Morphological recovery of beach severely damaged by the 2011 great east Japan tsunami
Morphological recovery of beach severely damaged by the 2011 great east Japan tsunami
复制标题
2011 年东日本海啸严重受损海滩的形态恢复
DOI：
10.1016/j.ecss.2019.106274
复制
发表时间：
2019
期刊：
影响因子：
--
通讯作者：
Y. Mitobe
中科院分区：
文献类型：
--
作者：
V. Hoang;Hitoshi Tanaka;Y. Mitobe
2011年3月11日发生的东日本大海啸（2011年海啸）对日本宫城县仙台沿岸的海岸和河口形态造成了重大变化。利用航空照片、测深数据和经验正交函数（EOF）方法对海啸发生后的恢复过程进行了调查。航拍分析结果表明，海啸前（第1期）岸线处于动态平衡状态。在事件发生后的两年（第二阶段），海岸线的恢复非常快。然而，在接下来的4.5年（第3期）期间，它更加稳定。对水深资料的分析表明，除了邻近海岸的泥沙供应外，近海海床的侵蚀泥沙被输送到岸上，导致泻湖地区的海岸线大量恢复。仙台海岸的沿岸系统在海啸前后以及第二和第三时期之间也发生了显著变化。沉积在内陆和泻湖地区的沉积物被认为是海啸后海岸线向内后退约70 m - 80 m的主要原因。对于EOF分析，可以解释海啸后两个海岸线数据集的EOF分析中前三个主导分量所反映的海岸过程。在第2阶段，严重受损地区（泻湖）的形态恢复是最主要的过程，而第2阶段是海岸线的跨岸变化，是海啸前最主要的过程。第二阶段第一和第二部分的贡献率相差约4倍。在接下来的4.5年（第3期）期间，由高波引起的海岸线的跨岸变化再次成为最主要的过程，而第二个分量反映了海岸沉积物的输运。这两个主要成分与海啸前的成分相似。前两个分量在海啸前后的贡献率也比较接近。这证实了沿海过程已经恢复到海啸前的状态。这是从这项研究中推断出来的一个重要发现，因为像2011年海啸这样的强海啸可能是一个主要的扰动，将“正常的”跨岸、长岸水界面的变化推向一个不同的状态。
The Great East Japan tsunami, which occurred on 11 March 2011 (the 2011 tsunami), caused significant changes to the coastal and estuarine morphology along the Sendai coast, Miyagi prefecture, Japan. The recovery process, which took place subsequently after the tsunami, is investigated using aerial photographs, bathymetry data, and Empirical Orthogonal Function (EOF) method. Results from the aerial photograph analysis indicate that the shoreline was in the dynamic equilibrium condition in the period before the tsunami (Period 1). The recovery of the shoreline was very fast in the period of two years post event (Period 2). However, it was more stable for the period of the next 4.5 years (Period 3). The analysis on the bathymetry data indicates that, besides the sediment supply from adjacent coasts, eroded sediment of the offshore seabed was transported onshore and led to a mass recovery of the shoreline at the lagoon areas. The littoral system of the Sendai coast also changed significantly between the periods before and after the tsunami, as well as between Periods 2 and 3. The sediment deposited inland and in the lagoon areas is perceived as the main reason that caused the retreat inwardly of about 70 m–80 m of the shoreline after the tsunami. Regarding the EOF analysis, the reflected coastal processes of the first three dominant components from the EOF analysis for two shoreline data sets after the tsunami can be explained. In Period 2, the morphological recovery at severely damaged areas (lagoons) was the most dominant process, whilst the second one was the cross-shore variety of shoreline which was the most dominant process preceding tsunami. The contribution rate of the first and second components in Period 2 is about 4 times different. In the period of the next 4.5 years (Period 3), the cross-shore variety of shoreline which was induced by high waves came back to be the most dominant process, whilst the second component reflects the longshore sediment transport. These two dominant components are similar to the ones before the tsunami. The contribution rates of the first two components before and after the tsunami are relatively close as well. That confirms that the coastal processes have returned back to the conditions before the tsunami. This is an important finding which is deduced from this study because a strong tsunami such as the 2011 tsunami could have been a major disturbance, tipping the “normal” cross-, long-shore variability of shoreface water interface towards a different regime.
影响因子：
5.2
作者：
Mori, Nobuhito;Takahashi, Tomoyuki;Yanagisawa, Hideaki
通讯作者：
Yanagisawa, Hideaki
2011年东北冲海啸仙台湾沿岸沉积物的空间厚度变化
影响因子：
2.9
作者：
Goto;K.;Hashimoto;K.;Sugawara D.;Yanagisawa;H.;Abe;T.
通讯作者：
T.
DOI：
--
发表时间：
2004
期刊：
Proceedings of the 4^<th> Congress of Environmental Hydraulics and the 14^<th> Congress of APD-IAHR
影响因子：
--
作者：
Kang;H.W.;Tanaka;H.
通讯作者：
H.