Work

The Yermak Pass Branch: A Major Pathway for the Atlantic Water North of Svalbard?

Year: 2017

Type: article

Abstract: An upward‐looking Acoustic Doppler Current Profiler deployed from July 2007 to September 2008 in the Yermak Pass, north of Svalbard, gathered velocity data from 570 m up to 90 m at a location covered by sea ice 10 months out of 12. Barotropic diurnal and semidiurnal tides are the dominant signals in the velocity (more than 70% of the velocity variance). In winter, baroclinic eddies at periods between 5 and 15 days and pulses of 1–2 month periodicity are observed in the Atlantic Water layer and are associated with a shoaling of the pycnocline. Mercator‐Ocean global operational model with daily and 1/12° spatial resolution is shown to have skills in representing low‐frequency velocity variations (>1 month) in the West Spitsbergen Current and in the Yermak Pass. Model outputs suggest that the Yermak Pass Branch has had a robust winter pattern over the last 10 years, carrying on average 31% of the Atlantic Water volume transport of the West Spitsbergen Current (36% in autumn/winter). However, those figures have to be considered with caution as the model neither simulates tides nor fully resolves eddies and ignores residual mean currents that could be significant.

Source: Journal of Geophysical Research Oceans

DOI: 10.1002/2017jc013271

Authors: Zoé Koenig, Christine Provost, Nathalie Sennéchael, Gilles Garric, Jean‐Claude Gascard