The United States and China are pledging to move faster to reduce or limit emissions of heat-trapping gases blamed for global warming. China and the U.S. are the world's two largest polluters, and by taking action together, leaders from both countries hope to spur other nations to be equally aggressive as they work to finalize a worldwide climate treaty next year.
What both countries are announcing, according to the White House:
—Reduce U.S. greenhouse gas emissions by 26 percent to 28 percent by the year 2025, compared to what the U.S. was emitting in 2005. Previously, Obama had committed to cutting emissions by 17 percent by 2020 compared to 2005 levels, and officials say the U.S. is on track to meet that goal.
—Double the rate at which the U.S. is reducing its emissions per year. Between 2005 and 2020, the U.S. on average must cut emissions 1.2 percent per year to meet Obama's overall goal of 17 percent. Over the five years between 2020 and 2025, the U.S. aims to reduce emissions and average of 2.3 percent to 2.8 percent per year.
—Submit the new 2025 emissions reduction target by the end of the first quarter of 2015 as the intended U.S. contribution to the U.N. Framework Convention on Climate Change, the treaty that nations hope to finalize later in 2015 in Paris.
—Set a target for carbon dioxide emissions to peak by around 2030, with the goal of topping out earlier if possible.
—Expand the share of China's energy consumption derived from zero-emission sources to about 20 percent by 2030. The U.S. says that would require China to develop up to 1,000 gigawatts of new power from sources like nuclear, wind and solar.