Robert Howarth, a Cornell University professor of ecology and environmental biology, along with two other Cornell professors, Renee Santoro and Tony Ingraffea, have just published a new peer-reviewed study in the journal Climate Change titled, “Methane and the greenhouse-gas footprint of natural gas from shale formations.” The study evaluates natural gas from shale compared with other energy sources with respect to how much “greenhouse gases” are created during the extraction process. The study makes the claim that shale gas extraction is actually worse for the environment than burning coal because of greenhouse gases.
This newly published paper in a peer-reviewed journal is big news and has already been covered in the mainstream media echo chamber with more than 300 articles. But the criticisms have also been swift.
Man-caused global warming itself is a controversial theory and the basis on which the study was done. Supposing we accept man-caused global warming for the sake of argument, the primary points the study makes are:
- A lot of methane (natural gas) escapes into the atmosphere when high volume hydraulic fracturing is used, more than previously thought.
- Methane continues to leak into the atmosphere after the fracturing process is complete, during the drill-out phase.
- Methane is a “powerful” greenhouse gas, with a global warming potential greater than carbon dioxide.
- The greenhouse gas “footprint” of shale gas is 20% greater than conventional gas and oil.
- Therefore, shale gas will do more damage to the environment than conventional gas and oil, and even more damage than other fossil fuels like coal.
There have been many criticisms of the study, including a response from Energy in Depth (EID), a pro-drilling industry group. Among the problems with the study pointed out by EID:
- The study uses a standard, called the Global Warming Potential (GWP) factor, that is 45% higher than the GWP number used by the United Nations’ Intergovernmental Panel on Climate Change. That is, the study arbitrarily use a higher standard.
- The authors themselves admit, in the study, that the data is lousy. In some cases they have used obscure PowerPoint presentations found on the Internet as their evidence.
- The very numbers used for how much methane escapes into the atmosphere from hydraulic fracturing is not scientifically measured, but a guess based on assumptions.
- The authors also guess at how much gas leaks from pipelines and include that as part of the studies’ calculations (apples and oranges, the gas in pipelines does not necessarily come from shale gas).
- The authors have a political agenda as witnessed by their participation in anti-drilling meetings and rallies, and therefore their conclusions are colored (slanted?) by their politics.
The above bullet points are admittedly brief and attempt to summarize a complex issue. To dig deeper, read the study for yourself, and read the full point-by-point criticism from EID:
Climate Change (accessed Apr 12, 2011 via Mother Jones website) – Methane and the greenhouse-gas footprint of natural gas from shale formations
Energy in Depth (Apr 11, 2011) – Five Things to Know about the Cornell Shale Study