I would say that most of the competent physicists at good universities who have spent enough time to study the climate change issue are climate skeptics. A good example is Will Happer, an atomic physicist of Princeton.
Today, I checked the list of Berkeley physics coloquia and picked the following November 2010 talk:
CO2: a friend or a foe (MOV video, 90 minutes)Lots of achievements by Prof Happer are enumerated at the beginning; you may want to listen to it carefully and compare with some of the scientific niemands who promote the climate alarm. As soon as the talk begins, it's fun.
Happer begins with the concentration of CO2 outside the building and inside the room which he actually measures by a gadget. It was about 390 ppm outside and 650 ppm in the lecture hall. Within seconds, the gadget was gradually growing to 654 etc.
He says that he's against real pollution – lots of examples are mentioned – but is CO2 a pollutant as the EPA would love to suggest? Properties of CO2 are mentioned. He asked the folks what was the CO2 concentration in your breath. No one knew, except for a guess, 10,000 ppm. Too bad physicists don't know such things. Of course, if I were there, I would instantly scream 40,000 ppm. ;-)
Two theses he wants to demonstrate are that the climate change will keep on going even if CO2 stays constant; and he wants to discuss the optimum CO2 level – assuming we can choose. Well, 150 ppm is too little: plants die and Kelvin already knew that. Geological epochs with thousands of ppm are reviewed. It's nonsense that we're doing an unprecedented experiment with a high CO2; the CO2 has done much greater experiments of this type and high CO2 is good. Seasonal variations of CO2, especially in the Northern Hemisphere, are shown. Most land is over there.
Now, there's time for the greenhouse effect. Absorption and emission spectra of the atmosphere and the Rayleigh scattering are explained in a very sensible, no-nonsense, physics-oriented manner. Cute classical animated visualizations of excitations of the water molecule, the main greenhouse effect molecule, are presented. Rotational modes have low enough frequencies to influence the Earth's thermal radiation. Three spectral lines of CO2 are mentioned.
Temperatures as a function of the altitude are shown, the lapse rate, and so on. Most of the infrared radiation comes from H2O and CO2. Radiation to outer space is the only way for the Earth to cool itself. We're shown some absorption as measured by the satellites and comparisons with the black body curve. The greenhouse gases don't stop the radiation from escaping; it's just emitted from the top of the troposphere at a colder temperature.
The spectra at 280 ppm and 380 ppm of CO2 show almost no noticable difference. Even another doubling has a tiny effect.
The logarithmic dependence on the concentration is shown; it only breaks down for very low concentration because the temperature change doesn't go to minus infinity as the logarithm suggests. To compare, the clouds have huge and obviously visible impact on the spectra. Happer considers clouds to be the main players that influence these flows of radiation.
When he talks about the Vostok ice core data, he reviews the usual things and also discusses the dust. There was much more dust when the Earth was cold. This means that a colder Earth had many more deserts – exactly the opposite than what the climate warriors love to say, contrary to the evidence.
Temperatures in the last millennium – the developments of non-hockey sticks and hockey sticks – are discussed using IPCC graphs and historical knowledge – including details of the organization of the thriving agricultural society in Southern Greenland during the Viking period. The hockey stick, especially the shaft, is one of the most discredited charts of science, Happer states. The satellite-era graphs of the temperature are said to have lots of instabilities: ENSO, volcanoes contribute something.
Yields from the crops went up by dozens of percent while CO2 went from 280 ppm to just 390 ppm. The plants are also able to resist dryness etc. Gadgets are actually sold to burn carbon and to triple or quadruple CO2 in the greenhouses and people have good reasons to buy them. That's how these questions are addressed if the political pressures are avoided and people are allowed to search for profit.
Stomata are discussed, redwoods etc. At a lower CO2, plants need more stomata to import the gas which makes them less resilient.
Sea level rise: 140 meters in the last 20,000 years, mostly between 16,000 and 8,000 years ago. It's fluctuating in both directions these days. In the recent century, it was going up about 2-3 mm per year; the rate seems smaller if not negative in the 5 years before his talk. No way to flood NYC or L.A. or Berkeley in a few hundred years. No acceleration is seen. No trend seen in sea ice in a decade, either. Ice-free regions in the Arctic were shown on 1959 photographs. Ocean acidification isn't a problem: detailed measurements of pH, in a trip to colder places or higher depths, the ocean gets less alkaline (not acidic yet!). The doubling of CO2 changes pH by 0.1 which is much smaller than the natural fluctuations of the ocean. Sea life has adapted; ability to regulate internal pH (pH pumps) were the most ancient gadgets that life had to invent very early during evolution to prosper.
Now, the feedbacks. The bare climate sensitivity is about 1 degree Celsius, the IPCC wants to inflate it to more than 3 degrees, mostly by water-vapor-related feedbacks. IPCC calculations of the sensitivity are highly incompatible with each other – and with observations. And they aren't getting better. Only one oldest model could be OK; models seem to be getting worse (less compatible with observations) with time.
