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Internal layering structure and subglacial conditions along a traverse line from Zhongshan Station to dome a,East Antarctica,revealed by ground-based radar sounding

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Applied Geophysics 2020年第5期17卷 870-878,905页

作者： Tang Xue-Yuan Sun Bo Wang Tian-Tian MNR Key Laboratory for Polar Science Polar Research Institute of ChinaShanghai 200136China

During the 21st Chinese National Antarctic Research Expedition(CHINARE 21,2004/05),a radar dataset was collected using a ground-based radar system,along a traverse line from Zhongshan Station to DT401(130 km from the Kunlun station).The internal layering structure and subglacial conditions were revealed along the radar profi *** internal layers,disturbed layers,and echo-free zones(EFZs)along the profi le were identifi ed and classifi ed,and the spatial distribution was *** on recent surface ice velocity data,we found that the internal layers at a depth of 200-300 m in the upper ice sheet are continuous,smooth,and nearly parallel to the ice surface *** addition,the thick band of continuous layers changes little with increasing *** depths below 300 m,the geometric structure of the internal layers and the vertical width of the EFZ band are infl uenced by the surface ice velocity and bed *** relatively high disturbance,layer discontinuity,and larger EFZ band width directly correspond to a higher surface ice velocity and a sharper bed *** particular,we found that at a depth of 650-950 km,the Lambert Glacier Rift in the Gamburtsev Mountains has a higher ice fl ow;moreover,the revealed internal layers are disturbed or broken,and the maximal vertical width of the EFZ band most likely exceeds 2000 m.

关键词： East Antarctic ice sheet dome a Radar Internal layers Subglacial conditions

Conceptual design studies of the 5 m terahertz antenna for dome a, Antarctica

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Research in Astronomy and Astrophysics 2013年第12期13卷 1493-1508页

作者： Ji Yang Ying-Xi Zuo Zheng Lou Jing-Quan Cheng Qi-Zhou Zhang Sheng-Cai Shi Jia-Sheng Huang Qi-Jun Yao Zhong Wang Purple Mountain Observatory Chinese Academy of Sciences Key Laboratory for Radio Astronomy Chinese Academy of Sciences Harvard-Smithsonian Center for Astrophysics

As the highest, coldest and driest place in Antarctica, dome a provides exceptionally good observing conditions for ground-based observations over terahertz wavebands. The 5 m dome a Terahertz Explorer （DATES） has been proposed to explore new terahertz windows, primarily over wavelengths between 350 and 200 pm. DATE5 will be an open-air, fully-steerable telescope that can function by unmanned operation with remote control. The telescope will be able to endure the harsh polar environment, including high altitude, very low temperature and very low air pressure. The unique specifications, including high accuracies for surface shape and pointing and fully automatic year-around remote operation, along with a stringent limit on the periods of on-site assembly, testing and maintenance, bring a number of challenges to the design, construction, assembly and operation of this telescope. This paper intro- duces general concepts related to the design of the DATE5 antenna. Beginning from an overview of the environmental and operational limitations, the design specifications and requirements of the DATE5 antenna are listed. From these, major aspects on the conceptual design studies, including the antenna optics, the backup structure, the pan- els, the subreflector, the mounting and the antenna base structure, are explained. Some critical issues of performance are justified through analyses that use computational fluid dynamics, thermal analysis and de-icing studies, and the proposed approaches for test operation and on-site assembly. Based on these studies, we conclude that the specifications of the DATE5 antenna can generally be met by using enhanced technological approaches.

关键词： dome a Antarctica -- antennas -- astronomy -- telescopes -- terahertz

Structure of the internal isochronous layers at dome a,East Antarctica

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Science China Earth Sciences 2011年第3期54卷 445-450页

作者： TANG XueYuan SUN Bo ZHANG ZhanHai ZHANG XiangPei CUI XiangBin LI Xin Ocean University of China College of Marine Environment Qingdao 266100 China SOA Key Laboratory for Polar Science Polar Research Institute of China Shanghai 200136 China

