Journal of Geophysical Research-Oceans最新文献

{"title":"Size-Fractionated Photosynthetic Parameters and Their Controlling Factors in the Cosmonaut Sea, Southern Ocean","authors":"Wei Zhang,&nbsp;Qiang Hao,&nbsp;Jie Zhu,&nbsp;Shunan Cao,&nbsp;Jun Zhao,&nbsp;Dong Li,&nbsp;Changfeng Zhu,&nbsp;Qi Li","doi":"10.1029/2025JC022911","DOIUrl":"10.1029/2025JC022911","url":null,"abstract":"<p>The size structure of phytoplankton is a key determinant of oceanic energy transfer and biogeochemical cycling. Accurate estimation of primary productivity relies on photosynthetic parameters specific to different phytoplankton size classes. However, the broad size distribution of <i>Phaeocystis antarctica</i> poses challenges for pigment-based diagnostic approaches in resolving size-fractionated photosynthetic characteristics in the Southern Ocean. To overcome this limitation, we applied direct size-fractionated filtration to assess photosynthesis-irradiance (P–E) curves across the Cosmonaut Sea during the austral summer of 2022. Our results revealed that smaller phytoplankton exhibited greater photosynthetic efficiency especially under low-light and nutrient-depleted conditions. Primary productivity showed substantial spatial variation with the highest rates observed near the continental shelf. Incorporating phytoplankton size structure alongside environmental parameters markedly improved the estimation accuracy of photosynthetic physiological traits particularly for Nano + Pico phytoplankton. To this end, we developed and validated a size-fractionated model for photosynthetic parameters using in situ measurements. The model demonstrated high predictive performance with coefficients of determination (<i>r</i>²) of 0.96 for <i>P</i>^<i>B</i>_<i>m</i> (RMSD = 0.200 mg C [mg Chl <i>a</i>]⁻¹ hr⁻¹) and 0.97 for <i>α</i> (RMSD = 0.001 mg C [mg Chl <i>a</i>]⁻¹ hr⁻¹ [μmol quanta m⁻² s⁻¹]⁻¹). The model results underscore the importance of incorporating size-specific physiological traits into photosynthetic parameter models to enhance the predictive accuracy of primary production in polar marine ecosystems.</p>","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 9","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144929712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of the Spatiotemporal Distribution of Shear Stress and Bedload Flux Within a Mobile, Rippled Bed","authors":"Savannah R. DeVoe,&nbsp;Meagan E. Wengrove,&nbsp;Diane L. Foster,&nbsp;Daniel S. Hagan","doi":"10.1029/2025JC022369","DOIUrl":"10.1029/2025JC022369","url":null,"abstract":"<p>Mobile sediment layer dynamics and the distribution of shear stress within mobile fluid-sediment mixtures are not well understood, particularly for oscillatory flows over rippled boundaries. This article provides insight into bed shear stress at and within a mobile, rippled bedform at high spatiotemporal resolution for the purpose of improving estimates of bedload transport. Data from a coupled Large Eddy Simulation (LES) and Discrete Particle Model (DPM) is used to characterize the spatiotemporal distribution of shear stress within the bed. Estimates of stress within the mobile layer are obtained using a new momentum integral method expression for oscillatory flow over mobile, porous, non-planar boundaries that makes no a priori assumptions about the boundary layer shape. Shear stress within the mobile layer and the resulting bedload flux show a strong response to the near-bed flow. Two local maxima occur within the mobile layer shear stress distribution during each half-oscillation period that coincide with near-bed fluid acceleration and the formation of a lee-side ripple vortex. The depth-averaged mobile layer Shields parameter, <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mrow>\u0000 <msub>\u0000 <mover>\u0000 <mi>θ</mi>\u0000 <mo>˜</mo>\u0000 </mover>\u0000 <mrow>\u0000 <mi>M</mi>\u0000 <mi>L</mi>\u0000 </mrow>\u0000 </msub>\u0000 </mrow>\u0000 </mrow>\u0000 <annotation> ${widetilde{theta }}_{ML}$</annotation>\u0000 </semantics></math>, obtained by depth-averaging across the mobile layer of grains, is approximately one-half the magnitude of the Shields parameter at the top of the mobile layer, and may serve as a better indicator of bedform motion for rippled beds subjected to oscillatory flow. Findings highlight the implications of the assumed bed elevation on the resulting magnitude and direction of estimated shear stress, as well as discrepancies in the magnitude and phase of bedload flux estimated with existing semi-empirical formulae.