Recent changes in the exchange of sea ice between the Arctic Ocean and the Canadian Arctic Archipelago

Abstract

[1] Sea ice is exchanged between the Arctic Ocean and Canadian Arctic Archipelago (CAA) but has not been quantified over long time periods. The corresponding mechanisms responsible for recent variability and change also remain unidentified. To address this, we estimated the sea ice area flux between the Arctic Ocean and the M'Clure Strait and Queen Elizabeth Islands (QEI) from 1997 to 2012 for the months of May to November. Over the period, there was a mean flux of −1 × 103 km2 (±21 × 103 km2) at the M'Clure Strait and mean flux of +8 × 103 km2 (±8 × 103 km2) at the QEI (positive and negative flux signs correspond to Arctic Ocean ice inflow and outflow, respectively). The M'Clure Strait had a mean flux of +5 × 103 km2 from May to September and a mean flux of −7 × 103 km2 from October to November. The QEI gates had a mean flux of +4 × 103 km2 from August to September with negligible ice exchange from May to July and October to November. More frequent high sea level pressure anomalies over the Beaufort Sea and Canadian Basin since 2007 have reduced Arctic Ocean multiyear ice (MYI) inflow into the M'Clure Strait. The presence of MYI in the CAA originating from the Arctic Ocean has been maintained by inflow at the QEI, which has increased since 2005. These recent increases in Arctic Ocean MYI inflow into the QEI can be attributed to increased open water area within the CAA that have provided more leeway for inflow to occur.