The arm of the US Dept of Energy that tracks GHG emissions has come out with final numbers for 2009 emissions. Turns out that last year saw the largest absolute and percentage drop in US CO2 emissions since we began tracking the numbers decades ago. The EIA’s report is here. Here’s a key graph illustrating the decrease:
One way to think about these numbers is in relation to the emissions reduction goal embraced by the House-passed ACES bill and the U.S. Copenhagen Accord pledge, both of which aim to reduce US GHG emissions to 17% below 2005 levels by 2020. This latest analysis shows that by 2009 we’d already achieved over half of this goal, getting down to about 10% below 2005 levels.
Of course, much of this decrease results from economic contraction — but perhaps not as much as you’d think. The EIA report includes an interesting analysis of the relative roles of increasing energy efficiency, fuel switching (mostly from coal to the relatively cleaner natural gas), and GDP contraction, aka the recession. The recession plays a large role but not a dominant one, as discussed well by Joe Romm in a Climate Progress post here. EIA’s conclusion: “These three factors (GDP, energy intensity, and carbon intensity) combined in roughly equal proportions to cause emissions to fall by 7.0 percent.”