The sky is not falling. It's just heating up. A little. The trouble is that on a planet of such exquisite interdependence--where a degree's difference in average air temperature can be enough to cause grasslands to grow instead of forests and a degree's difference in water temperature can tip the scales against salmon racing their biological clocks to the sea--a little heating goes a long way. John Ryan explains climate change--the causes, the impacts, the solutions--from a Northwest perspective. The bad news is that Northwesterners generate more than their body weight in greenhouse gases every day. The good news is that we have the technology and the smarts to make better choices for our climate.