Submerged reef structures are increasingly considered for coastal protection, yet the influence of stoss-face opening configuration on irregular-wave transformation remains insufficiently understood. Laboratory experiments were conducted on four reef-type structures with nominal opening ratios of 0.047–0.560 under six irregular-wave conditions in a 50 m wave flume. The analysis examines spatial wave-height evolution, transmission, reflection, coefficient-based residual energy loss, spectral transformation, frequency-dependent transmission, and bicoherence-based quadratic phase coupling. The tested configurations exhibit a consistent ordering: the smaller-opening configurations have lower transmission and larger residual energy-loss coefficients. Using the smallest-opening configuration (RSA) as the reference, the residual energy-loss term accounts for 63.4%–99.5% of the combined differences in the reflected and residual energy-loss proportions across the other configurations. Smaller-opening configurations also show greater attenuation of the dominant spectral peak and short-wave component, together with higher bicoherence near the crest and immediate lee side. Existing transmission formulas do not distinguish the tested configurations when opening configuration is omitted. A dataset-specific tanh-type regression is therefore developed to summarize the dependence of Kt on relative crest submergence and nominal opening ratio within the examined range. These findings describe configuration-dependent free-surface responses under the tested laboratory conditions.

Microplastic (MP) pollution in freshwater ecosystems poses increasing ecological risks, yet basin-scale differences between surface water and sediment remain poorly understood. In this study, we compiled a comprehensive dual-compartment MP database for the Yangtze River Basin (YZB), comprising 679 surface water and 339 sediment samples. By integrating multi-index assessments with SHAP (SHapley Additive exPlanations)-based interpretation, we identified spatial hotspots and key predictors of MP risk. Our results revealed that MP abundance ranged from 0.01 to 44.14 items/L in surface water and from 6 to 51,968 items/kg in sediment. Morphological characteristics and polymer composition also differed markedly between the two compartments: fibers accounted for 52.15 % of MPs in surface water but 34.69 % in sediment, whereas polystyrene (PS) increased from 7.38 % in surface water to 14.43 % in sediment. Hotspot analysis revealed spatially distinct high-risk areas, including previously under-recognized regions such as the Chengdu Plain and Danjiangkou Reservoir. Among the evaluated algorithms, XGBoost showed the best predictive performance, achieving the highest accuracy, recall, F1-score and AUC in both compartments. XGBoost–SHAP analysis indicated that population density and impervious surface area were the key contributors to MP risk in surface water, whereas water network density and geographic factors predominantly influenced MP risk in sediment. SHAP dependence analysis further revealed nonlinear relationships and complex interactions among predictors. Collectively, these findings indicated that both MP risk patterns and their key influencing variables differed between surface water and sediment, highlighting the need for compartment-specific management strategies in large river basins.

This study explores the three-dimensional (3-D) characteristics of oceanic eddies in the Southern Ocean from 2021 to 2023. Copernicus Marine Environment Monitoring Service (CMEMS) GLORYS12V1 product, which provides daily current field data at a (1/12)° grid resolution, is used to identify eddies with radii > 10 km. Additionally, the daily sea level anomaly product from Haiyang-2 (HY-2) altimeters is used to detect mesoscale eddies with radii > 40 km. GLORYS12V1 detects over ten times more surface eddies than HY-2, likely due to its higher spatial and temporal resolution, which allows better identification of smaller-scale features. Both eddy radius and eddy kinetic energy (EKE) differences between layers decrease with depth. At 0.5 m, EKE is lower than at 300–600 m, where it stabilizes. Over 90

