Howarth: A Credibility Gap

Research on methane emissions from natural gas discredited by scientific community

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Cornell's Robert Howarth and Tony Ingraffea, the authors of "Methane and Greenhouse-Gas Footprint of Natural Gas from Shale Formations," make inaccurate and extreme choices far outside established science at virtually every turn. The result is a report that misleads the public about important facts involving natural gas production. Howarth has since issued a follow-up report to try and justify his findings and defend himself against critics, which include colleagues from his own university within the earth and atmospheric sciences and chemical and biological engineering departments. In his latest round of activist research, Howarth continues to press his beliefs despite the continued absence of any new data or viable information. Bottom line: Regurgitating inaccurate work does not make it legitimate.

Inaccurate on Plant Efficiency

Howarth placed the efficiency of a coal plant at up to 47 percent, while saying a gas plant tops out at about 53 percent. John Reilly, a lecturer at MIT's Sloan School of Management and some of his MIT colleagues wrote in the Huffington Post that "natural gas base-load units have efficiencies in the 40-54 percent range, compared to 30-35 percent for the current fleet of coal plants." Howarth did not include this difference, or any efficiency difference, in his assessment.

Lack of Expertise

As an evolutionary biologist, Howarth is not credentialed to do the kind of chemical analysis required for this field of study. In fact, he was forced to retract the previous abstract for this paper because he didn't know that methane is also emitted during coal production ("I blew it" was his quote).

Weak Data

Howarth admitted that the weakest part of his report was "absolutely" the data on shale plays.

He even called some of his data sources "weird." Howarth uses a very limited set of data, repeatedly noting data that is "not well documented;" data where "more work is needed;" and estimates that were "uncertain." Yet he shows no uncertainty about his extreme conclusions.

False Claims

Howarth also made claims that most of the methane from coal mines is captured, prompting EPA's Roger Fernandez, Team Leader for Oil and Gas Climate Change Programs, to call foul.  "I have to respectfully disagree on that," Fernandez said of Howarth's assertion. "There is a huge amount of methane that is vented through ventilation systems."

Academics from Howarth's own Cornell University as well as Carnegie Mellon, the Energy Department's National Energy Technology Laboratory, the environmental group WorldWatch Institute, MIT and IHS CERA are among groups that have taken issue with Howarth. Based on his admissions on the weakness of his data, and his clear misstatements about the science, Howarth should earn more skeptics as he continues to mislead important public dialogues about our nation's energy choices.

Scientists Speak Out

A wide array of highly credentialed scientists and experts are stepping forward to challenge Howarth's reckless claims and explain the faulty methodology that produced his inaccurate conclusion. Even Howarth's own university has raised serious concerns about his methodology.

Cornell University

Lawrence M. Cathles, III, Larry Brown, Milton Taamb, Andrew Hunter

"Howarth et al. assume implausibly high leakage rates and fail to provide any clear evidence of methane leakage from shale gas wells during completion, or from all gas wells during handling, transmission, storage, and delivery of the gas, that would significantly increase the greenhouse impact of simply burning the methane.  Moreover, they dismiss the impact of existing technology for reducing whatever emissions are now problematic.

For high volume shale gas wells the leakage rates they assert as routine would indicate about a million dollars of methane is vented to the atmosphere from each high volume well.  Not only is this an economic loss no business would contemplate, it represents a risk no company (or their insurer or regulator or rig workers) would accept."

IHS CERA

If methane emissions were as high as EpA and Howarth assume, extremely hazardous

"If methane emissions were as high as EPA and Howarth assume, extremely hazardous conditions would be created at the well site.  Such conditions would not be permitted by industry or regulators.  For this reason, if no other, the estimates are not credible."

conditions would be created at the well site. Such conditions would not be permitted by
industry or regulators. For this reason, if no other, the estimates are not credible.

Carnegie Mellon University

A recent Carnegie Mellon University study finds that natural gas from the Marcellus shale has "generally lower" life cycle GHG emissions than other power sources for producing electricity.

Andrew C. Revkin

The New York Times

"The data clearly shows that substituting natural gas for coal will have a substantial greenhouse benefit under almost any set of reasonable assumptions."

