Ekman Transport as the Driver of Extreme Interannual Formation Rates of Eighteen Degree Water

• Published in: Journal of Geophysical Research: Oceans
• Main Authors: Li, Ke, Maze, Guillaume, Mercier, Herlé
• Other Authors: Laboratoire d'Océanographie Physique et Spatiale (LOPS), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2022
• Subjects: [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography; North Atlantic
• Online Access: https://hal.archives-ouvertes.fr/hal-03814771; https://hal.archives-ouvertes.fr/hal-03814771/document; https://hal.archives-ouvertes.fr/hal-03814771/file/90674.pdf; https://doi.org/10.1029/2021jc017696

International audience The EDW is a nearly homogeneous water body found in the western subtropical North Atlantic region. That was named after the fact that it maintains a nearly constant temperature around 18°C. The EDW is primarily formed to the west of 45°W, between the Gulf Stream and 30°N (Maze et al., 2009). In this region, the air-sea heat flux in EDW is the key driving mechanism of EDW formation and destruction in the seasonal time scale (Forget et al., 2011; Maze et al., 2009). Maze et al. (2009) showed that in a typical seasonal cycle, intense winter surface buoyancy loss leads to the outcropping of EDW, which is replenished during this period. In the spring and summer, surface buoyancy flux destroys the EDW. Over the 2004-2006 period, Forget et al. (2011) examined the EDW volume and reported that the EDW volume increase peaked at 8.6 Svy (Sverdrup year, 1 Svy = 3.154 × 10 13 m 3) in February, with a total EDW volume increase due to air-sea heat fluxes of 9.3 Svy. The EDW destruction due to air-sea heat fluxes was −4.6 Svy, and that due to mixing was −2.6 Svy. The net annual