Ongoing Retreat in the Arctic, new maximum in the Antarctic
The area of sea ice in the Arctic fell to a summer minimum of around 5.0 million square kilometres this year, which is about 1.6 million square kilometres more than the record low in 2012. However, according to sea ice physicist Marcel Nicolaus from the Alfred Wegener Institute (AWI) and Lars Kaleschke from the Hamburg Cluster of Excellence for Climate Research (CliSAP) this confirms the long-term downward trend in the Arctic.
Arctic, 31. August 2014: Scientists take sea ice samples out of Polarstern's mummy chair.
Photo: Ruediger Stein / Alfred Wegener Institute
On the other hand, the winter ice sheet in the South Polar Ocean has expanded to an area of 20.0 million square kilometres, as the researchers report, which exceeds the 30-year-maximum from the previous year. This Thursday, September 18, Marcel Nicolaus, Lars Kaleschke and other leading sea ice experts will be available for discussions and interviews at an international sea ice symposium in Hamburg.
“The current minimum sea ice in the Arctic illustrates the continuation of a long-term downward trend. With an area of 5.0 million square kilometres, the 2014 minimum approximately equals last year’s minimum. This by no means represents a trend reversal in Arctic sea ice developments – despite the fact that the remaining sea ice area is larger than in the two ‘extreme years’ 2007 and 2012,” says sea ice physicist Marcel Nicolaus from the Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research.
In the negative-record years, weather phenomena led to a particularly large reduction in sea ice. “In 2007, a stable high pressure area in early summer resulted in numerous melt pools forming on the ice. They absorbed energy from the sun, which further intensified the melting. In summer 2012, there was exceptional melting on the underside of the ice, and in August that year there was a severe storm, which stirred up the ice. Such extreme weather was largely absent in 2014,” explains Lars Kaleschke from the Hamburg Cluster of Excellence for Climate Research CliSAP.
Large Regional Differences
In the last few weeks, there have been unusually marked regional differences in ice development. For example: In the last two weeks of August, on its way to the region of the undersea mountain chain Alpha Ridge, the German research icebreaker Polarstern was unable to break the ice north of the Canadian Archipelago, while the ice in the Russian Laptev Sea retreated further north than ever before observed by satellites. “In the first days of September, the ice edge in the Laptev Sea was north of the 85th parallel, only about 500 km from the North Pole. In 2006, the distance from the North Pole to open sea was more than more than twice that,” says Lars Kaleschke.
Expanding Ice Sheets in the Antarctic
There are currently exceptionally large areas of sea ice in the Antarctic, where the ice sheet generally reaches its spring maximum in September or October. “At the moment, ice covers a sea area of around 20 million square kilometres and therewith exceeds the 30-year-maximum of 19.65 million square kilometres from the previous year. This data backs up our observation that sea ice coverage in the Antarctic has increased in recent years. This is especially true for the Weddell Sea, where we do most of our research,” says Marcel Nicolaus.
However, the researchers do not feel the sea ice situation in the Antarctic can be compared with the conditions in the Arctic, given the differences in their geographical and meteorological circumstances. “Whereas the Arctic Ocean represents a Mediterranean of sorts surrounded by land masses, what we see in the Antarctic is an ice-covered continent surrounded by the Southern Ocean. Here the Antarctic Circumpolar Current limits the maximum sea ice expansion. Wind and waves greatly influence the ice edge – and the amounts of precipitation and glacial meltwater determine the percentage of fresh water, which in turn helps to determine how much sea ice forms in winter,” explains Lars Kaleschke.
The international scientific community is currently discussing a variety of factors as possible explanations for the major expansion of Antarctic sea ice. For example, the growth in area could have been set off by changed wind currents and rising meltwater. (For more on this discussion, visit our sea ice portal: http://bit.ly/1rtLX44 )
Invitation to the Symposium in Hamburg
Lars Kaleschke, Marcel Nicolaus and other international sea ice experts will meet this Thursday and Friday (Sept. 18-19, 2014) at a sea ice symposium in Hamburg, which will primarily focus on satellite-assisted ice measurement. The researchers hope to develop methods that will allow them to combine a variety of different satellite datasets to generate reliable and mutually comparable long-term data series on sea ice expansion, concentration and thickness. (For details on the workshop, please see: http://www.climate-cryosphere.org/meetings/seaice-conc-2014)
Interested journalists are warmly invited to use the workshop as an opportunity to talk with the researchers, who will be available for interviews on sea ice from 2:00 p.m. to 4:30 p.m. on Thursday, September 18, 2014. For more information, please contact Markus Dressel at the Public Relations Office for the Cluster of Excellence CliSAP (contact details below).
The workshop will be held at the Center for Earth System Research and Sustainability (CEN), Universität Hamburg, Bundessstraße 53, 20146 Hamburg (formerly the ZMAW building).
Notes for Editors:
We will be pleased to provide contact information for the participating researchers on request.
Our multimedia resources:
• The latest sea ice maps and time series from the Arctic and Antarctic: http://www.awi.de/en/news/press_releases/
• Sea ice photographs from the Arctic and Antarctic: http://www.awi.de/de/aktuelles_und_presse/bild_film_ton/bildergalerien/fotogalerie_meereis/
• Animation: Sea ice development in the course of 2013 – the Arctic and Antarctic in comparison: http://www.youtube.com/watch?v=55p5ygKgxio&list=PLFCwd9Up8tvCdlCyXKSWxggqim0gy3TLw
• AWI Fact Sheet on sea ice (released September 2013): http://www.awi.de/de/aktuelles_und_presse/hintergrund/ipcc/fact_sheet_meereis/
Your academic contact partners are:
• Dr. Marcel Nicolaus (tel.: +49 471 4831-2905, e-mail: Marcel.Nicolaus(at)awi.de)
• Prof. Dr. Lars Kaleschke, (tel.: +49 40 42838-6518, e-mail: lars.kaleschke(at)uni-hamburg.de )
At the press offices of the Alfred Wegener Institute and the Cluster of Excellence CliSAP, the following contact partners will be happy to assist you:
• Sina Löschke, Alfred Wegener Institute (tel: +49 471 4831-2008; e-mail: medien(at)awi.de)
• Markus Dressel, CliSAP/CEN (tel: +49 40 42838-7596, e-mail: markus.dressel(at)uni-hamburg.de)
Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung | idw - Informationsdienst Wissenschaft
Water - as the underlying driver of the Earth’s carbon cycle
17.01.2017 | Max-Planck-Institut für Biogeochemie
Modeling magma to find copper
13.01.2017 | Université de Genève
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).
Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...
10.01.2017 | Event News
09.01.2017 | Event News
05.01.2017 | Event News
18.01.2017 | Power and Electrical Engineering
18.01.2017 | Materials Sciences
18.01.2017 | Life Sciences