"The report says single occupancy drivers switching their work commute to public transportation is one of the more effective ways to reduce the nation’s vehicle miles traveled while reducing harmful carbon dioxide."

Talk about stating the obvious...

I have no quarrel with the conclusion. Would anyone think driving a car doesn't produce more CO2 than riding on light rail? Does anyone think good public transportation won't improve city life?

One factor often overlooked. People riding on light rail are doing so because it is taking them where they want to go. But those in cars may be driving precisely because that light rail won't take them where they want to go.

So each rider and driver has already made some sort of analysis and chosen riding or driving for that trip.

Good point K, you also need to take a step back from individual choice to the urban and transport planning decisions that guide those choices. We can structure cities so that public transport is an attractive choice if governments choose to make public transport infrastructure a higher funding priority and if employment, services and residential dwellings are clustered closer together.

critta:

I understand what you are saying. Many believe that more tinkering and thought by various levels of government will get things right. Then the people will be happy and urbane. The cities will be 'world class' and 'vibrant'.

I don't believe it.

IMO the age of the dominant central city with a 'downtown' is passing. Cities formed because proximity allowed the most efficient exchange of ideas and goods. Technology has, or soon will, end that.

I disgree.

Lets talk reality.

Most times ofthe day you haver a multi-ton Bus, driven by a driver, and zero or only a few passengers on many routes. That is an awful real world example of the difference between theoretical and actual efficiency.

Which is why increases in ridership are so cheap in terms of CO2. There is no marginal cost if increases in ridership are to be absorbed by existing excess capacity. Once you reach the point where new capacity has to be installed, in terms of rights of way or more transit vehicles, the costs (in money and CO2) become real. Two to three people carpooling in a high MPG vehicle yields an effective 100-150 person miles per gallon, which compares well to most bus lines, and can be far more convenient.