PDO/AMO and Global Climate Change

[Snow_Miser]

If this paper's findings are correct, it would put doubt on the hypothesis that most of the late-20th Century Warming is very likely anthropogenically induced. Also, it's another piece of evidence against those denying the PDO/AMO's influence.

 

Liu 2013

 

We aim to identify the multi-decadal variability relative to the global warming trend in available observation data. First we apply the Hilbert-Huang Transform (HHT) method to the global mean surface temperature (ST_gm) data to obtain a centennial global warming trend. Then the associated signals to the global warming trend are removed from three sets of climate variables including SST, ocean temperature from surface to 700 m, and the NCEP and ERA40 reanalysis, respectively. All detrended variables are low-pass filtered. Through three independent EOF analyses of the filtered variables, all consistently show two dominant modes with their respective temporal variability resembles the Pacific Decadal Oscillation/Inter-decadal Pacific Oscillation (PDO/IPO) and the Atlantic Multi-decadal Oscillation (AMO). The spatial structure of PDO-like mode is characterized by an ENSO-like structure and hemispheric symmetric features. The eigenvectors of AMO-like mode feature overall warm SST anomalies in the Atlantic and Pacific basin north of 10oS. The atmospheric structure associated with the AMO-like mode also exhibits hemispheric asymmetric features with anomalous warm air in Eurasia, and cold air over southern oceans. In the past 30 years, the evolution of PDO-like and AMO-like oscillations gives rise to strong temperature trends resembling negative-phase PDO mode in Pacific, and positive-phase AMO mode in Atlantic. Globally, the two multi-decadal oscillations contribute an important part of the ST_gm warming. The two oscillations are expected to slow down the global warming trends in the next decade.

[tacoman25]

Global warming trends clearly already slowed over the past decade, so they aren't exactly out on a limb predicting this will continue, especially when the AMO goes negative.

 

But hey, no one was predicting this a decade ago, so nice to see some acknowledgement of reality.

[AvantHiatus]

Vice versa as well, a large portion of the 21st century temperature hiatus can be attributed to changes in natural climate oscillations. The overall influence of AGW is questionable when overlayed with other climate forcers, though Co2 is just strong enough to allow for gradual warming and the effect of greenhouse gases may be multiplied under certain favorable periods in the natural variability.

 

Discussing global warming in terms of just Co2 is a foolish mistake.

[Snow_Miser]

Global warming trends clearly already slowed over the past decade, so they aren't exactly out on a limb predicting this will continue, especially when the AMO goes negative.

 

But hey, no one was predicting this a decade ago, so nice to see some acknowledgement of reality.

 

Yep, the 12 year trend has slowed to the point where it's actually gone negative in recent years.

 

[Snow_Miser]

Vice versa as well, a large portion of the 21st century temperature hiatus can be attributed to changes in natural climate oscillations.

 

The next 10-20 years will be crucial in isolating natural variation from human induced changes.

[AvantHiatus]

Yep, the 12 year trend has slowed to the point where it's actually gone negative in recent years.

 

 

Looks like temperatures will stabilize and increase within the next few years if the PDO trends hold any water. I don't see anything alarming or unexpected on that graph.

 

Elliot Wave Principle

 

[Snow_Miser]

this is a copy of a talk given at a conference. it's not a peer-reviewed journal article and its findings are unvetted. it is highly disingenuous to cite it as "Liu 2013" as if it were a published paper.

and LOL at where is conference talk is being touted on the web:

http://hockeyschtick.blogspot.com/2013/06/paper-finds-50-of-warming-over-past-30.html

The PDO/AMO causing multidecadal fluctuations over the course of the long term trend is legitimate science. It's been well documented by many papers.

[Snow_Miser]

that doesn't change the fact you started a thread and misrepresented the 'evidence' you offered.

Or maybe I was unaware that it wasn't a peer reviewed paper. None of that disproves the author's conclusions, or the the other papers that support a large PDO/AMO influence on global warming trends.

