In the summer of 2007, the G-8 nations (Britain, Canada, France, Germany, Italy, Japan, Russia, and the United States) met at a summit. With an eye on the 2012 expiration of the Kyoto Protocol, German Chancellor Angela Merkel and Japanese Prime Minister Shinzo Abe, leaders of the third and second largest world economies, pressed the leader of the larg- est, George W. Bush, to join them in strengthening an international response to climate change. Pointing to a U.N. report joined by more than 2,000 scientists estimating that, to prevent global temperatures from spiking to disastrous levels, greenhouse gases would have to be drastically limited within eight years, they argued that the developed nations should agree to set specific targets-such as a 50 percent cut in emissions by 2050. President Bush for years had been publicly skeptical of the science of global climate change, challenging the no- tion that it was caused by human activity, and had led U.S. resistance to signing the Kyoto Protocol. But in June 2007 he altered his approach somewhat. While acknowledging the im- portance of addressing climate change, he would draw the line at accepting specific targets for reducing greenhouse gas emissions. Instead, he called for a meeting of the most polluting nations, with the goal of crafting a plan for reducing-not capping-emissions.

What happened? Have the world's heaviest polluters, including top polluter the United States, been able to reach an agreement? Have fast-developing nations like China and India signed on? Will the developed countries help them with new green technologies?