This looks like a fairly thorough riposte to the Cornell shale gas study. I don't think "debunking" is too strong a word for it. The article lists five things you need to know about the Cornell study. Here's a sample:
Thing #1: The study’s conclusions rely almost entirely on the application of a Global Warming Potential (GWP) factor that’s 45 percent higher for natural gas than the one cited by the UN’s Intergovernmental Panel on Climate Change (IPCC) in 2007.
Thing #2: Even the study’s authors admit their data is “lousy.”...
Thing #4: The authors’ estimates on pipeline leakage are based on data and assumptions that are completely irrelevant to the Marcellus Shale...
I always had it in my mind that Cornell was a good university. But it's going to be hard to maintain that idea in the face of stuff like this.