Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

The tundra -- a dark horse in planet Earth's greenhouse gas budget

10.10.2013
The Arctic tundra may become a source of CO2 as the climate becomes warmer

Vast areas on the Northern Hemisphere are covered by tundra. Here, dwarf shrubs, sedges, mosses etc. thrive on top of permafrost in areas where only the uppermost soil layer thaws during the short Arctic summer.


Zackenberg Research Station in Northeast Greenland was established in 1995 and has since become one of the best platforms for research and monitoring in the Arctic thanks to the ongoing monitoring programs. The buildings in Zackenberg are owned by Greenland's Self Government, whereas operation and maintenance are undertaken by Aarhus University.

Credit: Henrik Spanggård Munch, Aarhus University

New studies show that the tundra may become a source of CO2 in the future. Researcher Magnus Lund from Aarhus University explains:

"The soil below the tundra contains very large quantities of carbon – more than twice as much as is present in the planet's entire atmosphere. Therefore, we would like to know if the carbon will stay put – or if it will be released into the atmosphere as CO2 or methane as the climate warms."

Since 2000, researchers in Zackenberg in Northeast Greenland have therefore studied the carbon balance by exploring the following two figures:

1) The amount of carbon released in the form of CO2 as living organisms respire

2) The amount of carbon being stored in plants owing to photosynthesis.

Once you have established the two figures, it is possible to calculate if the tundra is a source of CO2 or if it acts as a sink absorbing carbon and storing it in living plants or in the peat layer.

"We can see that the annual release of CO2 from living organisms increases linearly as the temperature increases, measured as the average temperature in July. However, it seems that the ability of the photosynthesis to assimilate carbon stops increasing when the temperature in July rises above approx. seven degrees Celsius, which has occurred several times in past years. This means that the tundra may become a CO2 source if the current strong climate warming continues as expected," says Magnus Lund, before pointing out that the fear that the tundra can develop into a source of CO2 is based on a very limited number of measurements.

"It's a problem in the Arctic that we don't perform measurements at enough locations. The variation between locations is substantial both for CO2 and not least for methane. In Greenland, we measure near Nuuk and in Zackenberg, where we collect measurements from a relatively dry heath and from a moist fen area. A new station is also being established at Station Nord in the northernmost part of Greenland."

Methane remains more important

Magnus Lund emphasises that, in decades to come, from an Arctic perspective, methane will remain the primary contributor to Earth's greenhouse gas budget. In 2007, researchers from the Zackenberg research station in Northeast Greenland made a surprising discovery: In autumn, when the surface of the tundra freezes and ice is formed, large quantities of the powerful greenhouse gas methane are released. In fact, the quantities released were so large, that the annual methane emissions had to be doubled in the calculation of the tundra's methane budget.

Methane is a powerful greenhouse gas, its effect is 20-25 times as strong as that of CO2. Methane, therefore, still plays a central role for the research performed at Zackenberg.

Soil moisture crucial

Recent studies have shown that the formation of methane is closely linked to the tundra's water content - as implied by the term "swamp gas". The more water is present in the tundra, the more methane is formed. And vice versa, where there is less water, the presence of oxygen will provide the basis for formation of CO2. In this way, the soil's water content plays an important role in determining what will happen with the carbon below the tundra.

Areas that become drier will give rise to increased CO2 emissions, whereas areas that become more moist will cause the emissions of methane to increase. The water balance is affected by the temperature and precipitation, but also by the soil's content of ice.

Among other things, researchers are now working to establish how and when the methane released in autumn is formed, and if this involves new or old carbon.

Zackenberg Research Station in Northeast Greenland was established in 1995 and has since become one of the best platforms for research and monitoring in the Arctic thanks to the ongoing monitoring programmes. The buildings in Zackenberg are owned by Greenland's Self Government, whereas operation and maintenance are undertaken by Aarhus University.

Photo: Measuring equipment

Measuring equipment in Rylekæret fen, Zackenberg. The lawn-chair-like devices at the end of the boardwalk measure the exchange of methane and CO2 between the fen and the atmosphere. To the left: a gradient system for measurement of the exchange of methane between the tundra and the atmosphere. Even though many of the measurements can now be made automatically, it is necessary to check the equipment regularly to ensure that everything is in good working order. Photo: Laura Helene Rasmussen, Aarhus University.

Contact

Researcher Magnus Lund
Aarhus University
Department of Bioscience and Arctic Research Centre
tel. (+45) 3078 3178
ml@dmu.dk
Read more
Trends in CO2 exchange in a high Arctic tundra heath, 2000–2010. M. Lund et al. 2012, Journal of Geophysical Research, vol. 117, G02001, doi:10.1029/2011JG001901, 2012

Revisiting factors controlling methane emissions from high-Arctic tundra. M. Mastepanov et al. 2013, Biogeosciences, vol. 10, 5139–5158, 2013, doi:10.5194/bg-10-5139-2013

Researchers predict a greener Greenland, http://scitech.au.dk/en/current-affairs/news/show/artikel/researchers-predict-a-greener-greenland/ (news article from Aarhus University)

Zackenberg Research Station, http://www.zackenberg.dk/

PLANET EARTH IS GETTING HOTTER- BUT WHAT CAN WE DO ABOUT IT? Theme on Climate Change at Aarhus University, http://newsroom.au.dk/en/themes/theme-climate-change/

Magnus Lund | EurekAlert!
Further information:
http://www.dmu.dk

Further reports about: Arctic Ocean CO2 CO2 emission Greenland Zackenberg living organism methane emissions

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: A Challenging European Research Project to Develop New Tiny Microscopes

The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.

To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Researchers shoot for success with simulations of laser pulse-material interactions

29.03.2017 | Materials Sciences

Igniting a solar flare in the corona with lower-atmosphere kindling

29.03.2017 | Physics and Astronomy

As sea level rises, much of Honolulu and Waikiki vulnerable to groundwater inundation

29.03.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>