I think a major contributor to climate change is the amount of traffic in cities, and how in a lot of places it feels like a car is required to be able to go anywhere. A factor contributing to that is how little cities do to make transportation methods like biking accessible and safe. There are a lot of roads where there is not a bike lane and there is barely any space provided for bikes. At best, a bike has to use the side of the road, which is very narrow and usually contains garbage bins, parked cars, and other obstructions, and at worst there is no room for a bike on the road, and bikers have to use the unpaved terrain just off of the road to avoid getting hit by a car. I personally have biked on some roads where I had to use unpaved and uneven terrain on the side of the road and not only is it inconvenient, it is not safe at all and heavily discourages biking, which is one of the most efficient carbon neutral transportation methods.