Ice doom of DOOM!

[james_davis_nicoll]

The previous ice age lasted some 110,000 years and ended about 11,000 years ago. In other words, some 4,000 generations of humans knew of nothing but harsh winds and eternal snows. The apparently "normal'' periods between ice ages, like the present one, have averaged between 8,000 and 12,000 years. In short, the next ice age is overdue. The key question is when it will come. Can space be colonised by a sufficiently large population so that, when the next ice age strikes, it will not threaten the survival of the race?

Comments

[keithmm.livejournal.com]

I had a geology prof (actually a paleontologist specializing in trace fossils) who was a living example of that: he still had some doubts about this new-fangled plate tectonics thing. This was in the 1990s.

He also had issues with impact geology. His office was, mind you, right down the hall from one of the world's leading experts on the subject and he was in the department hosting the Earth Impact Database.

[mmcirvin.livejournal.com]

It's actually kind of amazing how late plate tectonics became the consensus position in geology, given how foundational it seems now.

[pauldormer.livejournal.com]

They do say you never convince scientists with the contrary opinion, you just have to wait for them to die off. I recall reading that there were still scientists who didn't believe in atoms late into the nineteenth century.

Plate tectonics didn't really become a thing until the seventies. I did a geology O-level at school in 1969 and the idea wasn't even mentioned then. About three years later, the BBC did a Nigel Calder science special, Restless Earth, that popularised the idea. (I still have the tie-in book.) I imagine it would have taken at least 20 years for the old guard to die off.

[mmcirvin.livejournal.com]

Ernst Mach held out against atomism into the 20th century. There was a kind of extreme positivism that regarded anything not directly observable (for some value of "directly observable") as a hypothesis to be avoided. The standard histories usually say that Einstein's explanation of Brownian motion in 1905 was a major turning point.

[calcinations.livejournal.com]

I disagree- from what I was told at uni and have read subsequently, Plate tectonics was the solution to the problems that they had been worrying about since the early 20th century, so by the late 60's it was agreed upon, except for stupid people who held out longer. Also school textbooks are often decades behind actual up to date research. Don't confuse public understanding of the topic with the actual professional researchers understanding.

[mindstalk.livejournal.com]

My impression from being a geology major at Caltech in the 1990s, plus further reading, was that plate tectonics was adopted quite quickly. It's a good case of how a "paradigm shifted" *without* people dying off. People resisted the old evidence of continental drift, for lack of a mechanism, then seafloor spreading data came in, and they went and looked harder for a mechanism. (That's probably simplifying work that had been going on in parallel.)

The accelerating universe went from not even being a candidate idea to accepted pretty quickly, with two teams reporting the supporting observations.

I have the impression that quantum mechanics was adopted pretty fast as well, apart from Einstein, but then all the names you hear with it are young, so I dunno.

[calcinations.livejournal.com]

If you read old textbooks, such as those by Arthur Holmes, they knew the problem, and had an idea of the solution, but Wegener's mechanism was horribly wrong, verging on the stupid, and they had nothing to replace it with, so being scientists, they had to wait until someone came up with a decent mechanism.

[maruad.livejournal.com]

I had a prof who speculated that, bearing in mind this was at least 25 years ago, that melting the arctic and antarctic ice packs could lead to increased glaciation. In fairness to him, it was an intro course on environmental studies and he was throwing out a lot of ideas and thoughts to show how many unanswered questions were still out there to be explored and studied.

[(Anonymous)]

Before orbital forcing was accepted as the principal natural driver of glacial cycles there was a theory that they were driven by an internal oscillation - warming of the oceans leads to greater snowfall at high latitudes leads to growth of icesheets leads to increased albedo leads to atmospheric cooling leads to cooling of the oceans leads to less snowfall leads to retreat of icesheets leads to decreased albedo leads to atmospheric warming leads to warming of the oceans, and round the cycle again.

I was taught this as a hypothesis in the early '70s.

As I recall, in the '90s there was concern about global warming kicking off a Scandinavian icesheet. But the climate has warmed too much for snow accumulation in Scandinavia.