Some good news on U.S. carbon emissions: They fell again last year. Carbon dioxide emissions from the combustion of fossil fuels used for transportation, power, industry and in our homes fell 3.4 percent in 2012, according to a report from the Energy Information Administration (EIA). In fact, they’ve fallen 12 percent since their 2007 peak, to the lowest level since 1994.
Why were carbon emissions down last year? The short answer is because we used less coal and petroleum, the most carbon-intensive fossil fuels. But there are various reasons for that decline in use.
With the latest round of international climate change talks underway in Doha this week, it’s a good time to check in on the United States’ pledge, made three years in Copenhagen, to reduce greenhouse gas emissions 17 percent below 2005 levels by 2020. Are we on track to meet that?
The short answer: Not yet. But projections depend on assumptions, so let’s look at a few recent projections.