Skip to Main content Skip to Navigation
Journal articles

Rapid acidification of mode and intermediate waters in the southwestern Atlantic Ocean

Abstract : Observations along the southwestern Atlantic WOCE A17 line made during the Dutch GEOTRACESNL programme (2010-2011) were compared with historical data from 1994 to quantify the changes in the anthropogenic component of the total pool of dissolved inorganic carbon (Delta C-ant). Application of the extended multilinear regression (eMLR) method shows that the Delta C-ant from 1994 to 2011 has largely remained confined to the upper 1000 dbar. The greatest changes occur in the upper 200 dbar in the Subantarctic Zone (SAZ), where a maximum increase of 37 mu mol kg(-1) is found. South Atlantic Central Water (SACW) experienced the highest rate of increase in C-ant, at 0.99 +/- 0.14 mu mol kg(-1) yr(-1), resulting in a maximum rate of decrease in pH of 0.0016 yr(-1). The highest rates of acidification relative to Delta C-ant, however, were found in Subantarctic Mode Water (SAMW) and Antarctic Intermediate Water (AAIW). The low buffering capacity of SAMW and AAIW combined with their relatively high rates of C-ant increase of 0.53 +/- 0.11 and 0.36 +/- 0.06 mu mol kg(-1) yr(-1), respectively, has lead to rapid acidification in the SAZ, and will continue to do so whilst simultaneously reducing the chemical buffering capacity of this significant CO2 sink.
Document type :
Journal articles
Complete list of metadata
Contributor : Gestionnaire HAL-UPMC Connect in order to contact the contributor
Submitted on : Wednesday, January 6, 2016 - 5:48:42 PM
Last modification on : Friday, January 21, 2022 - 3:28:22 AM
Long-term archiving on: : Thursday, April 7, 2016 - 4:13:56 PM


Publication funded by an institution


Distributed under a Creative Commons Attribution 4.0 International License



Lesley A. Salt, S. M. A. C. Van Heuven, M. E. Claus, E. M. Jones, H. J. W. De Baar. Rapid acidification of mode and intermediate waters in the southwestern Atlantic Ocean. Biogeosciences, European Geosciences Union, 2015, 12 (5), pp.1387-1401. ⟨10.5194/bg-12-1387-2015⟩. ⟨hal-01251672⟩



Record views


Files downloads