Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Carbon dioxide biggest player in thawing permafrost

14.06.2016

Carbon dioxide emissions from dry and oxygen-rich environments will likely strengthen the climate forcing impact of thawing permafrost on top of methane release from oxygen-poor wetlands in the Arctic, according to a study in Nature Climate Change.

The study, published today, was led by Northern Arizona University assistant research professor, Christina Schädel. One of her collaborators is Evan Kane, an assistant professor of soils at Michigan Technological University.


To better understand the impact of methane and carbon dioxide on climate change, ecologist Evan Kane samples thawing permafrost in Alaska.

Credit: Michigan Tech, Evan Kane

"Having the chance to be involved with such a large collaboration is important," Kane says, adding that getting a more complete understanding of the impacts of thawing permafrost requires a lot of researchers. "With this study, we're able to look at the complexity of the changing permafrost environments and offer more insight into how the carbon they hold will react as they thaw."

Greenhouse Gases

Schädel's meta-analysis of 25 Arctic soil incubation studies found that both temperature and soil conditions affected the quantity of carbon released from thawing permafrost. A 10 °C increase in soil temperature released twice as much carbon into the atmosphere, and drier, aerobic soil conditions released more than three times more carbon than wetter, anaerobic soil conditions.

Most of that carbon was in the form of carbon dioxide, mixed with a surprisingly small amount of methane--only 5 percent of the total anaerobic products. This means that even though methane packs 34 times the climate warming punch of carbon dioxide, the small quantity released relative to carbon dioxide in anaerobic conditions makes wet soils less of a concern than dry soils.

"Our results show that increasing temperatures have a large effect on carbon release from permafrost but that changes in soil moisture conditions have an even greater effect," says Schädel. "We conclude that the permafrost carbon feedback will be stronger when a larger percentage of the permafrost zone undergoes thaw in a dry and oxygen-rich environment. "

Thawing Permafrost

Scientists in the international Permafrost Carbon Network that Schädel co-leads with Northern Arizona University professor of ecosystem ecology, Ted Schuur, provided much of the data.

Kane helped provide data on how altered hydrology, specifically flooding and drought, affects organic matter decomposition. He and his team observed that the carbon dioxide to methane ratios were impacted by dry or wet soils, with carbon dioxide production favored in drying and variable scenarios. The initial findings, included in the new meta-analysis, were originally published in Soil Biology & Biogeochemistry.

As the permafrost thaws, microbes wake up and begin digesting the newly available remains of ancient plants and animals stored as carbon in the soil. This digestion produces either carbon dioxide or methane, depending on soil conditions. Scientists want to understand the ratio of carbon dioxide to methane gas released by this process because it affects the strength of the permafrost carbon feedback loop: greenhouse gases released due to thawing permafrost cause temperatures to rise, leading to even more thawing and carbon release. Furthermore, the Arctic permafrost is like a vast underground storage tank of carbon, holding almost twice as much as the atmosphere. At that scale, small changes in how the carbon is released will have big effects.

Schädel zeroed in on two factors: soil temperature and the availability of oxygen. Soils in the lab were incubated at a range of warmer temperatures projected for the future. The availability of oxygen is important because it determines how microbes digest carbon. Oxygen-rich, or aerobic, conditions are found in dry soils and produce carbon dioxide. Oxygen-poor, or anaerobic, conditions are found in wet soils and produce both carbon dioxide and methane. Lab incubations mimicked these two conditions.

Will wet or dry soils dominate the future Arctic permafrost zone? The answer to this question is a big unknown. Schädel's work, however, will strengthen existing models of the permafrost ecosystem. Her work also highlights the need to monitor changes in wetness associated with permafrost thaw, changes that ultimately sculpt the topography of waterlogged depressions and dry uplands across the Arctic landscape.

Media Contact

Christina Schadel
Christina.Schaedel@nau.edu
928-523-9588

 @michigantech

http://www.mtu.edu 

Christina Schadel | EurekAlert!

More articles from Earth Sciences:

nachricht Boreal forest fires could release deep soil carbon
22.08.2019 | NASA/Goddard Space Flight Center

nachricht An Ice Age savannah corridor let large mammals spread across Southeast Asia
22.08.2019 | Eberhard Karls Universität Tübingen

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Hamburg and Kiel researchers observe spontaneous occurrence of skyrmions in atomically thin cobalt films

Since their experimental discovery, magnetic skyrmions - tiny magnetic knots - have moved into the focus of research. Scientists from Hamburg and Kiel have now been able to show that individual magnetic skyrmions with a diameter of only a few nanometres can be stabilised in magnetic metal films even without an external magnetic field. They report on their discovery in the journal Nature Communications.

The existence of magnetic skyrmions as particle-like objects was predicted 30 years ago by theoretical physicists, but could only be proven experimentally in...

Im Focus: Physicists create world's smallest engine

Theoretical physicists at Trinity College Dublin are among an international collaboration that has built the world's smallest engine - which, as a single calcium ion, is approximately ten billion times smaller than a car engine.

Work performed by Professor John Goold's QuSys group in Trinity's School of Physics describes the science behind this tiny motor.

Im Focus: Quantum computers to become portable

Together with the University of Innsbruck, the ETH Zurich and Interactive Fully Electrical Vehicles SRL, Infineon Austria is researching specific questions on the commercial use of quantum computers. With new innovations in design and manufacturing, the partners from universities and industry want to develop affordable components for quantum computers.

Ion traps have proven to be a very successful technology for the control and manipulation of quantum particles. Today, they form the heart of the first...

Im Focus: Towards an 'orrery' for quantum gauge theory

Experimental progress towards engineering quantized gauge fields coupled to ultracold matter promises a versatile platform to tackle problems ranging from condensed-matter to high-energy physics

The interaction between fields and matter is a recurring theme throughout physics. Classical cases such as the trajectories of one celestial body moving in the...

Im Focus: A miniature stretchable pump for the next generation of soft robots

Soft robots have a distinct advantage over their rigid forebears: they can adapt to complex environments, handle fragile objects and interact safely with humans. Made from silicone, rubber or other stretchable polymers, they are ideal for use in rehabilitation exoskeletons and robotic clothing. Soft bio-inspired robots could one day be deployed to explore remote or dangerous environments.

Most soft robots are actuated by rigid, noisy pumps that push fluids into the machines' moving parts. Because they are connected to these bulky pumps by tubes,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

The power of thought – the key to success: CYBATHLON BCI Series 2019

16.08.2019 | Event News

4th Hybrid Materials and Structures 2020 28 - 29 April 2020, Karlsruhe, Germany

14.08.2019 | Event News

What will the digital city of the future look like? City Science Summit on 1st and 2nd October 2019 in Hamburg

12.08.2019 | Event News

 
Latest News

Making small intestine endoscopy faster with a pill-sized high-tech camera

23.08.2019 | Medical Engineering

More reliable operation offshore wind farms

23.08.2019 | Power and Electrical Engineering

Tracing the evolution of vision

23.08.2019 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>