Mesoscale, interannual, and seasonal hydrological variability over the French continental shelf of the Bay of Biscay during the 1990s

Hydrological processes on the French continental shelf of the Bay of Biscay are strongly influenced by the high freshwater run-offs from the Loire and Gironde rivers, which are expected to result in high variability of salinity distribution. However, this variability is poorly understood owing to the lack of field salinity data. Although some mesoscale structures have been recognized, most have rarely been studied specifically. Similarly, specific studies of the interannual and seasonal haline variability have not yet been carried out. Here, we analyse unpublished hydrological data collected during the 1990s. We describe several mesoscale structures: southern Brittany upwellings, lower salinity lenses (originating from river plume), and the so-called cold pool. The extent of the interannual and seasonal variability of the low salinity (S < 35) surface water is also described, and it is shown how wind and river run-off influence variability (mesoscale, interannual, and seasonal).

Article from Marine Science Symposia Vol. 219 - "Hydrobiological variability in the ICES Area, 1990-1999", symposium held in Edinburgh, 8-10 August 2001. To access  the remaining articles please click on the keyword "MSS Vol. 219".