UNITED KINGDOM - MARCH 06:  An airplane lands at London City airport with Canary Wharf in the background, London, U.K., on Friday, March 6, 2009. Two thousand researchers called to Copenhagen this week to discuss the latest global-warming science will stress a growing urgency to tackle climate change, Danish Climate and Energy Minister Connie Hedegaard said.  (Photo by Chris Ratcliffe/Bloomberg via Getty Images)