Population "stability" isn't enough, the earth is already overpopulated with humans. They're destroying essential tropical rain forests, polluting and crapping on the environment and driving the mass extinctions of other species. Add to that bad land usage with chemical fertilizers and pesticides and animal farming and you have a crisis on your hands.
As John Kerry and Arnold said, climate change isn't a strong enough argument to convince most people- they dont care what's going on in the Arctic and dont care about sea level rises unless they live near a coastline. You need to use the pollution argument- look at how polluted the air in Delhi, India is (as an example.) There is a strong pollution argument to be made for why to stop using fossil fuels.