ARCTIC SEA ICE 



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Ledyanoi zabereg (icy extension offshore). The new ice adhering 

 to the shore (in bays, gulfs, and among islands) when it begins 

 to grow outward toward the open sea. 



Fast-ice. Fully developed ledyanoi zabereg. It forms a more or 

 less wide belt of immovable new ice along the coasts — in 

 other words "sea ice while remaining fast in the position 



Fig. 16 — An old ice field in summer, with moutonnee surface and fresh-water pools in the de- 

 pressions. Siberian Sea. (Photograph from Russian Hydrographical Expedition to the Arctic.) 



of growth" (Priestley). The 12-fathom isobath is approxi- 

 mately the limit of the spread of the fast-ice into the open sea 

 in localities where the configuration of the coast exerts no 

 influence. 



Ice foot. The part of the fast-ice immediately close to shore that 

 is not affected by the rise and fall of the tide. 



Pack ice. Sea ice which has drifted from its original position. 



Icefield. An area of pack ice or Arctic Pack of such extent that its 

 limits cannot be seen from the ship's masthead. 



Ice floe. An area of pack ice or Arctic Pack from one-third of a 

 nautical mile in diameter to the size of an ice field. 



Glagon. A piece of pack ice or Arctic Pack ranging in size from 

 a cake about 2 to 3 feet in diameter to a floe. 



Hummock. The heaped-up products of the marginal crushing 

 and breaking up of the sea ice as a result of hummocking. 



