Cars are not the problem, there is no one thing that is the problem. Simply being alive and doing things uses energy, there is no way around that.
And BTW if you do the math a bicyclist (in the US, eating a typical US diet) emits more CO2 per mile than a small car. Assumptions: The bicyclist is riding in addition to any exercise, the riding is not exercise, and the bicyclist eats normal food. A bicyclist who prefers organic, or local, would definitely emit more (both of those emit more CO2 in the growing than regular food).
It's a surprising result, I know. But it's because humans are not very efficient in turning food energy into miles, and cars are reasonably efficient. It doesn't help that growing food takes a lot of energy, especially if you force yourself to only eat local, if you do that energy really goes up.
I would be rather wary of bike endorsing studies posted on sites called "bikesomething" just as I would be wary of "rightwingnut.com" publishing studies on immigration or any other contentious issue.
What about CO2 emitted by the driver? They are respiring too.
The real issue with emitted CO2 is not the quantity at the exhaust-pipe versus the quantity exhaled by a cyclist. The CO2 emitted by the cyclist was absorbed by plants in the preceding months. The CO2 emitted by the car was absorbed by plants in a previous era of the earth. The cyclist allows you to leave the oil in the ground keeping the contained carbon out of the atmosphere.
You misunderstand. It's not the CO2 of the plants that are eaten, but the heavy equipment necessary to grow the food, the tractors, and everything else involved in growing food.
That's why produce is so expensive - it takes a LOT of energy to grow it.
Produce is expensive because it's minimally subsidized and it takes a lot of people, land, and care instead of a lot of energy. Dry corn is extremely hardy, fresh lettuce wilts.
At the extreme end, roses are not actually much plant matter, they are expensive in large part because you can't treat them like bricks. On that continuum Produce is closer to flower than grains.
> And BTW if you do the math a bicyclist (in the US, eating a typical US diet) emits more CO2 per mile than a small car. Assumptions: The bicyclist is riding in addition to any exercise, the riding is not exercise, and the bicyclist eats normal food. A bicyclist who prefers organic, or local, would definitely emit more (both of those emit more CO2 in the growing than regular food).
This result is useless since it makes impression that those miles are interchangeable while they are not. No bicyclist will make same amount of miles per unit of time as car driver. Bicyclist will make other choices: living closer to the job, working remotely, etc.
Cars are not the problem, there is no one thing that is the problem. Simply being alive and doing things uses energy, there is no way around that.
And BTW if you do the math a bicyclist (in the US, eating a typical US diet) emits more CO2 per mile than a small car. Assumptions: The bicyclist is riding in addition to any exercise, the riding is not exercise, and the bicyclist eats normal food. A bicyclist who prefers organic, or local, would definitely emit more (both of those emit more CO2 in the growing than regular food).
It's a surprising result, I know. But it's because humans are not very efficient in turning food energy into miles, and cars are reasonably efficient. It doesn't help that growing food takes a lot of energy, especially if you force yourself to only eat local, if you do that energy really goes up.