Three decades of continuous ocean observations in North Atlantic Spanish waters: The RADIALES time series project, context, achievements and challenges

• Published in: Progress in Oceanography
• Main Authors: Valdés-Santurio, L. (Luis), Bode, A. (Antonio), Latasa, M. (Mikel), Nogueira, E. (Enrique), Somavilla, R. (Raquel), Varela, M.M. (Marta María), González-Pola, C. (César), Casas-Rodríguez, G. (Gerardo)
• Format: Article in Journal/Newspaper
• Language: English
• Published: Centro Oceanográfico de A Coruña 2021
• Subjects: time series; plankton; hydrography; biogeochemistry; nutrients; Galicia; mar Cantábrico; ecosystems; climate; Animal plankton; Phytoplankton; Nordeste; North Atlantic; Northeast Atlantic
• Online Access: http://hdl.handle.net/10508/11927; https://doi.org/10.1016/j.pocean.2021.102671

Ship-based time-series observations provide crucial data for understanding marine ecosystems, improving decision making in ocean and coastal management. However, only a few time series survive for more than a decade. RADIALES is one of the longest multidisciplinary programs in operation in the northern and northwestern coast of Spain. In the last 30Â years, this program collected monthly data on physical, chemical and plankton observations in an array of five sections of stations representative of upwelling and stratified dynamics. Here, the main achievements, including key contributions to ecosystem conservation policies, are summarized. The development of this program, in line with similar initiatives in other countries, included phases focused on the study of seasonality, on comparative analysis, and lately on the analysis of decadal variability and regime shifts. Furthermore, in recent years there was a substantial improvement in the identification of plankton species by genomics. Among the main findings of RADIALES are the quantification of ocean warming at subsurface layers, the determination of climatologies in thermohaline, biogeochemical and biological variables, the inventory of plankton species (from bacteria to zooplankton) and the identification of regionally coherent regime shifts. Baselines defined by RADIALES series were instrumental for the assessment of environmental impacts (e.g. oil spills) and for the support of environmental policies (e.g. Marine Strategy Framework Directive). By contributing to international databases, data from programs as RADIALES combined with new instrumental observations will help to develop a more coherent and comprehensive understanding of the ocean ecosystems, enhancing our ability to detect and forecast risks. IEO, GAIN (Xunta de Galicia) 3,269