Thursday, October 22, 2009

There's Still a Blade

I have an article in the November issue of Scientific American, "Still Hotter Than Ever," that I think is important. It's about a new mathematical method by Martin Tingley and Peter Huybers that reconstructs past temperatures from proxy data, using a Bayesian statistics approach rather than the traditional principal component analysis. Calculating up until the year 2000, it finds... a hockey stick-like result.
Focusing on 600 years of proxy data between 45 and 85 degrees north latitude, Tingley's initial result...finds that the 1990s were the warmest decade of the period and that 1995 was the warmest year.... He also found that the 20th century had the largest rate of warming of any century and that the 1600s had the largest rate of change overall...albeit in the cooling direction due to the Little Ice Age.
It's not a "confirmation" of the hockey stick per se, but a completely different method that points to a very similar result.


26 comments:

rhhardin said...

If it's sensitive to method, it's garbage.

David Appell said...

That's the point of my article -- it _isn't_ sensitive to method.

Bishop Hill said...

An entirely different method, but what about the data?

David Appell said...

What is wrong with the data?

Bishop Hill said...

Is it different?

Bishop Hill said...

Jean S at Climate Audit wonders if it's this one, using Mann's PC1, Tornetrask, Yamal and so on?

Dano said...

The Tingley and Huybers has nothing to do with blades and robustness of recent warming findings.

And the entire planet awaits the contrascience community to provide their own data - perhaps one day the pseudoskeptic community can go out in the field and help provide ideologically correct data to overturn physics, the warmist alarmist econazis and the scientific literature.

Next time I'm at the bookstore, David, I'll pick up the mag.

Best,

D

David Appell said...

Let's be clear: this Tingley/Huybers paper is a proof-of-principle of an entirely new method of reconstructing past climate. It is not intended to be a "confirmation" of the MBH hockey stick, which Martin Tingley was very clear to tell me, though the preliminary results obtained so far have many similar features. Nor is it intended to solve every problem in the field of paleoclimatology, let alone purported problems in the data. (From my reporting, I think scientists believe that that data is pretty good, though data in any scientific field can _always_ be improved, and _is_ always being improved). In any case, this new result ought to, I think, damp criticism that the PCA approach was somehow unsound or flawed, as some have implied.

By the way, I asked Wegman for his thoughts on this new method, but he did not respond.

Jean S said...

I had a quick look on the paper(s) available Tingley's web site. Yes, indeed, the methodology seems pretty advanced (compared to simplistic methodology generally used in multiproxy studies) although there is nothing really "new" about it -- for example hierarcial Bayesian models have long been used in other fields. But that's not the point! If the data used is indeed the one (Osborne&Briffa (2006) set) used in the above paper linked by BH, the reconstruction tells nothing about Earth's temperature history no matter how advanced methods used: garbage in - garbage out.

Jean S said...

Oh, another thing. Mann's PC analysis was unsound and totally flawed, just go to ask any statistician. I thought even this issue was clear after Wegman and Jolliffe took a stand on it, but apparently there are still people calling themselves "journalists" who have not yet got the word.

BTW, Osborne & Briffa proxy set contains proxies constructed with Mann's flawed "PCA" method.

Dano said...

Let me guess: the reason why

Mann's PC analysis was unsound and totally flawed, just go to ask any statistician. I thought even this issue was clear after Wegman and Jolliffe took a stand on it,

isn't found in the scientific literature, and only on the blogs of brave warriors is because of the huge conspiracy of greennazi envirowarmer scientists grubbing for money, right?

chuckle

IOW: pffffft.

HTH.

Best,

D

Anonymous said...

Dano, 3:19 PM

You're mistaken:

http://www.agu.org/pubs/crossref/2005/2004GL021750.shtml

TreyG

Dano said...

Apologies. I tend to shorthand anything the CA (Chorus, Amen) crowd ululates.

I didn't realize I still had to be explicit and state: "The issue is that current warming is greater than the MWP or any other incidents in the recent past."

None of the numerous findings of greater recent warmth are overturned due to anything CA has come up with, and that was my point.

CA has not overturned empirical findings that now is warmer than then.

Apologies for having to write this again. And for shorthanding the obvious. And for presuming the CA crowd meant anything other than 'there is no warmin', and if'n there is, we ain't done it'.

That was my point, poorly executed.

Best,

D

steven said...

Let me guess without looking at the series they used..

I would guess Yamal, something with a stripbark ( which should be avoided) and perhaps an ingrediant from one of Mann's papers.

Same garbage in, different method, same garbage out.

ho hum

Anonymous said...

If the same data was used, then it proves nothing new. When will the "hockey team" get the message and admit they are wrong?

Paul Biggs said...

"The issue is that current warming is greater than the MWP or any other incidents in the recent past."

Problems for that statement: peer reviewed papers on a warm bias in the global average near surface temperature data. The use of selected or flawed proxy data and methodology in order to produce a hockey stick shaped graph - demonstrated conclusively both in and out of peer review. 'Climate Audit' goes beyond the scope of the cursory nature of peer review, which has often failed to require archiving and sharing of data.

This new paper, which seems to be as yet unpublished, uses 14 series which include Yamal, a strip-bark foxtail series, and Mann's PC1.

Next!

Dano said...

Boy, the Chorus, Amen bots have been deployed far and wide, haven't they?

It's a darn dirty shame that ACES will be voted upon. One would think the Chorus, Amen bots would be deployed to the fossil fuel lobbyists so they have another talking point. Oh, wait: it's the same talking point. Never mind...

Best,

D

Brian Macker said...

David Appell,

This is just more garbage. The hockey stick is pseudoscience.

Xinghua said...

Dano,

You seem to be confused. ACES is the death warrant for climate action in the United States.

That's why even Greenpeace is now opposed. If it passes, the US emissions trajectory will remain virtually unchanged, continued climate inaction will be guaranteed until 2020 approaches.

By the time 2020 does arrive, we will have given out close to a trillion dollars to politically connected businesses in order to reduce US emissions by 2% over BAU. Good luck convincing anyone that this was a good idea.

Dano said...

I'm not confused at all, "Xinghua", but thanks for trying.

Greenpeace has an opinion that the coal industry lobbyists have succeeded in trashing the intent of the bill, not that the concept won't work. This sort of logic presumes amendments won't happen.

Again, thanks for trying.

Best,

D

Terry Koch said...

I've always envied the delusional. It must be so, so comforting to know that you're right!

Metternich said...

CA thinks the data is cherry-picked and the PCA method is flawed.

The new result gets the same, more or less, result from old data using a different method.

If we could all agree on a data set to use, lots of different methods could be tried and shown.

But for those who are deeply skeptical about trees as thermometers, no acceptable data set is likely.

Dano said...

CA thinks the data is cherry-picked and the PCA method is flawed.

So what.

Best,

D

Xinghua said...

Dano,

So you agree that the bill will do virtually nothing to reduce emissions, but you still support it?

itisi69 said...

Dano, using phrases such as Chorus, Amen crowd does not make your point any stronger, on the contrary.

If you want to make a real impact, you might adress the CA argumentation with ac tual scientific counter arguments instead of punching holes in the air...

Dano said...

So you agree that the bill will do virtually nothing to reduce emissions, but you still support it?

I agree that the only way you have an argument is to mischaracterize what was written. We see that nothing has changed in the bot world, which is why we are voting on carbon trading, despite all the industry-originated spam.

Best,

D