ClimateBiz: The day before the U.S. Environmental Protection Agency begins hearings on its decision to prevent California from regulating tailpipe greenhouse gas emissions, global agencies called on automakers around the world to boost fuel economy by 50 percent to fight climate change. The International Energy Agency, United Nations Environment Programme, International Transport Forum and FIA Foundation unveiled the ’50 by 50′ Global Fuel Economy Initiative (GFEI) at the Geneva Motor Show on …