The world’s oceans play a crucial role in regulating Earth’s climate by absorbing a substantial fraction of atmospheric CO₂. Air–sea CO₂ exchange, therefore, represents a fundamental component of the global carbon cycle, yet its understanding and quantification remain highly uncertain, particularly under energetic conditions and in regional seas. Observations indicate that enhanced CO₂ fluxes during high sea states cannot be explained by interfacial turbulence alone, pointing to a contribution from breaking wave processes. Wave breaking entrains air into the upper ocean in the form of bubble plumes, providing an additional pathway for gas transfer.This PhD project aims to investigate how the physical control from ocean waves on the air–sea CO₂ exchange, by linking environmental forcing, surface whitecap coverage, air bubble production and penetration in the upper ocean. The research will be based on direct field observations collected from a marine research tower using innovative instrumentation. The analysis will quantify wave field properties, whitecap coverage, bubble penetration depth, water column conditions, and CO₂ bulk fluxes across different atmosphere and sea regimes. The goal is to derive a comprehensive formulation that represents the air–sea CO₂ exchange. Further, by combining observations with sea modelling, the project will advance the understanding of CO₂ transfer and contribute to improved quantification of CO₂ exchange in regional- and basin-scale models.

The candidate will require a background in marine sciences or related topics. Preferential skills include the analysis of observational data, basic signal processing, and experience with oceanographic and atmospheric variables. Familiarity with numerical modelling as well as programming skills (e.g. MATLAB or Python) will be beneficial. The research requires good scientific writing and communication skills. Proficiency in English is required.

The research activity will be coordinated by Dr Alvise Benetazzo within an interdisciplinary team at CNR with expertise in air–sea interaction, ocean observations, and carbon cycle processes. Dr Zenone will contribute expertise on CO₂ probing and air–sea flux measurements; Dr Barbariol will assist the project by providing support on wave modelling, while Mauro Bastianini will support the interpretation of biological processes and marine carbon cycling. The research environment offers access to a permanent marine research tower, advanced observational instrumentation, and state‑of‑the‑art numerical modelling tools, enabling strong integration between observations and modelling.