WASHINGTON U.S. greenhouse gas emissions fell nearly 10 percent from 2005 to 2012, more than halfway toward the United States' 2020 target pledged at United Nations climate talks, according to the latest national emissions inventory.
The report showed that emissions dropped 3.4 percent from 2012 to 2011, mostly due to a decrease in energy consumption and fuel switching from coal to natural gas.
The Environmental Protection Agency on Tuesday published the United States' 19th annual emissions tally to the U.N. Framework Convention on Climate Change.
The United States uses 2005 pollution levels as its benchmark to measure emissions cuts, and has a target to lower emissions by 17 percent from that starting point by 2020.
Since 1990, the first year the United States kept the inventory, carbon dioxide emissions - largely energy-related emissions and the most prevalent greenhouse gas - rose just 5.4 percent.
Meanwhile hydrofluorocarbons (HFCs), super greenhouse gases used primarily as refrigerants, saw a dramatic rise of over 309 percent.
The Obama administration has taken steps to reduce these emissions through bilateral and multilateral agreements with major polluters, including China, the world's biggest greenhouse gas emitter, and India.
The EPA prepares the annual report in collaboration with other federal agencies and is subject to public comments.
A United Nations report released Sunday said that governments must act faster to keep global warming in check and that a radical shift from fossil fuels to low-carbon energy such as wind, solar or nuclear power would shave only about 0.06 of a percentage point a year off world economic growth.
The report, endorsed by governments, is meant as the main scientific guide for nations working on a U.N. deal to be agreed in late 2015 to rein in greenhouse gas emissions that have hit repeated highs this century, led by China's industrial growth.
The Obama administration's climate action plan, now being implemented, is expected to steer the United States to meet its 17 percent target by 2020.