Seasonal variability of the intermediate water masses in the Gulf of Cadiz: implications of the Antarctic and Subartic seesaw model

• Main Authors: Roque, David, Parras-Berrocal, Iván, Bruno, Miguel, Sánchez-Leal, Ricardo Félix, Hernández Molina, Francisco Javier
• Format: Article in Journal/Newspaper
• Language: English
• Published: Copernicus GmbH 2019
• Subjects: Intermediate Water Mass circulation; Medio Marino y Protección Ambiental; Sede Central IEO; Seasonal variability; Antarctic Intermediate Water; Subarctic Intermediate Water; Mediterranean Outflow Water; Gulf of Cádiz; Atlantic meridional overturning circulation; Antarctic; The Antarctic; Antarc*; North Atlantic; Subarctic
• Online Access: http://hdl.handle.net/10508/15391; http://hdl.handle.net/10261/319090; https://os.copernicus.org/articles/15/1381/2019/os-15-1381-2019.pdf; https://doi.org/10.5194/os-2019-8

Global circulation of intermediate water masses has been extensively studied; however, its regional and local circulation along continental margins and variability and implications on sea floor morphologies are still not well known. In this study the intermediate water mass variability in the Gulf of Cádiz and adjacent areas has been analysed and its implications discussed. Remarkable seasonal variations of the Antarctic Intermediate Water (AAIW) and the Subarctic Intermediate Water (SAIW) are determined. During autumn a greater presence of the AAIW seems to be related to a reduction in the presence of SAIW and Eastern North Atlantic Central Water (ENACW). This interaction also affects the Mediterranean Outflow Water (MOW), which is pushed by the AAIW toward the upper continental slope. In the rest of the seasons, the SAIW is the predominant water mass reducing the presence of the AAIW. This seasonal variability for the predominance of these intermediate water masses is explained by a novel model based on the concatenation of several winddriven processes acting during the different seasons. Our finding is important for a better understanding of regional intermediate water mass variability with implications in the Atlantic Meridional Overturning Circulation (AMOC) but further research is needed in order to decode their changes during the geological past and their role, especially related to the AAIW, in controlling both the morphology and the sedimentation along the continental slopes. Sí