National Public Radio: There has been a lot of extreme weather in the Northern Hemisphere this year, including the recent torrential rains in Colorado, flooding in Europe, bitter cold in Florida and a heat wave in Alaska. And scientists say all of it is related to some odd behavior by the powerful air currents called the polar jet stream.
The jet stream is "this ribbon of very fast moving winds that's high over our heads," says Jennifer Francis, a research scientist at the Institute of Marine & Coastal Sciences at Rutgers...