BUSCADOR RECOLECTA

Digital.CSIC. Repositorio Institucional del CSIC

oai:digital.csic.es:10261/287817

Poster.-- Clivar 2023, Towards an integrated view of climate, 24-26 January, Madrid, The wave regime in the NW Iberia coastal upwelling system is closely related to the seasonal wind regime (Villacieros-Robineau et al., 2019 and 2021). Under upwelling conditions (prevailing northerly winds, spring-summer), swell and wind sea come mainly from NW directions. When southerly winds prevail (downwelling conditions, autumn-winter), swell comes from WNW while wind sea comes from SW directions. The inner areas of coastal bays (rias) of this region are protected from the NW and exposed to the SW, being more vulnerable to the change in the shelf wave direction than the open coast. The wave regime on the shelf and in one of these bays, the Ría de Vigo, was studied between June 2013 and August 2014, using data from an Acoustic Doppler Current Profiler (ADCP; 600 kHz RDI Workhorse Sentinel), a wave-gauge (Vigo Miros Radar), a met-ocean buoy (Silleiro Seawatch buoy), and model results (Copernicus IBI-WAV Reanalysis and SIMAR hindcast). Our results indicate that swell is almost always attenuated when entering the bay, and wave height inside the ria depends mostly on shelf wind sea variability. During the upwelling season, both swell and wind sea barely enter the ria, and wave heights inside the ria are small (Hs50% = 0.21 m). During the downwelling season, shelf wind sea directly enters the ria, contributing more to the total wave height, which achieves its maximum values (Hs50% = 0.46 m). There is a cumulative action of wave and wind-driven currents (wave-current coupling, WCC) that is strongest during the downwelling season. The WCC entails an increase in seabed energy, which could reinforce bottom remineralization, produce changes in the ecophysiology of benthic organisms, and have potential effects on other essential ecosystem services and human activities (Villacieros-Robineau et al., 2017, 2022). The inter-annual variability (2009–2016) of winter wave height and WCC in the ria is associated with the combined role played by the North Atlantic Oscillation (NAO) and West Europe Pressure Anomaly (WEPA) indices. The highest waves and strongest WCC occur when negative NAO and positive WEPA phases coincide and can have potentially relevant repercussions on the ecosystem services of the ria, N. Villacieros-Robineau and P. C. Pardo were funded by MCIN/AEI /10.13039/501100011033 through a Juan de la Cierva-Formación postdoctoral fellowship (FJCI-2017–34290) and a Personal Técnico de Apoyo grant (PTA2019-017492-I), respectively. Projects: STRAMIX (CTM2012-35155) and STRAUSS (PID2019-106008RB-C21) funded by MCIN/AEI/10.13039/501100011033, No