Kenneth Brower, son of Sierra Club transformer David Brower, and onetime friend of Freeman Dyson, has been writing about Dyson and climate change. As is usual with books by writers who are not scientists, the scientific issues are not addressed. Those are settled. Instead the purpose of the article is to find out why Dyson, so brilliant, has gone so wrong.
Having myself grown up in Berkeley, where Nobel laureates are a dime a dozen, I certainly know the syndrome: the mismatched socks, the spectacles repaired with duct tape, the forgotten anniversaries and missed appointments, the valise left absentmindedly on the park bench. Yet hometown experience did not prepare me completely for Dyson. In my interviews with the physicist, he would sometimes depart the conversation mid-sentence, his face vacant for a minute or two while he followed some intricate thought or polished an equation, and then he would return to complete the sentence as if he had never been away. I have observed similar departures in other deep thinkers, but never for nearly so long.
Much of the article is like that. The assumption is that Deniers are off their heads, and the only question here is how someone as bright as Dyson could be so wrong.
Regarding absentmindedness, of course it’s true — less so for Freeman Dyson than some, such as John McCarthy who has famously wandered off from a conversation because he was lost in a new thought — but it’s also irrelevant. There’s a difference between being abstracted and being unable to finish a problem or publish a good essay. Minsky and McCarthy are great examples. There’s no requirement for being focused on what interests the other guy in a conversation or even an interview if there’s a better use for your powers of concentration. What matters is the ability to finish the thought, and to use that concentration to think through things before publishing them. And, of course, to ask questions, which Freeman Dyson and other “Deniers” do frequently, and which are ignored by the Believers.
Freeman, for his part, seems to have settled more deeply into his own secular religion, becoming a prominent evangelist of the faith. He is in such a scientific minority on climate change that his views are easy to dismiss. In the worldview underlying those opinions, howeverÃ¢â‚¬â€in the articles of his secular faithÃ¢â‚¬â€he makes a kind of good vicar for a much more widely accepted set of beliefs, the set that presently drives our civilization. The tenets go something like this: things are not really so bad on this planet. Man is capable of remaking the biosphere in a coherent and satisfactory way. Technology will save us.
Once again, there is no discussion of the questions Dyson has asked.
Many of Dyson’s facts on global warming are wrong, as the scientists who have done actual research on the subject point out, but more disconcerting is the selective way he gathers his information and the peculiar conceptual framework into which he inserts it.
It is true that plants grow better with increases in carbon dioxide. (Photosynthesis is the conversion of carbon dioxide and sunlight into organic compounds, so the more CO2 and sunlight, the better, up to a point.) If a plant’s survival depended only on its metabolismÃ¢â‚¬â€if all it had to do was photosynthesizeÃ¢â‚¬â€then increased CO2 in the atmosphere might indeed be a good thing. But plants happen to grow in these little universes we call ecosystems, where they are sustained by complex webs of interdependency with fungi, microbes, animals, and other plants. Much of this mutually dependent life is adapted to narrow temperature and rainfall regimes, and these biomes are collapsing everywhere.
Plants do grow better with increased CO2, but not when deprived of water. Water is a vanishing commodity in the American West, where I live, and where, like the Australians and Sudanese and many others, we are enduring a succession of increasingly prolonged and severe droughts. Drought is a paleontological fact in the American West, but the latest desiccations have a new signature, and my region’s climatologists, hydrologists, foresters, and water managers are nearly unanimous in their conviction that what we are seeing now is climate change, the anthropogenic kind, a consequence of too much CO2 and other greenhouse gases. Drought-induced stress increases plants’ susceptibility to disease, and tree diseases are epidemic now in my home landscape and elsewhere. Plants grow better with increased CO2, but not when they are dead snags.
The planet, Dyson assured Rose, is warming mainly in places that are cold; it is not getting hotter so much as the climate is evening out. This is a peculiar analysis. The fact is that the planet is getting hotter, by small but enormously consequential increments. That the warming is most pronounced in cold places is true, but this is no consolation to the creatures that live there. I recently returned from reporting on diminishing sea ice and the decline of penguin populations and krill stocks on the Antarctic Peninsula, the western side of which, over the past half century, has been warming at five times the world’s average rate. I feel obligated to put in a word for the elephant seals, fur seals, crabeater seals, leopard seals, whales, penguins, albatrosses, petrels, and other members of that cold-adapted, krill-dependent fauna. Dyson’s implication that an evening out of global temperatures might somehow be a neutral or beneficial phenomenon is astounding. Temperature differentials at different latitudes and altitudes are a prime driver of planetary weather. Weather patterns, needless to say, are full of consequence not just for penguins and seals, but for all life everywhere.
