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Kelp forests may contribute substantially to ocean carbon sequestration, mainly through transporting kelp carbon away from the coast and into the deep sea. However, it is not clear if and how kelp detritus is transported across the continental shelf. Dense shelf water transport (DSWT) is associated with offshore flows along the seabed and provides an effective mechanism for cross-shelf transport. In this study, we determine how effective DSWT is in exporting kelp detritus beyond the continental shelf edge, by considering the transport of simulated sinking kelp detritus from a region of Australia’s Great Southern Reef. We show that DSWT is the main mechanism that transports simulated kelp detritus past the continental shelf edge, and that export is negligible when DSWT does not occur. We find that 51% per year of simulated kelp detritus is transported past the continental shelf edge, or 17–29% when accounting for decomposition while in transit across the shelf. This is substantially more than initial global estimates. Because DSWT occurs in many mid-latitude locations around the world, where kelp forests are also most productive, export of kelp carbon from the coast could be considerably larger than initially expected.

Waves critically modulate the air‐sea fluxes, and upper‐ocean thermodynamics in a Tropical Cyclone (TC) system. This study improves the modeling of TC intensification by incorporating non‐breaking wave‐induced turbulence and sea spray from breaking waves into an atmosphere‐ocean‐wave coupled model. Notably, wind forecast error decreased by around 10% prior to TCs' peak intensity. The positive feedback of sea spray along with compensatory negative feedback from non‐breaking waves, overall enhanced TCs' intensity. These breaking and non‐breaking wave‐coupled processes consistently cool sea surface temperature, resulting in improvement of the modeled SST. Observed improvements in full‐year TC cases ranging from Categories I to IV in this study suggest that an accurate characterization of ocean wave‐coupled processes is crucial for improving TCs' intensity forecasts and advancing our understanding of severe weather events in both, the atmosphere and ocean. Plain Language Summary Tropical Cyclones (TCs), such as hurricanes and typhoons, are destructive natural disasters that can cause extensive damage. Our study focused on understanding the role of ocean waves and related processes in TCs. Through numerical modeling, we found that ocean waves, specifically breaking and non‐breaking waves, have a substantial influence on TCs' intensity. Breaking waves contribute positively through the production of sea spray droplets, while non‐breaking wave‐induced turbulence has a compensatory negative effect, resulting in an enhancement in TCs' intensity. Incorporating both wave mechanisms into the models improved the accuracy of TCs' intensity and their underlying sea surface temperature. By highlighting the importance of ocean wave‐coupled physics, we aim to enhance our understanding of TCs and improve disaster preparedness to mitigate their impacts on coastal communities. Key Points Full‐year regional hindcast of Tropical Cyclones (TCs) at the North West Australia Inclusion of wave‐coupled processes improves TCs modeling, by reducing forecast errors and enhancing rapid intensification simulations Sea spray increases TC development while nonbreaking wave turbulence has the opposite effect with the first process dominating

The land–sea breeze (LSB) system, driven by the thermal contrast between the land and the adjacent ocean is a widely known atmospheric phenomenon, which occurs in coastal regions globally. South-west Australia experiences a persistent and one of the strongest LSB systems globally with maximum wind speeds associated with the LSB system often exceeding 15 ms−1. In this paper, using field measurements and numerical simulations, we examine: (1) the local winds associated with the land–sea breeze with an emphasis on the ocean; and, (2) the response of the surface currents to the diurnal wind forcing. The measurements indicated that the wind speeds decreased between midnight and 0400 and increased rapidly after 1100, reaching maxima >10 ms−1 around 1800) associated with the sea breeze and decreased to midnight. Wind directions were such that they were blowing from south-east (120°) in the morning and changed to almost southerly (~200°) in the afternoon. Decomposition of the wind record to the diurnal and synoptic components indicated that the diurnal component of winds (i.e., LSB) was oriented along the south-west to north-east axis. However, the stronger synoptic winds were from the south-east to south quadrant and in combination with the LSB, the winds consisted of a strong southerly component. We examined the evolution, horizontal extent, and propagation properties of sea breeze fronts for characteristic LSB cycles and the sea breeze cell propagating offshore and inland. The results indicated that the sea breeze cell was initiated in the morning in a small area, close to 33° S, 115.5° E, with a width of ~25 km and expanded onshore, offshore and alongshore. The sea breeze cell expanded faster (30 kmh−1) and farther (120 km) in the offshore direction than in the onshore direction (10 kmh−1 and 30–40 km). Winds during the LSB cycle followed a counterclockwise rotation that was also reflected in the surface currents. The winds and surface currents rotated anticlockwise with the surface currents responding almost instantaneously to changes in wind forcing but were modified by topography. The diurnal surface currents were enhanced due to the resonance between the LSB forcing and the inertial response.