</p>","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 9","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2025JC022369","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144927681","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Impact of Antarctic Sea Ice on Southern Ocean Water Mass Transformation in Coupled Climate Models","authors":"Zijin Chen,&nbsp;William Hobbs,&nbsp;Zanna Chase,&nbsp;Jan Zika","doi":"10.1029/2025JC022445","DOIUrl":"10.1029/2025JC022445","url":null,"abstract":"<p>The Southern Ocean is a critical heat and carbon sink due to the interaction between the atmosphere and deep ocean that occurs there. Antarctic sea ice is essential for maintaining this interaction by transforming ventilated deep-water into both denser and lighter water masses. However, the representation of sea ice in climate models is variable, and its impact on water mass transformation remains unclear. We evaluate the contribution of sea ice to surface water mass transformation in the Southern Ocean in 16 models from Phase 6 of the Coupled Model Intercomparison Project (CMIP6). We find that sea ice redistributes freshwater from the Antarctic coast to offshore, acting as a pump, driving 10.2 <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>±</mo>\u0000 </mrow>\u0000 <annotation> $pm $</annotation>\u0000 </semantics></math> 8.8 Sv of deep-water ventilation across the ensemble. Variations in ventilation between models are driven by biases both in sea ice production and the ocean state. Firstly, the models' sea ice biases directly affect the net freshwater flux into the ocean. Secondly, the impact of surface freshwater flux on water mass transformation depends also on the ocean's surface density and salinity, so that biases in the model ocean state also play a role. We find that heat fluxes can partially compensate for variations in the sea ice contribution, so that models with lower sea-ice driven ventilation have higher heat flux driven ventilation. Therefore, sea ice is an important but not the sole determinant of the interaction between the atmosphere and deep ocean in models of the Southern Ocean.</p>","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 9","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2025JC022445","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144927682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In Situ Observations of Tide-Dominated Fluid-Mud Generation and Transport on the Central Jiangsu Tidal Flat","authors":"Yun Peng,&nbsp;Qian Yu,&nbsp;Jianhua Gao,&nbsp;Yunwei Wang,&nbsp;Shu Gao","doi":"10.1029/2025JC022783","DOIUrl":"10.1029/2025JC022783","url":null,"abstract":"<p>Fluid mud (FM), a near-bed layer of high suspended sediment concentration, can be transported offshore in the form of gravity flow under the support of waves and currents, playing a critical role in sediment transport and geomorphological evolution. Wave-supported FM has been extensively studied, whereas research on the transport processes of tide-dominated FM remains insufficient. Here, we conducted four field campaigns on the central Jiangsu tidal flats, revealing that FM events occur frequently during winter, spring, and summer. The FM can be transported offshore as a gravity flow, with gravity-driven velocities ranging from 0.01 to 0.06 m s⁻¹. <i>In situ</i> measurements combined with theoretical modeling indicate that FM generation and transport in the central Jiangsu tidal flats are tide-dominated. On a tidal cycle scale, the tide-dominated FM pattern was divided into four stages. Stage I: during flood tides, fine sediment is transported landward from offshore waters to the tidal flat; Stage II: sediment settles from the overlying water column to the bed during flood slack tide, leading to the formation of FM; Stage III: ebb currents facilitate the downslope transport of FM as a gravity flow; Stage IV: ebb currents disperse the sediment within the FM layer, ultimately causing its dissipation. The tide-dominated FM presented in this study significantly differs from wave-supported FM, advancing the understanding of sediment dynamics on tidal flats and underscoring the importance of observing tide-dominated FM in similar coastal environments globally.