南大洋海底地形对冰山运动与搁浅的影响

发布时间：2017-12-26 16:38

本文关键词：南大洋海底地形对冰山运动与搁浅的影响　出处：《中国科学:地球科学》2017年04期 　论文类型：期刊论文

【摘要】：冰山是南极冰盖-冰架-海洋系统中活跃的组成部分,南大洋海底地形是影响冰山运动与搁浅的重要因素,但前人对此鲜有研究,本文结合南极Bedmap-2海底地形数据和杨百瀚大学冰山数据库所记录的冰山运动轨迹数据分析了海底地形对冰山运动和搁浅的影响.结果表明:(1)冰山搁浅事件与搁浅冰山轨迹点的数量分布主要与冰山水下厚度分布有关,在水深为200~300m海域内数量最高.自由运动冰山在南极陆坡锋区域(海洋水深500m左右)存在数量与速度的峰值;(2)海底地形对冰山运动的直接影响是冰山搁浅,在沿南极海岸线外围水深低于2000m的362×10~4km~2的海域里,从冰架前缘崩解的小型冰山可能搁浅区(水深小于400m)占28%即不易搁浅,这些搁浅区主要分布在东南极与南极半岛沿岸.从大冰架上崩解的大中型冰山(长轴大于18.5km)可能搁浅区(水深小于800m)占总面积的74%即较易搁浅;(3)在水深小于2000m的海域内冰山运动速度与海水深度之间具有正相关性(R=0.85,P0.01)(即海水越深的地方冰山运动越快),而海冰的季节性变化对这种相关性的影响不大,说明海底地形起伏所引起的海水深度的变化会对冰山运动速度产生影响.
[Abstract]:The iceberg is active part of the Antarctic ice - ice shelf ocean system in the Southern Ocean, seafloor topography is an important factor in the impact of movement of an iceberg and ran aground, but there are few studies, combining with the tip trajectory data recorded by the Antarctic Bedmap-2 terrain data and BYU iceberg database to analyze the influence of topography and grounding the movement of an iceberg. The results showed that: (1) the distribution of the thickness of iceberg stranding and grounding icebergs trace point quantity and depth of iceberg water, in the 200~300m area. The highest number of free movement of icebergs in the Antarctic region Lu Pofeng (ocean depth about 500m) peak in the presence of quantity and speed; (2) direct impact seabed topography on glacier iceberg is stranded in the periphery along the Antarctic coastline water depth is less than 362 of 2000m * 10~4km~2 waters from the ice shelf front collapse of small ice solution The mountain may be stranded area (water depth less than 400m) accounted for 28% of that is not easy to run aground, the stranded region mainly distributed in the southeast and along the coast of Antarctic Peninsula. From the ice shelf disintegration of large and medium sized iceberg (long axis is greater than 18.5km) may be stranded area (water depth less than 800m) accounted for 74% of the total area that is easily aground; (3) has a positive correlation between the speed of movement of an iceberg and sea water depth at a depth of less than 2000m area (R=0.85, P0.01) (i.e. the local movement of an iceberg in deeper water faster), and the seasonal variation of sea ice effect on this correlation is that changes in water depth of seabed terrain fluctuation caused by the impact of the iceberg the speed of movement.
【作者单位】：北京师范大学遥感科学国家重点实验室全球变化与地球系统科学研究院;全球变化与中国绿色发展协同创新中心;Department
【基金】：国家重点研发计划项目(编号:2016YFA0600103) 国家自然科学基金项目(批准号:41406211、41476161、41676182、41676176) 国家重点基础研究发展计划项目(编号:2012CB957704) 地理空间信息工程国家测绘地理信息局重点实验室经费资助项目(编号:201416) 高等学校博士学科点专项科研基金项目(编号:20120003110030) 国家海洋局极地考察办公室对外合作支持项目(编号:201611)资助
【分类号】：P736.1;P343.6
【正文快照】： 1.北京师范大学遥感科学国家重点实验室,全球变化与地球系统科学研究院,北京1 0 0 8 7 5;2.全球变化与中国绿色发展协同创新中心,北京1 0 0 8 7 5;3.D e p a r t m e n t o f A t m o s p h e r i c a n d E n v i r o n m e n t a l S c i e n c e s,U n i v e r s i t y a t

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