Comments on: AR4: "ad hoc tuning of radiative parameters"

By: Mark Chandler

Mark Chandler — Sat, 19 Jan 2008 01:35:12 +0000

Re: #8 I don’t see any GCM in the Covey et al. (2003) paper that is Columbia U. – what are you referring to when you are comparing to GISS?

By: steve

steve — Wed, 09 Jan 2008 18:54:50 +0000

Does anyone know why the “Clear Sky Anomaly” can be so easily dismissed by the modeling community? They blame the 20% difference between satellite data and radiative transport codes on aerosols. To me this seems to be a huge problem for people that are constantly saying that the “physics” underlying the models is correct.

Lindzen never brings it up, and it is plausible, but 20%!

By: Andrew

Andrew — Tue, 08 Jan 2008 13:37:05 +0000

AJ Abrams, indeed sudden a drop off is unlikely. Indeed, its nearly statistically impossible that the prediction that 2008 will be at least the 10th warmest ever over at the Hadley Centre will be wrong. It’s actually not going to happen short a volcanic corruption or the Sun dissapearing. Or some kind of super La Nina. But that only happens after a super El Nino. Next year will be warm, but what about the next decade?

By: John Norris

John Norris — Tue, 08 Jan 2008 03:52:47 +0000

#21 Oliver Morton

Nice find. Certainly plenty of shared ancestry with that set of GCMs!

By: SteveSadlov

SteveSadlov — Tue, 08 Jan 2008 01:07:22 +0000

RE: #32 – That sort of alludes to a global superstormish output. While Bell and Strieber are masters of junk science, I would not completely discount what I refer to as the “overshoot syndrome” – namely, a perturbation of any type, anthropogenic or otherwise, is eventually bound to cause the system to snap back down into ice mode. Someone on another blog put it as “the climate system is currently biased toward lossiness and cooling.”

By: Sam Urbinto

Sam Urbinto — Mon, 07 Jan 2008 23:22:52 +0000

Check the RSS satellite of troposphere for 2007.

By: AJ Abrams

AJ Abrams — Mon, 07 Jan 2008 21:19:35 +0000

Forgot the question part: So the answer to my question is that they (in this case Gavin), have no real response but are stalling for time?

By: AJ Abrams

AJ Abrams — Mon, 07 Jan 2008 21:16:13 +0000

What an interesting read Bender. A few things to note and a question.

1. Gavin comes across as obtuse in his response.
2. His answer was circular logic and thus completely nonsensical.

Let me see if I can articulate why:

1. He states that you cannot cheery pick a specific year to start a trend analysis, but that is illogical. You have to start somewhere, and in giving his criteria you’d actually start 5 years ago, not ten. Regardless of what your starting point for the trend, 1998, 1948 your slope is significantly altered if the last ten years have remained static to what it would have been had temperatures actually gone up for the last ten years. Period.

2. You can’t arbitrarily call any data insignificant without defining the parameters like he did in his response, then use a single year (2005) to prove that there was an upward trend in the same paragraph. It’s using circular logic and not just evasive, but a blatant end around.

3. You can’t comment that any one year’s negative temperature trend can be explained away by looking for a significant negative forcing but at the same time not doing it for positive trends which is what he’s doing in the response.

In short he gives an answer that is no answer and suggests that no matter what date you use or no matter what the trend is over a given time frame that he reserves the right to change the parameters. The only way it seems to circumvent his illogical argument would be for temperature data to drop to pre -satellite era temperatures which while possible isn’t likely.

By: Francois Ouellette

Francois Ouellette — Mon, 07 Jan 2008 21:16:00 +0000

This rather oldish paper (1999) has a good discussion of flux adjustments, and how modelers dealts with it.

By: Michael Jankowski

Michael Jankowski — Mon, 07 Jan 2008 20:31:01 +0000

Olivier has mentionned the problem of snow accumulation reaching several km must be resolved

If a model based on consensus climate science suggests kilometer-thick snow is going to happen as a result of global warming, who are we to argue?

This is in contrast to the typical tuned GCM, which predicts less snow and hurts places dependent on (1) snowmelt for drinking water and (2) snow for their resort economies.

I am sure that once they got the memo, their “untuned” GCM matches the consensus a little better.