Wednesday, December 14, 2016

Fake News Blaming Cattle for Methane Rise



This week, the headlines have been telling us that a new scientific report suggests that an unexplained hike in global methane levels is likely caused by agriculture, specifically rice paddies and cattle.

The source that I used in my news thread yesterday was from EurekAlert:
Global concentrations of methane, a powerful greenhouse gas and cause of climate change, are now growing faster in the atmosphere than at any other time in the past two decades.

That is the message of a team of international scientists in an editorial to be published 12 December in the journal Environmental Research Letters. The group reports that methane concentrations in the air began to surge around 2007 and grew precipitously in 2014 and 2015. In that two-year period, concentrations shot up by 10 or more parts per billion annually. It's a stark contrast from the early 2000s when methane concentrations crept up by just 0.5 parts per billion on average each year. The reason for the spike is unclear but may come from emissions from agricultural sources and mainly around the tropics - potentially from farm sites like rice paddies and cattle pastures.

So, the problem the scientists are reporting is that there was a two year time period when methane emissions shot up by 10 or more parts per billion annually, beginning to surge in 2007 at a rate which continued upwards through 2014 and 2015.

The reported conclusion (if you can call it a conclusion)?

Cattle and rice farming, perhaps in the tropics "may be" the reason.

Although... from the same study...
"Why this change happened is still not well understood," says Marielle Saunois, lead author of the new paper and an assistant professor of Université de Versailles Saint Quentin and researcher at Laboratoire des Sciences du Climat et de l'Environnement in France. "For the last two years especially, the growth rate has been faster than for the years before. It's really intriguing."

The Guardian reports...
The scientists speculate that agriculture may be the main source of the additional methane that has been recorded. However, they cannot be sure of all the sources, owing to a lack of monitoring.
So we've got a story, folks, which is being echoed across main stream media sources and social media, reported from a trusted scientific study that says methane began a rapid rate of increase in 2007. How much did the cattle population go up in 2007, then, is the question, if it was "likely because of cattle"? How much did the ruminant population expand in 2007? 2008? Unless we stopped butchering a large percent of ruminants in 2007, then we cannot have a sudden rapid increase in ruminant numbers given they only produce 1 calf per year, or infrequently, two.

There's one thing that did change rapidly beginning in 2007, and that was the advent of fracking. I don't want to jump to any conclusions, because I didn't do the research. I'm just stating the obvious. But the study did not think that this spike in methane is caused by the oil and gas industry. Another obvious situation is that we don't know how much Arctic methane is being released from warmer temperatures, as we've been warned so many times could be a tipping point situation.

Yet, the scientists and all of the media conclude, that the study's rapid methane increase is probably caused by cattle and rice paddies, and then they put up a picture of cattle to go with the story.

Let's take a look at a Google search I did on this story. Look at the images.



Here's the AP story which hit newspapers everywhere:


Here's from the FERN Ag news report:


Finally, how did the study measure methane? Did any of the measurement techniques or locations change in 2007? I am not discounting methane emissions from rice paddies and cattle, but I question whether they have caused the rapid spike reported by this study, and I question why it gets reported by news sources which consider themselves credible.

I wouldn't have made this post if it hadn't been for Twitter. Two people tweeted the "assumption" to me. Here is some of the exchange, beginning with a tweet I made 24 hours ago.


People talk past each other on Twitter, but I finally got a reaction later from the other side of the world:











Here are my questions and I invite anyone who thinks this study showed that cattle are responsible for the sudden spike in methane beginning in 2007 to leave a comment.

1. How much did the global ruminant population rise in 2007? 2008? 2009? as compared to 2006? 2005? 2004?

2. How much methane was released from Arctic thawing in 2007? 2008? as compared to 2006? 2005?

3. How much methane was released from our fossil fuel "bridge fuel" natural gas fracking in 2007? 2008? as compared to 2006? 2005?

4. How was methane measured for this study in 2007? 2008? 2014? 2006? 2005? 2002?

Looking for those numbers should get us started.

Conclusion
We have reached a sad day in science and news reporting when a conclusion that is "unclear" gets reported across the board as "maybe" being caused by something specific. The word bias comes to mind. Please prove me wrong, someone. I invite you to.



