The main objective of this study was to analyse long-term sea-level variation in the Black Sea using PSMSL tide-gauge data and satellite altimetry, and to improve trend estimation using the Extended Kalman Filter (EKF). For this, PSMSL tide-gauge records from 10 stations (1921–2020) and satellite altimetry (GLORYS12V1 / CMEMS) for 1993–2020 were used. A linear and quadratic trend analysis was applied to detect long-term and accelerating changes, and an EKF state-space model was implemented to extract level, rate, and acceleration components.
The Key findings of the study show that the sea level along the Black Sea coast has a clear, accelerating rise. EKF estimates match tide-gauge observations extremely well (correlation ~0.99). Satellite altimetry shows weaker agreement in coastal zones due to reduced precision near shorelines. EKF effectively removes noise and provides reliable short-term predictions. This demonstrates the suitability of EKF for regional sea-level monitoring and provides more accurate coastal benchmarks for climate-adaptation planning. The study highlights the need for VLM correction in future analyses to reconcile altimetry and tide-gauge records more precisely.
The applications of such kind of studies can be flood-risk assessment, infrastructure planning, coastal-hazard mitigation, and climate-change studies.