Malvinas-slope water intrusions on the northern Patagonia continental shelf

• Published in: Ocean Science
• Main Authors: Piola, A. R., Martínez Avellaneda, N., Guerrero, R. A., Jardón, Fernanda P., Palma, E. D., Romero, S. I.
• Other Authors: Departamento de Ciencias de la Atmosfera y los Oceanos (DCAO), Facultad de Ciencias Exactas y Naturales Buenos Aires (FCEyN), Universidad de Buenos Aires Buenos Aires (UBA)-Universidad de Buenos Aires Buenos Aires (UBA), Servicio de Hidrografia Naval, Servicio de Hydrografia Naval, Institut für Meereskunde Hamburg, Universität Hamburg (UHH), Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS-PSL), Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales Toulouse (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales Toulouse (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Universidad Nacional del Sur Argentina (UNS), Instituto Argentino de Oceanografía Bahía Blanca (IADO), Consejo Nacional de Investigaciones Científicas y Técnicas Buenos Aires (CONICET)-Universidad Nacional del Sur Argentina (UNS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2010
• Subjects: [SDU]Sciences of the Universe [physics]; Drake Passage
• Online Access: https://hal.science/hal-04115118; https://hal.science/hal-04115118/document; https://hal.science/hal-04115118/file/os-6-345-2010.pdf; https://doi.org/10.5194/os-6-345-2010

International audience The Patagonia continental shelf located off southeastern South America is bounded offshore by the Malvinas Current, which extends northward from northern Drake Passage (~55° S) to nearly 38° S. The transition between relatively warm-fresh shelf waters and Subantarctic Waters from the western boundary current is characterized by a thermohaline front extending nearly 2500 km. We use satellite derived sea surface temperature, and chlorophyll-a data combined with hydrographic and surface drifter data to document the intrusions of slope waters onto the continental shelf near 41° S. These intrusions create vertically coherent localized negative temperature and positive salinity anomalies extending onshore about 150 km from the shelf break. The region is associated with a center of action of the first mode of non-seasonal sea surface temperature variability and also relatively high chlorophyll-a variability, suggesting that the intrusions are important in promoting the local development of phytoplankton. The generation of slope water penetrations at this location may be triggered by the inshore excursion of the 100 m isobath, which appears to steer the Malvinas Current waters over the outer shelf.