Looking at some of the details of the above:
- The fact is that the planet is getting hotter, by small but enormously consequential increments.
This is proof by repeated assertion. Few deny that there has been warming from 1885 to present; there is disagreement as to how much (how many tenths of a degree) and a lot of disagreement about the “enormously consequential” given that there was a lot more warming from 1776 to 1885. Indeed the consequences are what the debate is about. Assuming “enormously consequential” assumes the desired conclusion, which is standard “consensus” reasoning among Believers.
- Plants do grow better with increased CO2, but not when deprived of water.
True of course, but irrelevant. Climate scientists do not understand the mechanisms of El Nino, which has far more to do with rainfall than average global temperature. For most of us, warmer temperatures cause more evaporation, which leads to more water vapor in the atmosphere, which would seem to make rain and snow more likely. If this is not true, one would expect to see some undergraduate level discussions of the relationship between temperature and rainfall, and some kind of chart analogous to the world average temperatures from 1885 to present. Perhaps they are out there but I can’t find them. I do see http://www.climate-charts.com/
World-Climate-Maps.html#rain which seems to show, unsurprisingly, that the areas of the world with the largest rainfall seem to be those with the highest temperatures. Of course there is no discussion of how annual rainfall is measured to the nearest millimeter in all those areas of the world, nor is there so far as I know any attempt to combine all these measures into an annual rainfall number that can be displayed along with the world average temperatures. Is world rainfall going up or down? I found this:
Increasing temperatures tend to increase evaporation which can lead to more precipitation. Precipitation generally increased over land north of 30Ã‚Â°N from 1900 through 2005 but has declined over the tropics since the 1970s. Globally there has been no statistically significant overall trend in precipitation over the past century, although trends have varied widely by region and over time. Eastern portions of North and South America, northern Europe, and northern and central Asia have become wetter.
Thus Brower’s statement Ã‚Â Plants grow better with increased CO2, but not when they are dead snags. Ã‚Â is undoubtedly true, and one suspects that Dyson is aware of that as are most sane people. The relevance is doubtful absent strong negative coupling between local temperature and rainfall, and that is not evident at all. I have seen no convincing coupling between AGW and desertification. We do know that there are manmade deserts: the goat has done a great job of spreading the Sahara into areas that were once the breadbasket of the Roman Empire; but that has long been known (I learned it in high school) and not related to CO2 production. (1)
I could continue, but it would be pointless. Brower’s article, attacking Dyson’s sanity, is typical of the desperation of the Climate Believers. They refuse to answer obvious questions, referring questioners to enormous reports that turn out not to contain those answers; and since they assume that anyone who doubts their conclusions must be mad, they wax eloquently about the reasons why such smart people have gone mad.
Meanwhile I come back to ” Globally there has been no statistically significant overall trend in precipitation over the past century” from Wikipedia. It may or may not be true, but I would suppose that if it were not true someone would have disputed it. If it be true, then the obvious question is, why not? Rainfall is far more important to people than a degree or so of temperature rise. Shifting patterns of rainfall have driven migrations for tens of thousands of years. If the average temperature goes up by a degree it may be less comfortable, but if that brings with it more rainfall the overall livability of an area may be improved, not degraded; while if an area cools but becomes a desert, that would be a different result.
At some point there needs to be a national debate on “climate change”. When that takes place, I will myself place far more weight on the reasoned views of Freeman Dyson than on those of David Brower’s son.
(1) Note: It used to be standard — consensus — theory that the goat was a major cause of the spread of the Sahara north into the older fertile Roman provinces in North Africa. The narrative was: goats, unlike cattle, eat everything, down to the roots, and in an area of marginal rainfall they produce much more bare ground; the ground becomes warmer, so when the rain clouds come over they are kept higher and drop less rain on the area. The goats continue their march, the land becomes warmer, less rain falls, the rain that does fall doesn’t soak in because there are no roots and worm tunnels and such to hold it, and the desert grows. It grows slowly but the growth is fairly steady. Ã‚Â¶ When I say standard theory, I mean that it was taught in science classes in high school, and in Introduction to Ecology at the University of Iowa. The theory may have been disputed by climate experts, but if so they were mainly quiet about it, and historians accepted that the introduction of goats into Tunisia was a climate changing factor of some importance. Modern theory makes this more complex — surprise. See http://www.munfw.org/archive/45th/csd1.htm . Still, no one doubts that deforestation is significant and can cause drastic climate changes http://factsanddetails.com/china.php?itemid=389&catid=10&subcatid=66 . There seems to be little recent discussion of the role of the goat in the spread of the Sahara hrough historic times, but I have devoted little time to searching for this. The point is that there is little to no published evidence that AGW is reducing rainfall.
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