NPR: Global Warming is Irreversible

Climate change is essentially irreversible, according to a sobering new scientific study.

"People have imagined that if we stopped emitting carbon dioxide that the climate would go back to normal in 100 years or 200 years. What we're showing here is that's not right. It's essentially an irreversible change that will last for more than a thousand years," Solomon says.

The idea that changes will be irreversible has consequences for how we should deal with climate change. The global thermostat can't be turned down quickly once it's been turned up, so scientists say we need to proceed with more caution right now.