Regional hydrography and dynamics at the Galicia-Cantabrian region are described, as well as
its interannual variability in recent decades, from the Spanish Institute of Oceanography systematic monitoring programs and other available data sources. It is found a robust warming trend,
within rates above 0.20°C decade–1
, both in surface ocean waters from the detailed records of
satellite and at intermediate depths from the hydrographical series (down to 1000 m, which is
the depth limit of the intensive sampling carried out from mid 90’s). These trends are related
to recurrent warm periods in the local atmospheric forcing as well as in the formation areas of
intermediate waters that reach the region. The structure of the water column, characterized by
the depth of the mixed layer and surface stratification, shows a strong interannual variability,
standing out the development of an anomalously deep mixed layer in 2005 that notably affected
the properties of intermediate waters in the region. At the continental shelf it is observed a very
distinct pattern between the Galician region, affected by intense upwelling in summertime and
the winter arrival of strong inflows related to the Iberian Poleward Current, and the Cantabrian
Sea, where these dynamical effects are much weaker. As a consequence, the extent of the annual
cycles of surface temperature increases dramatically from Galicia towards the eastern Bay of
Biscay. Finally, a climatological record of deep water circulation from the longest series of moorings available in the region is presented.Versión del edito
