Factors regulating the Great Calcite Belt in the Southern Ocean and its biogeochemical significance
Balch, William M.
Bates, Nicholas R.
Lam, Phoebe J.
Twining, Benjamin S.
Rosengard, Sarah Z.
Bowler, Bruce C.
Drapeau, David T.
Lubelczyk, Laura C.
MetadataShow full item record
KeywordCoccolithophores; Trace metals; Carbonate chemistry; Southern Ocean; Subantarctic Front; Subtropical Front
The Great Calcite Belt (GCB) is a region of elevated surface reflectance in the Southern Ocean (SO) covering ~16% of the global ocean and is thought to result from elevated, seasonal concentrations of coccolithophores. Here we describe field observations and experiments from two cruises that crossed the GCB in the Atlantic and Indian sectors of the SO. We confirm the presence of coccolithophores, their coccoliths, and associated optical scattering, located primarily in the region of the subtropical, Agulhas, and Subantarctic frontal regions. Coccolithophore-rich regions were typically associated with high-velocity frontal regions with higher seawater partial pressures of CO2 (pCO2) than the atmosphere, sufficient to reverse the direction of gas exchange to a CO2 source. There was no calcium carbonate (CaCO3) enhancement of particulate organic carbon (POC) export, but there were increased POC transfer efficiencies in high-flux particulate inorganic carbon regions. Contemporaneous observations are synthesized with results of trace-metal incubation experiments, 234Th-based flux estimates, and remotely sensed observations to generate a mandala that summarizes our understanding about the factors that regulate the location of the GCB.
© The Author(s), 2016. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Global Biogeochemical Cycles 30 (2016): 1124–1144, doi:10.1002/2016GB005414.
Suggested CitationGlobal Biogeochemical Cycles 30 (2016): 1124–1144
The following license files are associated with this item:
Except where otherwise noted, this item's license is described as Attribution-NonCommercial-NoDerivatives 4.0 International
Showing items related by title, author, creator and subject.
du Plessis, Marcel; Swart, Sebastiaan; Ansorge, Isabelle; Mahadevan, Amala; Thompson, Andrew F. (American Meteorological Society, 2019-04-11)Ocean stratification and the vertical extent of the mixed layer influence the rate at which the ocean and atmosphere exchange properties. This process has direct impacts for anthropogenic heat and carbon uptake in the ...
Katrein, Jody M. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2001-09)As part of Phase III of the U.S. GLOBEC Georges Bank program, drogued drifters and dye tracer were released into the pycnocline on the southern flank of Georges Bank to measure advective and diffusive transport relative ...
A model-dye comparison experiment in the tidal mixing front zone on the southern flank of Georges Bank Chen, Changsheng; Xu, Qichun; Houghton, Robert; Beardsley, Robert C. (American Geophysical Union, 2008-02-09)A process-oriented model-dye comparison experiment was conducted to examine the ability of a numerical ocean model to simulate the observed movement of dye across the tidal mixing front on the southern flank of Georges ...