Tidal evolution of the northwest European shelf seas from the Last Glacial Maximum to the present
Tidal evolution of the northwest European shelf seas from the Last Glacial Maximum to the present
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末次盛冰期至今欧洲西北部陆架海的潮汐演化
DOI：
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发表时间：
2006
期刊：
影响因子：
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通讯作者：
A. Purcell
中科院分区：
文献类型：
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作者：
Katsuto Uehara;J. Scourse;K. Horsburgh;K. Lambeck;A. Purcell
[1]二维古潮汐模拟已经进行了调查潮汐和潮汐相关的变化（潮汐振幅，潮流速度，季节分层，峰值床应力矢量）发生在西北欧洲陆架海在过去的20万年。模拟测试的影响，货架范围内的均衡变化的海平面，将两个不同的地壳反弹模型的结果，并通过设置开放的边界值固定到目前的状态或变量根据全球古潮汐模型的结果的海洋潮汐变化的影响。使用不同的地壳反弹模型并不影响潮汐模式的总体变化，但变化的时间是敏感的局部均衡的影响，不同的模型之间。海洋潮汐变化的纳入大大增加了10 ka BP前凯尔特海和马林海的潮汐和潮流的振幅，并对陆架海的季节分层条件的分布，峰值床应力矢量和潮汐耗散的大小有很大的影响。季节性分层的预测支持在凯尔特海的潮汐混合前迁移的证据。使用全球模式进行的其他实验表明，近海潮汐的变化主要是由海平面和冰盖范围的变化引起的。特别是，在10-8 ka BP观察到的大幅度减少是由于哈德逊海峡的开放伴随着劳伦提斯冰盖的退缩。
[1] Two-dimensional paleotidal simulations have been undertaken to investigate tidal and tide-dependent changes (tidal amplitudes, tidal current velocities, seasonal stratification, peak bed stress vectors) that have occurred in the NW European shelf seas during the last 20 ka. The simulations test the effect of shelf-wide isostatic changes of sea level by incorporating results from two different crustal rebound models, and the effect of the ocean-tide variability by setting open boundary values either fixed to the present state or variable according to the results of a global paleotidal model. The use of the different crustal rebound models does not affect the overall changes in tidal patterns, but the timing of the changes is sensitive to the local isostatic effects that differ between the models. The incorporation of ocean-tide changes greatly augments the amplitude of tides and tidal currents in the Celtic and Malin seas before 10 ka BP, and has a large impact on the distribution of seasonally stratified conditions, magnitude of peak bed stress vectors and tidal dissipation in the shelf seas. The predictions on seasonal stratification are supported by well-dated evidence on tidal mixing front migration in the Celtic Sea. Additional experiments using the global model suggest that the variability of offshore tides has been caused mainly by changes of eustatic sea level and ice-sheet extent. In particular, a large decrease observed at 10–8 ka BP is attributed to the opening of Hudson Strait accompanied by the retreat of the Laurentide Ice Sheet.