Emissions of key greenhouse far higher than thought: study

October 5, 2016 by Marlowe Hood
A methane extraction platform is seen in Rwanda

Global emissions of the potent greenhouse gas methane may be double current estimates, posing an added challenge in the fight against climate change, researchers said Wednesday.

The new study is based on a database 100 times larger than previous ones, and uses a methodology that avoid debatable assumptions underlying earlier models.

Within the figure, the methane leaked during the production and use of natural gas, oil and coal is 20 to 60 percent higher than previously thought, they reported in a study, published in the peer-reviewed journal Nature.

"Both emissions inventories and atmospheric studies have underestimated methane emissions from fossil fuel development," Stefan Schwietzke, a scientist at the US National Oceanic and Atmospheric Administration and lead author of the study, told AFP.

Emissions from industry and natural geological sources combined "are 60 to 110 percent greater than current estimates," he said.

The new findings may have serious implications for global efforts to cap global warming at "well under" two degree Celsius (3.6 degrees Fahrenheit), the target laid down in the landmark Paris Agreement that will enter into force next month, experts say.

"Emissions scenarios currently used for climate prediction need to be reassessed taking into account revised values for anthropogenic"—or human-generated—"methane emissions," said Grant Allen, a professor at the University of Manchester, commenting on the study.

Reaching the UN-backed temperature target, in other words, could be even more difficult than once thought.

While not as abundant or long-lived as carbon dioxide (CO2), methane (CH4) is 28 times more efficient at trapping heat in Earth's atmosphere over a 100-year time span.

It is the second largest contributor to global warming after CO2, accounting for about a fifth of accumulated temperature increase since the beginning of the industrial revolution in the mid-18th century.

Methane concentrations in the atmosphere more than doubled over the next 250 years before mysteriously peaking in 1999.

They remained constant until 2007. And then, after a brief hiatus, levels started to climb sharply again.

Most methane seeping into the atmosphere—up to twice as much as previous estimates, the study found—comes from human activity, whether from fossil fuel production or cattle, landfills and rice paddies

Experts disagree as to why, but whatever the cause fossil fuels are apparently not to blame, according to the study.

A ticking methane bomb

"Methane emissions from fossil fuel development have been dramatically underestimated," Schwietzke told AFP.

"But they're not responsible for the increase in total methane emissions observed since 2007."

Despite a dramatic jump in natural gas production during those years due to the controversial extraction method known as "fracking," related methane emissions remained constant because of reduced rates of leakage, he explained.

The silver lining of higher-than-expected from fossil fuels, he added, is a "great potential" for further improvements in the gas and oil industry.

Natural sources such as wetlands, wildfires, termites and wild animals account for a significant percentage of annual emissions.

But most methane seeping into the atmosphere—up to twice as much as previous estimates, the study found—comes from human activity, whether from fossil fuel production or cattle, landfills and rice paddies.

Changes in agriculture and reduction in meat consumption could also help reduce methane output, other studies have shown.

To get a better handle on the true quantity of methane seeping into the atmosphere, Schwietzke and his team assembled a database 100 times bigger that previous ones.

They also found a clever way to distinguish between different methane sources.

Otherwise identical methane molecules have slightly different carbon profiles, called isotopes, depending on whether they come from or from microbes at work, whether in wetlands or the digestive tracts of livestock.

Explore further: New research explores how wetlands and agriculture, not fossil fuels could be causing a global rise in methane

More information: Stefan Schwietzke et al. Upward revision of global fossil fuel methane emissions based on isotope database, Nature (2016). DOI: 10.1038/nature19797

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aksdad
1.6 / 5 (7) Oct 05, 2016
I wonder how our Gravettian predecessors during the Paleolithic fought against climate change 25,000 years ago as the world continued to get colder and more inhospitable before the peak of the last Ice Age? Or how our Renaissance ancestors fought climate change during the Little Ice Age? They probably just adapted and wished it was warmer like it was for those lucky devils during the Medieval Warm Period and like we have it now. But I guess some people aren't happy to have it so good. Maybe their ideal temperature is 1 or 2 C colder. They could always move to Canada...
Shootist
1.6 / 5 (7) Oct 05, 2016
ah the CO2 game has been lost now let's move onto the methane. leftists don't want the 99% eating cow and pig anyway, you boys have found yourselves another angle.

don't forget water vapor which is about the most potent GH gas.
gkam
2.1 / 5 (7) Oct 05, 2016
More sniping by the uneducated?

I suggest a rigorous course in Ecoscience, so you can learn all about our Life-Support System on Earth.
TheGhostofOtto1923
3 / 5 (4) Oct 06, 2016
More sniping by the uneducated?

I suggest a rigorous course in Ecoscience, so you can learn all about our Life-Support System on Earth.
I suggest a rigorous course of electroshock treatments for george kamburoff the lying cheating psychopath who never earned an undergrad degree.
Zzzzzzzz
4.2 / 5 (5) Oct 06, 2016
George's comment, while not a high value comment, so far is the ONLY comment on this article that has any value at all - psychopath or no
TheGhostofOtto1923
3 / 5 (2) Oct 07, 2016
George's comment, while not a high value comment, so far is the ONLY comment on this article that has any value at all - psychopath or no
I'm sorry what's valuable about implying that you need to take a course in ecoscience in order to understand what george kamburoff is saying?

You may not know that george repeatedly lies about having an MS in environmental mgt, among most everything else. We know he's a college dropout with no undergrad degree.

What is the value in defending such a liar, especially when he is denigrating someone else for being uneducated?

WTF is the matter with you? Oh I know

"My biggest frustration and source of anger, is at those who have refused to take a stand when they see the abuse . No matter how outrageous his behavior others often stood by and inadvertently fuelled his grandiosity and denial... although denial is too mild a word for it."

-You're a dupe.
geokstr
2.3 / 5 (4) Oct 07, 2016
"...debatable assumptions underlying earlier models.

What? Wait a minute!

We've been hearing for decades that the "models" are wonderful. Now that the population is losing interest in the apocalyptic predictions of the Warmists and Marxists, suddenly they find that their assumptions about a more dangerous gas than animal exhalations were all wrong - here's new and better assumptions to "prove" it's 10X the apocalypse now.

This is blatant in-your-face blarney that Obama and Hillary spin all the time - lie, cover-up, twist, deflect and pound the table - enough of the sheep will pull the "D" lever out of habit no matter what they do. They've been trained for generations in propaganda mills we used to call schools and universities that D = utopia and R = evil, racist, mysogynist, Islamo/homo/transphobic capitalist-roader.

Pavlov was right all along, and Alinsky is proving it.

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