Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Arctic sea ice declines again in 2004

05.10.2004


Researchers at the University of Colorado at Boulder have found that the extent of Arctic sea ice, the floating mass of ice that covers the Arctic Ocean, is continuing its rapid decline.



The latest satellite information indicates the September 2004 sea ice extent was 13.4 percent below average, a reduction in area nearly twice the size of Texas, said Mark Serreze of CU-Boulder’s National Snow and Ice Data Center, or NSIDC. In 2002, the decline in arctic sea ice during September -- which traditionally marks the end of the summer melt season -- was about 15 percent, a record low, said CU-Boulder researcher Walt Meier of NSIDC.

The decline in sea ice extent during September has averaged about 8 percent over the past decade, said Serreze, who is part of a CU-Boulder team monitoring Arctic sea-ice conditions. "This is the third year in a row with extreme ice losses, pointing to an acceleration of the downward trend," he said.


"While a ’low’ September ice extent one year is often followed by a recovery the next year, this was not the case in 2003, which was about 12 percent below average," Serreze said. The September 2004 sea-ice loss was especially evident in extreme northern Alaska and eastern Siberia. The CU-Boulder researchers used remote-sensing data from the SSMI satellite to record the sea-ice changes. "We’re seeing more melting of multi-year ice in the summer," said Julienne Stroeve, a CU-Boulder scientist with NSIDC involved in the research. "We may soon reach a threshold beyond which the sea ice can no longer recover." NSIDC is part of CU-Boulder’s Cooperative Institute for Research in Environmental Sciences.

One possible explanation for the continuing loss of sea ice is that climate warming from human activities like the burning of fossil fuels is becoming more apparent, said Serreze. "Climate models are in general agreement that one of the strongest signals of greenhouse warming will be a loss of Arctic sea ice," he said. "Some indicate complete disappearance of the summer sea ice cover by 2070."

Serreze believes natural climate variability likely plays some part in the observed changes. "However, the most reasonable view is that the sea ice decline represents a combination of both natural variability and the greenhouse effect, with the latter becoming more evident in coming decades," he said.

One complicating factor is the atmospheric circulation pattern known as the Arctic Oscillation, which may be contributing to the loss of the much thicker "multi-year" ice that has accumulated over many years. "As winds and currents force this ice southward, more of it melts," said Stroeve. "And while new ice is still forming in the winters, it is thinner, and therefore melts faster in the summer than older ice."

In a study funded by the National Science Foundation conducted with assistance from CU-Boulder, former graduate student Shari Fox Gearheard looked at the effects of climate change on Inuit communities in the Arctic region. "The timing of the climate and environmental changes observed by Inuit in Nunavut vary depending on the phenomenon, but in many cases elders and other experienced Inuit point to the last decade as a period of considerable change," Gearheard said. Nunavut is a Canadian Territory established in 1999 that is roughly the size of Western Europe.

Gearheard said one of the most frequent observations in indigenous communities all across the circumpolar north is that the weather is more unpredictable than usual. "In the past, Inuit were able to predict the weather using traditional indicators such as clouds, winds and currents," she said. "These indicators are no longer working."

Inuit elders point out that the sea ice in some places is thinner, causing dangerous travel conditions, she said. The ice forms later and breaks up earlier in the year, and the spring melt season is much shorter than before. In addition, unexpected storms have left hunting parties stranded, and harder packed snow due to recent wind changes makes it more difficult to build igloos for shelter.

The results of Gearheard’s work are presented in an interactive multimedia CD titled "When the Weather is Uggianaqtuq: Inuit observations of environmental change." Uggianaqtuq is a North Baffin Inuktitut word meaning to behave unexpectedly or in an unfamiliar way.

Another CU-Boulder project involves the effects of climate change on North Slope communities in Alaska, including the effects of loss of ice cover on the potential for increased damage, erosion and flooding from severe storms. CU-Boulder researchers Jim Maslanik of NSIDC said the retreat of the protective ice edge further offshore later into autumn has increased the potential for flooding and erosion for coastal communities such as Barrow. "Another aspect of the changing ice conditions is that, in addition to the ice edge retreating far offshore, the rate of retreat of the ice edge has been very rapid," said Maslanik. "In recent years, this has resulted in unexpected impacts, such as unusually large numbers of polar bears being stranded on shore near Barrow."

Mark Serreze | EurekAlert!
Further information:
http://www.colorado.edu
http://nsidc.org

More articles from Ecology, The Environment and Conservation:

nachricht Safeguarding sustainability through forest certification mapping
27.06.2017 | International Institute for Applied Systems Analysis (IIASA)

nachricht Dune ecosystem modelling
26.06.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

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

Im Focus: Manipulating Electron Spins Without Loss of Information

Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.

For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...

Im Focus: The proton precisely weighted

What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.

To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...

Im Focus: On the way to a biological alternative

A bacterial enzyme enables reactions that open up alternatives to key industrial chemical processes

The research team of Prof. Dr. Oliver Einsle at the University of Freiburg's Institute of Biochemistry has long been exploring the functioning of nitrogenase....

Im Focus: The 1 trillion tonne iceberg

Larsen C Ice Shelf rift finally breaks through

A one trillion tonne iceberg - one of the biggest ever recorded -- has calved away from the Larsen C Ice Shelf in Antarctica, after a rift in the ice,...

Im Focus: Laser-cooled ions contribute to better understanding of friction

Physics supports biology: Researchers from PTB have developed a model system to investigate friction phenomena with atomic precision

Friction: what you want from car brakes, otherwise rather a nuisance. In any case, it is useful to know as precisely as possible how friction phenomena arise –...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Closing the Sustainability Circle: Protection of Food with Biobased Materials

21.07.2017 | Event News

»We are bringing Additive Manufacturing to SMEs«

19.07.2017 | Event News

The technology with a feel for feelings

12.07.2017 | Event News

 
Latest News

NASA looks to solar eclipse to help understand Earth's energy system

21.07.2017 | Earth Sciences

Stanford researchers develop a new type of soft, growing robot

21.07.2017 | Power and Electrical Engineering

Vortex photons from electrons in circular motion

21.07.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>