南极中山站附近海域固定冰的夏季变化

利用中国第21、22次南极科学考察(2004/2005、2005/2006)对中山站附近海域固定冰物理特性系统观测的结果,特别是依据其中2005年11月下旬至2006年1月下旬的现场实测数据详细分析了中山站附近海域固定冰消融过程物理性质的变化特征。结果表明:此区域固定冰从11月下旬开始消融,融冰期为62 d;同时,融冰期冰下水体温度迅速升高;在不断增强的太阳短波辐射和海洋热通量作用下,海冰温度也逐渐上升,并出现"相对冷中间层";热力和动力外强迫作用下,2005年12月18日-2006年1月14日期间此区域固定冰边缘线后退了20.9 km;另外,2005年12月18日固定冰边缘区走航冰厚监测结果还表明,边缘区海冰厚度在向岸方向有明显的增加趋势,并且随着接近海岸海冰厚度的离散程度逐渐减小。

SUMMER FAST-ICE EVOLUTION OFF ZHONGSHAN STATION,ANTARCTICA

Based on the field data acquired in the program of fast-ice observation off Zhongshan Station,Antarctica during the austral summer 2005/2006,physical properties evolution of fast-ice during the ice ablation duration has been analyzed in detail.Results show that the annual maximum ice thickness in 2005 occurred in later November,then started to melt,and the ablation duration was 62 days;sea water under the ice became warm in summer,so sea water temperature raised fleetly;corresponding to the warming of sea water and the strengthening of solar shortwave radiation,sea ice temperature raised gradually,and a "relative cold mid-layer" appeared in sea ice;under the thermodynamics and dynamics force,the fast-ice marginal line recoiled back to the shore fleetly,and the recoil distance was 20.9 km from December 18,2005 to January 14,2006.In addition,based on the data of sea ice thickness survey along the investigation route on December 18 of 2005,some ice thickness distribution characteristics in the marginal ice zone have been found: sea ice thickness increased from open water to fast ice zone distinctly;the diversity of floe ice thickness decreased from open water to fast ice zone gradually.