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

该项目解决的主要假设是，海啸波是否将水和沉积物的流动集中在少数选定的位置，产生类似潮汐水道的切口处。尽管海啸波造成了几乎一致的上升，淹没了大片沿海景观，但相应的洋流很可能集中在少数选定的地区，造成局部侵蚀加剧。这一假设得到了申请人调查者最近关于潮汐环境中航道形态发展的研究的证实。浅水地区的潮汐流量明显地将流量集中在几个切口处，从而产生冲刷和河道形成。这项拟议的研究是基于对印度尼西亚和泰国海岸线受2004年12月26日海啸影响的高分辨率遥感图像的分析。这一分析将阐明在海啸的洪水和退潮阶段，水流冲刷潮汐河道或更广泛地说，冲刷伤口的不同机制。最后，我们将用一套为潮间带环境地貌研究开发的形态工具来分析新航道的几何特征。广泛的影响和探索性研究的动机支持拟议的研究具有很高的社会影响，因为我们可以洞察海啸期间水是如何在沿海低地内外输送的。因此，我们可以从形态的角度评估哪些地区更脆弱(即哪些地区受到这种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，至关重要的是及时传播项目成果。我们的结果将为海啸救援和重建进程提供关键信息，指出哪些地区更容易受到侵蚀，并使人们对海啸波将致命能量集中在沿海地区的机制有深入的了解。此外，该项目可以被视为关于海啸波对沿海地区影响的更广泛调查的第一部分，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。通过弗罗里达特大学青年学者计划夏令营的一名毕业生和一名高中生都将参与该项目。

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.