Validation of Reported Strong Currents in Mamaia Bay (Black Sea) Using Sentinel-1 SAR Data

Synthetic aperture radar (SAR) is a well-known tool for ocean remote sensing, offering detailed information about targeted scenes. This research addresses the significant impact of wind gusts on ocean and lake surface currents and highlights the hazards these currents pose to global shorelines and public safety. Recently, an incident in Romania underscored the urgency of understanding these dynamics. High surface currents affect nearshore water exchange and threaten human life, necessitating this investigation. The technical approach involves analyzing SAR images to verify wind fields and estimate surface currents. Calm water regions appear darker in SAR imagery, while areas affected by breaking waves or high winds show strong backscatter, appearing brighter. The radar imaging model (RIM) uses the Doppler centroid to extract surface current information. Wind speeds and significant gusts are verified from SAR data, and high currents are validated through spatial signatures and histograms. Results show a clear correlation between high wind speeds and surface currents. This study confirms that SAR is effective in detecting and analyzing wind-induced variations in ocean and lake currents, providing vital data for mitigating hazards associated with high surface currents.