OPP-PRF: Oceanographic Drivers of Nearshore and Landfast Sea Ice Seasonal Transitions

Landfast sea ice, which typically forms and breaks up every year along Arctic coasts, is an important link between the land and sea. People living in Alaskan Arctic coastal communities depend on landfast sea ice for hunting and travel. These communities report that landfast ice is becoming less stable and request better predictions about the seasonal evolution of landfast sea ice. This research will study how the ocean affects landfast sea ice, especially during the spring and autumn seasonal transitions. The investigator will measure ocean temperature, waves, and currents using buoys, ships, and instruments installed in the ice. These observations, which the investigator will share with the North Slope Borough Search and Rescue department, can be integrated with local knowledge to ensure travel and hunting activities are completed safely. The results of the study will improve ice forecasting, including better predictions of rapid ice breakup events. The investigator will involve an undergraduate student and local community members in this research. This research will study oceanographic processes driving nearshore and landfast ice evolution during the breakup and freeze-up seasons, evaluating the relative contributions of thermodynamic and dynamic processes. The first objective of this research is to understand the coupled evolution of the ocean wave field and nearshore ice at daily timescales and kilometer spatial scales. This project’s observations of the air-ice-ocean system will resolve the evolution of wave attenuation rates and the nearshore ice edge’s location in response to wave forcing. The investigator will use these data to study feedbacks between wind- and wave-driven ice drift, ice edge compactness, and wave attenuation in the diverse ice types of the nearshore ice pack. The results from this part of the study will adapt parameterizations developed for the offshore marginal ice zone to the nearshore environment. The second objective of this research is to understand how the ocean contributes to landfast ice breakup via currents, waves, or sea level changes. Using concurrent observations of the atmosphere, ice, and ocean, this study will identify oceanographic variables that destabilize the landfast ice and precondition breakup. The results from this part of the study will connect local ice dynamics to readily available (larger scale) weather and ocean predictions. 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.