An Examination of the Wrangel Island Sea Ice Thickness Dipole

Abstract

The Beaufort Sea High is a high-pressure system located in the Beaufort Sea and influences ocean circulation in the western Arctic known as the Beaufort Gyre. Wrangel Island, located in the western Chukchi Sea, typically experiences easterly sea ice motion due to the Beaufort Gyre. We find that under these climatological conditions, moving ice is blocked by the island and piles up on its eastern side, while ice on its western side continues to drift. This results in an ice thickness dipole across the island. A reversal in the sense of the oceanic and atmospheric circulation across the western Arctic results in a dipole with the opposing sign. We find the dipole is present throughout the year and is strongest in January when the ice thickness difference is approximately 1m. During the spring, it is associated with the transient opening of a polynya to the west of the island. The dipole is the result of opposing ice divergence and convergence across the western Arctic and may impact ocean circulation and ecosystems within the Chukchi Sea.