Julia P. Valentine, U.S. EPA
The U.S. Environmental Protection Agency (EPA) released its 19th annual report of overall U.S. greenhouse gas (GHG) emissions today, showing a 3.4 percent decrease in 2012 from 2011. The Inventory of U.S. Greenhouse Gas Emissions and Sinks, which is submitted annually to the Secretariat of the United Nations Framework Convention on Climate Change, presents a national-level overview of annual greenhouse gas emissions since 1990.
The major contributors to the decrease in emissions from 2011-2012 were the decrease in energy consumption across all sectors in the U.S. economy, and the decrease in carbon intensity for electricity generation due to fuel switching from coal to natural gas. Other factors included a decrease in transportation sector emissions attributed to an increase in fuel efficiency across different transportation modes and limited new demand for passenger transportation.
Greenhouse gases are the primary driver of climate change, leading to increased heat-related illnesses and deaths; worsening the air pollution that can cause asthma attacks and other respiratory problems; and expanding the ranges of disease-spreading insects. Climate change is also affecting the frequency and intensity of heat waves, droughts, and other extreme weather events.