Continuous Monitoring of Open Ocean Water Levels in Russia: Conceptual projects for the Azov, Black, Caspian, and Baltic Seas

Paper underscores the crucial necessity of undertaking continuous instrumental monitoring of water levels directly within open oceans and regional seas. Such direct open-water measurements are fundamental to investigating severe storm surges, hazardous meteotsunamis, tsunami-induced free-surface deviations, seiches, and complex river runoff. Whilst standardised coastal measurements are regularly conducted, and satellite altimetry provides valuable insights into long-term global sea-level trends, satellite monitoring currently exhibits certain operational limitations owing to orbit timing constraints over specific wave generation areas.Consequently, a pressing scientific and practical requirement exists for direct open-sea observations to accurately calculate, model, and verify wave propagation on timescales ranging from tens of minutes to several hours. The primary practical objective of this research is the provision of timely, reliable early warnings regarding long-wave run-ups and sudden storm surges upon the vulnerable coasts of enclosed and semi-enclosed seas, driven by intense meteorological and(or) seismic factors. This matter is particularly vital given the increasing frequency of hazardous flooding events within the densely populated coastal areas of the Ponto-Caspian region and the Baltic Sea under changing climatic conditions, which necessitates immediate adaptation strategies. Technically, deep-ocean DART-class buoy stations fully satisfy these stringent monitoring criteria, as successfully demonstrated by their practical operation within national experimental networks. Recognising these strict requirements, a comprehensive information programme concept is proffered by the authors, designed to justify precise, data-driven environmental decision-making in assessing regional sea-level changes via a novel instrumental approach.