dome a (Kunlun Station) is considered a likely place for finding an ice core record reaching back to one million years. The internal isochronous layering of the Antarctic Ice Sheet, revealed by ice radar, is a prerequisite for selecting sites for deep ice core drilling that can be used for studying the paleoclimatic record. In 2004/2005, during the 21st Chinese National Antarctic Research Expedition (CHINARE 21), a 200-km long, continuous radar profile was obtained across dome a. The internal layers along the profile were derived from the stratigraphy detected by the radar. The morphology of the isochronous layers shows that: (1) The internal layers in the shallow ice sheet (0-500 m) are generally flat, with no more than 50 m of layer intervals, and have typical synclines and anticlines in some localized regions. (2) At 500-2000 m below the surface of the ice sheet, the layers appear as 'bright layers', and the width of the layer intervals expands to 50-100 m. (3) When the basal topographic wavelengths are approximate to the thickness of the ice (3 km), the traced internal layers, with localized bumps or concave folds, are asymptotic parallel to the subglacial topography. For the longer topographic wavelengths (~20 km) wider than the thickness of the ice, the layers do not rise and fall with the basal topography. The internal layers surrounding some mountain peaks representing the most extreme variation in the terrain are sharply disturbed by the subglacial topography. (4) Layer discontinuity and fracture were detected in the basal ice sheet. Finally, by combining this new information with that derived from existing data regarding ice thickness, we were able to select three potential sites for reconstructing the age-depth relationship of the ice core.

关键词： East Antarctic Ice Sheet dome a ice radar internal layers deep ice core

Elevation change around dome a region of Antarctica from EnviSat satellite radar altimetry during 2002–2012

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Geo-Spatial Information Science 2015年第4期18卷 193-199页

作者： Qiang QIANG Chunxia ZHOU Mingsheng LIAO Qiuyang ZHAO Zemin WANG Chinese Antarctic Center of Surveying and Mapping Wuhan UniversityWuhan 430079China Key Laboratory of Polar Surveying and Mapping National Administration of SurveyingMapping and GeoinformationWuhan UniversityWuhan 430079China State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhan 430079China

The expected responses of ice sheets to climate warming are growth in the thickness of the inland ice areas and thinning near the *** recent decades,researchers have identified glacier acceleration along Antarctic ice sheet coastal ***,the study of ice sheet interiors where seasonal accumulation eventually balances ice wastage at the lower elevation is poorly *** this paper,the ice sheet elevation change around dome a region is analyzed from 2002 to 2012 using two million elevation change measurements from EnviSat satellite radar altimeter data covering an area of about 7000 km2.A declining trend of 0.572±1.31 mm/year which means that the dome a region was in balance during the last decade can be *** addition,two obvious changes in accumulation which divide elevation change time series into three independent equilibration stages are also *** order to explain this phenomenon,two speculations related to snowfall and firn compaction are proposed in this paper.

关键词： elevation change satellite radar altimetry dome a Antarctica

Development and Applications of dome a-DEM in Antarctic Ice Sheet

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Chinese Geographical Science 2007年第2期17卷 160-165页

作者： LIU Jiying WEN Jiahong WANG Yafeng WANG Weili Beata M CATHSO Kenneth CJEZEK Department of Geography Shanghai Normal University Shanghai 200234 China SGT NASA Goddard Space Flight Center Code 614.1 Greenbelt MD 20771 USA Byrd Polar Research Center the Ohio State University Columbus OH43210 USA

dome a, the highest dome of East Antarctic Ice Sheet, is being an area focused by international Antarctic community after Chinese Antarctic Expedition finally reached there in 2005, and with the ongoing International Polar Year （IPY） during August 2007. In this paper two data processing methods are used together to generate two 100-m cell size digital elevation models （DEMs） of the dome a region （dome a-DEM） by using Cokriging method to interpolate the ICESat GLAS data, with Ihde-DEM as a constraint. It provides fundamental data to glaciological and geophysical investigation in this area. The dome a-DEM was applied to determining the ice-sheet surface elevations and coordinates of the south and north summits, defining boundaries of basins and ice ftowlines, deducing subglacial topography, and mapping surface slope and aspect in dome a region. The DEM shows there are two （north and south） summits in dome a region. The coordinate and the surface elevation of the highest point （the north summit） are 80°21＇29.86＂S, 77°21＇50.29＂E and 4092.71±1.43m, respectively. The ice thickness and sub-ice bedrock elevation at north summit are 2420m and 1672m, respectively. dome a region contains four drainage basins that meet together near the south summit. Ice ftowlines, slope and aspect in detail are also derived using the DEM.

