Please use this identifier to cite or link to this item:
Title: Variability of nutrients and carbon dioxide in the Antarctic Intermediate Water between 1990 and 2014
Authors: Panassa, Essowe
Santana-Casiano, J. Magdalena 
González-Dávila, Melchor 
Hoppema, Mario
van Heuven, Steven M.A.C.
Völker, Christoph
Wolf-Gladrow, Dieter
Hauck, Judith
UNESCO Clasification: 251002 Oceanografía química
Keywords: Prime Meridian
Antarctic Intermediate Water
Decadal variability
Issue Date: 2018
Journal: Ocean Dynamics 
Abstract: Antarctic Intermediate Water (AAIW) formation constitutes an important mechanism for the export of macronutrients out of the Southern Ocean that fuels primary production in low latitudes. We used quality-controlled gridded data from five hydrographic cruises between 1990 and 2014 to examine decadal variability in nutrients and dissolved inorganic carbon (DIC) in the AAIW (neutral density range 27 < γn< 27.4) along the Prime Meridian. Significant positive trends were found in DIC (0.70 ± 0.4 μmol kg− 1year− 1) and nitrate (0.08 ± 0.06 μ mol kg− 1year− 1) along with decreasing trends in temperature (− 0.015 ± 0.01∘C year− 1) and salinity (− 0.003 ± 0.002 year− 1) in the AAIW. Accompanying this is an increase in apparent oxygen utilization (AOU, 0.16 ± 0.07 μ mol kg− 1year− 1). We estimated that 75% of the DIC change has an anthropogenic origin. The remainder of the trends support a scenario of a strengthening of the upper-ocean overturning circulation in the Atlantic sector of the Southern Ocean in response to the positive trend in the Southern Annular Mode. A decrease in net primary productivity (more nutrients unutilized) in the source waters of the AAIW could have contributed as well but cannot fully explain all observed changes.
ISSN: 1616-7341
DOI: 10.1007/s10236-018-1131-2
Source: Ocean Dynamics [ISSN 1616-7341], v. 68, p. 295-308
Appears in Collections:Artículos
Show full item record

Google ScholarTM




Export metadata

Items in accedaCRIS are protected by copyright, with all rights reserved, unless otherwise indicated.