The Levantine Intermediate Water in the western Mediterranean and its interactions with the Algerian Gyres: insights from 60 years of observation

Type Article
Date 2022-07
Language English
Author(s) Mallil Katia1, 2, Testor PierreORCID1, Bosse Anthony3, Margirier Félix4, Houpert Loic5, Le Goff Hervé1, Mortier Laurent1, Louanchi Ferial2
Affiliation(s) 1 : Laboratoire d’Océanographie et du Climat: Expérimentations et Approches Numériques (LOCEAN, UMR 7159): CNRS/SU/MNHN/IRD, 75005, Paris, France
2 : Ecole Nationale Supérieure des Sciences de la Mer et de l’Aménagement du Littoral (ENSSMAL), Laboratoire des Ecosystèmes Marins et Littoraux (EcosysMarL), 16320, Alger, Algeria
3 : Aix-Marseille Université, Université de Toulon, CNRS, IRD, MIO UM110, 13288, Marseille, France
4 : School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia, USA
5 : OSE Engineering, 78470, Saint-Rémy-lès-Chevreuse, France
Source Ocean Science (1812-0784) (Copernicus GmbH), 2022-07 , Vol. 18 , N. 4 , P. 937-952
DOI 10.5194/os-18-937-2022
WOS© Times Cited 3
Note Special issue : Advances in interdisciplinary studies at multiple scales in the Mediterranean Sea Editor(s): Alejandro Orfila, Vanessa Cardin, Sarantis Sofianos, Gianmaria Sannino, and Anna Rubio
Abstract

The presence of two large scale cyclonic gyres in the Algerian basin influences the general and eddy circulation, but their effect on water mass transfer remain poorly characterized. Our study has confirmed the presence of these gyres using the first direct current measurements of the whole water column collected during the SOMBA-GE2014 cruise, specifically designed to investigate these gyres. Using cruise sections and a climatology from 60 years of in situ measurements, we have also shown the effect of these gyres on the distribution at intermediate depth of Levantine Intermediate Water (LIW) with warmer (~0.15 °C) and saltier (~0.02 g.kg−1) characteristics in the Algerian basin than in the Provençal basin. The Algerian gyres also impact horizontal density gradients with sinking of the isopycnals at the gyres’ centres. Temporal cross-correlation of LIW potential temperature referenced to the signal observed south of Sardinia reveal timescale of transit of 4 months to get to the centre of the Algerian basin.

The LIW temperature and salinity trends over various periods are estimated to: +0.0017 ± 0.0014 °C.year−1 and +0.0017 ± 0.0003 year−1 respectively over the 1960–2017 period, and accelerating to +0.059 ± 0.072 °C.year−1 and +0.013 ± 0.006 year−1 over the 2013–2017 period.

Full Text
File Pages Size Access
Preprint 26 20 MB Open access
Publisher's official version 16 13 MB Open access
Top of the page

How to cite 

Mallil Katia, Testor Pierre, Bosse Anthony, Margirier Félix, Houpert Loic, Le Goff Hervé, Mortier Laurent, Louanchi Ferial (2022). The Levantine Intermediate Water in the western Mediterranean and its interactions with the Algerian Gyres: insights from 60 years of observation. Ocean Science, 18(4), 937-952. Publisher's official version : https://doi.org/10.5194/os-18-937-2022 , Open Access version : https://archimer.ifremer.fr/doc/00741/85326/