关键词： dome a ICESat GLAS Cokriging DEM Antarctica

Dating a 109.9 m ice core from dome a (East Antarctica) with volcanic records and a firn densification model

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Science China Earth Sciences 2012年第8期55卷 1280-1288页

作者： LI ChuanJin XIAO CunDe HOU ShuGui REN JiaWen DING MingHu GUO Rui The State Key Laboratory of the Cryospheric Sciences Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of SciencesLanzhou 730000China School of Geographic and Oceanographic Sciences Nanjing UniversityNanjing 210093China Chinese Academy of Meteorological Sciences Beijing 100081China Alashan Desert Eco-Hydrology Experimental Research Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of SciencesLanzhou 730000China

A 109.9 m ice core was extracted at a location about 300 m away from the dome a summit （80°00′S, 77°21″E） by the Chinese team of the International Trans-Antarctic Science Expedition （ITASE） during the 21st Chinese National Antarctica Research Expedition （CHINARE） in January 2005. Two independent methods were used for dating the ice core, volcanic event markers shown by prominent non-sea-salt sulfate （nss-SO4^2-） and the Herron and Langway （H-L） firn densification model. Six promi- nent volcanic events （Agung 1963 AD, Tambora 1815 AD, Kuwae 1453 AD, Unknown 1259 AD, Taupo 186 AD and Pinatubo 1050 BC） were identified by comparison with other Antarctic ice cores. Based on the mean accumulation rates be- tween adjacent events, we estimate the age at the tim pore close-off depth （102 m） was 3516±100 a BP. This is the oldest close-off age ever reported from the Antarctic and the Greenland ice sheets. Calculations using the H-L model show that the age at the same depth is 3581±100 a BP. The two dating techniques differ by 65 years, or -1.8% of the record. We calculated the bottom age of the ice core as 4009±150 a BP using the volcanic dating method and 4115±150 a BP using the H-L model method.

关键词： Eastern Antarctic ice sheet dome a volcanic events ice core dating

基于Polar WRF的南极dome a极端低温事件分析

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冰川冻土 2020年第3期42卷 727-733页

作者：王一丞谢爱红丁明虎效存德中国科学院西北生态环境资源研究院冰冻圈科学国家重点实验室甘肃兰州730000 中国科学院大学北京100049 兰州中心气象台甘肃兰州730020 中国气象科学研究院北京100081 北京师范大学地表过程与资源生态国家重点实验室北京100875

南极作为地球的寒极,其最高点dome a地区于2013年8月1日气温达到-93.0℃的极低值。利用Polar Weather Research and Forecasting(Polar WRF)3.8.1模式,对发生在南极dome a地区的3次极端低温事件进行数值模拟分析。通过与自动气象站实测... 详细信息

南极作为地球的寒极,其最高点dome a地区于2013年8月1日气温达到-93.0℃的极低值。利用Polar Weather Research and Forecasting(Polar WRF)3.8.1模式,对发生在南极dome a地区的3次极端低温事件进行数值模拟分析。通过与自动气象站实测数据对比验证,模拟效果较为理想。结果表明:印度洋和大西洋交界区域的高压加强,其高压脊开始向南极内陆延伸,导致dome a地区气压升高,使得该地区天气晴好,云量极低,为极端低温事件发生奠定基础;同时,南极中心冷涡加强,长时间的冷平流和稳定的逆温层为dome a地区提供了足够的降温条件,并且加强了夜间辐射降温效应,稳定的垂直场、极低的向下长波辐射使得dome a地区的极端低温事件得以维持。

关键词：南极 dome a 极端低温 Polar WRF模式

Glittering prospects at dome a

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Science Bulletin 2017年第21期62卷 1432-1432页

作者： Jeremy Mould centre for astrophysical&supercomputing swinburne universityhawthorn 3122Australia

We are familiar with the idea that the elements from which we are made were created in stars, but where does gold come from, to pick on a heavier element？ Thanks to the optical detection of GW170817, reported here from the AST3-2 telescope [1], and at other southern telescopes, a day after its detection by LIGO, we are now closer to answering that question with a fascinating story of binary stellar evolution.

关键词： Glittering prospects dome a

Design and development of infrastructure of the dome a Kunlun Station(2005–2015)

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Advances in Polar Science 2017年第3期28卷 214-227页

作者： ZHANG Yi WANG Zhongjun Architectural Design and Research Institute of Tsinghua University Baosteel Construction System International Co.Ltd

To enable further advanced study of Antarctica, a new station called Kunlun Station has been built by China in the dome a region of the inland East Antarctic ice sheet. This paper describes the Antarctic station building design system that was developed with consideration of factors that may affect Kunlun Station, such as environment and climate, construction work and transport, environmental protection and energy conservation, psychological requirements and functional requirements. The design system included site selection, station planning, external building form, construction work, function and indoor environment, energy conservation, environmental protection, and material strategy. We also describe the experience acquired during the transportation and construction phases of Kunlun Station.

关键词： Antarctica Kunlun Station dome a architectural design strategy