</p>","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 9","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144923525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Melt Pond Nutrient Dynamics and Their Relationship With Melt Pond Bottom Ice in the Central Arctic Ocean","authors":"Ryota Akino,&nbsp;Daiki Nomura,&nbsp;Alison Webb,&nbsp;Yuhong Li,&nbsp;Manuel Dall'osto,&nbsp;Katrin Schmidt,&nbsp;Elise S. Droste,&nbsp;Emelia J. Chamberlain,&nbsp;Nikolai Kolabutin,&nbsp;Egor Shimanchuk,&nbsp;Ruzica Dadic,&nbsp;Allison A. Fong,&nbsp;Sinhué Torres-Valdés,&nbsp;Clara J. M. Hoppe,&nbsp;Laura Whitmore,&nbsp;Hanno Meyer,&nbsp;Yuichi Nosaka,&nbsp;Jun Inoue,&nbsp;Oliver Müller,&nbsp;Bruno Delille","doi":"10.1029/2024JC022018","DOIUrl":"10.1029/2024JC022018","url":null,"abstract":"<p>Melt pond is a common and important feature of the Arctic in the summer season. Melt ponds provide unique microbial habitats with high light availability, which can promote photosynthesis. Therefore, melt ponds play an important role for nutrient cycling at the ice-ocean interface. However, the changes in nutrient dynamics in and under the sea ice resulting from melt pond formation are poorly understood. To elucidate melt pond nutrient (NO₃⁻, NO₂⁻, NH₄⁺, PO₄³⁻, and Si(OH)₄) dynamics and their relationship with the melt pond bottom ice, which is sea ice right beneath the floor of a melt pond, in the Central Arctic Ocean during late summer, melt pond water and bottom sea-ice samples were collected during the MOSAiC Expedition (2019–2020). Comparison with the dilution line based on winter surface seawater, which is a source of sea ice, suggest that nutrients in the melt ponds are consumed by algae or other organisms, and then remineralized at the pond bottom. Nutrients then percolated downward through the porous bottom ice. Melt pond water was completely exchanged with surrounding seawater (lead or under-ice seawater) and snow derived water. If the surrounding seawater and snow are rich in nutrients, the exchange promotes photosynthesis within the melt pond water and can enhance nutrient accumulation within the pond bottom ice.</p>","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 9","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2024JC022018","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144918673","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unraveling Both Community Divergences and Driving Factors of Pelagic Microbial Food Web in Different Water Masses of the Eastern Arctic Ocean","authors":"Chaofeng Wang,&nbsp;Guangfu Luo,&nbsp;Xiaoyu Wang,&nbsp;Zhiqiang Xu,&nbsp;Musheng Lan,&nbsp;Junjian Wang,&nbsp;Denggani Liang,&nbsp;Yifei Fan,&nbsp;Wenfei Zhang,&nbsp;Meiping Feng,&nbsp;Li Zhao,&nbsp;Wuchang Zhang","doi":"10.1029/2025JC022793","DOIUrl":"10.1029/2025JC022793","url":null,"abstract":"<p>Microbial food webs (MFWs) constitute the foundational framework of marine pelagic ecosystems, yet their community structure, trophic interactions, and associated abiotic driving factors remain inadequately characterized in the Arctic Ocean. To fill this gap, we conducted a comprehensive ship-based survey during summer 2020 to investigate three MFW trophic levels (picoplankton—Pico, nanoplankton—Nano, microzooplankton—Micro) from surface to 500 m layers. Each MFW component displayed a consistent subsurface peak in its vertical distribution. Additionally, five distinct water masses were identified, and each harboring a distinctive MFW composition. Within this framework, heterotrophic prokaryotes dominated numerically across all water masses, and Pacific-origin <i>Synechococcus</i> emerged as a valuable bioindicator for tracking Arctic environmental fluctuations. Notably, trophic-level abundance ratios conformed to a pyramidal structure, spanning five and two orders of magnitude for Pico:Micro (3.5–12.8 × 10⁵:1) and Nano:Micro (1.6–10.0 × 10²:1), respectively. Unlike biomass ratios, for which spanned one and zero order in Pico:Micro (0.4–1.2 × 10¹:1) and Nano:Micro (0.8–2.6:1), respectively. Concerning biotic-abiotic interactions, both abundance and biomass of each MFW component demonstrated a linear increase with both temperature and Chl <i>a</i> concentrations in Pacific Summer Water. Therein, picoeukaryotes exhibited the steepest slope revealed that their heightened sensitivity to temperature changes. Furthermore, the driving factors for MFW trophic linkages varied significantly among water masses, and the bottom‒up control (resource availability) predominating microzooplankton composition. This study upon trophic-level interaction establishes a baseline for quantifying and predicting how future environmental changes may affect pelagic MFWs in polar marine ecosystems.