西南极洲内部的冰流方向变化西南极洲内部的冰流方向变化
Martin J Siegert1, Brian Welch, David Morse
1Centre for Polar Observation and Modelling, Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol BS8 1SS, UK. m.j.siegert@bristol.ac.uk
概括
伯德站附近的一个独特的冰层折叠表明西南极洲过去的冰流变化. 这一发现表明,西南极洲中部可能比以前理解的更容易对未来的冰流变化产生影响.
科学领域:
- 冰川学的冰川学
- 地质物理学 地质物理学
- 南极研究南极研究
背景情况:
- 穿越冰的雷达揭示了西南极冰盖下方不寻常的折叠结构.
- 在这种折叠结构中,异常深处发现了同步的冰层.
研究的目的:
- 在伯德火车站附近的冰中研究形成独特的折叠结构.
- 在西南极洲重建过去的冰流动力学.
主要方法:
- 分析穿越冰的雷达数据.
- 解读冰层同位素和折叠轴方向的解释.
- 冰流动力学的建模.
主要成果:
- 确定了一个大型折叠结构 (>50公里长),其轴与当前的冰流方向倾斜45度.
- 折叠的形成很难用当今的冰流来解释.
- 大约1500年前与折叠轴平行的过去流动模式可以解释观察到的结构.
结论:
- 西南极洲冰流动力学的过去变化,可以从子冰结构中看出.
- 这些流量变化可能与靠近南极海岸的冰流变化有关.
- 西南极洲中部的冰层可能比以前认为的更容易对未来的变化做出反应,这将影响海平面上升的预测.
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