A few further thoughts:

the biggest problem that the human race has right now with regards to ALL of the "environment" issues we will be facing in coming years is overpopulation.

There are simply too many people for this world to support, and we are fast running out of resources. Food, housing, health care, energy, and clean water aren't infinite, and if we keep reproducing the way that we are, we're going to run into "deer herd without natural predators" syndrome.

It's not going to be fun a few decades from now when billions of people across the globe look to Canada, the US, and Brazil, and ask themselves "what gives THEM the right to those resources?". It's going to be even less fun when neighbors are doing the same thing at home, because as a nation we are already surpassing sustainable capacity, but still growing. Mass famine, thirst, disease, and death will undo thousands of years of social progress in a very short time. A group of people that can't feed themselves won't be able to have any kind of health care or education for future generations, and will doom them without any kind of outside intervention.

I'd like to be able to ask everyone in the world to please consider that issue before having that second, third, or nineteenth child. It's not only irresponsible and greedy, but potentially damaging to the future of our species. However, that doesn't seem to be very PC these days.