RAPID: Recording Tsunami Impacts from the Taan Fjord, Alaska Landslide of October 17th, 2015

2015年10月17日，北美几十年来最大的山体滑坡发生在阿拉斯加冰湾东南部的塔恩峡湾。 山体滑坡引发了当地巨大的海啸。 卫星图像的流动指标表明，紧邻滑坡体的最大海啸上升超过190米。 这样的最大助跑将仅次于1958年Lituya湾滑坡所造成的，一个记录不佳（按现代标准）的事件，但它仍然是最重要的数据集，用于了解极端滑坡海啸灾害提供给工程界。该项目支持跨学科的，沿海的影响调查所产生的海啸的大安峡湾滑坡。 调查的目的是记录整个塔安峡湾和冰湾的海啸影响和爬高测量。 在减灾方面，海啸行为的记录至关重要，并将有助于解决许多问题，例如：基础设施需要离潜在的山体滑坡多远？液化天然气（LNG）设施离山体滑坡源有多远？加拿大西部和阿拉斯加正在提议的液化天然气（LNG）设施离山体滑坡源有多远？对现有码头、港口和港口的危害有多大？以及许多定期穿越峡湾系统的游轮。记录的数据对于正确说明滑坡源及其引发海啸的可能性至关重要。从初步模拟和早期勘测旅行来看，我们预计海啸会在海拔超过100米的广泛地区发生，但是当海啸穿过和离开塔安峡湾时，波高的衰减非常局部化。 由于上游和淹没距离极远，而且位置偏远，该小组将使用高精度的真实的实时动态测量系统，我们预计在对数据进行潮汐校正后，该系统将产生10厘米精度的位置高程。 需要收集的数据类型包括最重要的上升高度、水流深度剖面、沉积物冲刷和沉积区、瓦砾堆以及海啸对各类植被的影响。 本次调查的数据一经处理，将免费提供给工程界的所有成员。 特别是，Lynett参与了西部各州的海啸灾害测绘，他参与了国家海啸减灾计划（NTHMP），以及与其他研究滑坡海啸的人的现有合作表明，这些数据将立即被纳入正在进行的灾害研究。

On October 17th, 2015, the largest landslide in North America in decades occurred in Taan Fjord, an arm of southeast Alaska's Icy Bay. The landslide triggered an enormous local tsunami. Flow indicators from satellite imagery suggest that the maximum tsunami runup immediately adjacent to the slide mass exceeds 190 m. Such a maximum runup would be second only to that created by the 1958 Lituya Bay landslide, a poorly recorded (by modern standards) event that is nonetheless the most important dataset for understanding extreme landslide tsunami hazards available to the engineering community. This project supports an interdisciplinary, coastal impact investigation of the tsunami generated by the Taan Fjord landslide. The aim of survey is to record runup measurements and tsunami impacts throughout Taan Fjord and Icy Bay. In the context of hazard mitigation, a record of the tsunami behavior is of paramount importance, and would assist in resolving many questions, for example: How far away from potential landslides does infrastructure need to be located How close can liquefied natural gas (LNG) facilities, as are being proposed throughout western Canada and Alaska, be to landslide sources What about the hazard to existing marinas, harbors, and ports, and the many cruise ships that regularly travel through fjord systems The data to be recorded will be essential to the proper specification of the landslide source and its tsunamigenic potential.From preliminary simulations and early reconnaissance trips, we expect there to be widespread areas where the tsunami runup exceeds 100 meters in elevation, with a gradual, but very localized attenuation of wave height as the tsunami traveled through and out of Taan Fjord. Owing to the extreme runup and inundation distances, as well as the remote location, the team will use a high-accuracy Real Time Kinematic (RTK) survey system, which we expect will yield 10-cm accuracy location elevations, after the data is tide-corrected. The types of data to be collected include the most-important runup elevations, flow depth profiles, areas of sediment scour and deposition, debris piles, and the impact of the tsunami on various types of vegetation. The data from this survey, once processed, will be provided freely to all members of the engineering community. In particular, Lynett's involvement with tsunami hazard mapping in western States, his participation in the National Tsunami Hazard Mitigation Program (NTHMP), and existing collaborations with others studying landslide tsunamis indicates that this data will be folded into ongoing hazard studies immediately.