"Fracking" Shale Gas Emissions Far Worse Than Coal For Climate - Cornell Study

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**UPDATE: The Cornell paper is now available in final, published format here: “Methane and the greenhouse-gas emissions footprint of natural gas from shale formations.”[PDF]

The Hill reported this morning on a groundbreaking report from Cornell University researchers confirming that shale gas recovered through high volume hydraulic fracturing, or “fracking,” will produce even more greenhouse gases than the burning of coal in the next two decades - a critical window in which society must reduce emissions to combat climate change. While natural gas is often viewed as a “cleaner alternative” to conventional fossil fuels - and is often promoted as a “bridge fuel” by environmentalists and politicians alike - the new Cornell report explodes this myth.

Gas is not just a “bridge to nowhere,” it turns out to be a highway to hell. The Cornell study makes clear that the widely-held perception that gas is the “cleaner” darling of the fossil fuel trio is a myth. With total methane emissions factored in, shale gas turns out to have the greatest climate impact of all the fossil fuels.

Contrary to popular belief, gas is just as polluting as coal in the long term - and far worse in the near term due to the higher warming impact from methane when it is first released to the atmosphere during the controversial fracking stage.  This news is certain to rattle policymakers in Washington who have promoted gas as a solution to our energy crisis. The Cornell paper is a game changer, and its release this week should command the attention of everyone concerned about our energy future.

The peer-reviewed paper, authored by Cornell experts Robert Howarth, Anthony Ingraffea and Renee Santoro, is expected to be published later this week in the journal Climatic Change.

From the leaked draft of the study:

“The greenhouse gas footprint for shale gas is greater than that for conventional gas or oil when viewed on any time horizon, but particularly so over 20 years. Compared to coal, the footprint of shale gas is at least 20% greater and perhaps more than twice as great on the 20-year horizon and is comparable when compared over 100 years… These methane emissions are at least 30% more than and perhaps more than twice as great as those from conventional gas. The higher emissions from shale gas occur at the time wells are hydraulically fractured – as methane escapes from flow-back return fluids – and during drill out following the fracturing.”

Fracking, sadly, has been given the green light for now by the Obama administration, and the president himself recently touted the fact that, thanks to this procedure, the U.S. now has access to huge reserves of fuel for the future. The Energy Information Administration currently estimates that the U.S. will rely on shale gas for roughly 45% of our energy needs by the year 2035.

DeSmogBlog has noted extensively in the past some of the dangers associated with fracking, including the threat of toxic chemicals and radiation from the process leaking into drinking water supplies and local waterways. The New York Times “Drilling Down” series by Ian Urbina revealed several new angles about the threats posed by fracking for shale gas, and new information about the risks of gas drilling are emerging on a near-daily basis.

The full Cornell paper will be published in the journal Climatic Change later this week. Stay tuned for further analysis of this groundbreaking study, and more information about the perils of relying on dirty gas for our energy needs.

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Anyone who thinks the paper by Howarth et al is a “game changer” has not read the paper. As science goes, this paper is exceptionally weak. Worst of all, in concluding that natural gas from shale is “worse” than coal in GHG release, it assumes there is no methane released into the atmosphere by coal mining. What do you think the exhaust fans are releasing to keep the mines from exploding during mining? Inadvertant release of methane during shale gas drilling is worth examining, but this paper is simply not a credible effort to do so.

Sorry, “green hornet” but your claim is simply false. They definitely do include an estimate for methane emissions from coal mining. You would know this if you had looked at their Figure 1.A. See the caption? See the top bar in the stacked bar for coal mining? There it is, methane emissions from coal mining. Not hard to see.

“Simply not credible”? Who should I listen to: an anonymous blog poster who ignores Figure 1 in the paper, and
gives zero sources for a better analysis, just a dismissive toss-away? Or should I listen to this paper, which goes into detailed accounts of each stage in each type of production, cites numerous studies by well known authors on carbon emissions, states the uncertainty ranges for each figure and stays with conservative estimates, and shows their calculations for the overall comparisons?

Im afraid youve fallen into the fallacy of argument from incredulity: *you* failed to be persuaded by the paper, so you want to claim that this makes the paper “simply not credible” to everyone. Sorry, doesnt follow.

Maybe a better study will come along later that improves on this work or even corrects some fault, but that will take work, research and specifics with hard numbers - not just your hasty smackdown with one single critical claim, that one criticism veing itself easily shown to be incorrect.

And the reference source for the data on coal mine release of methane is where? The paper states the data were determined/derived from “Supplemental Electronic Materials”. Yet the discussion of published references cited in the paper states: “However, we can compare our estimates for conventional gas with three previous peer-reviewed studies on the GHG emissions of conventional natural gas and coal: Hayhoe et al. (2002), Lelieveld et al. (2005), and Jamarillo et al. (2007). All concluded that GHG emissions for conventional gas are less than for coal, when considering the contribution of methane over 100 years.”

So the evidence for the thesis proposed in this paper resides in a Figure in which the data on coal mines from which the Figure was derived are not available to the reader. Are you aware of studies on the amount of methane released by venting of coal mines over the life of the mine? If these papers exist, why were they not cited?

