Last month, the administration’s Energy Information Agency reported that carbon dioxide emissions from burning fossil fuels in the United States have fallen by almost 9 percent since 2005.
The forecast for 2020, assuming a continuation of current policies, is that emissions will be about 10 percent below 2005 levels, in sharp contrast to the 25 percent increase forecast just a few years ago. We are still a long way from stabilizing the level of carbon dioxide in the atmosphere, but increased efficiency of our energy use appears to be paying off.
Despite the growth in our economy, it is worrisome that our declining emissions of CO2 may largely stem from shifting our manufacturing to China and other nations. About 17% of the goods and services that we consume in the United States result in carbon dioxide emissions elsewhere in the world. For instance, China’s CO2 emissions grew by about 9% while ours were declining.
Since CO2 has a 5 year lifetime in Earth’s atmosphere, it is well mixed around the planet. Thus, a CO2 molecule emitted from a factory in Beijing has the same global warming potential as a molecule emitted in Boston.
We still have a long way to go to implement effective policies that will slow or prevent global climate change. Our falling emissions are a good start, but increased efficiency of use, alternative—non-fossil energy, and more recycling of waste products will be needed to mitigate CO2 emissions from our increasing consumption of goods—many of which are produced outside our borders.
Web Link
http://www.pnas.org/content/108/45/18554.full.pdf+html
Photo, taken on April 5, 2011, courtesy of Flickr.