Don't take this as an environmental piece. But, it kind of is.
In the back of my mind, I wonder if the Earth is trying to kill us off. Consider the following items:
Global warming causes water to rise. People drown.
More hurricanes, stronger storms are coming around. More people get killed.
Not sure where I'm going with this one, but there is a balance on the earth with the number of people and the Earth. If there are too many, the scale overcorrects itself.
Maybe if it tips back too far the other way, an ice age occurs?
Well, food for thought anyway.