The earth and life on it will go on in spite of what people do. The earth and its climate have been constantly changing throughout its history with life enduring through all of it. Our planet has been ice covered from pole to pole at least twice in its history and yet for a good portion of the time since earth's formation global temperatures have been warmer than today. There have been several global extinction events that wiped out a large percentage of all living things. Life on earth endures, changes and adapts. We may go extinct but no matter how badly people mess things up life will overcome it all eventually.