The House Testimony on global warming yesterday had a number of excellent presentations, and you can watch the entire video here.
I’ve have professor Richard Lindzen’s presentation saved here in PDF form, and some key excerpts below. Part of his presentation looks like WUWT Sea Ice news. It is well worth the read.
The evidence is that the increase in CO2 will lead to very little warming, and that the connection of this minimal warming (or even significant warming) to the purported catastrophes is also minimal. The arguments on which the catastrophic claims are made are extremely weak –and commonly acknowledged as such.
Given that this has become a quasi-religious issue, it is hard to tell. However, my personal hope is that we will return to normative science, and try to understand how the climate actually behaves. Our present approach of dealing with climate as completely specified by a single number, globally averaged surface temperature anomaly, that is forced by another single number, atmospheric CO2levels, for example, clearly limits real understanding; so does the replacement of theory by model simulation. In point of fact, there has been progress along these lines and none of it demonstrates a prominent role for CO2. It has been possible to account for the cycle of ice ages simply with orbital variations (as was thought to be the case before global warming mania); tests of sensitivity independent of the assumption that warming is due to CO2(a circular assumption) show sensitivities lower than models show; the resolution of the early faint sun paradox which could not be resolved by greenhouse gases, is readily resolved by clouds acting as negative feedbacks.
We see that all the models are characterized by positive feedback factors (associated with amplifying the effect of changes in CO2), while the satellite data implies that the feedback should be negative. Similar results are being obtained by Roy Spencer.
This is not simply a technical matter. Without positive feedbacks, doubling CO2only produces 1C warming. Only with positive feedbacks from water vapor and clouds does one get the large warmings that are associated with alarm. What the satellite data seems to show is that these positive feedbacks are model artifacts.
This becomes clearer when we relate feedbacks to climate sensitivity (ie the warming associated with a doubling of CO2).
Discussion of other progress in science can also be discussed if there is any interest. Our recent work on the early faint sun may prove particularly important. 2.5 billion years ago, when the sun was 20% less bright (compared to the 2% change in the radiative budget associated with doubling CO2), evidence suggests that the oceans were unfrozen and the temperature was not very different from today’s. No greenhouse gas solution has worked, but a negative cloud feedback does.
You now have some idea of why I think that there won’t be much warming due to CO2, and without significant global warming, it is impossible to tie catastrophes to such warming. Even with significant warming it would have been extremely difficult to make this connection.
Perhaps we should stop accepting the term, ‘skeptic.’ Skepticism implies doubts about a plausible proposition. Current global warming alarm hardly represents a plausible proposition. Twenty years of repetition and escalation of claims does not make it more plausible. Quite the contrary, the failure to improve the case over 20 years makes the case even less plausible as does the evidence from climategate and other instances of overt cheating.
In the meantime, while I avoid making forecasts for tenths of a degree change in globally averaged temperature anomaly, I am quite willing to state that unprecedented climate catastrophes are not on the horizon though in several thousand years we may return to an ice age.
Entire presentation is available here: Lindzen_Testimony_11-17-2010 (PDF 1.4 MB)