stick disappears – and CRU's Briffa helps make the MWP live again by pointing out bias in the data

Shock, awe. Untruncated and unspliced data used in a new paper from Briffa and Melvin at UEA restores the Medieval Warm Period while at the same time disappears Mann’s hockey…

New isotope based temperature reconstruction using McIntyre's 'Starbucks hypothesis' tree core samples

A new paper in GRL published Sep 6th Secular temperature trends for the southern Rocky Mountains over the last five centuries makes use of some tree core sample data gathered…

This is what global cooling really looks like – new tree ring study shows 2000 years of cooling – previous studies underestimated temperatures of Roman and Medieval Warm Periods

Since Princeton’s Dr. Michael Oppenheimer conflated weather with climate last week, proclaiming a short lived heat wave as “This is what global warming really looks like” in a media interview, it…

Linking the ENSO and PDO induced rainfall of the Pacific Northwest to proxy data in tree rings and lake sediments

From Penn State , another Mann paper with proxy sets, and a divergence problem. At least they are talking about the MWP, or as they call it, the Medieval Climate…

The Neo Paleo Twitter war of Mann -vs- D'Arrigo

It seems that Columbia’s Rosanne D’Arrigo thinks Mann’s tree ring study isn’t representative proxies for volcanic eruptions, nor good for dendrochronology, though Mike Mann seems to think so. This Twitter…

Revkin on the Gergis et al 'on hold' affair

I promised Andrew Revkin yesterday that I’d give his post on Gergis et all some attention, because he’s done a good job of summarizing it all, plus getting some other…

Yamal that hurts! CRU gets touchy, responds to McIntyre and Montford without naming them

From the “he who must not be named” department, comes this sure to be future McI-fodder. UEA/CRU responds in a press release, authored by Tim Osborn, an excerpt: =========================================================== Tim…

McIntyre rebuts Schmidt’s Rant on Yamal

By Steve McIntyre Two days ago, NASA blogger Gavin Schmidt posted an extended rant against me at Real Climate, a rant directed in part at my recent poston Yamal. I’ve…

Another reason trees don't make good treemometers – new tree ring data bias discovered

[Note: My first post in which I had written commentary mysteriously lost all of its content, posting nothing but white space. This is some sort of internal wordpress error, but…

Mann: Trees aren't behaving like I want them to – volcanoes to blame

From Penn State Tree rings may underestimate climate response to volcanic eruptions Some climate cooling caused by past volcanic eruptions may not be evident in tree-ring reconstructions of temperature change…

The behind the scenes bumbling of the hockey stick

Mann oh Mann. Tom Nelson continues to wade through the 5000+ Climategate 2 emails. I’ve selected a few he’s highlighted in the vein of behind the scenes discussion of Dr.…

Paging Mike Mann – your dendrochronologist will see you now

Tom Nelson has another Climategate 2 email well worth reading Dendrochronologists get spanked by guy with expertise in tree physiology and wood anatomy ClimateGate Email 1738 “However, there are bounds…

Mann hockey stick co-author Bradley: "it may be that Mann et al simply don't have the long-term trend right"

Tom Nelson spots a gem in the Climategate 2 emails: Hockey stick co-author Ray Bradley: “it may be that Mann et al simply don’t have the long-term trend right”; “I…

In China, there are no hockey sticks

Reposted from Jo Nova’s site Chinese 2485 year tree ring study shows shows sun or ocean controls climate, temps will cool til 2068 A blockbuster Chinese study of Tibetan Tree…

Internal dissent: "Personally, I think that the tree ring records should be able to reproduce the instrumental record"

Severinghaus and “Hide the Decline” By Steve McIntyre One of the very first contributions to realclimate was an FAQ from Jeff Severighaus on Dec 3, 2004. A year earlier, Severinghaus attempted…

John L. Daly's message to Mike Mann and The Team

Ric Werme writes in comments: When I realized the Climategate 2009 Emails went back many years, one of the first things that occurred to me was there might be Emails…

Roman Period "megadrought" found in the USA southwest

From the University of Arizona, one wonders how such a thing could happen when CO2 was at “safe” levels. They are using bristlecone pines again, which may very well be…

Sheep study confirms a premise of McIntyre & McKittrick 05

Yesterday, I published a press release titled Tree ring widths more affected by sheep than temperature in which researchers in Norway published a peer reviewed study stating: “We found tree ring widths…

Tree ring widths more affected by sheep than temperature

From Wiley-Blackwell, via Eurekalert, something just plain surprising. Nibbling by herbivores can have a greater impact on the width of tree rings than climate, new research has found. The study,…

UEA's response to EIR/FOIA requests – It depends who you are

Guest post by Richard Brearley This post is written to publicise an interesting anomaly in UEA’s (University of East Anglia) treatment of requests sent to it under the Environmental Information…

Trees show no rainfall pattern in last century

I’ve always said that trees are a better proxy for rainfall than temperature. Just looking at how trees cluster around water sources can tell you this. From the Hockeyschtick: New…