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

北极海冰的消失增加了海岸线在海浪和风暴中的风险。秋季结冰的时间和位置也影响着沉积物在该地区的移动方式。这项拟议的工作将探索在阿拉斯加北极秋季海浪、风暴和沉积物是如何相互作用的。这一新的认识将导致对海岸线结冰的更好预测，海岸线在空间和时间上存在显著差异。该项目将使用从部署在海底和船只上的仪器获得的观测数据来观察北极阿拉斯加沿海地区的一段冰冻是如何发生的。我们将推出在北极进行测量的新方法，这种方法既便宜，又能更好地适应恶劣环境，可以纳入未来的工作。这些观测数据将与季节性和先前的数据集进行比较，以了解不同年份的冻结情况可能会发生怎样的变化。科学家们将与当地(北极)和美国大陆的初中生和高中生进行交流。这项工作将集中于开发一个沿海海洋单元，该单元向学生传授科学知识，并引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波浪暴露的时间和每年到达海岸的波浪能量的强度。由于陆冰在浅水中形成，沉积物夹带到冰中也在调节出口方面发挥了关键作用。拟议的工作将解决阿拉斯加北极大陆架秋季冰冻期间物理过程的基本反馈和联系。这一新的理解将能够更好地预测陆冰形成的季节和年代变化，因为陆冰的形成在多个空间和时间尺度上具有很高的可变性。分析还将提高我们对暴风雨秋季期间沉积路径的理解。现场实验将使用系泊设备、自主系统和海底电缆来捕捉阿拉斯加博福特大陆架上一个地区冻结过程中的时空变化。这项研究将采取嵌套方法，利用季节观测和先前存在的年际时间序列来捕捉离岸强迫、局部水动力过程和海气交换的作用。将使用多种新的低成本遥测传感器、两栖无人机、海底电缆和北极加固系泊设备的新型集成进行测量，为适应北极沿海地区的未来自主观测和监测系统建设能力。该项目期间的外展工作将吸引地区高中生以及从未经历过北极的学生。我们将继续在过去四年为阿拉斯加北极一个村庄的高中生开发的“海岸海洋学”单元的基础上继续发展，扩大到包括中学，并将虚拟课程与年度面对面活动结合起来，部署学生建造的小型仪器。此外，我们将在三个地点建立与中学科学课程的持续互动，在实地考察之前进行面对面访问，在巡航期间进行现场直播活动，并在之后进行后续访问。该奖项反映了NSF的法定使命，并已通过使用基金会的智力优势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.