Several people have pointed out the remarkable fact that carbon
dioxide emissions from fossil fuel combustion have fallen almost
to 1995 levels. As the Institute for Energy Research noted, The
Energy information Administration reports that energy-related
carbon dioxide emissions in the United States are 2.4 percent
less in 2011 than they were in 2010, and 9.1 percent less than
in 2007 when they hit their peak level. Why are carbon dioxide
emissions on a downward trend? IER identifies the main
hypotheses for this reduction: economic recession reduces energy
use, high oil prices reduce petroleum consumption, switching
from coal to natural gas for electricity generation, and some
switching to renewables for electricity generation. At The
Atlantic, Alexis Madrigal charts out the changes over time in
the share of electricity generation coming from coal, natural
gas, and petroleum. His main point is the dramatic pace of
change in the past two years in the switch from coal to natural
gas, a pace not usually seen in