*corresponding author

• Main Authors: David A. Sutherl, Fiammetta Straneo B, Steven J. Lentz B, Woods Hole, Woods Hole Ma
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Hudson Strait; Hudson Bay; Labrador Current; freshwater; Hudson; Labrador Shelf; Davis Strait; Fram Strait; Labrador Sea; North Atlantic
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.370.4101; http://www.whoi.edu/science/PO/people/fstraneo/pdfs/Sutherland_HS_2009.pdf

The waters that flow out through Hudson Strait, a coastal system that connects Hudson Bay with the Labrador Sea, constitute the third largest freshwater contribution to the northern North Atlantic, behind only Fram Strait and Davis Strait. Recent studies have documented the mean structure and transport of the outflow, as well as highlighting significant variability on synoptic (days to a week) scales. This study examines the variability of the outflow on these synoptic scales through the use of an unprecedented set of observations collected by a mooring array from 2005-2006 in the strait. In particular, we focus on the mechanisms that cause the freshwater export to be concentrated in a series of discrete pulses during the fall/winter season. We show that these freshwater pulses, which occur once every 4.4 days on average, are anticyclonic, surface-trapped eddies propagating through the strait and carried by the mean outflow. Their occurrence is related to the passage of storms across Hudson Bay, although local instability processes could also play a role in their formation. The eddies are responsible for approximately 40 % of the mean volume transport and 50 % of the mean freshwater transport out of the strait. We discuss the implications of this new freshwater release mechanism on the delivery of nutrient-rich and highly stratified waters to the Labrador shelf, a highly productive region south of Hudson Strait. 18