Sunday, November 3, 2013

Slicing the ice

23rd of October, we spotted our first iceberg !

As our way is mainly Westerly, it took us a week to enter into the sea ice. And the landscape is worth the voyage ! For almost half of the expeditioners, the white world is a new discovery and makes for great excitement after a week at sea.

At this time of the season, the pack ice starts opening, and the icebergs stuck in the ice during the winter are released. They then sail Westerly, following the main coastal current and finally end up meeting the ship North of the continent.



  



The sea ice is still thick, and spread widely compared to previous years. In front of Davis, the ice is extending to 55°S, a record for this time of year. Our progression until 61°S has been relatively good, as the last windy days opened rivers in the pack ice, and spread the pieces. But as we are now approaching 62°S, our progression has slowed considerably. The most concentrated ice, results from the compression of sea-ice around Davis, and should be crossed in the next two or three days.

The types of sea ice encountered vary depending on its age (from the first year sea-ice to the multi year fast ice) and on external conditions. The first type is the frazil, fine spicules of ice suspended in the water, giving it a kind of oily appearance. Once the crystals have coagulated, they form grease ice (grey coloured), reflecting little light. Then appear nila, a thin elastic crust of ice, undulating on waves and swell; pancake ice forming under severe conditions of waves from nila or grease pieces striking against one another, and finally the floes, thicker and larger pieces of ice.





Pancake formation from grease ice

As the temperature drops, the environment changes, we sight new birds and mammals, specific to this region of the world. The large family of birds nesting on the coast of the continent are Petrels: the Antarctic, snow, giants etc… They follow the ship whose propeller breaks the ice, releasing organisms that the birds feed on.



Snow petrels (in white) and Antarctic petrels, landing on the sea ice and catching krill

 Antarctic krill on the sea ice

However, the most important is now to sight penguins, making their way to the continent.

At this stage, even a penguin seems to go faster than a ship. The race is starting, hope we will make it before them !

Davis, 400 miles to go.

 
Lydie and Bianca - 24 October 2013 – 62°S-84°W

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