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Wind roses for Vaccarès (Tour-du-Valat station, hourly data over 13 months) and Berre (Marignane station, tree-hourly data over 17 months) lagoons. Wind roses show the the occurrence of wind directions as well as their speeds for both sites : in Vaccarès lagoon main wind directions are NNW and SE up to 20 m/s, and in Berre lagoon, NW winds over 20 m/s and SE up to 20 m/s.

Wind roses for Vaccarès (Tour-du-Valat station, hourly data over 13 months) and Berre (Marignane station, tree-hourly data over 17 months) lagoons. Wind roses show the the occurrence of wind directions as well as their speeds for both sites : in Vaccarès lagoon main wind directions are NNW and SE up to 20 m/s, and in Berre lagoon, NW winds over 20 m/s and SE up to 20 m/s.

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Article
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The present paper is specifically focused on enclosed or semi-enclosed basins where the wind is the dominant driver of water surface tilting, leading to the so-called wind tide contributing to water levels rise. Wind-induced free surface tilting is studied using the 1-D steady form of the depth-averaged shallow water (Saint-Venant) momentum equatio...

Contexts in source publication

Context 1
... statistics during both measurement campaigns are depicted in figure 2. Two dominant 165 wind regimes are observed: NW or NNW winds (mistral) and SE winds. ...
Context 2
... statistics during both measurement campaigns are depicted in figure 2. Two dominant wind regimes are observed: NW or NNW winds (mistral) and SE winds. ...

Citations

... The impact of wind is rarely considered when describing the multiple and complex mechanisms driving the morphodynamics of intermittent estuaries, even though wind can have a considerable influence on the internal lagoon morphology [42,43]. This is especially important in shallow basins where wind forcing can produce surges of significant amplitude [44][45][46][47][48]. These surges can be comparable in magnitude to the effects produced by river discharges and could thus potentially contribute to controlling an intermittent estuary if the surge is directed toward the barrier. ...
... In addition to lowering the beach profile due to erosion processes, offshore winds cause a tilting of the lagoon water surface towards the barrier (Figure 12b); strong offshore winds can blow for weeks during this period. The amplitude of these surges is controlled by the shape of the basin (area and depth) as well as by the wind speed [44][45][46][47][48]. The surges are intensified by increasing basin length, higher wind speed, and increasingly shallow water depth. ...
Article
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This study focuses on the dynamics of an intermittent estuary in a wave-dominated (mi-crotidal) area, with low fluvial discharges and strong dominant offshore wind regimes. The aims are to understand the effect of these particular environmental factors in the dynamics of such estuaries. The results allow us to propose a synthetic morphodynamic model of evolution whereby opening phases are predominantly controlled by offshore winds, which have a significant influence in the northern Mediterranean. Inputs from rainfall/karst discharge and the overtopping of storm waves cause the lagoon to fill. Closing phases are controlled by the slight easterly swell which forms a berm at the inlet entrance. On occasion, major storms can also contribute to barrier opening. Nevertheless , offshore wind remains the main controlling factor allowing the surge of lagoon waters behind the beach barrier and the lowering of the berm by wind deflation. This leads to opening of the barrier due to the overflow of lagoon waters at the beach megacusp horns, thus connecting the sub-aerial beach with the inner bar system that is developed on topographically low sectors of the barrier. To the best of the authors' knowledge, this type of estuary is not described in the literature.
... Although the seashore of the Rhône Delta is subject to a micro-tidal regime (the difference between the lowest and highest value of astronomic tide is 0.42 m, see [25]), the "Vaccarès lagoon system" is not impacted by a tidal regime, [26], due to the small size of the sluice gates in comparison with the area of the Vaccarès Lagoon System, and to their management, with the opening of more than five sluices carried out to decrease water level and mass of salt into the lagoons (flows from the lagoons into the sea). ...
... Due to their shallow depth, Mediterranean coastal lagoons are generally strongly impacted by the wind in terms of water levels [23]. The duration and intensity of the variations of these levels can be more or less important, depending on the geomorphological characteristics of the lagoons considered, and on the local wind dynamics [26]. The time scales of these tilts generally range from several hours to a few days, requiring continuous monitoring ensured by the use of probes in different locations of the lagoon. ...
... Preliminary modeling studies [45] suggest that an absence of regulation on the Vaccarès Lagoon System, including the permanent opening of the 13 sluice gates of the Fourcade, would lead to high water levels in the lagoons. In combination with the influence of wind [23,26], these high water levels would cause bank erosion and regular flooding of the surrounding areas. This work also suggests that it would lead to a significant and longterm increase in the dissolved salt mass and overall salinities. ...
Article
Full-text available
The Vaccarès Lagoon System, located in the central part of the Rhône Delta (France), is a complex shallow coastal lagoon, exposed to a typical Mediterranean climate and a specific hydrological regime affected by man-controlled exchanges with the sea and agricultural drainage channels. In this article, we report the results obtained by a series of monitoring programs, with different spatial and temporal resolutions. Long-term datasets from 1999 to 2019 with data collected on a monthly basis and a high spatial resolution highlighted the significant spatial heterogeneity in salinity regimes, and helped to determine the long-term evolution of the total mass of dissolved salt. High-frequency surveys allowed to characterize the water levels and salinity dynamics seasonal response to (i) the exchanges with the Mediterranean Sea, (ii) the exchanges with agricultural drainage channels, and (iii) the rain and evaporation. In addition, wind effects on salinity variations are also explored. This work shows how different spatial and temporal monitoring strategies provide complementary information on the dynamic of such a complex system. Results will be useful and provide insight for the management of similar lagoon systems, accommodating for both human activities and ecological stakes in the context of global change.