格陵兰冰盖的速度结构的变化
Eric Rignot1, Pannir Kanagaratnam
1Jet Propulsion Laboratory, California Institute of Technology, Mail Stop 300-319, Pasadena, CA 91109-8099, USA. eric.rignot@jpl.nasa.gov
概括
格陵兰岛的冰川正在加速和增加冰的排放,大大导致全球海平面上升. 这一趋势正在向北扩大,这表明格陵兰岛未来的海平面贡献将会增加.
科学领域:
- 地球科学 地球科学 地球科学
- 冰川学的冰川学
- 气候科学 气候科学
背景情况:
- 格陵兰冰盖的动态对于了解全球海平面变化至关重要.
- 之前的研究表明区域性冰损失,但广泛的加速模式需要进一步调查.
研究的目的:
- 量化格陵兰岛冰川加速的程度和时间.
- 评估加速冰排放对格陵兰冰盖质量平衡的影响.
主要方法:
- 利用了跨越多年的卫星雷达干扰测量观测结果.
- 分析冰川速度变化以检测加速事件.
主要成果:
- 在1996年至2000年间,广泛的冰川加速被检测到在66°N以下,到2005年扩展到70°N.
- 在过去的十年中,加速的冰排放,特别是在格陵兰西部和东部,使冰盖质量赤字从90到220公里3/年翻了一番.
- 冰的流失速度正在增加.
结论:
- 持续向北的冰川加速表明,格陵兰岛对海平面上升的持续和不断增加的贡献.
- 由于广泛的动态冰损失,格陵兰冰盖的质量赤字正在恶化.
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