2010-09-29 00:30:05A few AMO papers
John Cook


Just highlighting a few papers on the AMO in case anyone (*coughrobertcough*) ever is interested in writing a rebuttal to "It's the AMO".

On the Persistence and Predictability Properties of North Atlantic Climate Variability

A Significant Component of Unforced Multidecadal Variability in the Recent Acceleration of Global Warming

The problem of separating variations due to natural and anthropogenic forcing from those due to unforced internal dynamics during the twentieth century is addressed using state-of-the-art climate simulations and observations. An unforced internal component that varies on multidecadal time scales is identified by a new statistical method that maximizes integral time scale. This component, called the Internal Multidecadal Pattern (IMP), is stochastic and hence does not contribute to trends on long time scales, but can contribute significantly to short-term trends. Observational estimates indicate that the trend in the spatially averaged \well observed" sea surface temperature (SST) due to the forced component has an approximately constant value of 0.1K/decade, while the IMP can contribute about ±0.08K/decade for a 30-year trend. The warming and cooling of the IMP matches that of the Atlantic Multidecadal Oscillation and is of sufficient amplitude to explain the acceleration in warming during 1977–2008 as compared to 1946–1977, in spite of the forced component increasing at the same rate during these two periods. The amplitude and time scale of the IMP are such that its contribution to the trend dominates that of the forced component on time scales less than 16 years, implying that the lack of warming trend during the past ten years is not statistically significant. Furthermore, since the IMP varies naturally on multi-decadal time scales, it is potentially predictable on decadal time scales, providing a scientific rationale for decadal predictions. While the IMP can contribute significantly to trends for periods of 30 years or less, it cannot account for the 0.8°C warming trend that has been observed in the twentieth century spatially averaged SST.


BTW, I'm adding all these papers and many other hot-off-the-press peer-reviewed papers to the database as I get them. So if you want to get a daily email of all the latest climate links, go to:


I still haven't launched this service yet, it's exclusive to SkS authors :-)

2010-09-29 01:14:08comment
Robert Way

You know, there are times when people would like to relax and not take the most controversial subject every time :P

So lets see what my to do list contains:

1) Ice Sheet Losses are overestimated (Thank you wu et al 2010)
2) Mcshane and Wyner (2010) killed the hockey stick
3) It's the AMO

Oh Joy... I just noticed Loehle's new post... this one is gonna have to be dealt with. It is ridiculous.



Sorry John, i'll try to step it up though... sometimes things like we previously discussed get in the way.
2010-09-29 08:22:10Sorry Robert, no pressure! :-)
John Cook

I think the mcshane rebuttal would be on the back burner until those two peer reviewed rebuttals of mcshane get published. And no rush on the AMO either. As you say, stuff gets in the way.
2010-09-29 08:52:44Slight digression, this one goes in "the stupid, it burns" category
John Cook


Saw this blog post that disproves AGW by pointing out there's no correlation between CO2 levels and the various ocean cycle indices. Thought you might get a kick out of it (but be careful, you get more stupid just by reading it):



2010-09-29 09:22:06comment
Robert Way

Well you were certainly right about the last part... haha