Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Effects of climate change in the Arctic more extensive than expected

05.05.2011
A much reduced covering of snow, shorter winter season and thawing tundra. The effects of climate change in the Arctic are already here. And the changes are taking place significantly faster than previously thought. This is what emerges from a new research report on the Arctic, presented in Copenhagen this week. Margareta Johansson, from Lund University, is one of the researchers behind the report.
Together with Terry Callaghan, a researcher at the Royal Swedish Academy of Sciences, Margareta is the editor of the two chapters on snow and permafrost.

“The changes we see are dramatic. And they are not coincidental. The trends are unequivocal and deviate from the norm when compared with a longer term perspective”, she says.

The Arctic is one of the parts of the globe that is warming up fastest today. Measurements of air temperature show that the most recent five-year period has been the warmest since 1880, when monitoring began. Other data, from tree rings among other things, show that the summer temperatures over the last decades have been the highest in 2000 years. As a consequence, the snow cover in May and June has decreased by close to 20 per cent. The winter season has also become almost two weeks shorter – in just a few decades. In addition, the temperature in the permafrost has increased by between half a degree and two degrees.

“There is no indication that the permafrost will not continue to thaw”, says Margareta Johansson.

Large quantities of carbon are stored in the permafrost.

“Our data shows that there is significantly more than previously thought. There is approximately double the amount of carbon in the permafrost as there is in the atmosphere today”, says Margareta Johansson.

The carbon comes from organic material which was “deep frozen” in the ground during the last ice age. As long as the ground is frozen, the carbon remains stable. But as the permafrost thaws there is a risk that carbon dioxide and methane, a greenhouse gas more than 20 times more powerful than carbon dioxide, will be released, which could increase global warming.

“But it is also possible that the vegetation which will be able to grow when the ground thaws will absorb the carbon dioxide. We still know very little about this. With the knowledge we have today we cannot say for sure whether the thawing tundra will absorb or produce more greenhouse gases in the future”, says Margareta Johansson.

Effects of this type, so-called feedback effects, are of major significance for how extensive global warming will be in the future. Margareta Johansson and her colleagues present nine different feedback effects in their report. One of the most important right now is the reduction of the Arctic’s albedo. The decrease in the snow- and ice-covered surfaces means that less solar radiation is reflected back out into the atmosphere. It is absorbed instead, with temperatures rising as a result. Thus the Arctic has entered a stage where it is itself reinforcing climate change.

The future does not look brighter. Climate models show that temperatures will rise by a further 3 to 7 degrees. In Canada, the uppermost metres of permafrost will thaw on approximately one fifth of the surface currently covered by permafrost. The equivalent figure for Alaska is 57 per cent. The length of the winter season and the snow coverage in the Arctic will continue to decrease and the glaciers in the area will probably lose between 10 and 30 per cent of their total mass. All this within this century and with grave consequences for the ecosystems, existing infrastructure and human living conditions.

New estimates also show that by 2100, the sea level will have risen by between 0.9 and 1.6 metres, which is approximately twice the increase predicted by the UN’s panel on climate change, IPCC, in its 2007 report. This is largely due to the rapid melting of the Arctic icecap. Between 2003 and 2008, the melting of the Arctic icecap accounted for 40 per cent of the global rise in sea level.

“It is clear that great changes are at hand. It is all happening in the Arctic right now. And what is happening there affects us all”, says Margareta Johansson.

The report “Impacts of climate change on snow, water, ice and permafrost in the Arctic” has been compiled by close to 200 polar researchers. It is the most comprehensive synthesis of knowledge about the Arctic that has been presented in the last six years. The work was organised by the Arctic Council’s working group for environmental monitoring (the Arctic Monitoring and Assessment Programme) and will serve as the basis for the IPCC’s fifth report, which is expected to be ready by 2014.

Besides Margareta Johansson, Torben Christensen from Lund University also took part in the work.

For more information:
Margareta Johansson, Division of Physical Geography and Ecosystems Analysis, Lund University, telephone: 046-2224480, mobile: 070-6842965, email: Margareta.Johansson@nateko.lu.se
Terry Callaghan, Royal Swedish Academy of Sciences, email: terry_callaghan@btinternet.com
Read more information on the report and The Artic as a messenger for global processes - climate change and pollution conference in Copenhagen where it is being presented today.

- Ulrika Jönsson Belyazid

Margareta Johansson | EurekAlert!
Further information:
http://www.lu.se

More articles from Earth Sciences:

nachricht Early organic carbon got deep burial in mantle
25.04.2017 | Rice University

nachricht New atlas provides highest-resolution imagery of the Polar Regions seafloor
25.04.2017 | British Antarctic Survey

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

NASA's Fermi catches gamma-ray flashes from tropical storms

25.04.2017 | Physics and Astronomy

Researchers invent process to make sustainable rubber, plastics

25.04.2017 | Materials Sciences

Transfecting cells gently – the LZH presents a GNOME prototype at the Labvolution 2017

25.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>