极地冰盖最近的质量平衡是从全球海平面变化模式中推断出来的
J X Mitrovica1, M E Tamisiea, J L Davis
1Department of Physics, University of Toronto, Canada. jxm@physics.utoronto.ca
Nature
|March 10, 2001
概括
全球海平面变化与气候变化有关. 新的建模揭示了融化冰盖造成的海平面不同模式,协调了过去的观测结果,并暗示了格陵兰岛.
科学领域:
- 气候科学 气候科学
- 冰川学的冰川学
- 海洋学 海洋学 海洋学
背景情况:
- 全球海平面是气候变化的关键指标,受到海洋热膨胀和冰川融化的影响.
- 对冰川静态同位素调整的潮数据的校正对于估计海平面上升至关重要.
- 以前的分析假设空间海平面上升模式将平均,忽视冰盖体积变化.
研究的目的:
- 为引力一致的海平面变化模式提供数值预测.
- 研究由极地冰盖 (南极和格陵兰) 和山地冰川的变化引起的海平面再分配.
- 通过使用预测模式,协调已发布的海平面记录中的空间变化.
主要方法:
- 海平面变化模式的数值建模.
- 纳入来自冰盖质量变化的引力效应.
- 对南极冰盖,格陵兰冰盖和山地冰川融化的海平面反应的分析.
主要成果:
- 在格陵兰岛和南极冰盖的变化预测了几何上明显的海平面变化模式.
- 这些预测模式与之前的海平面记录中观察到的空间变化相协调.
- 据估计,格陵兰冰在上个世纪的融化相当于海平面上升的0.6毫米/年,假设海洋热膨胀均.
结论:
- 极地冰盖体积的变化会产生非静态的海平面再分配.
- 引力一致的海平面预测为解释空间海平面记录提供了一个框架.
- 格陵兰冰盖在过去一个世纪对海平面上升的贡献通过这种建模方法来量化.
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