Filling in the Gap in Coastal Sea Ice Records with Community-Based Observations of Shore and Pack Ice Dynamics

Abstract:

Coastal sea ice plays a critical role in communities along Alaska’s Arctic Coast. Continued warming of the Earth’s climate is resulting in shorter ice seasons, limiting the time coastal ice can protect the shoreline and serve as a stable platform for travel. With no immediate solution to the climate crisis apparent, detailed observation of its effects on shorefast sea ice may be able to mitigate some of the impacts on coastal communities. Coastal ice dynamics have proven consistently difficult to measure, with the presence of land contaminating some remote sensing products and violent interactions between shorefast and pack ice. Shore-based observations from community members may be a solution to filling that gap, but are limited to distances that can be seen by the human eye.

This project analyzes shore-based radar data in Utqiagvik, AK as compared to community observations collected through the SIZOnet project. This shows that records of certain types of ice events are reliably indicative of ice conditions beyond the range of sight, while others are only locally relevant. Ridging events associated with shore-lead closing are good indicators of large areas of high-concentration pack ice beyond, whereas lead opening events can be associated with any type of ice condition beyond the near-shore area. These results suggest how community observations could be used to validate remote sensing products near coastlines.