If you can sacrifice 23 minutes, here is a fun interview with Freeman Dyson (who is 91 now)
In 1981-2006, a quarter of a century, the Earth was mostly getting greener (green color on the map).
Dyson argues that CO2 has many direct and staggering consequences for the life on Earth that are more important than the indirect and questionable influences via the climate. For example, the 40% rise in CO2 since the Industrial Revolution meant about a 20% increase in the agricultural yields per unit area (in average: results vary). I like to use the same square-root formula.
And make no mistake about it, this is a big deal. If you use a naive estimate, you could expect that there would be 20% less food, and perhaps 20% of the world population (over a billion of people) could die of hunger if CO2 quickly returned to the preindustrial levels! Fortunately, the carbon dioxide won't drop quickly, and even if it did, the value 20% could be significantly lowered by better trade, redistribution, and transition to more efficient (although sometimes less tasteful) crops etc.
Dyson also says that the influence of CO2 on the climate is questionable and apparently unimportant. So the worries about the CO2's impact on the climate seem unjustified to him. But he doesn't understand the motivation behind this "religion" so he won't say that the people believing in this stuff are evil. Well, many of them surely are, I would personally say, but yes, in principle, many more may be honest.
Freeman Dyson knows the Japanese chap who was the first man who created a climate model with CO2. It had some positive climate sensitivity – still a lower one than what is popular today, despite the years of decreasing estimates. But Dyson thinks that we can't believe those predictions even if the climate models may be a good tool to explain the past observations. We may simply happen to incorporate a sufficient number of mechanisms and terms that may yield a good model of the past data; but this may still be "on the edge" and the future evolution may very well reveal and depend upon some aspects that were neglected in the past but will be important in the future.
Listeners also learn that Dyson spoke to Nir Shaviv who is just visiting Princeton. (Dyson clearly likes Shaviv a lot.) I knew that Nir was visiting Princeton because he (Nir) sent me an e-mail, also mentioning that he had a pretty fun conversation with Nima Arkani-Hamed etc. I hope that none of these insights is secret! ;-)
Despite its very formal atmosphere (and maybe partly because of it), Princeton is surely a place for creative, intelligent, non-ideological, bullying-free scientific conversations about important topics. After all, the number of prominent climate skeptics at Princeton is also rather high. Let me mention that climate skeptic Will Happer is a physics professor at Princeton, too. From this viewpoint, I would say that relatively to Princeton, Harvard is much more communist-party-like dictatorship with tons of ideology-driven pseudointellectuals and bullies such as Naomi Oreskes.
There is also a segment in the interview that is dedicated to the sunspots. Dyson says that the solar temperature is constant – well, the output varies by about 0.1% during the solar cycle, but it would give just a tenth or few tenths of a degree on Earth via the Stefan-Boltzmann law. And the total output doesn't seem to change much in the longer run (e.g. from 1600 to 2000 AD), either. But the sunspots influence the activity which may impact the terrestrial climate indirectly, and by higher percentages.
He mentions diverse and strengthening evidence in favor of cosmoclimatology while he says that the mechanisms – probably involving clouds and cosmic rays but we are not sure – remain less clear (Svensmark might dislike this comment). The interviewer Stuart McNish says that he did some research after watching An Inconvenient Truth and he was surprised that water vapor made... 90 percent of the greenhouse effect. How can you neglect it? Well, you can't, Dyson says. Why people became obsessed with CO2? Because it's a gas we emit and add.
Again, CO2 is so beneficial that it would be crazy to try to reduce it, Dyson tells us. Amen to that.
The interviewer tried to read the IPCC report and it seemed technically hard to me. But he was attracted by the comments about the temperature adjustments. Why are they being done, the host asks? Dyson, like your humble correspondent, answers that the adjustments are desirable because the temperature is a difficult thing and is affected by lots of local effects and details linked to the apparatuses that we want to eliminate when we're interested in some more objective or global information about the climate.
As an analogy, Dyson mentions that Keeling decided to measure CO2 in the Hawaii because it's far from the bulk of the human activity, so this contaminating influence drops away and the reliability of the measurement improves. To measure the global mean temperature, which is rather poorly defined, anyway, we have to measure at lots of places (Hawaii isn't enough for the global temperature) and deal with lots of confusing local distortions.
Dyson praises the weather forecasts and the role of computer models in the improvements – up to a week, the weather forecasts are doing well. The 10-year timescale hasn't been mastered, however (or 2 weeks from now, the interviewer quips). Benjamin Franklin was a pretty good weather forecaster because he was 1) more skillful than most others and 2) out in the open air which helps.
Almost none of us (perhaps with the exception of Dyson) will be around in 100 years from now so we can't know what will happen, the interviewer says. Dyson corrects him that we can be pretty sure of lots of things about the year 2115. He didn't mean the motion of the celestial bodies, however. Among the near certainties, Dyson said that we will keep on burning fossil fuels and the CO2 will keep on increasing. The world will be greener.
What will Dyson say to the people who want to share Dyson's optimism but who are cowards without balls and don't want to oppose the fashionable climate doomsday cult?
Dyson's answer is simple: Become Chinese or Indian. Those Asian nations aren't pessimistic at all – partly because they have seen lots of improvements recently. So the doom and gloom is largely confined to the academic environments, and pretty much only in the Western societies. The media have joined but the general public has lots more common sense. Dyson recommends "Cool It", a book by Bjorn Lomborg.
When the interviewer mentioned that both Lomborg and Willie Soon were vilified, Dyson says that one must enjoy being in the minority. By the way, do I or did I (when it comes to things like climate change among the scholarly folks)? Well, I would say that I could live with that by growing some special kind of pride. But when evaluated in total, I don't enjoy this status. I suffer when I see that most people are deluded about something. And they are deluded about so many things.
Dyson smiles and points out that fortunately, he doesn't have to be afraid of losing his job. ;-)
Is the climate orthodoxy incontrovertible? A top Canadian AGW activist is quoted as recommending to imprison all the climate skeptics. Dyson says that literally, the existence of man-made climate change is a fact. The other questions – which must be asked and must be asked separately – are how strong the effect is, and whether it's good or bad. When things are summed up, the change is small and good, Dyson concludes.
(That's what science says. In the real world of politics, the situation is different. For example, Barack Obama announced that he will fight against CO2 because he believes that this fight will cure his daughter's asthma whose worst episode was actually caused by the smells of a circus and the daughter has allergies. This individual isn't a rank-and-file shaman somewhere in Kenya; he is the president of the leading nation of the industrialized world. You can't make this thing up.)
Freeman Dyson remains optimistic about the world. It may be partly due to his growing up in the 1930s when the world was so much worse. We never expected to survive, he says. Crisis, Hitler, Second World War, threat of biological weapons, other bombs. Your optimism may depend on where you start.