The Price of Carbon

[andygates]

Rowson just had this cartoon in the Guardian. Harsh, bad taste, but on the money (enhanced European windstorms are on the climate-change track - the insurance industry were discussing this at Copenhagen last year - and these intense rain events are what they do).

Then someone pointed out that Rowson's cartoon is a riff on this classic Philip Zec cartoon of WW2. When you know that, it gets a whole lot more angry and a whole lot more bitter. And the faceless copper stops being a news story and becomes Everyman.

Comments

[ravenbait.livejournal.com]

http://www.stridingedge.net/Walks/2009/11.November/20.11.09.htm

[andygates.livejournal.com]

That's a drainage network clearly well over capacity.

Hey, you're a water boffin. When they say "thousand year event" for stuff like this, is there any maths behind that or is it just media fluff?

[ravenbait.livejournal.com]

Boscastle was a 1 in 200 year flood event. Whether this is really a 1 in 1000 I don't know. I don't imagine we have the historical data to model it accurately. If records go back no further than ten years then obviously the model will be a bit dodgy, to say the least.

But the whole idea of 1 in n year flood events is not just media hype. It's a standard measure of capacity in the sewerage network. The scary thing is that we have tended to be content with 1 in ten year flood events for design purposes, except we seem to be getting quite a lot of those.

Do a search on flood frequency analysis if you want to know more. I can't be arsed fetching my Hydrology textbooks out of the cupboards.

[ravenbait.livejournal.com]

Or take a look here. There are a number of books on hydrology and engineering on google books.

[andygates.livejournal.com]

Cheers. Presumably where the damage of a, say, hundred-year event is worse than average (say, through a city centre) the risk analysis makes it sensible to provide for less common events.

Is increased building taking the sudden rainfall capacity away?

John Freeman punches flod water back into the sky!

[flitljm.livejournal.com]

If it was Sumatra, we'd say it was the removal of all the trees from the higher slopes. I haven't heard anyone saying that for the Lakes, and the rain may well be much too generous for it to matter, but it is conventional 'ecosystem services' wisdom that hill forests reduce flooding by slowing, dispersing and transpiring the water.