Global warming?

[Happy Monkey]

Hrm.

Boston has a metro system with high energy efficiency. The trouble is, 82 percent of the energy to drive it comes from dirty fossil fuels.

By comparison, San Francisco's local railway is less energy-efficient than Boston's. But it turns out to be rather greener, as only 49 percent of the electricity is derived from fossils.

Why even make this comparison? Few people are making the choice between taking the Boston or San Francisco light rail. It's better to compare each of them with cars, which have a much higher percentage of fossil fuel usage (100% less biofuels) than even Boston. And speaking of car vs. train:

A saloon (sedan) car or even an 4x4 that is fully occupied may be responsible for less greenhouse gas per kilometer travelled per person than a suburban train that is a quarter full, the researchers calculate.

So the car has to be fully occupied before it "may" be better than the train? Two problems with that analysis come to mind. First, I don't often see a fully occupied car or 4x4. Second, the train is going anyway. If you take it instead of the car, you are increasing the train's people-moving efficiency and eliminating the car ride.

Sure, I take the underlying point of the article that there are a lot of complicating factors, but either the study's authors or the media interpreting them are reaching a bit to sensationalize it.