A new bed elevation model for the Weddell Sea sector of the West Antarctic Ice Sheet
A new bed elevation model for the Weddell Sea sector of the West Antarctic Ice Sheet
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DOI：
10.5194/essd-10-711-2018
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发表时间：
2017-10
影响因子：
11.4
通讯作者：
H. Jeofry;N. Ross;H. Corr;Jilu Li;M. Morlighem;P. Gogineni;M. Siegert
中科院分区：
文献类型：
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作者：
H. Jeofry;N. Ross;H. Corr;Jilu Li;M. Morlighem;P. Gogineni;M. Siegert
摘要。本文提出了一种新的数字高程模型（DEM），该模型具有1 km网格，用于南极西部冰盖（WAIS）威德尔海（WS）部分的床。DEM的总面积约为12.5万km 2，覆盖了研究所、Moller和基金会冰流，以及Bungenstock冰隆起。与Bedmap2产品相比，我们的DEM包含了新的航空地球物理数据集，这些数据集是由冰盖遥感中心（CReSIS）通过NASA冰桥行动（OIB）计划在2012年、2014年和2016年获得的。我们还改进了该地区现有最大数据集的床高程信息，该数据集是由英国南极调查局（BAS）极化雷达机载科学仪器（PASIN）在2010-2011年收集的，从Bedmap2中用于质量控制的相对粗糙的野外测量中确定的。虽然新DEM的总体形式与Bedmap2相似，但存在一些显着差异。例如，重新定义了冰盖内部和基础冰流接地线之间的深冰下槽（海平面以下~ 2公里）的位置和大小。从修改后的DEM中，我们能够更好地推导出基础水的预期路径，并且通过与使用Bedmap2计算的结果进行比较，我们能够评估水力流量对变化敏感的区域。考虑到该地区在接地线上可能受到海洋引起的融化的影响，特别是考虑到基础冰流槽的改进定义，我们修订的DEM将对冰盖建模有价值，有助于量化该地区未来的冰川变化，并由此对全球海平面产生潜在影响。可在https://doi.org/10.5281/zenodo.1035488上找到WS部门新的1公里床高程产品。
Abstract. We present a new digital elevation model (DEM) of the bed, with a 1 km gridding, of the Weddell Sea (WS) sector of the West Antarctic Ice Sheet (WAIS). The DEM has a total area of ∼ 125 000 km 2 covering the Institute, Moller and Foundation ice streams, as well as the Bungenstock ice rise. In comparison with the Bedmap2 product, our DEM includes new aerogeophysical datasets acquired by the Center for Remote Sensing of Ice Sheets (CReSIS) through the NASA Operation IceBridge (OIB) program in 2012, 2014 and 2016. We also improve bed elevation information from the single largest existing dataset in the region, collected by the British Antarctic Survey (BAS) Polarimetric radar Airborne Science Instrument (PASIN) in 2010–2011, from the relatively crude measurements determined in the field for quality control purposes used in Bedmap2. While the gross form of the new DEM is similar to Bedmap2, there are some notable differences. For example, the position and size of a deep subglacial trough ( ∼ 2 km below sea level) between the ice-sheet interior and the grounding line of the Foundation Ice Stream have been redefined. From the revised DEM, we are able to better derive the expected routing of basal water and, by comparison with that calculated using Bedmap2, we are able to assess regions where hydraulic flow is sensitive to change. Given the potential vulnerability of this sector to ocean-induced melting at the grounding line, especially in light of the improved definition of the Foundation Ice Stream trough, our revised DEM will be of value to ice-sheet modelling in efforts to quantify future glaciological changes in the region and, from this, the potential impact on global sea level. The new 1 km bed elevation product of the WS sector can be found at https://doi.org/10.5281/zenodo.1035488 .