Why act now? The best time to act was yesterday. The second best time is today. Every year that we don't reduce emissions represents another 55 gigatons of greenhouse gases that future generations will have to scrub out of the air. That would cost 8 trillion dollars a year, almost half the entire US economy today. And that price doesn't include the cost of people forced to move, the natural world transformed and lives lost. It's much cheaper to develop new technologies that don't emit carbon dioxide than to capture carbon dioxide that we've already emitted. Every ton of carbon dioxide we emit now imposes a burden on us and the planet, but also a debt that would have to be paid by our children and untold generations to come. The sooner we start fixing this, the easier it'll be. So do what you can where you can. Vote, change your diet and your commute, organize, plant trees, advocate for ideas, advocate for science and most importantly, advocate for action today. [Countdown Take action on climate at Countdown.ted.com]