Freeze-up and Break-up of Arctic Sea Ice in the U.S. Beaufort and Chukchi Seas (2025-2026)

The objective of this research is to collect, analyze, and maintain accurate, defensible data on annual freeze-up and break-up cycles of Arctic sea ice in the U.S. Beaufort and Chukchi Seas. This data will support scheduling of offshore activities to minimize infrastructure damage, inform spill response adequacy for worst-case discharges, and support cost-effective development aligned with Executive Order 14153 and Secretarial Order 3422.  Sea ice poses dynamic hazards to Arctic operations, including ice loads on structures, seafloor gouging, and constraints on vessel mobilization. As operations progress from exploration to production, reliable ice data becomes increasingly critical. Alaska Clean Seas uses this data to update its spill response tactics manual, cited in operator response plans, while BSEE's Alaska Regional Office uses it to evaluate Drilling Plans and vessel ice classification.  This study continues research begun in 2009, expanded in 2016–2017 to include break-up data, and further expanded in 2024–2025 to assess spill response plan adequacy and ice navigability for response vessels. The work spans BSEE's Emerging Technologies Branch and Research Response Branch, with findings shared with other federal agencies active in the Alaska OCS.  This abstract was drafted with the assistance of Claude, September 2026.