Al Gore speaks at TED. Great video comparing Earth and Venus and why carbon dioxide is a real problem. He also speaks about us being a generation that can rise to the occasion, to tackle the Global Climate Change, and that we should do it with joy and pride.

Earth and Venus are exactly the same size [...] and have exactly the same amount of carbon. The difference is on Earth most of the carbon has been leached over time out of the atmosphere, deposited in the ground as coal, oil, natural gas etc. On Venus most of it is in the atmosphere. The difference is that our temperature is 59 F degrees on average, on Venus it's 855 F. This is relevant to our current strategy of taking as much carbon out of the ground as quickly as possible and putting it into the atmosphere.