Even climate change skeptics agree global temperatures have risen and ice sheets are melting in the arctic and Antarctic. But they disagree that weather patterns are becoming more extreme and downplay the role of human activity on our warming planet. As Earth Day approaches, the second episode of our two-part series examines the impact of climate change not only on the planet but on people, and the debate over what to do about it.  This week, Major Garrett speaks with experts in national security, the automotive industry, and climate research.