As for Black Swans, I haven’t read the book (I hope to do so) but I’m somewhat familiar with his arguments. So I always try to stress the fallibility of long-term forecasts (including my own), the significance of discontinuities in history (both past and future), the importance of identifying truly fundamental trends instead of ephemeral ones, etc…

I don’t know if I can make you dismiss futurism as fantasy. In some sense it is, the more so as you go down the future far enough (incidentally, one of my goals is to write a fantasy book set 1000-3000 years in a wet, hot world with no more accessible fossil fuels!). Nonetheless, I do think that there is some hope for making more or less reliable predictions down one generation – e.g., Japan’s population will age; renewables won’t displace fossil fuels as the dominant power source; computers will be far more powerful and intelligent; ABM systems will proliferate, etc…

From the reviews I have read of War and Peace and War (this is an excellent one – actually I recommend that entire site to you, it is right up your alley) Turchin places a lot of stock in Ibn Khaldun’s “Asabiya” – in Khaldun’s words, “mutual affection and willingness to fight and die for each other”, in Turchin’s “the capacity of a social group for collective action”, and in most normal folk, “social cohesiveness”. (I have heard ‘social solidarity’ as well, but I like the cohesive rendering better).

Now, I have not read the book, but from what I have read about the book Turchin has developed a model for the creation, and decline of cohesiveness in human societies. While material (or as seems to be the case here, geographic) conditions might have an effect on this sense of solidarity, social cohesion itself is a matter of ideology and culture – in other words, fully within the realm of public morality.

Which is an interesting idea in and of itself. If you can unite a people through a devotion to common creed and brotherly identity, how much easier is it to get them to sacrifice “for the greater good”? Where else lies the source of any civilization’s greatest accomplishments? I am attracted to his work because I feel this makes a great deal of intuitive sense – those groups with the highest amounts of social capital have the highest capacity for working together as a group. A society divided by culture wars is a society bereft of this capital.

**

As an aside, I notice you wrote quite a few words on Mr. Ferguson, but none of Mr. Taleb, the man of honor at Ferguson’s table. I have been wondering for a while now if you would ever take up the challenge Taleb poses. I will admit that Taleb’s black swans have changed the way I look at forecast and futurists quite a bit. As an aspiring futurist, you might do well to read his book and provide a rebuttal, lest others like me dismiss the entire project as fantasy.

http://www.nature.com/ngeo/journal/v2/n8/abs/ngeo578.html

– note that they give an increase of 5-9 C above the late Paleocene baseline.

Also, if I’m reading this right, they’re using a carbon cycle model that postdicts a release of about 3000 gigatons of carbon — roughly equivalent to all current fossil fuel reserves. And that’s going into an atmosphere that was already CO2-rich compared to the present.

Paleoclimatology is a very fast-moving science. It barely existed a generation ago. We weren’t even clearly aware of the PETM until the 1990s, and the first paper on the Azolla Event came out around 2004 IMS.

So, view anything more than five years old with some skepticism. If it’s older than ten years, don’t even bother — go and look for something more recent.

– Minor correction on an earlier post: the Sahara excursion happened at the Oligocene-Miocene boundary, not within the Oligocene. Something weird happened at the end of the Oligocene: the Antarctic icecap (which had formed at the end of the Eocene) shrank back almost to nothing, while global climate simultaneously warmed and dried for a while. Then, a few million years later, it went into reverse, sort of — the climate cooled again, and the icecap came back. Things got wetter too, but not as wet as they had been: the huge deserts of the Oligocene-Miocene boundary were replaced by a mix of deserts, savannah and grasslands similar to modern Earth.

Why? An honest paleoclimatologist will tell you: we have no goddamn idea.

Doug M.

That graph is from Boucot and Gray (2001), “A critique of Phanerozoic climatic modes
involving changes in the CO2 content of the atmosphere”. Boucot and Gray were being deliberately contrarian in that article; they thought that estimates of global temperature changes had become much too wild, with some estimates claiming variation of 30 C across the Cenozoic. So they came up with an estimate based on (some) biogeographic data that purported to show much smaller swings.

They intended this as a provocative counterargument, and it worked; the paper has been widely cited. However, its was a deliberate oversimplification that has since been aggressively attacked by, well, pretty much everyone. Even Boucot has backed off from it (don’t know if Gray has).

But ironically, because it supports the “small changes will cook us!” concept, it’s gained wide circulation among global warming alarmists. I say “ironically” because Boucot and Gray were, if not climate change skeptics, certainly among the more conservative interpreters of the data — they thought that increasing CO2 levels, alone, would cause much less change than expected, because various biogeochemical cycles would tend to buffer the effects. I don’t know if they’re aware of how their graph is being used, but if they are, they’re probably ticked.

