Anthropogenic Carbon Transport Variability in the Atlantic Ocean Over Three Decades

• Published in: Global Biogeochemical Cycles
• Main Authors: Caínzos, Verónica, Velo, A., Pérez, Fiz F., Hernández Guerra, Alonso
• Other Authors: Agencia Canaria de Investigación, Innovación y Sociedad de la Información, Ministerio de Ciencia, Innovación y Universidades (España), Ministerio de Ciencia e Innovación (España)
• Format: Article in Journal/Newspaper
• Language: English
• Published: American Geophysical Union 2022
• Subjects: Antarctic; Antarc*; North Atlantic
• Online Access: http://hdl.handle.net/10261/284645; https://doi.org/10.1029/2022GB007475; https://doi.org/10.13039/501100007757; https://doi.org/10.13039/501100004837

20 pages, 5 figures.-- Open access The change in anthropogenic CO2 (Canth) in the Atlantic Ocean is linked to the Atlantic Meridional Overturning Circulation (AMOC), that redistributes Canth meridionally and in depth. We have employed direct biogeochemical measurements and hydrographic data from the last 30 years, adjusted using inverse models for each decade with both physical and biogeochemical constraints. We then have computed the meridional transports and the vertical transports between two sections at the interphases by advection and diffusion. We have focused on the repeated sections at three latitudes—30°S, 24, and 55°N, dividing the Atlantic into two boxes. We have divided the net transport into upper, deep and abyssal layers, with an upper and abyssal northward transport of Canth and a southward component in deep layers. The change in time in the net transports of Canth appears to be mainly due to modifications in the transport of upper layers. The lower layer of the AMOC, a combination of deep and abyssal waters, maintain more consistent transports in time. Vertical advection plays an important role in the North Atlantic, exporting Canth from upper to deep layers. In the South Atlantic, the newly formed Antarctic Bottom Water exports Canth from abyssal to deep layers. The strong gradient in Canth concentration at the interphase of upper and deep layers results in a strong vertical diffusion V.C. acknowledges the Agencia Canaria de Investigación, Innovación y Sociedad de la Información (ACIISI) grant program of “Apoyo al personal investigador en formación” TESIS2019010015. V.C. and A.H-G. were supported by the SAGA project (RTI2018-100844-B-C31) funded by the Ministerio de Ciencia, Innovación y Universidades of the Spanish Government. F.F.P. and A.V. were supported by the BOCATS2 (PID2019-104279GB-C21) project funded by MCIN/AEI/10.13039/501100011033 and contributing to WATER:iOS CSIC PTI Peer reviewed