Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Arctic seafloor methane releases double previous estimates

26.11.2013
The seafloor off the coast of Northern Siberia is releasing more than twice the amount of methane as previously estimated, according to new research results published in the Nov. 24 edition of the journal Nature Geoscience.

The East Siberian Arctic Shelf is venting at least 17 teragrams of the methane into the atmosphere each year. A teragram is equal to 1 million tons.


Photo courtesy of Natalia Shakhova
Methane burns as it escapes through a hole in the ice in a lagoon above the East Siberian Arctic Shelf.

“It is now on par with the methane being released from the arctic tundra, which is considered to be one of the major sources of methane in the Northern Hemisphere,” said Natalia Shakhova, one of the paper’s lead authors and a scientist at the University of Alaska Fairbanks. “Increased methane releases in this area are a possible new climate-change-driven factor that will strengthen over time.”

Methane is a greenhouse gas more than 30 times more potent than carbon dioxide. On land, methane is released when previously frozen organic material decomposes. In the seabed, methane can be stored as a pre-formed gas or asmethane hydrates. As long as the subsea permafrost remains frozen, it forms a cap, effectively trapping the methane beneath. However, as the permafrost thaws, it develops holes, which allow the methane to escape. These releases can be larger and more abrupt than those that result from decomposition.

The findings are the latest in an ongoing international research project led by Shakhova and Igor Semiletov, both researchers at the UAF International Arctic Research Center. Their twice-yearly arctic expeditions have revealed that the subsea permafrost in the area has thawed much more extensively than previously thought, in part due to warming water near the bottom of the ocean. The warming has created conditions that allow the subsea methane to escape in much greater amounts than their earlier models estimated. Frequent storms in the area hasten its release into the atmosphere, much in the same way stirring a soda releases the carbonation more quickly.

“Results of this study represent a big step forward toward improving our understanding of methane emissions from the East Siberian Arctic Shelf,” said Shakhova. She noted that while the ESAS is unusual in its expansive and shallow nature, the team’s findings there speak to the need for further exploration of the subsea Arctic. “I believe that all other arctic shelf areas are significantly underestimated and should be paid very careful attention to.”

The East Siberian Arctic Shelf is a methane-rich area that encompasses more than 2 million square kilometers of seafloor in the Arctic Ocean. It is more than three times as large as the nearby Siberian wetlands, which have been considered the primary Northern Hemisphere source of atmospheric methane. Previous estimates performed for the ESAS suggested that the area was releasing 8 teragrams of methane into the atmosphere yearly.

During field expeditions, the research team used a variety of techniques—including sonar and visual images of methane bubbles in the water, air and water sampling, seafloor drilling and temperature readings—to determine the conditions of the water and permafrost, as well as the amount of methane being released.

Methane is an important factor in global climate change, because it so effectively traps heat. As conditions warm, global research has indicated that more methane is released, which then stands to further warm the planet. Scientists call this phenomenon a positive feedback loop.

“We believe that the release of methane from the Arctic, and in particular this part of the Arctic, could impact the entire globe,” Shakhova said. “We are trying to understand the actual contribution of the ESAS to the global methane budget and how that will change over time.”

Shakhova and Semiletov are also affiliated with the Pacific Oceanological Institute at the Russian Academy of Sciences, Far Eastern Branch, as are research team members Anatoly Salyuk, Denis Kosmach and Denis Chernykh. Other members of the research team include Dmitry Nicolsky of the UAF Geophysical Institute; co-lead author Ira Leifer of the Marine Sciences Institute at the University of California, Santa Barbara and Bubbleology Research International; Valentin Sergienko of the Institute of Chemistry at the Russian Academy of Sciences, Far Eastern Branch; Chris Stubbs of the Marine Sciences Institute at the University of California, Santa Barbara; Vladimir Tumskoy of Moscow State University; and Örjan Gustafsson of the Department of Applied Environmental Science and Bolin Centre for Climate Research, Stockholm University.

Marmian Grimes | EurekAlert!
Further information:
http://uafcornerstone.net/ESAS2013/
http://www.alaska.edu

More articles from Earth Sciences:

nachricht New plate adds plot twist to ancient tectonic tale
15.08.2017 | Rice University

nachricht Global warming will leave different fingerprints on global subtropical anticyclones
14.08.2017 | Institute of Atmospheric Physics, Chinese Academy of Sciences

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

Im Focus: Scientists improve forecast of increasing hazard on Ecuadorian volcano

Researchers from the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science, the Italian Space Agency (ASI), and the Instituto Geofisico--Escuela Politecnica Nacional (IGEPN) of Ecuador, showed an increasing volcanic danger on Cotopaxi in Ecuador using a powerful technique known as Interferometric Synthetic Aperture Radar (InSAR).

The Andes region in which Cotopaxi volcano is located is known to contain some of the world's most serious volcanic hazard. A mid- to large-size eruption has...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

New thruster design increases efficiency for future spaceflight

16.08.2017 | Physics and Astronomy

Transporting spin: A graphene and boron nitride heterostructure creates large spin signals

16.08.2017 | Materials Sciences

A new method for the 3-D printing of living tissues

16.08.2017 | Interdisciplinary Research

VideoLinks
B2B-VideoLinks
More VideoLinks >>>