Is the tropical troposphere data a dagger in the heart of the anthropogenic global warming theory?

Question

A recent paper by Douglass, Singer, Christy et al claimed that because the tropical troposphere is not warming as much as the AGW theory predicts, the warming is most likely due to natural causes.

Ignoring the flaws in the "natural causes" theories, let's examine their claims regarding this flaw in the theory. There are many issues with the measurement of the tropospheric temperature. Satellites and ballons all have biases which need to be corrected in order to accurately measure the tropospheric temperature.

RealClimate analyzes the paper and troposphere measurement and concludes:

"This...is a demonstration that there is no clear model-data discrepancy in tropical tropospheric trends once you take the systematic uncertainties in data and models seriously. Funnily enough, this is exactly the conclusion reached by a much better paper by P. Thorne and colleagues. Douglass et al's claim to the contrary is simply unsupportable."

How do you feel about Douglass et al's claims?

RealClimate discussion:

http://www.realclimate.org/index.php/archives/2007/12/tropical-troposphere-trends/

Charles - the conflict is that the Singer paper claims the tropical tropospheric temperature data disproves the AGW theory.

The RealClimate entry analyzes both their paper and the temperature data and disagrees.

Answer 1

If what Gavin Schmidt says is true (that Douglass et al. used an earlier uncorrected version of the radiosonde data, and knew there was a better one, and knew the better one didn't support their conclusions), that is scientific malfeasance. Especially if there is no mention of why they used the earlier dataset.

It is shady approaches to data analysis such as this which are why the climate skeptics, even the more scientifically credible among them, are steadily losing traction, scientifically and politically. You can only lie for so long, especially when everything about climate is so intensely scrutinized by so many people, before people figure out you are lying.

Edit:

Bob: You might want to point out to Raven that the negative feedbacks didn't work so well on Venus. Just my rationale for not being entirely sanguine that things will work out for the best in the best of all possible worlds. Speaking Candidely, of course.

Answer 2

More work needs to be done, however, I think there is a very high probability that this theory will pan out in one form or another.
My rational is: all stable systems in nature have negative feedback mechanisms. Systems with only positive feedback mechanisms usually collapse because of physical constraints. The earth's climate is a stable system therefore there must be some negative mechanism that will kick in when the temperature rises. We don't know what it is but we can be pretty sure it exists.
The CO2 hypothesis presumes that no negative mechanisms exist which is why I think it mostly likely wrong.

Answer 3

As I understand it the link that you have supplied is so an article that is casting strong doubts on the Douglas, Singer, Christy et al paper. Where is the conflict with the AGW theory?
Sorry to be so thick.

Answer 4

RAVEN - excellent thoughtful answer. But....

The potential positive feedbacks for global warming are numerous and obviously true. One example; snow melts, exposes dark ground, warming speeds up.

There are few even conceptual negative feedbacks. Clouds can go either way, depending on the exact type and altitude.

The Arctic data certainly implies that positive feedbacks are more important at this point.

Here's what's most impressive to me. James Lovelock is a respected scientist who has spent his life studying feedbacks on Earth. He coined the term Gaia to highlight his belief in the self regulating power of Earth.

The data on global warming has convinced him this time is different. Hs latest book "The Revenge of Gaia" is a passionate plea for massive construction of nuclear power plants to fight global warming. It's quite a change for him.

A negative feedback may kick in some time. Do you want to risk your economic well being on the possibility?

Answer 5

It could be, but I would like to think of it as just another nail in the coffin, because there is a very small probability that it could still be true.

http://www.worldclimatereport.com/index.php/2007/12/14/tropical-trends-stir-warming-debate/

Answer 6

I think it is probably another demonstration that current climate models are not reliable predictors of the actual climate and that human inputs into those models is often at near ambient or marginal levels.

Answer 7

I haven't a clue, I really don't.