南极长城站附近地区冰川的温度状况

根据十多米深度钻孔温度的测量和分析,对长城站附近地区的冰川温度状况进行了讨论。近表面层温度在消融区稍低于-1℃,在积累区绝大部分区域接近或处于0℃。除海拔足够高的地方,如乔治王岛冰帽顶部,那里由于融化微弱且厚度不很大而致使冰与底床冻结在一起,该地区冰川大部分属于温型。

TEMPERATURE REGIME OF THE GLACIERS IN THE NEIGHBOURHOOD OF GREAT WALL STATION, ANTARCTICA

In the Southern Hemisphere summer of 1985-1986, several shallow boreholes (mostly 10 m and deeper) were drilled on the glaciers in Nelson Island and King George Island, which are near the Great Wall Station, Antarctica. Temperature measurement in them and analysis show that temperature at 10 m depth is a little lower than -1℃ in the abla tion area and close to or at 0C in the accumulation area except in the central part of King George Island Ice Gap, where elevation is about 680 m and temperature at 10 m is estima ted to be around -5℃. Based on the estimates of temperature distribution in the active layer or the near-surface layer, temperature regime of the deep layer is discussed qualitatively. The author concludes that temperature regime of the glaciers in this region is very different than that in the cold glaciers of the higher latitudes but it is not the same as in the temperate glaciers of the lower latitudes. The glaciers in this region are mostly temperate. However,if the altitude is higher such as in the central part of King George Island Ice Cap, the ice will become cold and is frozen to the bed because temperature in the active layer is lower due to decrease in air temperature and surface melting with increasing elevation, and ice thickness is not large.