Hydrography of the southern Bay of Biscay shelf‐break region: Integrating the multiscale physical variability over the period 1993–2003

摘要: [1] The southern Bay of Biscay (NW Spain) shows a very active hydrography due to the different origins its Central Waters, local modifications exerted on them by continental effects and recurrence mesoscale processes such as slope currents, upwellings eddies. In order assess role sources variability we conducted monthly series CTD sampling in central Cantabrian Sea along coastal-oceanic transect, from 1993 2003. We analyzed spatial hydrographic over timescales. The thermohaline properties Waters varied between those typical subpolar mode Eastern North Atlantic Water (ENACWsp) mode, (BBCW), though there has been clear shift toward BBCW prevalence last years. Iberian Poleward Current (IPC) conveyed subtropical (ENACWst) into region almost every winter. This current may display double-core structure during some extreme events. upper layers ocean showed long-term trend increasing temperature decreasing salinity, accordingly density was decrease. These patterns suggest an enhancement water column stratification. Coastal are important source inshore counteract these changes coast. However, their intensity seems be seasonal pattern changing general advancement upwelling-favorable season.