Roles of ice-bands for the formation of seasonal ice zone

利用ECMWF数据和南极Syowa站MOS-1/1b MESSR图像，研究了冰带结构与大气条件之间的统计关系。在这些结果中，发现冰带结构与大气条件之间存在高度相关性。结果表明：(1)冰带的宽度和间距与日平均大气条件有关。(2)受日平均风场影响较大的带长轴向风向右70 ~ 90°；(3)在非冰风期，冰带的宽度和间距从内部到冰缘呈减小的趋势。从冬季到夏季，冰带的尺度不仅由于浮冰面积的减小而减小，而且由于风速的减小而减小。在南冰洋，海冰融化主要是由于海洋的变暖，在开阔的水域，更多的冰层是通过热量输入（主要是太阳辐射）融化的。我们提出了一个简化的冰-上海洋耦合模型，其中海冰仅由空气提供的海洋热量融化。模型显示，冰浓度与混合层温度的关系随时间渐近收敛（ct关系），这与25°~ 45°e区域夏季观测的ct图一致。模型显示，用于融化的热量与通过开放水域输入的热量之比倾向于作为冰浓度的函数来确定。在南极冰融化季节的典型情况下，比率大多在0.7到0.9之间。当模式扩展到经向二维时，加上风强迫，它近似地再现了南极海冰的经向退缩。该二维模型可以描述开放水反照率反馈效应，部分解释了南极海洋海冰退缩的年际变化。少

A statistical relationship between structures of ice bands and atmospheric conditions is examined by using ECMWF data and MOS-1/1b MESSR images received at Syowa Station, Antarctica. In these results, it is found that there are high correlation between structures of ice bands and atmospheric conditions. The results are summarized as follows :(1) It is suggested that the width and spacing of ice bands are correlated with atmospheric conditions averaged over several days.(2) Long axes of bands are oriented at 70-90° to the right of the wind direction that are influenced strongly by wind fields averaged over several days.(3) During period of off-ice winds, it is found that the width and spacing of ice bands tend to decrease from the interior region to the ice margin. It is suggested that the scales of ice bands decreases from winter to summer not only by decrease of ice floe size but also by decrease of wind speed.In the Antarctic Ocean, sea ice melts mostly by warming of the ocean mixed … More layer through heat input (mainly solar radiation) in open water area. We propose a simplified ice-upper ocean coupled model in which sea ice melts only by the ocean heat supplied from the air. The model shows that the relationship between ice concentration and mixed layer temperature converges asymptotically with time (CT-relationship), which agree with observation CT-plots during summer in the sector 25 ° -45 ° E. The model shows that the ratio of the heat used for melting to the heat input through open water is inclined to be determined as a function of ice concentration. For typical conditions in the Antarctic ice melt season, the ration ranges mostly between 0.7 and 0.9. When the model is extended to two-dimensions in the meridional direction, with the inclusion of wind forcing, it approximately reproduces the meridional retreat of the Antarctic sea ice. This two-dimensional model can describe the open water-albedo feedback effect, which partly explains the year-to-year variation of the sea ice retreat in the Antarctic Ocean. Less