This figure shows the trend in U.S. greenhouse gas emissions between 1990 and 2010. Emissions increased by 10.5 percent between 1990 and 2010.
Greenhouse gas emissions declined in 2008 and 2009 for two main reasons:
- A larger share of electricity was generated with natural gas (and to a much lesser extent renewable energy). This offset coal-fired electricity generation, which emits about two times the amount of carbon dioxide (a greenhouse gas) as natural gas-fired electricity generation per unit of electric energy.
- Economic activity decreased during the Great Recession, which ran from December 2007 until June 2009.
Emissions increased 3.1 percent from 2009 to 2010, as economic growth returned to the United States.
Source: Inventory of U.S. Greenhouse Gas Emissions and Sinks 1990-2010 (EPA 2012)