Michael Levi

Senior Fellow for Energy and Environment and Director of the Program on Energy Security and Climate Change, Council on Foreign Relations

"His analysis is based on extremely weak data, and also has a severe methodological flaw (plus some other questionable decisions), all of which means that his bottom line conclusions shouldn't carry weight."

"Howarth's gas-to-coal comparisons are all done on a per energy unit basis. That means that he compares the amount of emissions involved in producing a gigajoule of coal with the amount involved in producing a gigajoule of gas. (Don't worry if you don't know what a gigajoule is - it doesn't really matter.) Here's the thing: modern gas power generation technology is a lot more efficient than modern coal generation, so a gigajoule of gas produces a lot more electricity than a gigajoule of coal. The per kWh comparison is the correct one, but Howarth doesn't do it. This is an unforgivable methodological flaw; correcting for it strongly tilts Howarth's calculations back toward gas, even if you accept everything else he says."

Melanie Kenderdine

Executive Director, MIT Energy Initiative

"What he has done in his analysis is deviated from what are accepted standards, accepted by EPA, DOE, the IPCC, European Trading Scheme, California Air Resources Board, where essentially the denominator that they use to calculate the impacts of various greenhouse gases is an agreed upon hundred years; Professor Howarth uses 20 years."

"They [the scientists at MIT] have looked at the numbers. They've looked at EPA's new numbers on methane emissions and concluded that emissions from natural gas and power generation, for example, are very, very robust compared to coal. They're about half of what you - when you combust natural gas compared to combusting coal for power generation, natural gas emits about half of the emissions of coal and they think that it has a relatively small impact."

John Hanger

Former Secretary, Pennsylvania Department of Environmental Protection

"The author of any life cycle analysis can get to a result quite easily, because life cycle analysis swings greatly on the assumptions, data inclusions, and data exclusions. It is not a simple scientific measurement."

"And Professor Howarth does want the result to which he gets. He is a committed opponent of gas drilling and fracking, a position to which he is entitled in this free country."

"What else has Professor Howarth said about the data that he uses in his study? On March 15, 2011 he is quoted as calling the data used in his study as 'lousy,' 'really low quality,' 'teased apart out of PowerPoint presentations here and there.' In a court of law, those would be case determining admissions. In a boxing match, the ref would stop the match. In science, they are an expressway to junk."

"Especially troubling to me, Professor Howarth also rejects major conclusions from the Intergovernmental Panel on Climate Change that would lead to a big Bronx cheer were polluters to do the same in service of their life cycle analysis."

"Professor Howarth's conclusion that gas emits more heat trapping gas than carbon flies in the face of numerous life cycle studies done around the world. And more studies from credible organizations with strong environmental credentials are in the works."

Roger Fernandez, Team Leader for O&G Climate Change Programs, EPA

"We are going to update the inventory and I think you'll see some of those numbers come down, because we are going to do some further analysis in regard to what the entire industry is doing rather than just that being reported to us."

Geoffrey Styles

Managing Director, GSW Strategy Group

"Practically every paragraph includes an assumption, simplification or choice by the authors that tends to increase the calculated environmental impact of natural gas. Whether that's the result of bias or merely a series of judgment calls, it undermines confidence in the final conclusions at the same time it amplifies them."

"Probably the most significant choice the authors made was to emphasize the global warming impact of methane (the main component of natural gas) over a 20-year period, in preference to than the more commonly used 100-year interval. Then they bypassed the established Global Warming Potential (GWP) factors from the UN IPCCC's Fourth Assessment Report to use much higher factors for methane from a 2009 paper published in Science."

"The other major choice the authors made was to ignore the downstream conversion of gas and coal into electricity. As lifecycle analysis, this earns a failing grade."

Dave McCabe

Atmospheric Scientist, Clean Air Task Force

This paper is selective in its use of some very questionable data and too readily ignores or dismisses available data that would change its conclusions," says Dave McCabe, an atmospheric scientist for the Clean Air Task Force.

  • Source: Clean Air Task Force Blog