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arXiv · 1107.5919

The Productive Ligurian Pool

E. Casella·P. Tepisch·X. Couvelard·R. M. A. Caldeira
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Abstract

In contrast with the behavior of the eddies in the open-ocean, the sub-mesoscale eddies generated in the constricted Ligurian Basin (NW Mediterranean), are unproductive but their combined effect, arranged in a rim-like fashion, contributes to the containment of a Productive Ligurian Pool (PLP). Data de- rived from MODIS satellite sensor showed persistent higher chlorophyll con- centrations in the centre of the basin, concurrent with high EKE values in its surroundings, derived from AVISO altimetry merged products. This sug- gested that this 'productive pool' is maintained by the intense (sub)mesoscale eddy activity in the rim. Numerical realistic experiments, using a Regional Ocean Model System, forced by MERCATOR and by a high-resolution COSMO- l7 atmospheric model, also showed that most of the sub-mesoscale eddies, during 2009 and 2010, are concentrated in the rim surrounding the basin, contributing to the formation of a basin-scale cyclonic gyre. We hypothesized that the interaction between eddies in the rim might contribute to import of nutrients into the pool in two ways: (i) by advection of nutrients from the nearby coastal regions into the pool; (ii) by concentrating eddy upwelled nu- trients inside the pool; or by a combination thereof.

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E. Casella, P. Tepisch, X. Couvelard, R. M. A. Caldeira. 2011-07-29. The Productive Ligurian Pool. https://arxiv.org/abs/1107.5919

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