</p>","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 9","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144918815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Distribution of Plastics of Various Sizes and Densities in the Global Ocean From a 3D Eulerian Model","authors":"Zih-En Tseng,&nbsp;Yue Wu,&nbsp;Dimitris Menemenlis,&nbsp;Guangyao Wang,&nbsp;Chris Ruf,&nbsp;Yulin Pan","doi":"10.1029/2025JC023272","DOIUrl":"10.1029/2025JC023272","url":null,"abstract":"<p>We study the global transport and distribution of microplastics (MPs) using a three-dimensional Eulerian model. For the first time, the effects of both particle size and density are accounted for, influencing the vertical transport of MPs, and leading to an advanced understanding of their global distribution. Our simulations reveal two key findings: Only particles with low density and sufficiently large size (e.g., density 900 kg <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msup>\u0000 <mi>m</mi>\u0000 <mrow>\u0000 <mo>−</mo>\u0000 <mn>3</mn>\u0000 </mrow>\u0000 </msup>\u0000 </mrow>\u0000 <annotation> ${mathrm{m}}^{-3}$</annotation>\u0000 </semantics></math> and size <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>≳</mo>\u0000 </mrow>\u0000 <annotation> $gtrsim $</annotation>\u0000 </semantics></math>10 <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>μ</mi>\u0000 </mrow>\u0000 <annotation> ${upmu }$</annotation>\u0000 </semantics></math>m) aggregate in the five subtropical gyres that were identified in previous studies. In contrast, sufficiently small particles (<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>≲</mo>\u0000 </mrow>\u0000 <annotation> $lesssim $</annotation>\u0000 </semantics></math>1 <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>μ</mi>\u0000 </mrow>\u0000 <annotation> ${upmu }$</annotation>\u0000 </semantics></math>m), regardless of their density, behave like neutrally buoyant particles and can penetrate down to 1 km deep into the ocean. In addition, we observe a seasonal variation in the surface concentration of positively buoyant MPs—higher in summer and lower in winter—which reasonably agrees with the satellite observations made by the Cyclone Global Navigation Satellite System (CYGNSS) in terms of the phase of the variation. A quantitative analysis shows that the seasonal variation in the surface particle concentration correlates well globally with the variation in mixed layer depth. We attribute this correlation to the vertical stretching/squeezing effect of the seasonally varying mixed layer, where the total amount of positively buoyant particles is conserved.</p>","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 9","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2025JC023272","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144918816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of Ice Dissipation Parameterizations in Spectral Ocean Wave Model WAVEWATCH III: An Intercomparison Analysis","authors":"Fabien Montiel,&nbsp;Martin Forbes,&nbsp;Emilio Echevarria,&nbsp;Henrique Rapizo,&nbsp;Carlo Gamble","doi":"10.1029/2024JC022113","DOIUrl":"10.1029/2024JC022113","url":null,"abstract":"<p>Ocean wave activity in polar seas is intensifying, so that modeling waves in ice-covered oceans accurately is critical for navigational safety and forecasting the response of the declining sea ice. WAVEWATCH III (WW3) has emerged as the leading spectral wave model for high-latitude regions in recent years, having incorporated an extensive suite of 14 ice-induced wave-damping parameterizations. A set of WW3 hindcast simulations of the wave event observed during the 2017 PIPERS wave buoy deployment in the Ross Sea is conducted to assess the performance of all ice-damping parameterizations and identify consistent biases. Colocated spectra obtained from each WW3 hindcast and buoy measurements are analyzed and compared in relation to wave and ice conditions. It is found that 9 of the 14 parameterizations are able to reproduce large wave events accurately for lower ice concentrations. WW3 consistently overestimates significant wave height and underestimates the mean wave period at high ice concentrations. Our findings suggest WW3 does not sufficiently damp the mid- to high-frequency tail of the wave spectrum in the wave and ice conditions encountered during the PIPERS deployment.</p>","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 9","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2024JC022113","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144915138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Southern Ocean 3D Eddy Diagnostics Derived From SWOT","authors":"Elisa Carli,&nbsp;Yann-Treden Tranchant,&nbsp;Lia Siegelman,&nbsp;Florian Le Guillou,&nbsp;Rosemary Morrow,&nbsp;Maxime Ballarotta,&nbsp;Oscar Vergara","doi":"10.1029/2024JC022307","DOIUrl":"10.1029/2024JC022307","url":null,"abstract":"&lt;p&gt;Observations of sea surface height (SSH) from the Surface Water and Ocean Topography (SWOT) satellite have demonstrated remarkable potential for resolving mesoscale and submesoscale ocean features, which are crucial for deriving vertical velocities, a