[Isotherm]

Or maybe I was unaware that it wasn't a peer reviewed paper. None of that disproves the author's conclusions, or the the other papers that support a large PDO/AMO influence on global warming trends.

 

 

The term "peer reviewed" is often used synonymously with "objectivity" (and inaccurately so), but the truth is peer reviewed literature can be just as biased (sometimes more) than non peer reviewed papers. In today's day and age of agenda driven policies in all aspects of our lives, the term "peer reviewed" holds little weight to me.

[A-L-E-K]

The term "peer reviewed" is often used synonymously with "objectivity" (and inaccurately so), but the truth is peer reviewed literature can be just as biased (sometimes more) than non peer reviewed papers. In today's day and age of agenda driven policies in all aspects of our lives, the term "peer reviewed" holds little weight to me.

 

 

 

jesus christ, what a joke of a post

[ben4vols]

The peer review process, while good intentioned, is broken and leads to more problems than it solves. 

[Jonger]

what it means, by not being peer-reviewed, means that none of it ipso facto proves the author's conclusions as they have not been through the vetting process.

 

it's really misleading to tout non-peer-reviewed papers as published, vetted science. 

 

You better be ready to embrace the post peer review world, information isn't bottle-necked anymore, we have alternative viewpoints and its spreading to ALL fields.

[Snow_Miser]

what it means, by not being peer-reviewed, means that none of it ipso facto proves the author's conclusions as they have not been through the vetting process.

it's really misleading to tout non-peer-reviewed papers as published, vetted science.

That doesn't mean that any of the conclusions are wrong, especially when it is supported by many published papers on the subject.

Also, I've already explained to you that I wasn't aware that it was not a peer reviewed paper. That's not being misleading, it's an honest mistake.

[Jonger]

personal attacks aren't really suitable for this forum.

 

I removed what I felt was very border line... None the less, its gone.

[Bozart]

I removed what I felt was very border line... None the less, its gone.

Then why are you still here?

 

 

 

So, staff, now we're building the case against peer review in CC? On AmWx? And an illiterate fish monger leads the way! What a joke...

 

Donation? You should be paying money out to your dwindling science-inclined posters!

[ORH_wxman]

This is silly...if the OP had just did a bit of searching, much of it (though not all) is already mentioned in Zhou and Tung 2013 :

http://journals.ametsoc.org/doi/abs/10.1175/JAS-D-12-0208.1

[Jonger]

I removed what I felt was very border line... None the less, its gone.

Then why are you still here?

 

 

 

So, staff, now we're building the case against peer review in CC? On AmWx? And an illiterate fish monger leads the way! What a joke...

 

Donation? You should be paying money out to your dwindling science-inclined posters!

Stalk much?

[ben4vols]

So, staff, now we're building the case against peer review in CC? On AmWx?

 

Peer review is flawed and builds plenty of cases against itself. 

[Bozart]

Peer review is flawed and builds plenty of cases against itself. 

Well, if it's perfection you demand, staff all editorial boards with illiterates! You'll be in heaven!

[LocoAko]

As an aside, if you had legitimate research, why wouldn't you get it peer-reviewed? Even the people arguing against it in this thread (lol) are claiming it is at worst equal to non-peer reviewed sources, and most of the world (and the entire research community) takes things much more seriously when they're peer-reviewed...

[ben4vols]

Well, if it's perfection you demand, staff all editorial boards with illiterates! You'll be in heaven!

 

Perfection is probably unrealistic and unattainable but more transparency can be achieved. 

[Snow_Miser]

no, it doesn't mean any of its conclusions are ipso facto right.

I agree that peer review is a golden standard for science. However, just because something is not peer reviewed doesn't automatically make it wrong.

[Snow_Miser]

This is silly...if the OP had just did a bit of searching, much of it (though not all) is already mentioned in Zhou and Tung 2013 :

http://journals.ametsoc.org/doi/abs/10.1175/JAS-D-12-0208.1

Yep, Zhou and Tung is peer reviewed, and one of the papers I alluded to that support a significant influence from ocean cycles.

