在格陵兰岛和南极冰盖边缘进行了广泛的动态稀释
Hamish D Pritchard1, Robert J Arthern, David G Vaughan
1British Antarctic Survey, Natural Environment Research Council, Madingley Road, Cambridge CB3 0ET, UK. hprit@bas.ac.uk
Nature
|September 25, 2009
概括
格陵兰岛和南极洲冰川的动态变薄正在加速海平面上升. 高分辨率的卫星数据显示,大范围的冰川变化是由冰盖边缘的海洋融化推动的.
科学领域:
- 冰川学的冰川学
- 气候科学 气候科学
- 地球观测 地球观测
背景情况:
- 格陵兰岛和南极洲的冰川正在加速,导致全球海平面上升.
- 动态稀释,或加速的冰流,是不了解和不可预测的.
- 以前的卫星传感器无法解决快速流动的沿海冰川的变化.
研究的目的:
- 用高分辨率卫星高度测量绘制格陵兰岛和南极冰盖接地边缘的海拔变化图.
- 通过将观察到的高度变化与表面质量平衡波动进行比较,将动态稀释信号分离出来.
- 了解两个冰盖之间动态稀释的程度和强度.
主要方法:
- 使用高分辨率的冰,云和陆地海拔卫星 (ICESat) 激光高度测量数据.
- 在格陵兰岛和南极冰盖的整个接地边缘绘制海拔变化.
- 将快速和缓慢流动的冰的高度变化速度与预期的表面质量平衡变化进行比较.
主要成果:
- 在格陵兰的所有度观察到动态稀释,并在南极接地线上加剧.
- 冰川的稀释持续了几十年,冰架崩塌后,并深入内陆.
- 快速流动的格陵兰冰川 (>100 m yr−1) 平均稀薄0.84 m yr−1;南极冰川在阿蒙森海海域的稀薄超过9.0 m yr−1.1.
结论:
- 由海洋驱动的冰架融化驱动的动态稀释是冰盖深刻变化的主要驱动因素.
- 海洋边缘的冰川动态是预测未来海平面上升的关键因素.
- 高分辨率的卫星高度测量对于监测这些动态的冰盖过程至关重要.
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