A multiplatform analysis of wind- and river-driven surface circulation in the Gulf of Trieste (northern Adriatic Sea)

This work was presented at the MoonGOS meeting in Lisbon from 2 to 4 December 2025.The study analyses the dynamics of the Gulf of Trieste under different environmental conditions, focusing on the extreme events of autumn 2023. By integrating river discharge, meteorological data, HF radar measurements, and MITgcm simulations, it shows that intense Isonzo/Soča floods significantly altered circulation patterns, generating anticyclonic and cyclonic features in different areas of the gulf. In the absence of river input, winds play a key role: Bora strengthens cyclonic and offshore circulation, while southerly winds enhance onshore flow, sea level rise, and surface current intensity. Subsequent drifter deployments (2024–2025) confirmed the consistency of HF radar observations, providing a comprehensive view of how freshwater input and wind forcing jointly regulate surface dynamics in the Gulf of Trieste. This study was funded by the European Union - NextGenerationEU, in the framework of the iNEST - Interconnected Nord-Est Innovation Ecosystem (iNEST ECS00000043 – CUP F43C22000190006) - Project NEREIDES-Bando Giovani Ricercatori. The views and opinions expressed are solely those of the authors and do not necessarily reflect those of the European Union, nor can the European Union be held responsible for them. The dataset was developed as part of the activities carried out by Spoke 8, Research Topic RT1 (Biology of hydrosphere ecosystems), Task S3_RT1.1.3 (Filling knowledge gaps in observation).