SGER: Channel incisions produced by tsunami waves along the coasts of Indonesia and Thailand

摘要该项目提出的首要假设是，海啸是否将水和沉积物的通量集中在少数几个选定的地点，从而产生类似潮汐通道的切口。尽管海啸波造成几乎均匀的涨潮，淹没了沿海的大片地区，但相应的水流很可能集中在少数几个选定的地区，造成局部侵蚀加剧。这一假设得到了申请人最近对潮汐环境中河道形态发展的研究的证实。浅水区的潮汐通量明显地将流量集中在几个切口内，从而产生冲刷和河道形成。拟议的研究是基于对印度尼西亚和泰国海岸线的高分辨率遥感图像的分析，这些图像受到最近2004年12月26日海啸的影响。该分析将揭示在海啸的涨潮和退潮阶段，洋流冲刷潮汐通道或更一般地说，冲刷切口的不同机制。最后，我们将使用一套用于潮间带环境地貌学研究的形态学工具来分析新河道的几何特征。拟议的研究具有很高的社会影响，因为我们可以深入了解海啸期间海水是如何进出沿海低地的。因此，我们可以从形态学的角度评估哪些地区更脆弱（即哪些地区受此类灾难性事件的影响最大），并对当地人口和经济产生明显影响。2004年12月26日印度尼西亚和泰国发生强烈海啸后，海滨重建工作正在进行中。因此，及时传播项目成果是至关重要的。我们的研究结果将为海啸救援和重建过程提供关键信息，指出哪些地区更容易受到侵蚀，并深入了解海啸波将致命能量集中在沿海地区的机制。此外，该项目可被视为海啸对沿海地区影响的更广泛调查的第一个组成部分，该调查将在不久的将来与泰国和印度尼西亚大学的研究人员合作开展。通过佛罗里达州立大学青年学者计划夏令营的研究生和高中生将参与该项目。

ABSTRACTThe overarching hypothesis addressed by the project is whether tsunami waves concentrate fluxes of water and sediments in few selected locations, producing incisions resembling to tidal channels. Despite the fact that tsunami waves cause an almost uniformrunup that floods large areas of the coastal landscape, the corresponding currents are most likely concentrated in few selected areas producing local enhanced erosion. This hypothesis is corroborated by recent studies by the applicant investigator on the morphological development of channels in tidal environments. Tidal fluxes in shallow areas clearly concentrate the discharge within few incisions thus producing scour and channel formation. The proposed research is based on the analysis of high-resolution remote sensing images of the coastline of Indonesia and Thailand impacted by the recent tsunami of December 26, 2004. The analysis will shed light on the different mechanisms by which currents scour tidal channels or, more generally, incisions, during the flood and ebb phase of a tsunami. We will finally analyze the geometric features of the new channels with a set of morphological tools developed for geomorphic studies in intertidal environments.Broader impact and motivation for exploratory research supportThe proposed research has a high societal impact, since we can gain insight into how the water is carried in and out coastal lowlands during a tsunami. We can thus assess what areas are more fragile from a morphological viewpoint (i.e. what areas are mostly affected by such a disastrous event) with a clear impact on local population and economy.After the powerful tsunami in Indonesia and Thailand of December 26 2004, the reconstruction of the waterfront is underway. It is then of crucial importance a timely dissemination of the project results. Our results will provide key information for both tsunami relief and rebuilding process, indicating what areas are more prone to erosion and giving insights on the mechanisms in which the tsunami wave concentrated its deadly energy along the coast. Furthermore this project can be seen as a first component of a broader investigation on the effects of tsunami waves on coastal areas, which will be developed in the near future in collaboration with researchers from universities inThailand and Indonesia. Both a graduate and a high school student through the FloridaState University Young Scholar Program Summer Camp will be involved in the project.