Cameron's sticking his head in the multicultural nest again and wiggling it about. Don't want to get into the wrongs and rights here, but something I've always found curious: ministers never seem to worry about the impact of people like me - students. Whether or not the just-left-home variety is better or worse than more mature chaps such as myself, we still go in and out of places en mass. Student numbers have gone from just below 350,000 a year in 1999 to near half a million now. Say we're talking about a through-put of four million students in the last decade: what impact has that had in the areas they have gone to? They pour a great deal of money in, of course, but one might argue students have also contributed to the fragmentation of existing communities and of locking out through housing price-hikes. Putnam is still my go-to guy for thinking about how the fabric of communities works: one of the foundations of social capital is staying put. In my old stomping ground, Sheffield, many students do indeed stay on. But then, what's the economic impact of that? A young, well-trained workforce competing for jobs with the locals.

This is all idle wiffle without actual research to back it up. For instance, I don't know what background inter-region migration levels are. If I'd spent more of my time doing proper geography, perhaps I would... Still, don't let that ever stop wild speculation, I say: the impact must be pretty large, given the collosal size of the population shifts. "In most respects, the sociological impacts of student versus from-outside-the-UK immigration are going to look the same." Discuss. Of course, the reason students aren't one of Cameron's punching bags - er, well, aren't more of a punching bag - would be the votes, wouldn't it?

I can't quite bring myself to seek out anyone claiming the cold proves climate change isn't happening - as if foreign weather doesn't count somehow. But I thought it worth ending the year with a quick note on two of 2010's most striking climatic occurances. The common theme emerging this year: if a complex system is changing, how do you measure when specific events mean anything? Ultimately, the answer is: for any one 'event', you can't, but you can say pretty definitively that climate change = climate disruption, and the definition of 'extreme' will shift as the variance changes.

First-off were two stories that were actually one, connected story from the summer: Russian drought and Pakistani floods. Initforthegold is as good a place as any to start with that, including a good discussion of the difference between loading the dice and changing them for ones with higher numbers. The weather underground has some good graphics showing the jetstream changes tying the two together. Russia lost a quarter of its grain crop. In Pakistan, two and a half million people were affected.

As far us freezing our asses off - it was just listening to the news, and the impact the cold is having all across Europe that prompted me to write. There's one perfect graphic for this, via Peter Sinclair's blog. The NOAA has a pretty nifty live output showing the temperature anomaly over the Northern hemisphere. Compare also to this at init: most of the total anomaly is away from the equators, towards the poles. The NOAA anomaly graph shows some spots far North that are 15 degrees celsius warmer than the 68-96 average. Spending a few moments contemplating the breadth of the difference in both directions, and having a little think about how low and high pressure work, should be enough to get across that climate change was never going to mean an even increase.

There's no real need to make any specific claims about this being 'caused by' co2-induced climate change. The important question is: can we expect this sort of disruption to increase in the future? It's not rocket science, of course: if you push a complex dynamic system with any kind of forcing, it will attempt to get back to an equilibrium. In the meantime, you get disruption - and in chaotic systems, they'll manifest themselves in all sorts of exciting ways. We already have plenty of relatively well-understand oscillations, even if their timings - like the NAO - are never predictable. It would be one thing if we could expect to get this sort of winter regularly - that's something you can prepare for. But we actually have to prepare, as much as possible, for any eventuality, since there's no exact way of knowing how the system will eventually settle.

And that's presuming, of course, we decide it might not be a good idea to carry on pushing it. The more we do, the more the regional uncertainties increase (as well as uncertainties relating to feedbacks). That's an irony that MT over at initforthegold often points out: anyone claiming that uncertainty should mean inaction hasn't understood what's happening. Or they have, and they know that doubt, however slight, is a massively appealling get-out clause that many of us would dearly love to grab with both hands.

Something for the shelf of philosophical objects...

The doughnut of empirical correctness in a theory constitutes its worth, while its hole of untruth constitutes its weakness. I regard it as a monstrous perversion of science to claim that a theory is all the better for its shortcomings; and I notice that in the luckier exact sciences, no-one dreams of making such a claim.

(Paul Samuelson in Blaug, 'The Methodology of Economics', p.97.)

Blaug does a good job of parrying that:

It is as though generations of physicists had ridiculed Newton's theory of gravity on the grounds that he committed himself to the patently unrealistic assumption that the masses of moving bodies are concentrated at their centre... Faced with the accusation that no theory with counterfactual assumptions can be taken seriously, the thesis of the irrelevance of assumptions is almost excusable. (p.104)

But mainly: new philosophical object! Almost two for the price of one, but a "hole of untruth" isn't an object, sadly.

"One day when I was a young boy on holiday in Uberwald I was walking along the bank of a stream when I saw a mother otter with her cubs. A very endearing sight, I'm sure you will agree, and even as I watched, the mother otter dived into the water and came up with a plump salmon, which she subdued and dragged on to a half-submerged log. As she ate it, while of course it was still alive, the body split and I remember to this day the sweet pinkness of its roes as they spilled out, much to the delight of the baby otters who scrambled over themselves to feed on the delicacy. One of nature's wonders, gentlemen: mother and children dining upon mother and children. And that's when I first learned about evil. It is built into the very nature of the universe. Every world spins in pain. If there is any kind of supreme being, I told myself, it is up to all of us to become his moral superior."

