"US carbon emissions fell in 2012 – again – after peaking in 2007. The Great Recession and a boom in cleaner natural gas are widely credited as driving the reduction, but broader, longer-term shifts are also changing the way Americans use energy."
"The US economy is expanding. Population is growing. But carbon emissions continue to decline.
That's the good news. If the trend continues, it would suggest that post-industrial nations can grow while keeping emissions in check. The bad news is that the reduction is limited to the United States whereas the threat of increasing global emissions is global.
Energy-related carbon emissions in the US dropped 3.8 percent in 2012 to levels not seen in 18 years, according to a report released Monday by the US Energy Information Administration (EIA). It's the second largest annual decrease in carbon emissions since 1990, behind the recession year of 2009, and it happened in a year where gross domestic product grew by 2.8 percent and population grew by 0.7 percent."