Nearshore coastal regions have become popular for floating photovoltaics (FPV) installations. During propagation over seabed topography towards nearshore FPV systems, waves undergo intricate transformations by shoaling, reflection and refraction, potentially influencing hydrodynamic responses of these emerging marine renewable energy structures in ways that are not well understood. Therefore, wave flume experiments and multiscale fully coupled time-domain fluid-structure interaction (FSI) simulations are performed to examine the topography effect on the nonlinear responses of nearshore FPV systems at a field site in the East China Sea. Experimental results reveal that near-resonant wave interactions in coastal regions drive significant energy transfer among different wave frequencies, amplifying the nonlinear dynamic responses of FPV systems by channeling energy toward their natural modes. As a result, second-order heave and pitch responses are amplified by up to 117.87 % and 136.38 % compared to the case without topography, which in turn lead to an increase in mooring tension. Moreover, the topography-induced amplification of nonlinear wave harmonics enhances the surge mean drift of FPV. This enhancement exhibits a negative correlation with the relative FPV length with respect to the wavelength. Comparisons between experiments and fully coupled simulations for irregular waves indicate that neglecting topography causes the FPV dynamic response model to produce inaccurate estimations of heave/pitch motions, while FSI simulations forced by high-fidelity local wave fields predicted by the fully nonlinear Boussinesq wave model are capable of capturing the observed topographic effect. These findings provide the theoretical basis for design consideration of the safe, cost-effective deployment of efficient FPV systems in coastal waters.

This study investigates the hydrodynamic performance of a compact five-flap array of oscillating wave surge converters (OWSCs) using a fully nonlinear open-source computational fluid dynamics (CFD) model, OpenFOAM, with particular attention to the combined effects of wave conditions, wave incident angle, and inter-device spacing. The results show that strong hydrodynamic interactions occur within compact arrays, mainly due to wave-height modulation by diffraction and radiation. Under normal wave incidence, the baseline array produces a maximum local downstream wave-height reduction of 14.15%, while local wave amplification also occurs within the array. This indicates its potential for combined wave-energy extraction and wave-field modification. Increasing the incident angle produces a more asymmetric wave field and reduces energy capture because of stronger shadowing of the downstream flaps. The interaction factor q decreases with increasing incident angle, indicating weaker constructive interference. Optimal energy capture is achieved when the lateral spacing between flaps is 1.0-1.5 times the flap width and the longitudinal spacing is approximately 0.4-0.6 times the incident wavelength. These findings provide practical guidance for the design of compact OWSC arrays that combine efficient wave-energy extraction with wave-field modification for nearby marine infrastructure, such as floating photovoltaic platforms.

Accurate prediction of wave overtopping at vegetated sloping dikes is essential for nature-based coastal defense design. This study presents laboratory experiments investigating the influence of a flexible vegetated foreshore on regular wave overtopping. The results indicate that, for a fixed dike height, increased crest freeboard enhances wave attenuation by submerged vegetation. Compared with unvegetated conditions, vegetation reduces both wave height and mean water level. Wave nonlinearity diminishes across vegetated foreshores, as evidenced by increasingly negative asymmetry — a characteristic of forward-leaning waves, marked by a rapid rise and slow fall. The impact of vegetation on overtopping discharge depends strongly on its physical characteristics: greater submergence, higher density, and larger relative width lead to more pronounced reductions. On average, vegetation reduces overtopping by 14.6

This research aims to explore the response of sea surface wave fields across mesoscale eddies under the influence of tropical cyclones (TCs) in the South China Sea, utilizing numerical simulations from the Finite-Volume Community Ocean Model (FVCOM) one-way coupling with the Simulating WAves Nearshore (SWAN) model. Four types of vertical coordinates were tested in FVCOM to improve the representation of upper-ocean variability under rapidly changing depths. The high-resolution hindcast sea surface temperature data was used for validation, revealing that the general vertical coordinate in FVCOM exhibited the most accurate results, showing a correlation (COR) of 0.90 and a root mean square error (RMSE) reaching 0.29 °C. Wave simulations were conducted using the SWAN model, which incorporated wave breaking influenced by depth and complex nonlinear interactions between waves. Based on 51 mesoscale eddies detected during five TCs from 2022 to 2024, the results reveal distinct modulation patterns. Regression analysis indicates a significant coupling among wind, waves, currents, and Eddy Kinetic Energy (EKE) within the eddies. While significant wave height (SWH) increases with prolonged TC forcing duration, TC translation speed shows no significant impact on SWH or EKE, suggesting that internal geostrophic adjustment plays a dominant role in eddy dynamics. Structurally, intense TC forcing was observed to disrupt pre-existing eddies and trigger the ageostrophic cold eddies characterized by high Rossby numbers (> 0.5) and low Richardson numbers (< 0.25). Furthermore, the modulation of TC-induced waves is identified as a spatial process involving steepening-induced dissipation at the periphery and refraction-induced redistribution at the edge. The warm eddy periphery acts as a low-pass filter, dissipating high-frequency energy early due to opposing currents. Combined with refractive effects, this mechanism leads to wave energy convergence in cold eddies versus divergence in warm eddies.