ALSO RECOMMENDED:

1. Modern Day Cattle Haven't Increased Greenhouse Emissions Over Ruminant Emissions 500 Years Ago

2. What About this War on Meat?

3. The Myth that Cattle are a Climate Change Catastrophe



UPDATE:
Note that Inside Climate News also presented credible challenges to this study. See my comment below with the quote.

6 comments:

  1. when this question came up earlier, i quoted from memory that US cattle population had decreased from about 125 million to 100 million...i just found a graph showing that it has fallen from 130 million to 90 million:

    http://www.foodsafetynews.com/2013/12/beef-industry-money-affected-by-record-low-cattle-population/

    so i looked for global stats...a graph sourced from the FAO shows cattle, buffalo and goat populations rising, sheep falling up to 2010: http://www.earth-policy.org/data_highlights/2011/highlights14

    but a more recent graph shows global cattle population falling in 2015 and 2016: https://www.statista.com/statistics/263979/global-cattle-population-since-1990/

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  2. Can't remember where I read this but it seems that there is a fairly significant amount of methane released by fires, both grass and forest.
    Given the increase in really big forest fires, the most recent and still not controlled being in Tennessee and Georgia, as well as the one in Canada that went on for months last year, one has to wonder how much that release of methane might affect the rise in methane levels.

    There are continuing forest fires, brush fires, grass fires and peat fires (which seem to release the most methane and last the longest) all over the world. This has to impact the methane increase figures.

    Luane Todd

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  3. While its clearly over-reach to blame this surge in methane on cattle based on the presented evidence, it seems that the biggest problem is the impression given by the images used in all these stories. Most of the stories I glanced through made reasonably cautious statements about the "possible" role of cattle. Even most of the headlines used were reasonable.

    I think labelling them as "fake news" is a bit over the top when that term has recently been associated with outright lies and nonsense like "FBI Agent Suspected in Hillary Email Leaks Found Dead in Apparent Murder-Suicide".

    The issue of methane (and nitrous oxide) emissions in ag is genuine and will become more and more contentious as renewable energy begins to make significant inroads into the CO₂ component of the climate challenge. Even if it turns out cattle are not responsible for the increase, if the methane surge continues it is likely to put pressure for scrutiny on all sources of methane.

    I think ag industries need to be more proactive and be wary of relying on the old "no proof" line. The risk is that it starts to sound like the tobacco industry in the 70's and we know how that ended up.

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    1. I am hopeful that the key lies in restoring soil health back to its non sterile state. It would appear that that would or might involve ruminants and other creatures so that the circle of life can work together in its complex ways that we are only beginning to understand. Land use change, the kind of agriculture we devote our land to as a result of policy, think corn ethanol fuel for example, the way in which we raise our livestock, all of those things matter.

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  4. This is very interesting. Inside Climate News also presents a challenge to this study (though they used a cow photo, too):

    Here's what they said, "Researchers trying to identify the sources of methane look at its carbon fingerprint—its isotopic signature. That signature looks different when the methane comes from a burning forest, for example, than from a cow's burp. But when researchers look at multiple sources of methane, and multiple carbon-13 signatures, it can become less clear where the methane is coming from, which the study's authors acknowledge.

    "We have good, but certainly not great power for attributing methane sources," Jackson said. "We have information from isotopes. We get some information from latitudinal differences"—all consistent with agricultural sources, he said.

    Robert Howarth, a professor of ecology and environmental biology at Cornell University, challenged the findings. He said the signature of shale gas—the source of the natural gas and fracking boom—can vary widely. Howarth also noted that some satellite data says the global methane increases have come from the U.S., where cattle population has dropped and rice production has mostly leveled off.

    "They're assuming the [carbon-13] in all natural gas is constant, and that might have been true 10 years ago. But in the U.S. there's been a huge increase in shale gas, and the signature for shale gas can look a lot like the signature from a cow," Howarth explained. He concludes it's likely that more methane is actually coming from the energy sector."

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  5. i've never put any stock in blaming a sudden spike in methane on agriculture, which hasn't changed that much over millenniums...the continual drumbeat to blame it on ruminants leads me to suspect that story is being pushed by vested interests and justified with half-baked science...there's an entire industry with a lot of money riding on putting the blame for the methane increase on something other than fossil fuels...

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