Seasonally derived components of the Canada Basin halocline

• Published in: Geophysical Research Letters
• Main Authors: Timmermans, Mary-Louise, Proshutinsky, Andrey, Marshall, John C, Scott, Jeffery R.
• Other Authors: Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences, Marshall, John
• Format: Article in Journal/Newspaper
• Language: English
• Published: American Geophysical Union (AGU) 2017
• Subjects: Arctic; Arctic Ocean; Chukchi Sea; Canada; canada basin; Chukchi; Sea ice
• Online Access: http://hdl.handle.net/1721.1/120078

The Arctic halocline stratification is an important barrier to the transport of deep ocean heat to the underside of sea ice. Surface water in the Chukchi Sea, warmed in summer by solar radiation, ventilates the Canada Basin halocline to create a warm layer below the mixed‐layer base. The year‐round persistence of this layer is shown to be consistent with the seasonal cycle of halocline ventilation. We present hydrographic observations and model results to show how Chukchi Sea density outcrops migrate seasonally as surface fluxes modify salinity and temperature. This migration is such that in winter, isopycnals bounding the warm halocline are blocked from ventilation, while the cool, relatively salty and deeper halocline layers are ventilated. In this way, the warm halocline is isolated by stratification (both vertically and laterally) each winter. Results shed light on the fate and impact to sea ice of the warm halocline under future freshening and warming of the surface Arctic Ocean. National Science Foundation (U.S.). Division of Polar Programs (Award 1350046) National Science Foundation (U.S.). Division of Polar Programs (Award 1603542)