New study uses CMIP5 historical simulations to find out more about Arctic sea ice decline and ice export

Current Arctic sea ice (bluish white) compared with the 1979-2010 average sea ice minimum (outlined in orange). The red arrow is superimposed to indicate the southward export of sea ice through the Fram Strait. Credit: SVS/NASA The Arctic sea ice is shrinking, both in extent and thickness. In addition to the manmade contribution to the sea ice loss, there are also natural factors contributing to this loss. In a new study from the Bjerknes Centre we focus on one of these factors: the ice export through the large gateway between Greenland and Svalbard—the Fram Strait.

 

Read more at: http://phys.org/news/2013-01-cmip5-historical-simulations-arctic-sea.html#jCp

Larger than the United Kingdom 

Most of the sea ice that leaves the Arctic, exits through the Fram Strait. In recent years, this ice export has been higher than in any decade between the late 1950s and up to today. The area of the ice floating through the Fram Strait is now about 200 thousand km2 larger than in the late 1950s, which is similar to the total area of the United Kingdom. This increase in the export contributes to the Arctic sea ice loss, as shown in a recent study (Smedsrud et al., 2008). Our climate models also show that the Arctic is loosing sea ice, but it is not known how they represent the ice export in the Fram Strait. Reproduces a realistic seasonal cycle of the ice export We have therefore investigated the ice export in 6 current climate models that provides 24 different simulations. Perhaps surprisingly, most of these coarse resolution models manage to reproduce a realistic seasonal cycle of the ice export, with more ice floating through the strait during winter than summer. On the other hand, not all simulations show an increase in the ice export from the late 1950s and up to today. Some simulations actually show a decrease in the ice export. Not governed by external forcing Because the simulations do not show similar behaviour, we interpret that changes in the ice export is not governed by external forcing, such as changes in the CO2 concentration or changes in the incoming sunlight. The ice export is rather controlled by internal climate variability within each model, for instance, variability in the wind pattern over the Arctic. The spread in the simulations from one model indicate the extent of the internal climate variability in that model. Because the models show different outcomes for the ice export, it is possible to investigate how the Arctic sea ice responds to an increase or decrease in the export. According to the model with the largest number of simulations (10), we find that a thinning of the Arctic sea ice is associated with an increase in the ice export, whereas a decrease in the ice export is related to a smaller thinning. All simulations underestimate the thinning of the Arctic sea ice compared to observations. This means that the simulations would have been closer to the reality today if they were able to reproduce the increase in the Fram Strait ice export. More information: Langehaug, H., et al., Arctic sea ice decline and ice export in the CMIP5 historical simulations. Ocean Modelling (Arctic Ocean Special Issue), doi: 10.1016/j.ocemod.2012.12.006, In Press. Smedsrud, L., et al., 2011. Recent wind driven high sea ice area export in the Fram Strait contributes to Arctic sea ice decline. The Cryosphere 5, 821-829. Journal reference: The Cryosphere Provided by University of Bergen 

Read more at: http://phys.org/news/2013-01-cmip5-historical-simulations-arctic-sea.html#jCp

Associated companies:


Related news

Latest news

UiB and CMR in high-tech collaboration

Students from UiB last month joined an experiment with an ultra-high-speed camera. This was a part of the troubleshooting of the Field Kelvin Probe currently under development.

Hatteland Display at International Workboat Show 2016

Hatteland Display are highlighting its diverse portfolio of maritime displays and panel computers on its booth (#1658) at the International Workboat Show 2016 (IWBS 2016) this week.

Servogear Announces Upcoming Events

Servogear announces a busy end of November, beginning of December. They will be participating at important international exhibitions.

Teamtec and ANDRITZ Cooperation

ANDRITZ and TeamTec have signed a cooperation agreement for worldwide marketing of the SeaSOx exhaust gas cleaning system for the maritime industry. 

Export Credit Norway looking for Norway's Best Exporter

Export Credit Norway  has now opened the nomination process for the 2017 Export Award, searching the Norwegian exporter of the year. 

Global Economic Outlook

7 December, Oslo Chamber of Commerce invites to a session with insightful updates on the Norwegian and international economy.

Rebuilding for Hydrogen

M/Y “Che Guevara”, previously owned by Gaddafi, will be converted to run on hydrogen. Greenstat will lead the project and are seeking partners.

Scana training at Servogear

In week 43-45 Servogear  had the pleasure of having Mr. Sun Xiaojia and Mr. Tzuu Kin Tan from Scana staying in the Servogear hometown of Rubbestadneset.

Quality and Customer Satisfaction

Cost efficiency is important. But we can’t rely on cost-cutting alone. At Beerenberg we have asked ourselves the following question: What does it take for the market to continue to choose providers such as Beerenberg in th...