Abstract Globally, small-scale fishing communities are impacted by plastic debris accumulating in coastal waters. We studied the socioeconomic impact of marine plastic on fishers in the Mekong and Red River Deltas. Using a mixed methods design, we quantified the impacts of marine plastics through socioeconomic structured interviews with nearshore fishers (n = 199), post-hoc verification interviews (n = 94) and waste audits of debris in fishing nets (n = 282). The total cost of plastic pollution was calculated as ~3400 USD vessel-1 year-1, equivalent to 12% of the annual vessel revenue and 25% of the owner’s income. Fishers also experienced injuries and fatalities when dealing with plastic entanglement incidents at sea. Results highlighted a disproportionate and unequitable higher economic burden faced by lower-income fishers in the Mekong Delta compared to the Red River Delta. Our study found that incentive-based plastic collection at priority locations could reduce pollution while supporting sustainable livelihoods.

Since 2024, China’s 1mC Synthetic Aperture Radar (1mC-SAR) constellation, operating in Terrain Observation by Progressive Scans (TOPS) mode (40-m resolution and 600-km swath), has enabled daily typhoon observations over the western North Pacific. This study represents the first simultaneous retrieval of typhoon wind and wave parameters from 1mC-SAR observations. Unlike conventional methods relying on low-signal-to-noise-ratio (SNR) vertical-horizontal (VH) polarized normalized radar cross section (NRCS), we develop a Transformer-based joint wind–wave retrieval framework for typhoon conditions. A dataset of over 800,000 subscenes from 208 images of 28 typhoons during 2024–2025 was collocated with the reconstructed wind speed and Regional Ocean Modeling System–Simulating WAves Nearshore (ROMS-SWAN) hindcast wave fields. The Transformer uses a total of 19 image-derived intensity and spectral features to retrieve significant wave height (SWH) and dominant wave period (DWP). For wind speed retrieval, the retrieved wave parameters are used as auxiliary inputs, and wind–wave growth constraints are embedded into the loss function. The Transformer outperforms multilayer perceptron (MLP), Residual Network (ResNet), and extreme gradient boosting (XGBoost), achieving improved retrieval accuracy for SWH (RMSE = 0.60 m, r = -0.96), DWP (RMSE = 1.23 s, r = 0.79), and wind speed against Soil Moisture Active Passive (SMAP) observations (RMSE = 2.50 m/s, r = 0.92). Translation-induced asymmetry analysis shows strong wind–wave coupling over the left and back flanks of Northern Hemisphere typhoons (r = 0.46–0.71), whereas the right flank is weakly coupled with the back flank (r = 0.04–0.47). These results indicate that typhoon-generated waves exhibit more pronounced asymmetry than the wind field. Future work will focus on direct deep-learning-based retrieval of typhoon wave spectra from SAR imagery, which may further improve the understanding of complex sea states and wave propagation under extreme tropical cyclone conditions.

The main purpose of this study is to investigate the influence of mesoscale eddies on the distribution of phytoplankton chlorophyll-a (Chl-a) concentration in the East China Sea. Mesoscale eddies (radius > 20 km) were identified using sea current data from the Copernicus Marine Environment Monitoring Service (CMEMS) GLORYS12V1 reanalysis (0.08 degrees grid, 24-h intervals) via a vector geometry algorithm, and validated against sea level anomaly (SLA) assembled by Haiyang-2 (HY-2) altimeters and Chl-a from Haiyang-1C (HY-1C) Level-3 (L-3) (2023-2024). The CMEMS-based eddies show good consistency with SLA data for radii >100 km. Seasonal analysis of SLA/Eddy Kinetic Energy (EKE) and Chl-a cross-correlations indicate the strongest negative relationships in winter, suggesting that lower sea surface temperatures enhance phytoplankton sensitivity to eddy-induced dynamics. Results further reveal that mixed layer depth (MLD) strongly regulates Chl-a in cyclonic eddies (CEs), while its effect is weaker inside anticyclonic eddies (AEs) but more variable at their peripheries. Four interaction mechanisms were analysed - eddy stirring, eddy trapping, eddy-induced Ekman pumping and eddy intensification - classified as horizontal or vertical processes. Vertical mechanisms exhibit stronger links to Chl-a anomalies than horizontal ones. Notably, AEs exhibit peak Chl-a concentrations and vorticity in the upper-right quadrant, whereas CEs show maxima in the upper-left quadrant. Overall, the findings highlight eddy polarity, seasonality and vertical coupling as key drivers of phytoplankton distribution, underscoring the utility of high-resolution reanalysis for resolving ecological processes

