Study Of Sea Ice And Snow Conditions In Prydz Bay And Surrounding Area During Austral Summer

As a kind of material which spread widely in the nature, sea ice play an important role in many fields. Owing to the high albedo and low thermal conductivity, sea ice can insulate the heat exchange between the ocean and atmosphere to some degree, and affect the climate; freeze and thaw processes of sea ice increase and dilute sea water salinity, respectively, this phenomenon can change salinity structure in a large scale. Antarctic is the cold source of the global atmosphere, as the main cold material in Antarctic, sea ice play a key part in global climate change. Knowing basic parameter of sea ice, such as thickness, ice concentration, ice extent and floe size, will help us to get a better understanding of the contribution of sea ice in climate.During the29th Chinese National Antarctic Research Expedition, the R.V. Xuelong entranced the Prydz Bay twice from late Nov,2012to the early Feb,2013. Three ship-based CCD camera method observations were conducted to obtain ice and snow thicknesses; two ship-based visual inspections were conducted as the ASPeCt program suggested; in addition, physical characteristic measurement were carried out in the fast ice zone off Zhongshan Station.The main work in this paper are as fellows. Firstly, sea ice/water surface temperature, air temperature and wind speed in the cruise tracks were measured, changing characteristics of these parameters with time has been explored. Secondly, vertical temperature, salinity and density of fast ice off Zhongshan Station were measured, ice temperature, salinity and density profile and their variations during the melting period were analysed. Thirdly, sea ice and snow thickness in the Prydz Bay were measured by ship-based CCD camera method, thickness spatial distributional characteristics in pack ice zone and fast ice zone have been evaluated; by comparing their different points, the cause of different features were revealed. Lastly, according to ASPeCt program, sea ice parameters such as thickness, ice concentration, ice extent and floe size were estimated by visual inspection, summer pack ice concentration and size spatial distributional characteristics as well as distribution characteristics of ice in different age were summarized, the cause of the special distribution were uncovered; by comparing the result from two observations, in combine with external environment factors from the Prydz Bay, the melt pattern of summer pack ice were presented.