Lord Vetinari, Patrician of Ankh-Morpork, in Pratchett's Unseen Academicals

Often, in the moments between sleeping and waking, ideas become visceral, almost literally. This can include things like 'oh my God, Sarah Palin might be one heartbeat away from leader of the free world' or 'oh my Christ, we really are managing the fuck the one planet we have.' That last one is often accompanied by the 93 million miles between the Earth and sun shrinking so that the heavenly bodies are almost within mental grasp, almost in the same room. There really is a star blasting at us, churning our water and atmosphere.

More recently, there's been a few occasions when it's been more corporeal: yanked back from sleep and plopped into a vast dark room of consciousness, so I can have some stark fact about my physical form klaxoned at me. For some reason, my spine got that treatment (probably because of a bad back); a keen sense of bone and gristle holding my centre line together. More recently (probably after some film or other) my brain decided to get all 'aaargh' at the idea of a bullet going through it. Quite reasonable thing for it to do, one might think. The fact that usually it doesn't says something about our ability to just get on with what the world presents us with. But right then, my brain wasn't having any of it: so, here's a bullet, right? It goes through and me, this person - suddenly I'm goo, I'm all over the place.

A commenter over at Tamino's blog puts in a good word for economists:

How would you physicists like it if you had to survey a bunch of molecules to find out what they planned to do, only to have most of them change their minds anyway, and the government restructure the laws of physics because of some opinion poll?

I went to hear Nicholas Stern speak a couple of nights ago: the subject was 'after Copenhagen'. It was a great talk; the man has the gift of speaking in a way that, written down, would make excellent reading. (A skill many politicians learn early.) But I was struck most forcefully again by timescales we now now talk about: what will happen in a hundred years? Current emission rates, according to climateinteractive, give a mean of 3.9 degrees. (OK, that's 90 years...) The spread's wide: if we're lucky, closer to 3, if we're unlucky, closer to 5. It hasn't been 5 degrees above current temperatures for 55 million years. Stern had a nice turn of phrase: these are the kind of changes that move people, move deserts, and are already manifesting as season creep (discussed in this recent paper that attempts a robust framework for analysing the impacts. No model in sight there: 30 years of data.)

One hundred years. Very few humans last that long. A hundred years ago, no first world war. The Los Angeles International Air Meet showcases some crazy new designs. The first commercial air-freight flight takes place - and the first commercial dirigible flight. (Now, this many flights happen in a 24 hour period.) Albania rises up against the Ottoman empire. George V becomes king. Wow - the Vatican makes all its priests take a compulsory oath against modernism. Mark Twain dies; 1.75 billion people live on.

It turns out the past is a different planet. Let's make a prediction: a hundred years hence, it'll be a different planet again.

I'm starting this blog entry with no idea what I'm actually going to say. I've never really been sure what the purpose of this blog was. For a while it was meant to help form thoughts for what is rapidly becoming the Never-Ending PhD. Well, today, what I'll do instead is be self-indulgent. More than usual. It's my blog after all; if anyone's reading, apologies - some vaguely connected thoughts follow; they'll all loosely related by a thread of cold icy chill. One chill from telly, one from history, one from the interwebnets, and I guess there's some snow there at the end, as well as the sun being destroyed. Which is must have been, cos it's dark. No real narrative thread.

Interwebnets first: I'm on academia.edu, and it turns out that it emails you when you're googled. This is only slightly more passively narcissistic than googling oneself directly, but it's been quite alarming. It should, of course, have been obvious, but since I decided to use my own surname (rather than my old secret leftie name you'll never ever find), every blog comment or appearance I make is viewable. When someone googles 'dan olner climate change' what do they find? Having not done a thorough survey, I suspect they find someone with inconsistent views, and venting more in comments than I would consider civil. A recent google of my name + 'economics' reveals more than I knew myself about the various places I've been posting, and that my Transitionista sympathies are on clear display. This is stuff to make sociologists wet themselves; we're all seeing each other now, consensually. I don't really feel like I consented, though sticking to my own name seems an honest choice, but it does look like I've ceded privacy by default. I can't recant anything. Luckily there are no awful, drunken diatribes out there - I don't think. Who knows?

"Assuming the world doesn't end, will there come a day when all the music it's possible to write has been written? It's finite isn't it?" - Claire W, via Twitter.

Excellent question. Yes, there are a finite number of songs in the universe - with the one condition that no song can last forever. Let's make it more restrictive and say no song can last for more than 5 minutes (though we could choose 20 or 30 mins and come to the same conclusions.)

Given that, though, it turns out it might not make very much difference that its a finite number...

Obama: vp, running mate, nation, biden, girl, antichrist, berlin, birth certificate, muslim

McCain: vp, running mate, ad paris hilton, paris hilton, paris hilton ad, mccain houses, mccain celebrity, vs obama

Biden: obama, vp, senator, wife, veep, abortion, voting record, israel, quotes, family

Palin: for vp, alaska, scandal, mccain, vice president, investigation, for america