Spatial and temporal evolution of landfast ice near Zhongshan Station, East Antarctica, over an annual cycle in 2011/2012  

作　　者：Jiechen Zhao Qinghua Yang Bin Cheng Matti Lepp?ranta Fengming Hui Surui Xie Meng Chen Yining Yu Zhongxiang Tian Ming Li Lin Zhang 

机构地区：[1]College of Oceanic and Atmospheric Sciences, Ocean University of China [2]National Marine Environmental Forecasting Center [3]First Institute of Oceanography, Ministry of Natural Resources [4]Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, School of Atmospheric Sciences, Sun Yat-sen University [5]Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) [6]Finnish Meteorological Institute [7]Institute of Atmospheric and Earth Sciences, University of Helsinki [8]College of Global Change and Earth System Sciences (GCESS), Beijing Normal University [9]School of Geosciences, University of South Florida [10]Meteorological Service of Youyang Tujia and Miao Autonomous County [11]College of Global Change and Earth System Sciences , Beijing Normal University

出　　处：《Acta Oceanologica Sinica》2019年第5期51-61,共11页海洋学报（英文版）

基　　金：The National Natural Science Foundation of China under contract Nos 41876212,41406218 and 41676176;the Polar Strategy Project from Chinese Arctic and Antarctic Administration under contract No.20120317;the Opening Fund of Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions,CAS,under contract Nos LPCC2018001 and LPCC2018005

摘　　要：Annual observations of first-year ice(FYI) and second-year ice(SYI) near Zhongshan Station, East Antarctica,were conducted for the first time from December 2011 to December 2012. Melt ponds appeared from early December 2011. Landfast ice partly broke in late January, 2012 after a strong cyclone. Open water was refrozen to form new ice cover in mid-February, and then FYI and SYI co-existed in March with a growth rate of 0.8 cm/d for FYI and a melting rate of 2.7 cm/d for SYI. This difference was due to the oceanic heat flux and the thickness of ice,with weaker heat flux through thicker ice. From May onward, FYI and SYI showed a similar growth by 0.5 cm/d.Their maximum thickness reached 160.5 cm and 167.0 cm, respectively, in late October. Drillings showed variations of FYI thickness to be generally less than 1.0 cm, but variations were up to 33.0 cm for SYI in March,suggesting that the SYI bottom was particularly uneven. Snow distribution was strongly affected by wind and surface roughness, leading to large thickness differences in the different sites. Snow and ice thickness in Nella Fjord had a similar "east thicker, west thinner" spatial distribution. Easterly prevailing wind and local topography led to this snow pattern. Superimposed ice induced by snow cover melting in summer thickened multi-year ice,causing it to be thicker than the snow-free SYI. The estimated monthly oceanic heat flux was ～30.0 W/m2 in March–May, reducing to ～10.0 W/m2 during July–October, and increasing to ～15.0 W/m2 in November. The seasonal change and mean value of 15.6 W/m2 was similar to the findings of previous research. The results can be used to further our understanding of landfast ice for climate change study and Chinese Antarctic Expedition services.Annual observations of first-year ice(FYI) and second-year ice(SYI) near Zhongshan Station, East Antarctica,were conducted for the first time from December 2011 to December 2012. Melt ponds appeared from early December 2011. Landfast ice partly broke in late January, 2012 after a strong cyclone. Open water was refrozen to form new ice cover in mid-February, and then FYI and SYI co-existed in March with a growth rate of 0.8 cm/d for FYI and a melting rate of 2.7 cm/d for SYI. This difference was due to the oceanic heat flux and the thickness of ice,with weaker heat flux through thicker ice. From May onward, FYI and SYI showed a similar growth by 0.5 cm/d.Their maximum thickness reached 160.5 cm and 167.0 cm, respectively, in late October. Drillings showed variations of FYI thickness to be generally less than 1.0 cm, but variations were up to 33.0 cm for SYI in March,suggesting that the SYI bottom was particularly uneven. Snow distribution was strongly affected by wind and surface roughness, leading to large thickness differences in the different sites. Snow and ice thickness in Nella Fjord had a similar "east thicker, west thinner" spatial distribution. Easterly prevailing wind and local topography led to this snow pattern. Superimposed ice induced by snow cover melting in summer thickened multi-year ice,causing it to be thicker than the snow-free SYI. The estimated monthly oceanic heat flux was ～30.0 W/m2 in March–May, reducing to ～10.0 W/m2 during July–October, and increasing to ～15.0 W/m2 in November. The seasonal change and mean value of 15.6 W/m2 was similar to the findings of previous research. The results can be used to further our understanding of landfast ice for climate change study and Chinese Antarctic Expedition services.

关 键 词：landfast ice thickness OCEANIC heat flux PRYDZ BAY East ANTARCTICA 

分 类 号：P[天文地球]