格陵兰冰盖因融化而加快的速度,被高效的冰下排水所抵消
Aud Venke Sundal1, Andrew Shepherd, Peter Nienow
1School of Earth and Environment, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK.
Nature
|January 29, 2011
概括
表面融化影响格陵兰岛的冰盖流动. 温暖的年份显示夏季冰流较慢,这是由于高效的排水,而不仅仅是基底滑,影响了气候变化模型.
科学领域:
- 冰川学的冰川学
- 气候科学 气候科学
- 地球系统科学 地球系统科学
背景情况:
- 表面融化影响冰川和冰盖的动态.
- 在气候变暖下,融化加剧对格陵兰冰盖流动的影响是不确定的,之前的研究结果是矛盾的.
研究的目的:
- 为了研究格陵兰冰盖的陆地终端部门的冰流如何在几年内变化,表面融化变化.
- 了解融化水流动和冰的速度之间的关系,特别是在更温暖的年份.
主要方法:
- 利用卫星观测格陵兰西南部的冰运动.
- 分析了多年来冰流的流动模式,其中融化条件显著不同.
- 开发并应用了结合排水系统动态的冰盖流量模型.
主要成果:
- 峰值冰的加速度与融化强度相关,但夏季平均流量并非如此.
- 冰川的减速发生在每日流量超过大约1.4厘米时,特别是在温暖的年份.
- 较温暖的年份与较冷的年份相比,夏末加速度减少,快速流动周期较短,夏季冰流总体较慢.
结论:
- 在温暖的年份,格陵兰的冰流行为受到高效的冰下排水的影响,类似于山地冰川,而不是仅仅是基底滑.
- 冰下排水的动态演变,包括空洞和通道流动之间的过渡,对于准确地建模冰盖对气候变暖的反应至关重要.
- 未来对格陵兰冰盖在气候变化下的流动进行模拟,必须将这些排水动态纳入可靠的预测中.
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