Mass transport induced by group-forced subharmonic waves (infragravity waves) is investigated in the present study. A theoretical solution for subharmonic waves' kinematic contributions to fourth-order mass transport and drift velocity has been proposed for any depth and bandwidth for the first time. This model is validated using particle-tracking simulations driven by the flow field generated by the SWASH. The subharmonic-induced mass transport solution is a weighted sum of the subharmonic velocity variance spectrum and velocity skewness bispectrum due to the triad-difference interaction among two primary and one subharmonic components. For narrow-banded waves with long wave group relative to depth, the weightings become independent of spectral components, and the solution is recovered in the time domain. Two mechanisms contributing to mass transport were identified: a forward drift resulting from self-interaction similar to Stokes drift, and a depth-decaying backward drift induced by negative subharmonic velocity skewness due to the anti-phase coupling between subharmonics and wave groups. For narrow-banded waves the forward transport surpasses the backward transport for kh< 0.72, where k is the short wave wavenumber and h is the water depth. For other waves, the critical kh for this phenomenon decreases with increasing wave period and bed slope and decreasing bandwidth. At greater depths or steeper bed slopes, near-surface backward transport predominates over forward transport; at shallower depths or gentler slopes, forward transport is dominant throughout the water column. Although smaller than Stokes transport by short waves, the subharmonic wave-induced mass transport can affect the long-term trajectory of a floating and suspended particle. This study provides the first evidence and insight for the influences of group-forced subharmonics on vertically varying mass transport from the ocean surface to seabed in coastal environments.

Microplastics (MPs) and pesticides are widely distributed in sediments and can interact with each other to form complex pollutants, thereby altering their environmental impacts. However, it remains unclear whether this process affects the microbial degradation of MPs and pesticides. In this study, 90-day microcosm incubation experiment was conducted using polystyrene (PS), polyethylene (PE), polyethylene terephthalate (PET), polylactic acid (PLA), and atrazine (ATZ). MPs were recovered from the sediments after incubation. Metagenomic analysis was subsequently conducted to investigate the plastisphere microbes, while chemical characterization was performed to examine the surface structure of MPs. It was found that ATZ adsorption increased the mass loss of MPs by 47.37%, 139.44%, 174.67%, and 284.00% for PS, PE, PET, and PLA, respectively. Metagenomic binning analysis revealed that plastispheres enriched MPs and ATZ-degrading microbes, including Glycine, Aquabacterium, Azospirillum, and Pantoea, which carried degradation genes (PaaA, PaaK, PaaG, HSD17B4, alkR, ALDH, and aprE). All four types of MPs were degraded to acetyl-CoA by these functional microbes with distinct metabolic pathways. Acetyl-CoA and the ATZ-derived intermediates (hydroxyatrazine, cyanuric acid, and N-isopropylammelide) involved in the tricarboxylic acid cycle, facilitating the co-metabolism of MPs and ATZ. The study provides a new insight into the degradation mechanism of MPs in the presence of other emerging contaminants.

