A blog like this one is about the environment anyway, in its own way. By not driving and not using gasoline, cyclists don't put out any greenhouse gases or pollution. So instead of talking about cycling, per se, I'm going to talk about pollution. In particular, I'm going to talk about air pollution.
Cyclists have to put up with a lot of stuff on their rides each day. Traffic, poorly-kept roads and shoulders, people who think they belong on the sidewalk, cell-phone-using drivers who don't pay attention to the road, etc. But the part of the equation that isn't considered nearly enough is the effect of auto exhaust on the cyclists' health.
Here's an old article about air pollution as the cause of diminished lung capacity in children.
Here's one about air pollution as a major cause of lung cancer.
Here's one about the various pollutants that can be found in auto exhaust.
And here's one about diesel exhaust as linked to cancer, asthma, and other ailments.
It constantly amazes me that the auto industry is given free rein to pollute all over us, make our health deteriorate, and throw global warming-causing pollution into the air, yet no one seems willing to do anything about it. Oh, sure, they build hybrid cars and widen roads and the like to try to relieve it, but these steps don't work.
People simply drive hybrid cars more because they think they can, and the amount of matter poured into the air by these vehicles isn't lessened at all. And widening roads, far from supposely decreasing air pollution by decreasing the amount of time cars are on the road, actually encourages more cars to be on the road, making the problems worse (and not only for pollution: congestion becomes worse due to this failed solution).
The figure of 43,000 deaths per year on our road system is only for accidents. There's no count for the number of deaths due to extended exposure to this toxic mess we encounter each day. And it's getting worse all over the world.
Not every one "believes" in global warming. But the same tactics used to combat global warming (and I mean REALLY combat it, not just control its growth via things like carbon taxes and pollution credits trading) will help to clean up the air so that we can all breathe more freely and healthily. So it really doesn't matter if you're trying to fight global warming or not - you're still making the world a better place by getting out of your car, onto a bike, and pedaling instead of driving.
So get rid of your car. Get a good bike. Ride it. See how your life improves. And know that you're doing your part to improve life for everyone around you.
People, not speed.