南极洲乔治王岛长城湾一年生海冰的发育特征和物理性质

Developing and Physical Characteristics of First-year Sea Ice in Great Wall Bay and Its Adjacent Area by King George Island, Antarctica

The detailed evolution and the profile of ice thickness, pH value, salinity, the structure and fabric of the first-year sea ice in the Great Wall Bay and its adjacent area, by King George Island, are discribed. The period of sea ice cover is short, and its stability is low. The result of ice core shows that the sea ice consists mainly of snow ice in the Bay (over 70% of the thickness), and that the sea ice increases both upwards and downwards, characterized by the snow ice upwards and the congelation ice downwards. Snow ice contains interstitial water which refreezes and remelts alternatively during the seasons with weather changes. This pro- cess makes it difficult to calculate the ice thickness from the classical Stefan formula. There is a dentrites phenomenon with ice plates and brine lamellae both in congelation ice and the bottom of snow ice. In addition, the ice-axis alignment direction in congelation ice and snow ice is different from that in other regions. The ice fabric diagrame of the congelation ice is a weak small circle, and that of snow ice has a shape of central symmetry. Despite above-mentioned differences, the profiles of salimity of the ice cores are as same as that of other regions.