Cold weather drives people to turn up the thermostat, and that's exactly what happened during the winter of 2013 across the U.S. Northeast. As a result, the United States experienced a 2.5 percent increase in carbon emissions over the previous year, according to the U.S. Energy Information Administration (EIA).
In its recent annual CO2 emissions report, the EIA said only three years since 1990 have seen bigger annual increases: 1996, 2000 and 2010. In 2013, the agency said, the number of "heating degree days," when more energy is required to heat a building, were up by 18.5 percent over 2012.
The report said the size of the increase in toxic emissions wasn't the result of a policy failure in Washington, which has worked to reduce emissions.
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Instead, a major reason for the increase was that 2012 was the warmest year on record in the United States, EIA analyst Perry Lindstrom told Climate Central. "2012 was so warm, and then 2013 started returning to normal on its way to a chilly winter when you got to the end of the year."
Further, according to an EIA chart, carbon pollution from increased energy use was lower than in 2007, when the nation's emissions were the highest on record.
The EIA analyzed the numbers this way: Carbon emission from energy generation totaled 5.9 billion metric tons in 2005, then reached its highest level on record - 6 billion metric tons - in 2007. By 2012, though, the level dropped to just under 5.3 billion metric tons, the lowest in 18 years. Then came the spike of 2013, caused by bitter cold, which rose the emissions to nearly 5.4 billion tons.
To make it personal, energy for homes - not office buildings, but only homes - generated 16 percent more carbon in 2013 than in 2012.
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Despite the carbon spike of 2013, what's known as the U.S. economy's "carbon intensity" was unchanged from the previous year. Carbon intensity gauges how much CO2 is emitted per unit of gross domestic product.
In both years, the EIA reported, the United States released 343 metric tons of carbon for every $1 million in GDP. And in 2012, U.S. carbon intensity fell by 6.5 percent compared with 2011, the most since the government began keeping such records in 1949. The reason is that cleaner-burning natural gas has been gradually replacing coal to generate electricity.
What all this means for the future is hard to say, according to Lindstrom. He said many factors beyond those contributing to the emission spike of 2013 will affect carbon releases in the long term. Yet he says he's confident that increased fuel efficiency and use of renewable sources of energy are bound to lead to ever-decreasing emissions.
By Andy Tully of Oilprice.com
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Andy Tully is a veteran news reporter who is now the news editor for Oilprice.com More