William Nordhaus (Yale University) who is the guru of carbon taxation and the economic effects thereof (one of), has switched to advocating a 'global Pigovian Carbon Tax'
(with revenue neutrality: ie the entire tax is rebated back through the tax system)

on the grounds that the traded permit system has failed to date (Kyoto implementation) and also the size of financial flows between countries is unrealistic (US will never stump up).

A third (key) factor is that the incentive to cheat is too high-- even in a 'good governance' environment like the US and US, let alone Russia or some other country.

When I read that the second or third largest illegal commodity in the US (after cocaine and marijuana) was CFCs smuggled in from countries still allowed to make them, I have some sympathy with that view.

Fish quotas: glad to know it's working.

The Canadian experience has soured me, though. White man exploited cod in the North Atlantic happily for 700 years, and the natives for thousands of years before that.

The cod is now gone, and shows no sign of ever returning-- the population has dropped below self sustaining

From what I understand this week, if we don't ban cod fishing in British waters, the same is sure to happen here.

When European governments refuse to go with scientific advice on allowable fish catches, I despair.  It's a parallel to the Global Warming situation: politics dampens down the scientific conclusions.  Politics drives science, rather than the other way around.