The loss of multiyear sea ice (MYI) in the Arctic Ocean is a significant; change that affects all facets of the Arctic environment. Using a; lagrangian ice age product we examine MYI loss and quantify the annual; MYI area budget from 1980-2021 as the balance of export, melt and; replenishment. Overall, MYI area declined at 72,500 km^2/yr, however; a majority of the loss occurred during two stepwise reductions that; interrupt an otherwise balanced budget and resulted in northward; contractions of the MYI pack. First, in 1989, a change in atmospheric; forcing led to a +56% anomaly in MYI export through Fram Strait. The; second occurred from 2006-2008 with anomalously high melt (+25%) and; export (+23%) coupled with low replenishment (-8%). In terms of; trends, melt has increased since 1989, particularly in the Beaufort Sea,; export has decreased since 2008 due to reduced MYI coverage north of; Fram Strait, and replenishment has increased over the full time series; due to a negative feedback that promotes seasonal ice survival at higher; latitudes exposed by MYI loss. However, retention to older MYI has; significantly declined, transitioning the MYI pack towards younger MYI; that is less resilient than previously anticipated and could soon elicit; another stepwise reduction. We speculate that future MYI loss will be; driven by increased melt and reduced replenishment, both of which are; enhanced with continued warming and will one day render the Arctic Ocean; free of MYI, a change that will coincide with a seasonally ice-free; Arctic Ocean.
