They won't be as intimidating as a gang of Harley riders.  But they will be more earnest.  On their shoulder muscles: tattoos of Al Gore.

A group of at least 100 "Climate Riders" will be wheeling through Baltimore on Sept. 23 to raise awareness about global warming. They start out in New York City on Sept. 20, and finish in Washington DC on Sept. 24, where they plan to press their message that action is needed to reduce greenhouse gas emissions.

For information, click here. The public is free to join.

David Kroodsma, an organizer with the Climate Ride group, said that he hopes more people will start biking and walking to work because of high gasoline prices.  "It's good for the environment, because it means less global warming and air pollution. It's good for land use because when you take cars off the road, you make cities more pleasant and livable.  And there's a health benefit.  You are supposed to get a half hour of exercise a day -- and if you use walking or bicycle riding to do that, we could effectively eliminate obesity in this country at the same time we're saving an incredible amount of gas."

The downside is that millions of people -- especially in suburban areas -- are essentially stranded in areas where it's impossible to get anywhere without a car.  Try to walk to the Wal Mart to buy groceries on a hot day like yesterday, and it would be like the Bataan Death March.  Try to bike in a lot of suburban areas, and you could be run off the road, because there's no shoulder or sidewalks beside the narrow but traffic-heavy two-lane roads.

"It's really easy to bicycle in the city and in rural areas," said Kroodsma.  "But then there's that transition area in the suburbs, where we really need bike lanes."