Is This Climate Change?

There have always been episodes of extreme weather, and there is no way to know whether global warming has made it worse. On the other hand, some scientists argue that storms like Nargis are more likely in a warming world. Al Gore was careful with his words, but he said as much this week when he reportedly told NPR radio in the US: "We're seeing consequences that scientists have long predicted might be associated with continued global warming." A similar debate followed Hurricane Katrina in 2005. Some scientists said that warmer seas could make such storms more intense, though not more frequent. Last year's reports from the Intergovernmental Panel on Climate Change said it was "likely" that future cyclones would be more intense. Since then, however, research has shown a fuzzier picture, with future storm strength increasing in places but decreasing in others.