Global warming felt by space junk, satellites -  NBC News

Cooling the upper atmosphere causes it to contract, exerting less drag on satellites. Atmospheric drag can have catastrophic effects on items in space — for instance, greater-than-expected solar activity heated the outer atmosphere, increasing drag on Skylab, the first U.S. space station, causing it to crash back to Earth.

Richard Muller and Mitch Daniels: The Fracker's Guide to a Greener World - WSJ.com

China's coal use grows at about 50 gigawatts per year, or 200 times faster than its solar growth