A bridge to nowhere: methane emissions and the greenhouse gas footprint of natural gas

[Baobab]

http://www.sierraclub.org/sites/www.sierraclub.org/files/sce/connecticut-chapter/Howarth 2014

In April 2011, we published the first peer-reviewed analysis of the greenhouse
gas footprint (GHG) of shale gas, concluding that the climate impact of shale
gas may be worse than that of other fossil fuels such as coal and oil because of
methane emissions. We noted the poor quality of publicly available data to sup-
port our analysis and called for further research. Our paper spurred a large
increase in research and analysis, including several new studies that have better
measured methane emissions from natural gas systems. Here, I review this new
research in the context of our 2011 paper and the fifth assessment from the
Intergovernmental Panel on Climate Change released in 2013. The best data
available now indicate that our estimates of methane emission from both shale
gas and conventional natural gas were relatively robust. Using these new, best
available data and a 20-year time period for comparing the warming potential
of methane to carbon dioxide, the conclusion stands that both shale gas and
conventional natural gas have a larger GHG than do coal or oil, for any possi-
ble use of natural gas and particularly for the primary uses of residential and
commercial heating. The 20-year time period is appropriate because of the
urgent need to reduce methane emissions over the coming 15–35 years

[tk2kewl]

1. A bridge to next quarter's profit statement