Ice-free summers in the Arctic - tipping point reached?

[Cain]

http://www.newscientist.com/article/dn21626-arctic-sea-ice-may-have-passed-crucial-tipping-point.html

The disappearance of Arctic sea ice has crossed a "tipping point" that could soon make ice-free summers a regular feature across most of the Arctic Ocean, says a British climate scientist who is setting up an early warning system for dangerous climate tipping points.

Tim Lenton at the University of Exeter has carried out a day-by-day assessment of Arctic ice-cover data collected since satellite observation began in 1979. He presented his hotly anticipated findings for the first time at the Planet Under Pressure conference in London on Monday.

Up until 2007, sea ice systematically fluctuated between extensive cover in winter and lower cover in summer. But since then, says Lenton, the difference between winter and summer ice cover has been a million square kilometres greater than it was before, as a result of unprecedented summer melting. These observations are in contrast to what models predict should have happened.

This could trigger landslides on steep submarine slopes in the area, unleashing tsunamis capable of hitting the UK, and releasing buried methane that could amplify global warming. Something similar happened off Norway 8000 years ago in a similar geological setting, Nisbet told New Scientist.

A lot of climate "tipping points" and thresholds seem to have been reached in the past few years, such as this report from a couple of years back.  I also recall a more recent report suggesting that climate scientists believed we had reached the point of no return in regards to a two degrees rise in global temperatures, which is definitely not good (though, at least, surviviable.  It does reduce our threshold for managing further, more catastrophic increases, however.  4 degrees and above rises could end up destroying society as we know it).

This also opens the possibility of Arctic geopolitical rivalry, a theme that has been raised in some corners over the past few years.  Ice-free summers would allow for greater trade in the region, but also increase the possibility of mineral exploration and exploitation - such as gas and oil.  Given a strong American, Canadian, Scandanavian and Russian presence in the region, things could get interesting.

[Triple Zero]

Well, crap.

All the other things seem kind of trivial when you contrast it with "the end of society as we know it", you know? Especially when "managing" this issue (as far as even possible) will become even harder with the overpopulation we're going to face (plus the real possibility of some pandemic hitting hard) ... did I forget any?

Makes me wonder what our odds are of making it to the 2100s. Of course you can't put real odds on that because of unpredictability etc, but the fact that it's not "probably fine, unless some unforeseen event" but instead there's some pretty well foreseen events that we need to tackle.

Well, at least it seems we're really making some good progress with solar and wind power. Efficiency-wise, at least. We "just" need a smart grid to even out the fluctuations and of course change the whole infrastructure. Piece of cake! Oh and it appears they came up with some radical new type of nuclear reactor fundamentally different than the ones we're using now, in that it cannot have a melt-down (it just doesn't work that way) and generates no or hardly any nuclear waste at all. I think it was on a TED talk. But I don't know in how much it is highly optimistic marketing speek.

[Cain]

I seem to recall a climatologist giving us a roughly 50/50 chance of making it to 2100.  Personally, I felt he might be overstating the cause, but I suppose there is a tipping point for global warming, after which you get cascading effects.

I'm sure humanity would survive, at least in part up to six degrees, but when you consider four degrees is enough to turn England, a land where it rains for six months, and the next sixth months is all the water dripping down from the trees, into the Sahara, the idea that the vast majority of humanity would continue to exist, in anything approaching the comfort which we currently enjoy, is clearly not tenable.

New nuclear reactor sounds interesting.  Well, even if we reconfigure our entire infrastructure to run off renewable and nuclear energy, we still need the oil, because plastics and stuff.  But it certainly wouldn't hurt, and would likely help the situation a lot.

[Triple Zero]

Yeah, there's "humanity" and "humanity as we know it".

How much of the oil is spend on plastics and how much on energy, then? I supposed the vast majority is spent as energy?

[Cain]

A quick google suggests at least 8% is used in manufacture of plastic goods and in agriculture.

So a not insignificant amount, but nowhere near a majority.  And since we'll need oil for those kind of things for a while yet, whereas we do have replacement fuels, it would certainly be a good idea to switch over now, and conserve as much oil as possible until we can figure out replacements for the non-energy uses.

Which is, of course, why we won't do it.

[navkat]

LALALALALALALALA! I CAN'T HEAR YOU! I'M NOT EVEN LISTENING! LALALALLALALALALALA!

[Kai]

I really don't have anything to add to this, except, thank goodness humans are only a blip on the geologic time scale. It may take 4 million years, but continental ecology will turn back around. I mean, this won't be anywhere near the Great Dying in catastrophe, but will definitely set back planetary life for a while. Could be K-T scale extinctions.

Yes, I look at this in a positive light, despite it all being horrendously pessimistic. I have zero control over these planet scale issues, my personal input being so minor as to be ignorable. So I'm gearing up for a long haul, with aim to at least preserve some of our biological and cultural heritage in the mean time. And, assuming some humans survive, there could be a quite amazing future beyond the mess.

[Mesozoic Mister Nigel]

I'm a little invested in the idea of our survival as a species. I mean, I think humans are pretty cool and interesting, and it would be a shame for the species to be lost.

The fact that we have an active hand in striving for our own destruction is very sad and frustrating, especially when we're operating counter to our own best interests in hot pursuit of something completely stupid - the accumulation of the most symbolic representations of pieces of food.

It's a little like arguing to win, regardless of the truth, at the expense of all your friendships.

[Mesozoic Mister Nigel]

Of course, I'd also like to see an analysis from a source besides the Weekly World News of science. Not that it isn't a dire situation, but I'd be interested in a credible climatologist's take on it.

[Cain]

I'm having trouble finding other reports, but Tim Lenton does, at the very least, seem to have a level of expertise in the subject (he has advised the British government on the arctic and global warming before, and his use of rigorous modelling methods is encouraging), and his argument is backed up by recent reporting on the Arctic

http://www.guardian.co.uk/environment/2012/mar/14/met-office-arctic-sea-ice-loss-winter
http://www.telegraph.co.uk/earth/environment/globalwarming/8877491/Arctic-sea-ice-to-melt-by-2015.html
http://www.guardian.co.uk/environment/2011/oct/03/arctic-ozone-layer-hole-expands

[Kai]

I'm a little invested in the idea of our survival as a species. I mean, I think humans are pretty cool and interesting, and it would be a shame for the species to be lost.

The fact that we have an active hand in striving for our own destruction is very sad and frustrating, especially when we're operating counter to our own best interests in hot pursuit of something completely stupid - the accumulation of the most symbolic representations of pieces of food.

It's a little like arguing to win, regardless of the truth, at the expense of all your friendships.

I find only a few scenarios that would actually kill all humans. Most of them center around aerial transmission of unstoppable pathogens, but even then (with 7 billion people on the planet) it is very unlikely some people would not have immunity. A nice factor of large populations. Everything else may put a huge dent in numbers, but will inevitably be countered by technology, whether 'primitive' or futurist. We have a nice edge over just about any other species out there, in our abilities as a tool using generalist omnivore.

Right now, there is literally no fear humans are going extinct. We aren't suffering a fertility crisis, and our population increases continue to be exponential. Get back to me after we hit carrying capacity and things start to crash.