Microplastics (MPs) are emerging contaminants and accumulate in river sediments, which pose great threaten to the self-purification capacity of rivers by affecting the fate of dissolved organic matter (DOM). Although the impact of MPs on sediment DOM has already been confirmed, it remains unclear how differences in MP characteristics affect the chemical properties of DOM. Thus, this study selects 2 traditional MPs (polystyrene, PS; polypropylene, PP) and 1 biodegradable MPs (polylactic acid, PLA) to construct microcosm incubation system. We found a 3.17-fold increase in DOM concentrations within biodegradable MPs, while traditional MPs exhibited a marked reduction of 76 %-97 % in DOM humification. FTIR analysis indicated biodegradable MPs enhance degradation of carboxylic acids in DOM. Microbial analysis showed that MPs pollution significantly changed the composition and community of keystone microbes in sediment. Compared to PS (6) and PP (4), PLA (11) enriched more tolerant microbes in sediments and significantly reduced the abundance of functional genes associated with methanotrophy (23 %) and hydrocarbon_degradation (25 %). Our results further revealed that MPs affected DOM fractions by changing the composition and abundance of keystone microbes, thereby increasing the sediment DOM concentration. This study provided a new insight into the ecological risks of MPs in river ecosystems.

Complex turbulent flow structures are formed within and around box-type artificial reefs (ARs). This study utilizes Particle Image Velocimetry (PIV) and numerical simulation to investigate the flow field within and around ARs of various configurations, such as single- and dual-row arrays. It was found that a small space between reefs causes loading to concentrate on the first reef, while a large space enhances vortex intensity and reduces interference among reefs and promotes vortex development within individual reefs. An optimal space may enlarge the recirculation zone, increase vortex numbers and size, alter the flow distribution, and intensify turbulence, ultimately reshaping the flow characteristics at the reef array. The experimental data show that vortices within ARs attain their maximum strength at an overall reef length to height ratio (Lr/hr) of 3 and reef width to height ratio (Wr/hr) of 0.68. A further increase in Lr/hr weakens the dipole, while an increase in Wr/hr expands the area of high-vorticity and strong turbulence behind the stoss-face openings. These findings provide new insights for the optimum layout of artificial reefs for coastal defense design.

Nitrogen (N) is the primary driving factor of river eutrophication and a crucial nutrients in riverine systems. Microplastics (MPs) in urban rivers may affect N transformation in sediments. Although previous incubation experiments revealed the effect of MPs on N transformation, the relationship between MPs and N transformation in field conditions remain unclear. This study measured nitrogen concentrations, nitrogen transformation rates, the abundances and types of MPs, and keystone microbes in urban river sediments to reveal their interaction. The result indicated that MPs ranged from 200 to 1250 items/kg (dry weight) in urban river sediment, with polyethylene terephthalate (24.4 %), polyethylene (22.4 %), polystyrene (15.7 %), and polypropylene (10.2 %) being predominant. River sediment nitrification rates ranged from 0.05 to 4.19 mu mol N kg-1 h-1 , and denitrification and anaerobic ammonium oxidation rates were 3.30-206.76 and 0.07-3.99 nmol N g-1 h-1 , respectively. MPs pollution may promote nitrification, while inhibiting denitrification and anaerobic ammonium oxidation in sediment. Additionally, mathematical model confirmed that MPs pollutions directly changed the keystone microbes (Hyphomicrobium, Actinocorallia, Rhodoferax, Taylorella, and Magnetospirillum) and N transformation rates, thereby affecting N transformation in sediment. Compared to field experiments, incubation experiments might overestimate the impact of MPs on nitrification processes and underestimate their impact on denitrification processes. This study provided field evidence of the impacts of MPs on N transformation in urban rivers, informing the control of MPs and N pollutions in urban rivers.

Hospital wastewater contains high levels of antibiotics, metabolites, and antibiotic resistance genes (ARGs). "A/O + UV" is widely used for hospital wastewater treatment in China, but its effectiveness remains limited. Studies on pollutant removal under real conditions are insufficient. In this study, a non-targeted analysis was conducted using electrospray ionization Fourier-transform ion cyclotron resonance mass spectrometry (ESI FT-ICR-MS) combined with metagenomic techniques. The results showed that oxidation reactions dominated the integrated "A/O + UV disinfection" system. Yet it failed to completely degrade refractory organics. After treatment, the number of molecular formulas increased from 5191 to 7132, with higher unsaturation and aromaticity; phenolic compounds rose by 15.32 %. Eight antibiotics showed negative removal efficiencies. Sulfonamides, quinolones, tetracyclines, and macrolides were poorly degraded, producing numerous transformation byproducts with greater biological toxicity and stronger resistance to further degradation. Additionally, the composition of ARGs in the treated effluent became more diverse. These results indicate that current treatment technologies are inadequate, and associated risks may be underestimated. This research provides a new perspective for evaluating the effectiveness of hospital wastewater treatment technologies and improving relevant regulatory standards.