key variable for understanding the transport of heat, carbon, and nutrients between the ocean surface and interior. In the mesoscale energetic region south of Tasmania, we evaluate the accuracy of SWOT small-scale observations using high-resolution (&lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;∼&lt;/mo&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${sim} $&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;8 km) in situ observations of surface tracer fields and vertical temperature. Surface features derived from SWOT align with subsurface horizontal temperature gradients derived from the in situ measurements. These fine scales (&lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;&lt;&lt;/mo&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${&lt; } $&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;100 km) reveal dynamic phenomena, such as a sudden front deflection near the Macquarie Ridge, obscured in conventional low-resolution products. We then quantify the contributions of these small scales to the currents' energy and shape, compared to the larger mesoscales (&lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;&gt;&lt;/mo&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${ &gt;} $&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;100 km) observable with traditional nadir-looking altimetry. Although larger scales predominantly influence the geostrophic velocity, smaller scales contribute significantly to current stretching and straining, showing up to threefold stronger strain and tenfold stronger vorticity than larger scales in a few hotspots. Finally, we investigate the contribution of these small scales to the vertical velocities &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;(&lt;/mo&gt;\u0000 &lt;mi&gt;w&lt;/mi&gt;\u0000 &lt;mo&gt;)&lt;/mo&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; $(w)$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; down to 1,000 m that are reconstructed using effective surface Quasi-Geostrophic theory. SWOT-derived &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;w&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; $w$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; exhibit twice the amplitude","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 9","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2024JC022307","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144914894","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Insight on the Coastal Response to Combined Tides, Storm Surges, and Surface Waves in a Macrotidal Bay From Real-Time Predictions","authors":"Laura L. Swatridge,&nbsp;Ryan P. Mulligan,&nbsp;Leon Boegman,&nbsp;Shiliang Shan,&nbsp;Enda Murphy","doi":"10.1029/2024JC022076","DOIUrl":"10.1029/2024JC022076","url":null,"abstract":"<p>Hazardous sea surface conditions can develop during storm events, when wind-generated waves and storm surges coincide with high astronomical tides. For better understanding of these conditions, a novel and computationally efficient real-time forecast model (COASTLINES-BoF) was developed for a macrotidal bay that is exposed to wind waves, the Bay of Fundy in Atlantic Canada. This forecasting system simulates the combined effects of tides, storm surge, and waves. Spatiotemporally varying meteorological forecasts drive the model, with water levels and ocean waves applied at the open boundary in the Atlantic Ocean, implemented with input from large-scale ocean forecast models. Analysis of the real-time performance indicates that the model accurately predicts total water levels compared to observations. Modeled significant wave heights agree with buoy observations and altimeter data. During Post-tropical Hurricane Fiona in 2022, a peak water level residual (combined storm surge and water level change driven by wave-current interactions) of over 0.9 m was forecast in the upper Bay of Fundy. Sensitivity analysis indicates that 0.6 m of the water level increase resulted from wind and pressure effects, and an additional 0.3 m water level contribution is a result of wave-current interaction. The high accuracy, use of open data to drive and validate the model, and relatively low computational demand make this approach a useful way to gain insight into the coastal response to a wide range of conditions. This method can be applied to predict marine environmental conditions in other coastal regions.</p>","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 9","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2024JC022076","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144897744","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}