PBS NewsHour | Clip | Weather forecasters increasingly address climate change

Even before summer began, there were extreme heat waves and new heat records throughout the Northern Hemisphere, and the forecast calls for a hotter-than-normal summer in much of the U.S. Scientists say climate change is accelerating and intensifying these kinds of heat waves. It's taken a while for some TV weathermen and women to make these connections, but that's changing. Miles O'Brien reports.