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This study advances the understanding of climate projection variabilities in the Nemunas River, Curonian Lagoon, and southeastern Baltic Sea continuum by analyzing the output of a coupled ocean and drainage basin modeling system forced by a subset of climate models. A dataset from a downscaled high-resolution regional atmospheric climate model driven by four different global climate models was bias-corrected and used to set up the hydrological (Soil and Water Assessment Tool, SWAT) and hydrodynamic (Shallow water HYdrodynamic Finite Element Model, SHYFEM) modeling system. This study investigates the variability and trends in environmental parameters such as water fluxes, timing, nutrient load, water temperature, ice cover, and saltwater intrusions under Representative Concentration Pathway 4.5 and 8.5 scenarios. The analysis highlights the differences among model results underscoring the inherent uncertainties in projecting climatic impacts, hence highlighting the necessity of using multi-model ensembles to improve the accuracy of climate change impact assessments. Modeling results were used to evaluate the possible environmental impact due to climate change through the analysis of the cold-water fish species reproduction season. We analyze the duration of cold periods (<1.5 °C) as a thermal window for burbot (Lota lota L.) spawning, calculated assuming different climate forcing scenarios and models. The analysis indicated coherent shrinking of the cold period and presence of changepoints during historical and different periods in the future; however, not all trends reach statistical significance, and due to high variability within the projections, they are less reliable. This means there is a considerable amount of uncertainty in these projections, highlighting the difficulty of making reliable climate change impact assessments. [ABSTRACT FROM AUTHOR]

This study advances the understanding of climate projection uncertainties in the Nemunas River, Curonian Lagoon, and southeastern Baltic Sea continuum by analyzing a subset of climate models, focusing on a coupled ocean and drainage basin model. Four downscaled and bias-corrected high-resolution regional atmospheric climate models were used to set up the hydrological (SWAT) and hydrodynamic (SHYFEM) modeling system. This study investigates the variability and trends in environmental parameters such as water fluxes, timing, nutrient load, water temperature, ice cover, and saltwater intrusions under Representative Concentration Pathway 4.5 and 8.5 scenarios. The analysis highlights the variability among model results underscoring the inherent uncertainties in forecasting climatic impacts, hence highlighting the necessity of using multi-model ensembles to improve the accuracy of climate change impact assessments. Additionally, modeling results were used to evaluate the possible environmental impact due to climate change through the analysis of the cold water fish species reproduction season. We analyze the duration of cold periods (<1.5 °C) as a thermal window for burbot spawning, calculated assuming different climate forcing scenarios and models. The analysis indicated coherent shrinking of the cold period and presence of the changepoints during historical and different periods in the future, however, not all trends reach statistical significance, and due to high variability within the projections, they are less reliable. This means there is a considerable amount of uncertainty in these projections, highlighting the difficulty in making reliable climate change impact assessments. [ABSTRACT FROM AUTHOR]

A MATLAB routine, based on a Double Multiple Stream Tube model, developed to quickly predict the performance of cross-flow hydrokinetic turbine, here is presented. The routine evaluate flow data obtained with the open-source marine circulation code SHYFEM. The tool can establish the best locations to place tidal devices taking into account bathymetric constraints and the hydrokinetic potential. Hence, it can be used to decide the best set of geometrical parameters. The geometrical variables of our analysis are turbine frontal area, aspect ratio and solidity. Several sub-models, validated with 3D and 2D CFD simulations, reproduce phenomena such as dynamic stall, fluid dynamic tips losses and the lateral deviation of streamlines approaching the turbine. As a case study, the tool is applied to an area of the northern Adriatic Sea. After having identified some suitable sites to exploit the energy resource, we have compared behaviours of different turbines. The set of geometrical parameters that gives the best performance in terms of power coefficient can vary considering several locations. Conversely, the power production is always greater for turbine with low aspect ratio (for a fixed solidity and area). Indeed, shorter devices benefit from higher hydrokinetic potentials at the top of the water column.

On November 12, 2019, an exceptional flood event took place in Venice, second only to the one that occurred on November 4, 1966. The sea level reached a peak value of 1.89 m above the local datum determining the flooding of almost 90% of the pedestrian surface of the historical city. Several processes concurred to raise the water level in Venice and the northern Adriatic Sea on November 12, 2019. Among these, a fast‐moving mesoscale cyclone travelled at about 12 m ·$$ \cdotp $$ s−1$$ {}^{-1} $$ in the northwestward direction over the northern Adriatic Sea, raising the sea levels at the shore in front of the Lagoon of Venice. High‐resolution numerical simulations indicated that atmosphere–ocean resonance occurred on November 12, 2019, generating a meteotsunami‐like wave that contributed significantly to the extreme sea level in Venice. The relative contributions of the wind and air pressure to the peak sea level were also estimated. Additional numerical experiments were performed to prove the occurrence of Proudman resonance and to determine a transfer function of such high‐frequency sea‐level perturbations for the Lagoon of Venice. [ABSTRACT FROM AUTHOR]