This study aims to enhance our understanding of the bora-driven dense-water dynamics in the Adriatic Sea using different state-of-the-art modelling approaches during the 2014–2015 period. Practically, we analyse and compare the results of the following four different simulations: the latest reanalysis product for the Mediterranean Sea, a recently evaluated fine-resolution atmosphere–ocean Adriatic Sea climate model, and a long-time-running Adriatic Sea atmosphere–ocean forecast model used in both hindcast and data assimilation (with 4 d cycles) modes. As a first step, we evaluate the resolved physics in each simulation by focusing on the performance of the models. Then, we derive the general conditions in the ocean and the atmosphere during the investigated period. Finally, we analyse in detail the numerical reproduction of the dense-water dynamics as seen by the four simulations. The likely prerequisites for proper modelling of the ocean circulation in the Adriatic basin, including a kilometre-scale atmosphere–ocean approach, non-hydrostatic atmospheric models, fine vertical resolutions in both atmosphere and ocean, and the location and forcing of the open boundary conditions, are thus discussed in the context of the different simulations. In conclusion, a 31-year-long run of the fine-resolution Adriatic Sea climate model is found to be able to outperform most aspects of the reanalysis product, the short-term hindcast, and the data-assimilated simulation in reproducing the dense-water dynamics in the Adriatic Sea.

The paper aims to estimate wintertime thermohaline properties and dense water formation (DWF) dynamics, rates, and transports in the northern and middle Adriatic between 2008 and 2015. The focus has also been directed to the year-to-year differences between two known DWF sites located on the northern Adriatic shelf and in the eastern coastal region. The estimates are based on a high-resolution interannual simulation by Regional Ocean Modelling System, one-way forced by the meteorological Aladin/HR operational mesoscale model, with new river climatology imposed particularly at the eastern Adriatic coast. Substantial interannual variability in wintertime bottom densities has been found, varying for more than 1.0 kg m−3 among years. Such variations are largely associated with the January–February heat losses, while atmospheric preconditioning in November–December seems to have a little effect on the DWF rates. By contrast, salinity is preconditioning the DWF in the eastern coastal site. That has been found relevant for DWF rates during extraordinary winters, as in the case of 2012. Contribution of a coastal site to the overall DWF rates in other years has not been substantial. Finally, a saw-tooth-like pattern in thermohaline time series has been found in observations and reproduced by the numerical model at the bottom of the middle Adriatic depressions.

The aim of this work was to study Chrystal and Proudman resonances in a simple closed basin and to explore and compare how well the two resonant mechanisms are reproduced with different, nowadays widely used, numerical ocean models. The test case was based on air pressure disturbances of two commonly used shapes (a sinusoidal and a boxcar), having various wave lengths, and propagating at different speeds. Our test domain was a closed rectangular basin, 300 km long with a uniform depth of 50 m, with the theoretical analytical solution available for benchmark. In total, 2250 simulations were performed for each of the three different numerical models: ADCIRC, SCHISM and ROMS. During each of the simulations, we recorded water level anomalies and computed the integral of the energy density spectrum for a number of points distributed along the basin. We have successfully documented the transition from Proudman to Chrystal resonance that occurs for a sinusoidal air pressure disturbance having a wavelength between one and two basin lengths. An inter-model comparison of the results shows that different models represent the two resonant phenomena in a slightly different way. For Chrystal resonance, all the models showed similar behavior; however, ADCIRC model providing slightly higher values of the mean resonant period than the other two models. In the case of Proudman resonance, the most consistent results, closest to the analytical solution, were obtained using ROMS model, which reproduced the mean resonant speed equal to 22.00 m/s— i.e., close to the theoretical value of 22.15 m/s. ADCIRC and SCHISM models showed small deviations from that value, with the mean speed being slightly lower—21.97 m/s (ADCIRC) and 21.93 m/s (SCHISM). The findings may seem small but could play an important role when resonance is a crucial process producing enhancing effects by two orders of magnitude (i.e., meteotsunamis).

