On the seasonal variability of the Canary Current and the Atlantic Meridional Overturning Circulation
Perez-Hernandez, M. Dolores
MetadataShow full item record
KeywordCanary Current; African slope; Seasonal cycle; Atlantic Meridional Overturning Circulation; Rossby wave
The Atlantic Meridional Overturning Circulation (AMOC) is continually monitored along 26°N by the RAPID-MOCHA array. Measurements from this array show a 6.7 Sv seasonal cycle for the AMOC, with a 5.9 Sv contribution from the upper mid-ocean. Recent studies argue that the dynamics of the eastern Atlantic is the main driver for this seasonal cycle; specifically, Rossby waves excited south of the Canary Islands. Using inverse modeling, hydrographic, mooring, and altimetry data, we describe the seasonal cycle of the ocean mass transport around the Canary Islands and at the eastern boundary, under the influence of the African slope, where eastern component of the RAPID-MOCHA array is situated. We find a seasonal cycle of −4.1 ± 0.5 Sv for the oceanic region of the Canary Current, and +3.7 ± 0.4 Sv at the eastern boundary. This seasonal cycle along the eastern boundary is in agreement with the seasonal cycle of the AMOC that requires the lowest contribution to the transport in the upper mid-ocean to occur in fall. However, we demonstrate that the linear Rossby wave model used previously to explain the seasonal cycle of the AMOC is not robust, since it is extremely sensitive to the choice of the zonal range of the wind stress curl and produces the same results with a Rossby wave speed of zero. We demonstrate that the seasonal cycle of the eastern boundary is due to the recirculation of the Canary Current and to the seasonal cycle of the poleward flow that characterizes the eastern boundaries of the oceans.
Author Posting. © American Geophysical Union, 2017. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Oceans 122 (2017): 4518–4538, doi:10.1002/2017JC012774.
Suggested CitationArticle: Vélez-Belchí, Pedro, Perez-Hernandez, M. Dolores, Casanova-Masjoan, Maria, Cana, Luis, Hernández-Guerra, Alonso, "On the seasonal variability of the Canary Current and the Atlantic Meridional Overturning Circulation", Journal of Geophysical Research: Oceans 122 (2017): 4518–4538, DOI:10.1002/2017JC012774, https://hdl.handle.net/1912/9197
Showing items related by title, author, creator and subject.
Hernandez-Guerra, Alonso; Joyce, Terrence M.; Fraile-Nuez, Eugenio; Velez-Belchi, Pedro (2009-08-06)Using a variety of oceanographic data, including direct volume transports in the Florida 19 Strait, and Argo float profiles and drift velocities at 24 and 36N in the North Atlantic, inverse calculations are presented in ...
Near-surface transport pathways in the north Atlantic Ocean : looking for throughput from the subtropical to the subpolar gyre Rypina, Irina I.; Pratt, Lawrence J.; Lozier, M. Susan (American Meteorological Society, 2011-05)Motivated by discrepancies between Eulerian transport estimates and the behavior of Lagrangian surface drifters, near-surface transport pathways and processes in the North Atlantic are studied using a combination of data, ...
Toole, John M.; Andres, Magdalena; Le Bras, Isabela A.; Joyce, Terrence M.; McCartney, Michael S. (John Wiley & Sons, 2017-09-15)A moored array spanning the continental slope southeast of Cape Cod sampled the equatorward-flowing Deep Western Boundary Current (DWBC) for a 10 year period: May 2004 to May 2014. Daily profiles of subinertial velocity, ...