冰盖和固体地球对远方海平面历史的影响
Sophie E Bassett1, Glenn A Milne, Jerry X Mitrovica
1Department of Earth Sciences, University of Durham, Durham DH1 3LE, UK.
Science (New York, N.Y.)
|June 25, 2005
概括
在最后一个冰川时期的海平面变化模型中存在差异. 结合高粘度下层地幔和南极冰盖融水的新模型解决了这些问题,支持早期南极脱冰作为气候驱动因素.
科学领域:
- 地球科学 地球科学 地球科学
- 古气候学 古气候学
- 冰川学的冰川学
背景情况:
- 在最后一个冰川最大期之后,海平面变化的预测显示出差异.
- 在后冰期 (公元前14,0009,000年) 期间,塔希提,黄岛半岛和桑达大陆架的观测与以前的模型相冲突.
研究的目的:
- 解决后冰期海平面变化预测中的差异.
- 调查冰川静态调整和南极冰盖融水在海平面变化中的作用.
主要方法:
- 开发了一个冰川同静调整模型.
- 包括一个高粘度的下层地幔 (4 x 10^22 Pa s).
- 包括南极冰盖融化水脉冲IA (~15米欧斯塔特等价) 的显著贡献.
主要成果:
- 该模型成功地解决了预测和观察到的海平面变化之间的差异.
- 高低地幔粘度和大量的南极融水是关键因素.
- 这些发现与早期和快速南极脱冰的理论一致.
结论:
- 南极的早期和快速降冰起到了结束最后一个冰川时期的关键作用.
- 由地幔粘度和冰盖动态影响的冰川静态调整对于准确的海平面预测至关重要.
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