从格陵兰出口冰川的冰排放的快速变化
Ian M Howat1, Ian Joughin, Ted A Scambos
1Polar Science Center, Applied Physics Lab, University of Washington, 1013 Northeast 40th Street, Seattle, WA 98105-6698, USA. ihowat@apl.washington.edu
概括
格陵兰岛 - 格陵兰岛
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:
- 格陵兰的出口冰川是全球海平面上升的重要贡献者.
- 了解冰流的短期变化对于准确的气候模型至关重要.
研究的目的:
- 分析了格陵兰岛两个主要出口冰川最近的冰排放和质量损失动态.
- 调查冰川质量平衡短期波动的原因.
主要方法:
- 利用卫星衍生的地表高度和速度数据.
- 分析了冰流和冰川几何学的时间变化.
主要成果:
- 在不到一年的时间内 (2004年) 观察到综合质量损失率翻倍.
- 到2006年,质量损失率恢复到以前的水平,这归因于分娩前端重新平衡.
- 总质量损失是引力衍生的估计的一小部分,这表明了其他损失机制.
结论:
- 短期内,冰川几何结构的快速重新平衡显著影响了质量损失.
- 对出口冰川动态的高分辨率监测对于完善海平面上升预测至关重要.
- 与引力衍生估计的差异凸显了对综合观测方法的需求.
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