Seawater acidification and anthropogenic carbon distribution on the continental shelf and slope of the western South Atlantic Ocean

The Tropical Atlantic Observing System

“…Other main scientific questions are related to the roles of natural and anthropogenic processes that affect physical and biogeochemical changes on different timescales and their impact on marine ecosystems and biodiversity. In the context of climate change, ocean acidification is a key concern (Feely et al, 2004;de Carvalho-Borges et al, 2018). In many regions of the tropical Atlantic, the rate at which pH is declining, its causes, and its impacts on CaCO 3 shell-forming species are not well known.…”

The Effect of Agulhas Eddies on Absorption and Transport of Anthropogenic Carbon in the South Atlantic Ocean

“…To perform this analysis, we used the physical parameter measurement (θ, S) uncertainties together with the C T /A T estimation uncertainties, achieving values ranging from 2.82 to 3.83 µmol kg −1 for the application of 2011 and 2003 C T /A T precision, respectively. Compared with the precision of C T (1.39 and 1.66 µmol kg −1 for 2011 and 2003, respectively), these estimates allowed us to conclude that they are of the same order of magnitude and are also smaller than the previous reports from other C ant methods (e.g.,~5-6 µmol kg −1 for TrOCA [4,5,63] and 10 µmol kg −1 for ∆C* [64]).…”

“…Because we consider the C ant concentrations at a large latitudinal range (22 • S-35 • S), these values reflect the large hydrographic differences in temperature and salinity fields (as observed by comparing the panels of Figures 2 and 3). Additionally, the error propagation equations e.g., [4,5,53,63] was used to determine the precision of the C ant_TrOCA method. To perform this analysis, we used the physical parameter measurement (θ, S) uncertainties together with the C T /A T estimation uncertainties, achieving values ranging from 2.82 to 3.83 µmol kg −1 for the application of 2011 and 2003 C T /A T precision, respectively.…”

“…Recent studies noted that the central waters represented by the SACW in the South Atlantic Ocean are among the most affected by C ant penetration, leading to an acidification rate (i.e., change in seawater pH) of −0.0016 yr −1 and up to −0.0018 yr −1 for SACW since the preindustrial period [3][4][5]. These trends are higher than those already observed for the ocean layers immediately above and below the SACW, e.g., −0.0013 yr −1 for surface waters and −0.0010 yr −1 at the intermediate layer, for AAIW.…”

Global Changes, Anthropogenic Impacts and the Future of the Oceans

“…A comunidade científica brasileira é atuante neste tema através da Rede Brasileira de Pesquisa em Acidificação dos Oceanos (BrOA) 86 e vem abordando o tema no sentido de melhorar a qualidade dos dados observacionais com protocolos adotados internacionalmente, 85,87 através de experimentos com organismos para entender a resposta à acidificação [88][89][90][91] e estudos de observação na plataforma e áreas oceânicas (e.g. 92,93 ) especialmente no que diz respeito à porção oeste do Oceano Atlântico Equatorial e Sul.…”