Accelerating Ice Mass Loss Across Arctic Russia in Response to Atmospheric Warming, Sea Ice Decline, and Atlantification of the Eurasian Arctic Shelf Seas

Glaciers and ice caps of the Russian Arctic are currently experiencing accelerating mass loss as a result of strong atmospheric and oceanic warming in the Barents and Kara Sea (BKS) region. Since 2010, this loss has been driven by both increased surface ablation, and dramatic shifts in ice dynamics at individual drainage basins across the entire Eurasian High Arctic. Here, we provide a high-resolution spatial and temporal overview of ice surface elevation change and mass imbalance across both Novaya Zemlya and Severnaya Zemlya using CryoSat-2 interferometric swath altimetry from 2010 to 2018. We find a total mass imbalance of -300 kg m(-2) a(-1), marked by a strong east-to-west gradient, with higher rates of loss over Novaya Zemlya (9.7 +/- 0.5 Gt a(-1) at 431 +/- 22 kg m(-2) a(-1)) in the west compared to Severnaya Zemlya (1.7 +/- 0.1 Gt a(-1) at 97 +/- 8 kg m(-2) a(-1)) in the east. Correlation between time series of surface elevation change and climate forcing reveals a quasi-linear relationship between coupled ocean-atmospheric forcing and glacier change over Novaya Zemlya, in agreement with similar findings from east Greenland. We further discern the likely role of ocean warming as the key factor driving dynamic ice loss in Severnaya Zemlya, owing to increasingly warm Atlantic Waters circulating along the Eurasian continental margin. We conclude that simple, linear relationships between environmental forcing and glacier change may be sufficiently accurate to parametrize ice loss in regions where synchronous, coupled ocean-atmosphere forcing prevails.