New York Times: Two years ago, an international scientific panel seized worldwide attention by reporting that human activity was warming the planet in ways that could greatly disrupt human affairs and nature. The work of the group, the Intergovernmental Panel on Climate Change, shared the 2007 Nobel Peace Prize with former Vice President Al Gore. After two decades of delivering climate reports to the world without fanfare, it suddenly had a wide following. But as the panel gears up for its …