Wind field structure of tropical cyclone (TC) can be resolved by remotely sensed sensors operated at microwave frequency, i.e. synthetic aperture radar (SAR) and microwave radiometer. The main purpose of this study is to investigate the characteristics of TC wind observed by Sentinel-1 (S-1) and soil moisture active passive (SMAP) during over 100 TCs from 2016 to 2023. The swath coverage of CyclObs winds inverted from S-1 images is about 500 km with a spatial resolution of about 500 m, while the SMAP wind products have a swath coverage of 1000 km with spatial resolution of 0.25 degrees grids. Three TC parameters, geographic location of eye, maximum wind speed and radius of maximum wind speed, 34, 50, and 64 knot (kt) wind radii are estimated from CyclObs and SMAP winds. It is found that the distance between TC eyes derived from these two remote-sensed products and those from International Best Track Archive for Climate Stewardship (IBTrACS) reanalysis increases with central pressure increasing. Compared with IBTrACS data, the Root Mean Squared Error (RMSE) and Correlation Coefficient (COR) of maximum wind speed by CyclObs are 9.94 m s-1 and 0.63, whereas those by SMAP are 12.34 m s-1 and 0.51. In contrast, about 23 m RMSE of radius of maximum wind speed and about 0.7 COR is achieved from both CyclObs and SMAP winds. Here, the angle is defined as follows: 0 degrees-135 degrees clockwise relative with TC movement represents the right side, 135 degrees-225 degrees represents the back side, and 0 degrees-135 degrees counterclockwise represents the left side. The angle between the maximum wind velocity direction relative to TC translation direction (forward direction) is not correlated well with NHC maximum wind speed or NHC radius of maximum wind speed. Interestingly, as the radius of maximum wind speed increases, the angle in CyclObs wind increases at the back and left sides of TC centre, whereas the angle decreases at the right side. This behaviour is only observed at the left side in SMAP wind. [Traduit par la r & eacute;daction] La structure du champ de vent d'un cyclone tropical (CT) peut & ecirc;tre r & eacute;solue par des capteurs de t & eacute;l & eacute;d & eacute;tection fonctionnant & agrave; la fr & eacute;quence des micro-ondes, c'est-& agrave;-dire le radar & agrave; synth & egrave;se d'ouverture (RSO) et le radiom & egrave;tre & agrave; micro-ondes. L'objectif principal de cette & eacute;tude est d'examiner les caract & eacute;ristiques des vents des CT observ & eacute;s par Sentinel-1 (S-1) et l'humidit & eacute; du sol active passive (HSAP) pendant plus de 100 CT de 2016 & agrave; 2023. La couverture de la fauch & eacute;e des vents CyclObs invers & eacute;s & agrave; partir des images S-1 est d'environ 500 km avec une r & eacute;solution spatiale d'environ 500 m, tandis que les produits de vent HSAP ont une couverture de la fauch & eacute;e de 1000 km avec une r & eacute;solution spatiale de grilles de 0,25 degrees. Trois param & egrave;tres des CT, l'emplacement g & eacute;ographique de l'oe il, la vitesse maximale du vent et le rayon de la vitesse maximale du vent, les rayons de vent de 34, 50 et 64 n oe uds (kt) sont estim & eacute;s & agrave; partir des vents CyclObs et HSAP. On constate que les distances entre les yeux des CT d & eacute;riv & eacute;es de ces deux produits de t & eacute;l & eacute;d & eacute;tection et celles de la r & eacute;analyse IBTrACS (International Best Track Archive for Climate Stewardship) augmentent avec la hausse de la pression centrale. Par rapport aux donn & eacute;es IBTrACS, l'erreur quadratique moyenne (RMSE) et le coefficient de corr & eacute;lation de la vitesse maximale du vent obtenus par CyclObs sont de 9,94 m/s et 0,63, tandis que ceux obtenus par HSAP sont de 12,34 m/s et 0,51. En revanche, le rayon de la vitesse maximale du vent est d'environ 23 m pour la RMSE et le coefficient de corr & eacute;lation est d'environ 0,7 pour les vents CyclObs et HSAP. L'angle est d & eacute;fini comme suit: 0 degrees-135 degrees dans le sens des aiguilles d'une montre par rapport au mouvement du CT repr & eacute;sente le c & ocirc;t & eacute; droit, 135 degrees-225 degrees repr & eacute;sente le c & ocirc;t & eacute; arri & egrave;re, et 0 degrees-135 degrees dans le sens inverse des aiguilles d'une montre repr & eacute;sente le c & ocirc;t & eacute; gauche. L'angle entre la direction de la vitesse maximale du vent par rapport & agrave; la direction de translation du CT (direction avant) n'est pas bien corr & eacute;l & eacute; avec la vitesse maximale du vent du NHC ou le rayon de la vitesse maximale du vent du NHC. Il est int & eacute;ressant de noter qu'& agrave; mesure que le rayon de la vitesse maximale du vent augmente, l'angle dans le vent CyclObs augmente & agrave; l'arri & egrave;re et sur le c & ocirc;t & eacute; gauche du centre du CT, tandis que l'angle diminue sur le c & ocirc;t & eacute; droit. Ce comportement n'est observ & eacute; que sur le c & ocirc;t & eacute; gauche dans le vent HSAP.