Green hornet, you seem to be straining to find fault with this study. You list the sources they cite for the point you question, then ask why they dont cite sources… Huh? Are you saying the cited works arent “available”?

I readily found Hayhoe 2002 via Google Scholar:


And it provided this link to the full text PDF:

Please read that and let me know if you think it addresses your issue about evidence or whatever.

Here is a source that collects several recent estimates of methane emissions from a wide range of sources including coal mining:
What I take from these figures is that human driven CH4 emissions are around 1.5 to 2x natural emissions, and that CH4 from coal mining comes in around 5 to 10 percent of the human contribution.
What exactly is “not available”?

Jim - no, I wasn’t referring to the citations you mentioned as “not available”. Sorry I confused the issue by inserting that excerpt from the paper in my reply at the place I did. In the Results section of the paper, where the authors describe Figure 1, they note that the derivation of the data used to construct the bar graphs for diesel and coal came from “Electronic Supplemental Materials”. It is not clear what these materials are, but they are not (or at least don’t appear to be) the 3 papers mentioned in the Discussion. I haven’t been able to find papers that have measured the amounts of methane exhausted by coal mine vents. I’ll check the sources you provided in your later post. In order to make the assertion that shale gas is worse that coal for GHG emissions, it seems to me the onus is on the authors to inform the reader how they reached the conclusion that methane release from coal mines is negligible (which is what Fig 1 says). If they were truly negligible, why would the mine need to run the venting fans 24/7 to prevent explosive levels of CH4 buildup in the shafts?

I did read Joe Romm’s blog today regarding his phone call to the author. I thought it was interesting that the author told Joe that the findings were based on very limited data and needed further verification before conclusions were reached. However, the media and members of Congress will leap on the headline of “nat gas worse than coal”. This I think is regretable because that conclusion is far from settled. What we can probably agree on is that there is leakage of methane from the drilling of shale gas wells, and this deserves further study, as well as mitigation. However, the second part of the paper’s assertion that shale gas is worse than coal seems scientifically weak and at this point, at least from the data presented, unfounded.

Kind of a tough sale. According to the NOAA, the rate at which atmospheric methane increase has declined since the 80s and is currently negative.

This comment is a bit hard to follow, but seems to be trying to say that total methane concentration in the atmosphere has either stopped rising? Or the rate of increase has slowed? Whichever you meant, methane emssions have not stopped, and concentrations are certainly not falling.
In any case thats not really a good objection to the point of this paper. Frakking is a new practice and is just starting to be widely used. We could expect more methane increases in the future based on the figures in this paper for emissions during frakking and drilling out, if indeed frakking grows at the kind of rate they project. But current and recent methane trends are dominated by other factors than frakking up to this point, so you cannot use that to argue that frakking is not in fact causing the level of fugitive emissions asserted in this paper.

Try: http://en.m.wikipedia.org/wiki/Atmospheric_methane.

Read under the heading “Emissions accounting of methane”.

You can complain that this is a Wiki reference if you want, but there are ample citations within the article and you are free to read to your hearts content.

Rob is correct that NOAA has shown a drop in atmospheric methane over the past decade, although it has begun to rise again in the latter years of the decade. A NOAA spokesperson suspects most of that rise may be due to warming of the arctic and release of large amounts of methane as permafrost melts.

To quote: “Rapidly growing industrialization in Asia and rising wetland emissions in the Arctic and tropics are the most likely causes of the recent methane increase, said scientist Ed Dlugokencky from NOAA’s Earth System Research Laboratory. “We’re on the lookout for the first sign of a methane release from thawing Arctic permafrost,” said Dlugokencky. “It’s too soon to tell whether last year’s spike in emissions includes the start of such a trend.”

While I don’t doubt there is some release of methane during the process of drilling shale for natural gas, this has to be put in the context of other sources of methane release into the atmosphere. In their obvious desire to poo-poo natural gas derived from fracturing shale, the authors of this paper have handed the proponents of coal-fired electricity a nice piece of propaganda.

I dont see it that way, GH. Poeple used to claim that n gas was less carbon intensive than coal per unit of delivered energy. That would be true if gas drilling had low “fugitive” losses. Thus study raises the concern that frcking may be driving up such leaking, enough to put the leakier cases of conventional gas drilling and almost all fracking wells above coal mining for overall carbon intensity.
That doesnt make coal any cleaner, and i think the oublic should get that.
A longer discussion of this article is ongoing over at Joe Romms climateprogress.org
Joe aptly sums up the significance of this work. He interviewed Horwath for his write up. Well worth a read.

“Groundbreaking”? Hardly. It is a report, not a study, and presents conclusions the authors want it to present. It reads like a first draft, the language usage is so clunky in it.

Now that is just silly, paul_s. I read the paper and it reads just fine; i did not find the language “clumky” - ratzher it seemed to me well written, clearly worded and fully documented with figures and citations.

You will have to do better than just name calling. I invite interested readers to see for themselves how the paper “reads” and whether or not it seems “clumky.”

Paul_s may well want to change the subject by pointing out my double typos in tryint to spell the word “clunky” above. Perils of virtual iPad keyboard…

We need to do something and save our planet, we need 1 million person like you and this will be a better place to live. thanks for your info.