US greenhouse gas emissions rose 1.4 percent in 2007, compared to the previous year, the US Environmental Protection Agency reported on April 15. The report also indicates that US emissions of climate-warming gases such as carbon dioxide and methane rose 17.2 percent from 1990 to 2007.
The increase in 2007 was mainly due to a rise in carbon dioxide emissions related to fuel and energy consumption, the environmental agency said in a statement.
There was more demand for heating fuel and electricity due to cooler winter and warmer summer temperatures, compared to 2006, the report said. There was also increased demand for fossil fuels to generate electricity, coupled with a significant decrease - 14.2 percent - in hydropower generation to meet this demand.
Total emissions of the six main greenhouse gases in 2007 were equivalent to 7,150 million metric tons of carbon dioxide. These gases include carbon dioxide, methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons and sulfur hexafluoride. The EPA's report is the latest annual greenhouse gas inventory submitted to the United Nations Framework Convention on Climate Change, which sets an overall framework for intergovernmental efforts regarding climate change.