An ocean surface currents forecasting system, based on a Self-Organizing Maps (SOM) neural network algorithm, high-frequency (HF) ocean radar measurements and numerical weather prediction (NWP) products, has been developed for a coastal area of the northern Adriatic and compared with operational ROMS-derived surface currents. The two systems differ significantly in architecture and algorithms, being based on either unsupervised learning techniques or ocean physics. To compare performance of the two methods, their forecasting skills were tested on independent datasets. The SOM-based forecasting system has a slightly better forecasting skill, especially during strong wind conditions, with potential for further improvement when data sets of higher quality and longer duration are used for training.

On the morning of 21 June 1978, exceptional sea level oscillations with a trough‐to‐crest height of 6 m and a period of 10–20 min were observed in Vela Luka Bay. Slightly less pronounced variability was observed in a wider middle and south Adriatic east coastal area and, with some delay, along the west coast. In this paper, one of the original hypotheses put forward to interpret the event, relating it to a mesoscale air pressure disturbance, is reconsidered by using all the available data as well as state‐of‐the‐art meteorological and oceanographic models. A fresh look at the meteorological data confirms that the atmospheric disturbance propagated at about 22 m/s in a northeastward direction. Additionally, the data suggest that it had the shape of the boxcar function characterized by an air pressure offset of 3 mbar and duration of 10 min. The meteorological model employed (Weather Research and Forecasting (WRF)‐Advanced Research WRF) proves unable to reproduce the mesoscale disturbance coinciding with the surge, but it shows that the background atmospheric conditions were favorable for the development of such disturbances. The oceanographic model Advanced Circulation Model for Shelves, Coasts and Estuaries (two‐dimensional depth integrated), forced by the described air pressure disturbance, successfully reproduces sea level variability in Vela Luka Bay reaching a few meters and thus surpassing the inverted barometer response by two orders of magnitude. The enhancement appears to be due to a four‐phase process. The model also suggests that the scattering due to the variable bathymetry and the reflection from the east Adriatic coast resulted in waves that returned towards the west coast and generated considerable sea level activity there.

A series of meteotsunamis hit a few locations in the Mediterranean and Black Seas during 22–27 June 2014. Meteotsunamis were particularly numerous on 25 and 26 June in the Adriatic Sea, where at least six harbours and bays were stricken by powerful waves: strongest events occurred in Vela Luka (Korčula Island), a known meteotsunami hot-spot, where waves reached height of ~3 m, and in Rijeka dubrovačka Bay, where strong ~5 m/s currents accompanied ~2.5 m high waves. Intensification of high-frequency sea level activity was observed at both the eastern and western Adriatic tide gauge stations, with maximum recorded wave heights reaching ~68 cm (Ortona, Italy). A series of individual air pressure disturbances characterized by pronounced rates of air pressure change (up to 2.4 hPa/5 min), limited spatial extent (~50 km) and high temporal variability, propagated over the Adriatic on 2 days in question. Numerical hydrodynamic model SCHISM forced by measured and idealised air pressure disturbances was utilised to reproduce the observed Adriatic sea level response. Several important conclusions were reached: (1) meteotsunamis occurring at various parts of the coast were generated by different atmospheric air pressure disturbances; (2) topographic influence can be removed from sea level spectra by computing spectral signal-to-background ratios; the result, being related to the external forcing, resembles atmospheric pressure spectra; (3) sea response is strongly dependant on details of atmospheric forcing; and (4) over complex bathymetries, like the middle and south Adriatic ones, numerous effects, including Proudman resonance, edge waves, strong topographical enhancement and refractions on the islands placed on the pathway of atmospheric disturbances should be taken into account to fully understand meteotsunami generation and dynamics. An in-depth numerical study is planned to supplement the latter conclusion and to quantify contribution of each process.

The study describes recent decadal changes (2008–2017) in the landing biomass, fishing effort and CPUE (kg/day) data of European lobster Homarus gammarus in the eastern Adriatic Sea region, and relates these changes to increases of sea bottom temperatures detected at long-term in situ stations and modelled by an ocean numerical model (ROMS, Regional Ocean Modelling System). Modelling results were further used to quantify spatial and temporal differences of bottom temperature changes over different fishing zones. Trends of sea bottom temperature were positive and statistically significant between stations. Temporal trends of landing, effort and CPUE were also positive and significant for the northern Adriatic. Correlation analysis was used to test the relationship between winter and spring sea bottom temperatures and CPUE data of H. gammarus , separately for the northern and central Adriatic Sea, resulting in statistically significant correlations for both areas. Whether the increased CPUE in the northern Adriatic is due to increased abundance or catchability is discussed. The observed temperature changes likely reflect climate system changes recognised at the regional level and as such, lobster management measures will need to be revised and updated in the future.