Preliminary Results of the Inland Expeditions along a Transect from the Zhongshan Station to Dome A, East Antarctica
REN Jia wen, QIN Da he, XIAO Cun de (Laboratory of Ice Core and Cold Regions Environment, CAREERI, CAS, Lanzhou Gansu 730000, China)
Chinese National Antarctic Research Expedition (CHINARE) has made three inland traverses from the Zhongshan Station to Dome A in East Antarctica since 1996, and the farthest spot arrived ( 3 900 m a.s.l.) is 1 100 km away from the coast. During these traverses, glaciological investigation (including the ice sheet topography, stratigraphy in snow pits and snow/firn cores, snow accumulation, ice sheet thickness and ice flow velocity, etc.) has been carried out. In addition, snow samples were taken from snow pits (0 6~3 3 m in depth), and five ice cores (50~100 m in length) were recovered at four sites. The primary results show that the surveyed terrain is undulatory due to its adjacence to the Lambert Glacier and Mount Grove, and its facing towards the Lambert Glacier in the middle section of the traverse. Accumulation rate derived from stake measurement within the initial 460 km route is between 12 and 60 cm snow per year, equivalent to 46 to 210 kg·m -2 ·a -1 .The average density of 1 m surface snow is between 350 and 450 kg·m -3 . The depth of pore close off (corresponding to a density of 830 kg·m -3 ) is around 60 m at all the ice core drilling sites, which implies that snow metamorphose process is similar in the whole surveyed regions. Study of the 50 m ice core (300 km away from the Zhongshan Station) indicates that both accumulation rate and air temperature has a slight increase, which is consistent to the results deduced from most Antarctic sites, but converse to the situation at the west side of the Lambert Glacier.