Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Effects of climate change in the Arctic are 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, please contact:
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

Megan Grindlay | idw
Further information:
http://amap.no/Conferences/Conf2011/
http://www.vr.se

More articles from Earth Sciences:

nachricht How much biomass grows in the savannah?
16.02.2017 | Friedrich-Schiller-Universität Jena

nachricht Canadian glaciers now major contributor to sea level change, UCI study shows
15.02.2017 | University of California - Irvine

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Switched-on DNA

20.02.2017 | Materials Sciences

Second cause of hidden hearing loss identified

20.02.2017 | Health and Medicine

Prospect for more effective treatment of nerve pain

20.02.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>