Hurrah: Copenhagen dampens banks’ green commitment

Says the Grauniad. Not the “Hurrah”, I added that. The Grauniad doesn’t come out for it being good or bad news. But I think it is. Emissions trading is a waste of time and an enormous waste of money, promoted mostly by those who hope to get rich on it.

Carbon Tax Now.

My previous post refers.

How I found glaring errors in Einstein’s calculations?

Three posts in one day. And all of such high quality. You lucky people.

Pascal has a go at explaining the std.nutters. Some of it is the usual correct stuff, but some of it is wrong: What you need, over and above all that, is constant social interaction with other practising scientists. Oral tradition and daily exposure to other scientists’ everyday decisions are indispensable. That sounds fairly plausible, doesn’t it? Until you think of Newton. Or indeed, of Einstein.

Sea ice again?

At some point I need to decide if I’ll re-start the by-now-traditional sea ice bet for the summer. Before we start arguing over the details, remember that there is a lot of inter-annual variablity so we need to disagree *a lot* to have a meaningful bet. But at least one person has said in the comments that they feel “worried” by this years ice, so that suggests pessimism that I can exploit!

Any thoughts about what you might want to bet about, please leave a comment. My default position is going to be “will fit the 1979-2009 slope extrapolated to 2010”. Bear in mind that this isn’t a forecast – it is some kind of rough idea. If I frecall, RMG thought ~0.5 Msqkm was about the right uncertainty.

Oh, and here is a pointer to http://www.ijis.iarc.uaf.edu/en/home/seaice_extent.htm to get you started.

Airbourne fraction, again

This was an ask stoat question, and probably a fairly easy one, so I’ll have a go.

First of all, what is it? AF (ie, Airbo(u)rne Fraction, is the proportion of human emitted CO2 that stays in the atmosphere, the rest being sunk in land or ocean. Now it is important not to confuse the “proportion that stays in the atmosphere” with “the concentration in the atmosphere” otherwise you get silly little skeptics running around thinking that “airbourne fraction is constant” means that CO2 has stopped increasing. Sigh. However, I see that last time I looked at this I was having to slap down the other side who seemed to think that AF was rapidly rising to 100%. Sigh #2.

Having poked around a bit after the recent Knorr paper, I find that skeptical science seems to have done a pretty good job on the story in general, so I don’t think there is any need to explain that side much more (or, you can have mt and Eli). But since I’ve started this post I’d better find something to say. And that is… two things:

First off, there does seem to be some “pressure” to find increasing AF. That it should increase doesn’t seem to be a strong scientific prediction, but it wouldn’t be very surprising given increasing human emissions and possible degredation of sinks. And if it was increasing, that make future CO2 predictions more exciting. Which brings me on to the second point:

As someone commented, AF itself isn’t a very physical variable. The real physical variables are the sources and the sinks. What we can measure fairly easily are sources (fossil fuel use well; deforestation harder) and the concentration. From those you can compute the sinks and the AF. Or you can try to estimate the sinks directly but that is imprecise. But now suppose you need to predict *future* CO2 levels (and if you want to project future climate change, you do need to). You can run your economic models forwards and deduce emissions, but modelling the sinks is hard (you can stuff them all into a coupled GCM with carbon model, and the Hadley folk at least can do that, but I’m not sure how accurate it is thought to be). So it is an awful lot easier just to use the constant scaling factor of AF to deduce future CO2 levels. And so you have this “tuning knob” and what value should it be? Since AF ~ 0.5, I think most people use a half, which seems about fair – you don’t know its future value accurately, but then you’re guessing at the emissions too, so it all washes out togther. But of course, if you knew that AF was going up, you could get to higher CO2 levels earlier. That would be bad, wouldn’t it?

[Update: per L in the comment “Some folks talk about GHGs running away a bit, what with all the forest fires and permafrost melting — this would also show up as an increased AF, wouldn’t it”. More easily, it would show up as yet another thing you can measure, the year-by-year change in CO2 levels. Which was what the earlier post, and its graph, was about. Which shows that nothing too wildly exciting is occurring.

ps: we’re up to comment ~9,800. Nearly at the majic 10k, for which there will be a Prize! -W]

Himalayan glaciers to disappear by… when?

Reader enragedparrot asks the rather sensible question, which appears to have been somewhat neglected in the vast war of words of 2035, 2350, and quite what is the source for what: if 2035 is badly wrong, what is the right date?

The answer, of course, is that I don’t know. But I may be able to tell you something useful along the way. If you’ve seen a better answer, please point me at it.

[Dragged from the comments: http://web.hwr.arizona.edu/~gleonard/2009Dec-FallAGU-Soot-PressConference-Backgrounder-Kargel.pdf is excellent -W]
Continue reading “Himalayan glaciers to disappear by… when?”