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© Stefan Hendricks, AWIPolaris in the polar night of the Antarctic winter
Translated by Google from this press release in German at the Alfred Wegener Institute in Germany:

Never so much sea ice at Antarctica in the last 30 years

In light of global warming, it seems paradoxical that the sea ice cover of the Southern Ocean has covered a larger area in the past month than in the last decades. Only in the mid-70s was observed a similar expansion.

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Average sea ice extent in September (1973-2013) with trend line

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Seasonal variability of sea ice extent (as at 13.10.2013)
The means were 19.48 million in September 2013 square kilometers, an area once covered more than 50 times larger than Germany with sea ice. The absolute maximum of 19.65 million square kilometers was reached on 18 of September. Although this maximum in the ice-covered surface can not be equated with a maximum of the total volume or mass, suggest that sea ice physicist Marcel Nicolaus and Stefan Hendricks from the Alfred Wegener Institute (AWI) "This winter there is in Antarctica as much ice as long gone, if it has ever been since the beginning of the regular satellite observations ever so much sea ice."

To be able to make such statements in certain future, the researchers of the Alfred Wegener Institute is currently also the thickness of sea ice in the Antarctic work together with colleagues from different institutions that they can derive from satellite observations. In the Arctic, it has recently become possible, although there are significant differences between Arctic and Antarctic. The snow is thick, inhomogeneous and does not melt completely in summer. In addition, sea ice is formed at the top, a phenomenon that is encountered less frequently in the Arctic. Then there can also be calculated from the thickness and extent of sea ice volume in the future.

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Minimum sea ice concentration on 22 February 2013

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Sea ice concentration maximum at 18 September 2013
The ice-covered area of ​​the Antarctic Ocean grows each year by its minimum at the end of the Antarctic summer (February) of three to four million square kilometers on a multiple (approximately five to six times as much) to the maximum at the end of winter (September). Here, however, there are big regional differences, so that the Antarctic sea ice to be regarded as really a puzzle of different ice cover and assess.

Although over the last few years an increase in the total ice cover in winter and summer is observed, for example, it takes the tip of the Antarctic Peninsula, especially in the summer from clear. While the Antarctic Peninsula has warmed significantly in recent decades, the temperature remained stable in other regions.

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© Sandra Schwegmann, AWIAutomatic measuring station for measuring the snow depth on sea ice (Schneeboje) during the polar night. Applied during the winter experiment
These differences and the general increase of sea ice in many areas resulting in large part from changes in the wind that drives the sea ice more apart. On the other hand the temperatures and winds from the Antarctic continent have a strong impact on the sea ice belt around him. These are also differences to the Arctic, which contributes that the sea ice behaves so differently in both polar regions.

To better understand all of these contexts, the AWI has conducted two winter experiments with the research icebreaker Polarstern in the Weddell Sea in recent months. In these expeditions, the scientists have ever encountered thick, compact ice, after which they base their theory of the maximum of the ice mass. In addition to measurements during the trip, a variety of automatic measuring stations was deployed on the sea ice. This now continuously measure the thickness, temperature and movement of sea ice and its snow cover and send their data via satellite to the AWI and other project partners.

Reports, photographs, maps and data of these experiments are here presented and commented. More information is also available on the fact sheet on sea ice as well as the websites of the sea ice physics section available.

Pierre Gosselin at No Tricks Zone has a better translation and some additional commentary here: Stunner: Germany's Alfred Wegener Institute Confirms Antarctic Sea Ice May Have Reached Record VOLUME!