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Submesoscale structures fill the ocean surface, and recent numerical simulations and indirect observations suggest that they may extend to the ocean interior. It remains unclear, however, how far-reaching their impact may be—in both space and time, from weather to climate scales. Here transport pathways and the ultimate fate of the Irminger Current water from the continental slope to Labrador Sea interior are investigated through regional ocean simulations. Submesoscale processes modulate this transport and in turn the stratification of the Labrador Sea interior, by controlling the characteristics of the coherent vortices formed along West Greenland. Submesoscale circulations modify and control the Labrador Sea contribution to the global meridional overturning, with a linear relationship between time-averaged near surface vorticity and/or frontogenetic tendency along the west coast of Greenland, and volume of convected water. This research puts into contest the lesser role of the Labrador Sea in the overall control of the state of the MOC argued through the analysis of recent OSNAP (Overturning in the Subpolar North Atlantic Program) data with respect to estimates from climate models. It also confirms that submesoscale turbulence scales-up to climate relevance, pointing to the urgency of including its advective contribution in Earth systems models.

Photonuclear reactions of light nuclei below a mass of$$A=60$$$A=60$are planned to be studied experimentally and theoretically with the PANDORA (Photo-Absorption of Nuclei and Decay Observation for Reactions in Astrophysics) project. Two experimental methods, virtual photon excitation by proton scattering and real photo absorption by a high-brilliance$$\gamma $$$\gamma$-ray beam produced by laser Compton scattering, will be applied to measure the photoabsorption cross sections and decay branching ratio of each decay channel as a function of the photon energy. Several nuclear models, e.g. anti-symmetrized molecular dynamics, mean-field and beyond-mean-field models, a large-scale shell model, and ab initio models, will be employed to predict the photonuclear reactions. The uncertainty in the model predictions will be evaluated based on the discrepancies between the model predictions and experimental data. The data and predictions will be implemented in the general reaction calculation code, . The results will be applied to the simulation of the photo-disintegration process of ultra-high-energy cosmic rays in inter-galactic propagation.