Increasing Multiyear Sea Ice Loss in the Beaufort Sea: A New Export
Pathway for the Diminishing Multiyear Ice Cover of the Arctic Ocean
Abstract
Historically multiyear sea ice (MYI) covered a majority of the Arctic
and circulated through the Beaufort Gyre for years. However, increased
ice melt in the Beaufort Sea during the early-2000s was proposed to have
severed this circulation. Constructing a regional MYI budget from
1997-2021 reveals that MYI import into the Beaufort Sea has increased
year-round, yet less MYI now survives through summer and is transported
onwards in the Gyre. Annual average MYI loss quadrupled over the study
period and increased from ~7% to ~33%
of annual Fram Strait MYI export, while the peak in 2018 (385,000
km^2) was similar to Fram Strait MYI export. An accelerating
ice-albedo feedback coupled with dynamic conditioning towards younger
thinner MYI is responsible for the increased MYI loss. MYI transport
through the Beaufort Gyre has not been severed, but it has been reduced
so severely to prevent it from being redistributed throughout the Arctic
Ocean