Here’s a tip: any graph that purports to give global temperatures before the Pleistocene should be read in the context of an accompanying paper. There is still fierce and continuing controversy on a lot of these issues. To oversimplify a complicated topic, you have biogeographic data (which can be reasonably complete, but has problems), isotope ratios, especially oxygen isotopes (can be very complete, but has big problems) and CO2 sampling (useful but rare). Pleistocene temperatures can be inferred a lot more accurately (1) because we have a large database of atmospheric samples, and (2) it’s so recent that biogeographic stuff is much more compelling — landmasses hadn’t moved much, and organisms were identical or very similar to contemporary ones. Go back to the Paleogene, and that’s no longer the case.

An increase of 5 C could not melt the Antarctic ice caps. (Most of the interior of Antarctica never gets above -20 C.) Nor would it give us any of the craziness we saw during the PETM, like alligators on Ellesmere Island and tropical invertebrates north of Newfoundland.

The PETM /started/ with a 5-6 C temperature increase over the pre-existing late Paleocene — which was already a warm ice-free world, with temperate hardwood forests on the coasts of the Arctic.

BTW, my claim of “20 C” was towards the high end (though not without support!). But the consensus would put the global temperature difference at over 10 C — that’s pretty firmly supported by deep sea data — and I don’t think you could find anyone today claiming the PETM was as little as 5 C warmer than today.

Doug M.

The latest forecasts tend to be on the high side of the IPCC’s estimates (e.g. 5C), i.e. will result in PETM-like temperatures by 2100 (given the short timespan, wide adaptation is very unlikely to succeed). Many of these later models also have “fat tails”, extending up to as much as 11C (e.g. The Tale of the Fat Tail by Melinda Kimble and Letha Tawney for an explanation). If reality happens to fall on the far side of those tails, the resulting temperatures will be off the paleoclimate charts and I do not think it can be excluded that the GW process becomes truly runaway.

Not that I’m saying a runaway effect is the likeliest, or even a likely, outcome – just that it is possible if 1) climate sensitivity is higher than indicated by the models, or 2) the Arctic methane releases occur much faster than expected.

Incidentally, I have The Rise and Decline of Nations in a pile on my desk right now, where it has been since I took it out of a library a few months ago. I stopped reading it after discovering the first few dozen pages consisted of a tiresome, banal discourse about the inescapability of subjectivity. I do hope to finish it sometime though, since it was highly recommended by a few people I know.

10-12 C puts us in the Oligocene, ~25 mya. That could be pretty bad — during the Oligocene, the Sahara stretched from the Atlantic to China — but it’s still not, by itself, a mass extinction event.

It would need an increase of around 20 C to put us at the Paleocene-Eocene Thermal Maximum (PETM). The PETM was pretty freaky; the North Shore of Alaska was warm temperate, and tropical rain forest reached as far north as modern New York. The Arctic Sea was warm enough for swimming. Antarctica was ice free except at high altitudes — in fact, the whole Earth was without ice except for a few small patches on very high mountains.

And yet, life — including what passed for humans back then (lemurs, basically) — came through just fine.

Note that at the time of the PETM, 55 mya, the Sun was just about as bright as it is today. (The long-term warming trend is about 1% per 150 my. So, 55 mya gives a difference was of about 0.3%.) So, the PETM probably stands as a proof-of-concept: we could melt the Antarctic ice caps and turn San Francisco into Kinshasa, and that still wouldn’t be enough to trigger Venus-style runaway greenhouse.

Doug M.

One thing I observed is that it is always the easiest targets that are attacked – e.g. intellectuals, “decadence”, etc. Even the post-1970’s America is a good example – it is rap, teen promiscuity, abortion, etc, that is attacked in its “cultural wars”, while the near-permanent primary deficits, deindustrialization, soaring inequality, etc, are ignored. The root problems are not solved – assuming they are even at all solvable – and the internal rot goes on.

I would not be so quick to claim that the two are unrelated. While I do not agree with all that is said in this analysis, I do sympathize with the spirit behind it. Material determinism has never been my thing; as far as my mortal mind can deduce, the common attitudes and beliefs of a society reflect its ability to maintain cohesion and engage themselves in an effort for the long haul. I am told that Peter Turchin (of cliodynamics fame) makes a similar case in his book, War and Peace and War. (Though like Tainter’s work, I have not yet read it. I plan knock both of these off – in conjunction with Mancur Olson’s The Rise and Decline of Nations sometime this summer.