[ORH_wxman]

 

Yep, Zhou and Tung is peer reviewed, and one of the papers I alluded to that support a significant influence from ocean cycles.

 

You would have saved yourself a lot of grief if you cited Zhou/Tung 2013 if your intent was to show that global ocean cycles have a large contribution to the recent warming trend. Their conclusion was that the 32 year warming trend since 1980 was roughly 0.07C per decade anthropogenic which is about half of the total observed warming trend since then.

Posting a link to just a talk is going to get shot down quickly without peer review support.

[skierinvermont]

 

 

You would have saved yourself a lot of grief if you cited Zhou/Tung 2013 if your intent was to show that global ocean cycles have a large contribution to the recent warming trend. Their conclusion was that the 32 year warming trend since 1980 was roughly 0.07C per decade anthropogenic which is about half of the total observed warming trend since then.

Posting a link to just a talk is going to get shot down quickly without peer review support.

 

Of course Zhou and Tung is not a very definitive paper itself either. The evidence presented is only a very simple regression analysis and this analysis doesn't even include other possible variables like anthropogenic aerosols. A regression analysis cannot prove causation. It can only show correlation. Given that there are other equally strong correlations that exist, a conclusion of causation is speculative at best. Equally strong regression models can be created that do not include the AMO but find much higher anthropogenic causation.

[ORH_wxman]

Of course Zhou and Tung is not a very definitive paper itself either. The evidence presented is only a very simple regression analysis and this analysis doesn't even include other possible variables like anthropogenic aerosols. A regression analysis cannot prove causation. It can only show correlation. Given that there are other equally strong correlations that exist, a conclusion of causation is speculative at best. Equally strong regression models can be created that do not include the AMO but find much higher anthropogenic causation.

 

Yes, like Foster/Rahmstorf 2011. Both methods have similar issues, but at least they are peer reviewed and offer some analysis behind it.

 

Whether we believe it to be robust or not is up to the reader. But he shouldn't have posted a talk vs a paper which basically was saying a similar conclusion.

[Snow_Miser]

You would have saved yourself a lot of grief if you cited Zhou/Tung 2013 if your intent was to show that global ocean cycles have a large contribution to the recent warming trend. Their conclusion was that the 32 year warming trend since 1980 was roughly 0.07C per decade anthropogenic which is about half of the total observed warming trend since then.

Posting a link to just a talk is going to get shot down quickly without peer review support.

Right. I had already started a thread for the Zhou and Tung paper though. Thus, I thought the results from the talk would also be interesting to discuss. Clearly, many people did not think it was too interesting without being peer reviewed.

[donsutherland1]

Peer review is flawed and builds plenty of cases against itself. 

 

For all its flaws, it is far better than an alternative where there is no peer review. At least some degree of vetting takes place (IMO, the process is robust, even if it is not perfect). The process helps assure that research conclusions are supported by credible evidence, research methodology is sound so that the findings are what they are represented to be, etc.

[Isotherm]

For all its flaws, it is far better than an alternative where there is no peer review. At least some degree of vetting takes place (IMO, the process is robust, even if it is not perfect). The process helps assure that research conclusions are supported by credible evidence, research methodology is sound so that the findings are what they are represented to be, etc.

 

 

It's a process. Whether it's good or not is up for debate, but having a process is better than no process, I agree there. Of course with that being said, non peer reviewed studies can certainly provide factual information. There's going to be a bias in everything, and part of the duty of the reader is to become knowledgeable about those potential biases. We've got to weigh the various biases against each other to come up w/ the most truthful solution/answer.

[ben4vols]

For all its flaws, it is far better than an alternative where there is no peer review. At least some degree of vetting takes place (IMO, the process is robust, even if it is not perfect). The process helps assure that research conclusions are supported by credible evidence, research methodology is sound so that the findings are what they are represented to be, etc.

 

Yeah, I understand the argument for it and it is a valid one.  I just don't know if it actually is better than the alternative.  Is a less transparent Gatekeeper of sorts worse than a more transparent Gatekeeper?