格陵兰冰盖:高海拔平衡和周边稀释
1Laboratory for Hydrospheric Processes, NASA Goddard Space Flight Center and EG&G Services, Wallops Flight Facility, Building N-159, Wallops Island, VA 23337, USA. Laboratory for Hydrospheric Processes, NASA Goddard Space Flight Center, Building 33, Room A225, Greenbelt, MD 20771, USA.
概括
格陵兰冰盖显示区域差异,但在2000米以上是平衡的. 较低的海拔,特别是在海岸附近,正在迅速稀薄,导致海平面上升.
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:
- 格陵兰冰盖的质量平衡对于理解全球海平面变化至关重要.
- 之前的研究已经提供了关于冰盖动态的数据,但需要进行全面的最新分析.
研究的目的:
- 用结合的高度测量数据分析格陵兰冰盖最近的质量平衡.
- 量化净冰损失及其对海平面上升的贡献.
主要方法:
- 将格陵兰岛北部 (1994年,1999年) 的飞机激光高度计调查数据与格陵兰岛南部的现有数据结合起来.
- 分析2000米以上和以下的海拔变化.
- 插入数据以估计年度净冰损失.
主要成果:
- 冰盖平均在2000米以上处于平衡状态,局部变厚和变薄.
- 显著的稀薄,每年超过1米,发生在海拔较低的海岸附近.
- 据估计,每年大约有51立方公里的冰损失.
结论:
- 格陵兰冰盖正在失去质量,主要是在较低的海拔地区.
- 这种冰损失对全球海平面上升作出了重大贡献,约占观察到的海平面上升的7%.
- 持续监测对于跟踪冰盖对气候变化的反应至关重要.
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