Collaborative Research: Physical Feedbacks in the Coastal Alaskan Arctic during Landfast Ice Freeze-up

北极海冰的减少增加了海岸线对海浪和风暴的暴露。秋天结冰的时间和地点也会影响沉积物在该地区的移动。这项提议的工作将探索阿拉斯加北极地区秋天的波浪、风暴和沉积物是如何相互作用的。这一新的认识将有助于更好地预测海岸线上的冰形成，因为海岸线在空间和时间上都有很大的变化。该项目将利用部署在海底和船只上的仪器所获得的观测数据，来观察阿拉斯加北极海岸部分地区的结冰情况。我们将引进成本更低、适应恶劣环境的北极测量新方法，并将其纳入今后的工作中。这些观测结果将与季节和以前的数据集进行比较，以了解不同年份的冻结如何变化。科学家们将与当地（北极地区）和美国大陆的中学生进行交流。这项工作将侧重于开发一个沿海海洋单元，向学生传授科学知识，并指导他们建造和部署小型仪器。北极沿海陆地冰的迅速减少增加了每年到达海岸的波浪暴露的持续时间和波浪能的强度。由于陆地固定冰形成于浅水，沉积物夹带到冰中也在调节输出中起关键作用。拟议的工作将解决阿拉斯加北极大陆架在秋季冻结期间物理过程的基本反馈和联系。这一新的认识将使我们能够更好地预测陆陆冰形成的季节和年代际变化，陆陆冰形成在多个时空尺度上具有很大的变异性。分析还将提高我们对暴雨期间沉积物路径的理解。现场实验将使用系泊、自主系统和海底电缆来捕捉阿拉斯加博弗特大陆架地区冻结过程的时空变化。该研究将采用嵌套方法，利用季节观测和已有的年际时间序列来捕捉近海强迫、当地水动力过程和海气交换的作用。测量将使用多种新型低成本遥测传感器、两栖无人机、海底电缆和北极硬化系泊的新型集成，为适应北极沿海的未来自主观测和监测系统建立能力。项目期间的推广工作将吸引当地的高中生，以及从未经历过北极的学生。我们将继续在“海岸海洋学”单元的基础上，在过去四年中为阿拉斯加北极村的高中生开发，扩展到中学，并将虚拟课程与每年的面对面活动结合起来，部署学生自制的小型仪器。此外，我们将与三个地点的中学科学班建立持续的接触，在实地考察之前进行亲自访问，在巡航期间进行直播活动，并在之后进行后续访问。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The loss of sea ice in the Arctic is increasing the exposure of the coastline to waves and storms. The timing and location of ice formation in the fall also affects how sediment moves through the region. The proposed work will explore how waves, storms, and sediment interact during fall in the Alaskan Arctic. This new understanding will result in better predictions of ice formation at the coastline, which varies significantly in space and time. The project will use observations obtained from instruments deployed on the seafloor and from ships to watch how freeze-up occurs over a section of the coastal Alaskan Arctic. We will introduce new ways of making measurements in the Arctic, that are both cheaper and better-adapted to the harsh environment, which can be incorporated into future work. These observations will be compared with seasonal and prior datasets to understand how the freeze-up may vary in different years. Scientists will engage with middle and high school students both locally (in the Arctic) and from the continental US. This work will focus on developing a coastal ocean unit, which teaches students about the science and walks them through building and deploying small instruments.The rapid decline in landfast ice in the coastal Arctic is increasing the duration of wave exposure and strength of wave energy reaching the coast each year. Because landfast ice forms in shallow water, sediment entrainment into the ice also plays a key role in mediating export. The proposed work will address fundamental feedbacks and connections of physical processes on the Alaskan Arctic shelf during fall freeze-up. This new understanding will enable better predictions of seasonal and decadal changes in landfast ice formation, which has a high amount of variability on multiple spatial and temporal scales. Analysis will also improve our understanding of the sediment pathways during the stormy fall period. The field experiment will use moorings, autonomous systems, and seafloor cables to capture the spatial and temporal variability in freeze-up processes over a region on the Alaskan Beaufort shelf. The research will take a nested approach, utilizing seasonal observations and pre-existing inter-annual time series to capture the roles of offshore forcing, local hydrodynamic processes, and air-sea exchange. Measurements will be made using novel integration of multiple new low-cost telemetered sensors, amphibious drones, seafloor cables, and Arctic-hardened moorings, building capacity for future autonomous observing and monitoring systems adapted for the coastal Arctic. Outreach efforts during the project will engage regional high school students, as well as students who have never experienced the Arctic. We will continue building on a “Coastal Oceanography” unit developed over the past four years for high schoolers in an Alaskan Arctic village, expanded to include the middle school, and incorporating virtual lessons with annual in-person activities to deploy small student-built instruments. Additionally, we will establish ongoing engagement with middle school science classes in three locations with in-person visits prior to the fieldwork, live-stream events during the cruise, and follow-up visits afterwards.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.