So California 
is taking the American lead in trying to do something about global warming. Pretty dang cool.
California will become the first state in the country to require industries to lower greenhouse gas emissions under a deal struck Wednesday by Gov. Arnold Schwarzenegger and Democrats that could dramatically reshape the state’s economy…. By 2020, when industries would have to lower carbon dioxide and other greenhouse gases by 25 percent, solar panels, alternative fuels and electric cars could be commonplace, according to advocates of the legislation.
The plan is to use tradable emission permits, at least tentatively.
The board is likely to set up a trading system that will allow companies to buy and sell emission credits, which would allow a company that made more emission reductions than required to sell credits to another business that hasn’t reached its emission goal…. The governor also demanded that the bill require that a trading system be created to help industries meet the targets. While the final version of the legislation points the way toward a trading system, some argued it was not specifically required and that the governor did not get what he wanted. British Petroleum announced late Wednesday it would not support the bill because it seemed unclear as to whether a trading system would actually develop.
So first thing to do is say, “yahoo! Some good news!”
The next thing to do is be wary of a cap-and-trade system for carbon. Cap-and-trade can work quite well in reducing pollution, as is evidenced in the experience of sulphur and nitrogen oxides 
. However, to work, a system like this needs to have measurable emissions. For sulpher dioxide, the emissions were mostly coming from large industrial facilities, especially coal-fired electricity power plants. It was pretty easy to put a meter on the smokestack to measure how much SO2 was coming out, and then check to see if the facility had the necessary permits to cover their emissions.
But carbon doesn’t strike me as easy to enforce. I suppose for large facilities burning fossil fuels, they can submit records of their coal, oil, and natural gas purchases, and those numbers can be converted into estimated carbon emissions. You can’t do that for transportation, though, at least no way that I can think of off the bat. Maybe California will ignore transportation. Anyway, we’ll see.
PS: Broken Flowers 
is a great movie. Oddball and funny. One of Jim Jarmusch’s best.