Sargassum thunbergii is a dominant seaweed species in the intertidal zone along the coast of China. It provides various ecological services, such as primary productivity, marine carbon sequestration, and water purification. To investigate the population structure characteristics of Sargassum thunbergii, the Hegyi competition model was employed to quantify intraspecific competition within populations in the intertidal zone of Luhua Island, China. The results showed that the competition intensity decreased as a power function (y = 1.93x−0.89, R2 = 0.28) with increasing seaweed height. Intraspecific competition had minimal effects on seaweeds taller than 50 cm. Seaweeds at lower population levels exhibited more stable competition indices. Therefore, the model can reliably predict intraspecific competition intensity in Sargassum thunbergii. The sample circle method was applied to identify an optimal intraspecific competitive range of 50 cm for intertidal populations of Sargassum thunbergii. This study provides scientific guidance for seaweed spacing and rational harvesting during ecological restoration. Moreover, it offers valuable insight for conserving other macroalgae, such as Sargassum fusiforme, and restoring seaweed beds ecologically.

Extreme surface winds and wave heights of tropical cyclones (TCs)—pose serious threats to coastal community, infrastructure and environments. In recent decades, progress in numerical wave modeling has significantly enhanced the ability to reconstruct and predict wave behavior. This review offers an in-depth overview of TC-related wave modeling utilizing different computational schemes, with a special attention to WAVEWATCH III (WW3) and Simulating Waves Nearshore (SWAN). Due to the complex air–sea interactions during TCs, it is challenging to obtain accurate wind input data and optimize the parameterizations. Substantial spatial and temporal variations in water levels and current patterns occurs when coastal circulation is modulated by varying underwater topography. To explore their influence on waves, this study employs a coupled SWAN and Finite-Volume Community Ocean Model (FVCOM) modeling approach. Additionally, the interplay between wave and sea surface temperature (SST) is investigated by incorporating four key wave-induced forcing through breaking and non-breaking waves, radiation stress, and Stokes drift from WW3 into the Stony Brook Parallel Ocean Model (sbPOM). 20 TC events were analyzed to evaluate the performance of the selected parameterizations of external forcings in WW3 and SWAN. Among different nonlinear wave interaction schemes, Generalized Multiple Discrete Interaction Approximation (GMD) Discrete Interaction Approximation (DIA) and the computationally expensive Wave-Ray Tracing (WRT) A refined drag coefficient (Cd) equation, applied within an upgraded ST6 configuration, reduce significant wave height (SWH) prediction errors and the root mean square error (RMSE) for both SWAN and WW3 wave models. Surface currents and sea level variations notably altered the wave energy and wave height distributions, especially in the area with strong TC-induced oceanic current. Finally, coupling four wave-induced forcings into sbPOM enhanced SST simulation by refining heat flux estimates and promoting vertical mixing. Validation against Argo data showed that the updated sbPOM model achieved an RMSE as low as 1.39 m, with correlation coefficients nearing 0.9881.