Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Surge in methane emissions threatens efforts to slow climate change

12.12.2016

Global methane budget released

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.


Methane emissions by source are illustrated.

Credit: Global Carbon Project of Future Earth

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.

Scientists involved in the editorial will discuss these trends at a session during the fall meeting of the American Geophysical Union (AGU) in San Francisco on Tuesday, 13 December.

The findings could give new global attention to methane - which is much less prevalent in the atmosphere than carbon dioxide but is a more potent greenhouse gas, trapping 28 times more heat. And while research shows that the growth of carbon dioxide emissions has flattened out in recent years, methane emissions seem to be soaring.

"The leveling off we've seen in the last three years for carbon dioxide emissions is strikingly different from the recent rapid increase in methane," says Robert Jackson, a co-author of the paper and a Professor in Earth System Science at Stanford University. The results for methane "are worrisome but provide an immediate opportunity for mitigation that complements efforts for carbon dioxide."

The authors of the new editorial previously helped to produce the 2016 Global Methane Budget. This report provided a comprehensive look at how methane had flowed in and out of the atmosphere from 2000 to 2012 because of human activities and other sources. It found, for example, that human emissions of the gas seemed to have increased after 2007, although it's not clear by how much. The methane budget is published every two to three years by the Global Carbon Project, a research project of Future Earth.

Methane, Jackson says, is a difficult gas to track. In part, that's because it can come from many different sources. Those include natural sources like marshes and other wetlands. But the bulk, or about 60 percent, of methane added to the atmosphere every year comes from human activities. They include farming sources like cattle operations - cows expel large quantities of methane from their specialised digestive tracks - and rice paddies - the flooded soils make good homes for microbes that produce the gas. A smaller portion of the human budget, about a third, comes from fossil fuel exploration, where methane can leak from oil and gas wells during drilling.

"Unlike carbon dioxide, where we have well described power plants, almost everything in the global methane budget is diffuse," Jackson says. "From cows to wetlands to rice paddies, the methane cycle is harder."

But a range of information - such as from large-scale inventories of methane emissions, measurements of methane in the air and computer models - suggests that this cycle has shifted a lot in the last two decades. Jackson and his colleagues, for instance, report that the growth of methane in the atmosphere was mostly stagnant in 2000 to 2006. But that changed after 2007.

"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."

Saunois adds that this runaway pace could threaten international efforts to limit warming from climate change to 2 degrees Celsius. The research provides a strong argument that "we should do more about methane emissions," Saunois says. "If we want to stay below 2 degrees temperature increase, we should not follow this track and need to make a rapid turn-around."

Pinpointing where those methane emissions are coming from, however, isn't easy. Many environmental advocates in North America have raised concerns that expanded drilling for natural gas in recent years could lead to a surge in methane emissions. But Saunois says that based on available data, the more likely source, at least for now, is agriculture. She and her colleagues aren't sure what may be driving this increase. According to the Food and Agriculture Organization of the United Nations, livestock operations around the world expanded from producing 1,300 million head of cattle in 1994 to nearly 1,500 million in 2014 - with a similar increase in rice cultivation in many Asian countries.

Saunois and Jackson argue, however, that the story isn't all bad news. A number of researchers have experimented with different ways of reducing methane emissions from farms. Feeding cows a diet supplemented with linseed oil, for example, seems to reduce the amount of methane they belch out. "When it comes to methane, there has been a lot of focus on the fossil fuel industry, but we need to look just as hard if not harder at agriculture," Jackson says. "The situation certainly isn't hopeless. It's a real opportunity."

###

About the study:

The article "The growing role of methane in Anthropogenic Climate Change" will be published in Environmental Research Letters on 12 December at http://iopscience.iop.org/article/10.1088/1748-9326/11/12/120207
Authors: Saunois, M., Jackson, R.B., Bousquet, P., Poulter, B., Canadell, J.G.

Contact information:

Media inquiries:

Communications:

Owen Gaffney
Future Earth, media (Stockholm)
Tel: +46 (0) 734604833
Owen.gaffney@su.se

Daniel Strain
Future Earth, media (Colorado)
daniel.strain@futureearth.org

Scientific authors

Marielle Saunois, Université de Versailles Saint Quentin/Laboratoire des Sciences du Climat et de l'Environnement; email: marielle.saunois@lsce.ipsl.fr

Rob Jackson, Stanford University; email: rob.jackson@stanford.edu

Philippe Bousquet, Laboratoire des Sciences du Climat et de l'Environnement; email: Philippe.Bousquet@lsce.ipsl.fr

Josep Canadell, Global Carbon Project/CSIRO Oceans and Atmosphere; email: pep.canadell@csiro.au

Future Earth

For more information about the Global Carbon Project, visit: globalcarbonproject.org
For more information about Future Earth, visit: futureearth.org

Owen Gaffney | EurekAlert!

More articles from Earth Sciences:

nachricht Global study of world's beaches shows threat to protected areas
19.07.2018 | NASA/Goddard Space Flight Center

nachricht NSF-supported researchers to present new results on hurricanes and other extreme events
19.07.2018 | National Science Foundation

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Future electronic components to be printed like newspapers

A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.

The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

A smart safe rechargeable zinc ion battery based on sol-gel transition electrolytes

20.07.2018 | Power and Electrical Engineering

Reversing cause and effect is no trouble for quantum computers

20.07.2018 | Information Technology

Princeton-UPenn research team finds physics treasure hidden in a wallpaper pattern

20.07.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>