Some cost-and-benefits analysis (William Nordhaus) is reviewed. Doing nothing at least for 50 years is the most sensible option, or at least nearly statistically indistinguishable from the optimum policy.
Happer is wrapping up. Why do people get emotional? It's a secular religion; resistance against any change (Happer is conservative but not conservative enough to resist any change which may be good); inadequate time to study science; governments' desire to increase the revenue (he knows quite something about these matters from his activities in D.C.: Enron could have established cap-and-trade in the U.S.); and finally: we're shown pigs with a quote by Pushkin in Russian (from Dubrovsky, 1832). All you need are feeding troughs and pigs will always come. Lots of money.
The CO2 concentration in the lecture hall went from 650 to 730 ppm during the talk so far (about one hour), almost the same absolute increase as the outdoor increase from the beginning of the industrial revolution (about 250 years).
Questions and answers.
In the first answer, he says that much of the data is still very shaky but the measurements of the oceans' parameters (temperature, pH etc.) look promising. The second guy says that CO2 is just a proxy for other bad things. Happer agrees that coal mining does bad things in general but it shouldn't be extrapolated to the CO2 itself. Methane burning is OK for Happer and there shouldn't be policies that ban it.
Richard Muller is questioning the figure about 1 degree Celsius for the no-feedback doubling CO2 climate sensitivity. He wants to know where it comes from; Muller obviously didn't know much about the greenhouse effect in 2010. Happer's answer seems confusing to me, too. The "experimental" measurement of this figure is linked to Spencer-Lindzen-like analyses of the energy flows. Yes, 1 degree is closer but it's not the no-feedback value. The no-feedback value is theoretical! Muller asks how Happer dares to reach a conclusion that doesn't agree with the IPCC but once Happer says that the IPCC isn't a scientific organization, Muller approvingly nods.
What will happen with the cloud cover if temperature changes? Happer thinks that clouds regulate the climate, i.e. negative feedbacks. He explains that high (Cirrus) clouds are warming the system, unlike the low-lying clouds. The composition of the clouds is subtle. Clausius-Clapeyron equation matters etc.
Another older physicist says that the hysteria exists because the government needs a crisis to justify its right to exist. The same man asks what's the probability of tripping into an ice age. Happer thinks that no one understands how the ice ages really start. Books, such as Rich's book (looking at Muller haha), don't make much sense if you look closely. ;-) On the other hand, people underestimate the importance of the irregular Earth's orbit. Happer seems to be a Milankovitch skeptic, a position I don't find sensible at all and I will try to convince Will that the Milankovitch explanation is indisputably right immediately, unless he has already changed his mind. Update: Prof Happer responded that he became more convinced that the cycles are an important contributor in the months after the talk...
A visitor makes everyone laugh by saying that he wants to disagree with a lot of things Happer had to say. He asks why CO2 was changing in the distant past. Bob Burner is sold as the world expert on it; mountain building plus plants and lignite etc., semiplausible. The idea of the man is to link CO2 to temperature via coal deposits by an argument I didn't understand, and neither did Happer. He at least disproved some naive theories how to calculate temperatures of the ancient Earth etc. Lindzen's cloud thermostat-like explanation of the faint Sun paradox is mentioned.
Another question asks about the hockey stick graph – someone else agreed it was bogus – and asked something about the hiding of the decline. Happer also talked about tree rings, moisture, etc. Another man says that a slow CO2 rise is OK but can't the fast CO2 rise be dramatic? Happer talks about some geological episodes that could have been fast for various reasons, lots of water etc. There's no evidence that the biosphere couldn't deal with similar changes. 20,000 years ago, CO2 may have been too low to allow systematic agriculture which could be the right explanation why it didn't exist at that time. For Happer and his instincts, Nature is extremely tough and it's his enemy, especially the weeds in his garden that grow much more quickly than his stuff. ;-) He doesn't understand why the visitor (and others, including the speakers of Czech) use a feminime word for Nature. :-)
Lots of people are raising their hands. A guy says that H2O in the atmosphere is very complex. Happer sees convincing evidence neither for amplification nor for reduction of the greenhouse effect by water vapor and clouds in the literature. Neither do I. Even the basic observational data about the evolution of water vapor in the atmosphere is shaky.
A female attendant is finally asking whether she should conclude that we shouldn't fight against the CO2 rise – yes, Happer says, we should do nothing (except that it may be a proxy for mercury in coal etc. but if we can measure the bad things, we should decouple them). Happer says how coal may worsen lives but it's not CO2. She also asked another question. I didn't understand it well but she was apparently looking for another quantity to panic about assuming that the evil CO2 toy is taken from her. ;-) Happer mentioned some random population killers, famines etc., in the past which are vaguely correlated with a cool weather so if there's an optimum temperature, it's higher than the present one.
It's too bad that all the arrogant yet uninformed folks who want to talk about the climate – all these Gores, Hansens, Manns, and similar jerks – can't be forced to learn the basic physics of these physical systems, at least at the level of Prof Happer's talk.