Open AccessWinter Convection Transports Atlantic Water Heat to the Surface Layer in the Eastern Arctic Ocean*
Author(s) -
Igor V. Polyakov,
Andrey V. Pnyushkov,
Robert Rember,
Laurie Padman,
Eddy C. Carmack,
Jennifer M. Jackson
Publication year - 2013
Publication title -
journal of physical oceanography
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.706
H-Index - 143
eISSN - 1520-0485
pISSN - 0022-3670
DOI - 10.1175/jpo-d-12-0169.1
Subject(s) - pycnocline , halocline , mixed layer , geology , oceanography , climatology , heat flux , sea ice , arctic ice pack , atmospheric sciences , environmental science , salinity , heat transfer , physics , thermodynamics
A 1-yr (2009/10) record of temperature and salinity profiles from Ice-Tethered Profiler (ITP) buoys in the Eurasian Basin (EB) of the Arctic Ocean is used to quantify the flux of heat from the upper pycnocline to the surface mixed layer. The upper pycnocline in the central EB is fed by the upward flux of heat from the intermediate-depth (~150–900 m) Atlantic Water (AW) layer; this flux is estimated to be ~1 W m−2 averaged over one year. Release of heat from the upper pycnocline, through the cold halocline layer to the surface mixed layer is, however, seasonally intensified, occurring more strongly in winter. This seasonal heat loss averages ~3–4 W m−2 between January and April, reducing the rate of winter sea ice formation. This study hypothesizes that the winter heat loss is driven by mixing caused by a combination of brine-driven convection associated with sea ice formation and larger vertical velocity shear below the base of the surface mixed layer (SML), enhanced by atmospheric storms and the seasonal reduction in density difference between the SML and underlying pycnocline.