Ocean Dynamics最新文献

{"title":"Improvement of drag coefficient parameterization of WAVEWATCH-III using remotely sensed products during tropical cyclones","authors":"Yuyi Hu, Weizeng Shao, Ying Xu, Qingping Zou, Xingwei Jiang","doi":"10.1007/s10236-024-01638-3","DOIUrl":"https://doi.org/10.1007/s10236-024-01638-3","url":null,"abstract":"<p>In this study, the parameterization of the drag coefficient is improved using remotely sensed wind and wave products during tropical cyclones (TCs) and implemented for wave simulation using a third-generation numeric model, namely, WAVEWATCH-III (WW3). The significant wave height and peak wavelength from SWIM(Surface Waves Investigation and Monitoring) measured wave spectra are collocated with wind speeds derived from the Haiyang-2 (HY-2) constellation, Soil Moisture Active–Passive (SMAP) radiometer, and Advanced Microwave Scanning Radiometer-2 (AMSR2) in 2019 − 2023. Cyclonic winds at a spatial resolution of 0.25° and intervals of 6 h are obtained by fusion remotely sensed winds from the HY-2 scatterometers and radiometers from SMAP and AMSR2. The parameterization of the drag coefficient during TCs is improved using a matching dataset for 100 TCs consisting of fusion winds and SWIM-measured wave spectra. The significant wave height (SWH) is simulated by WW3 using the optimized parameterization in the several input/dissipation source terms, i.e., ST2, ST3, ST4 and ST6. It is found that the accuracy of simulated SWH using optimized parameterization in switch ST2, ST3 and ST4 is worse than that using optimized parameterization in switch ST6. Moreover, taking two parameterizations in switch ST6 of WW3, validation against the measurements from altimeters and the SWH calculated by SWIM-measured wave spectrum during other 20 TCs yields a root mean square error (RMSE) of 0.60 m, and a correlation coefficient (COR) of 0.85 by optimized parameterization, which are better than the 0.68 m RMSE, and 0.80 COR obtained using existing parameterization. Furthermore, the variation in the bias (altimeter minus WW3) shows that the larger bias (&gt; 2 m) at wind speed &gt; 20 m/s or SWH &gt; 6 m is significantly improved using the optimized parameterization formula and fusion remotely sensed winds.</p>","PeriodicalId":19387,"journal":{"name":"Ocean Dynamics","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142227882","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Surface ocean conditions of the Arabian Sea using two different wind forcings in the regional ocean modelling system setup","authors":"Prabha Kushwaha, Vivek Kumar Pandey, Bijan Kumar Das","doi":"10.1007/s10236-024-01637-4","DOIUrl":"https://doi.org/10.1007/s10236-024-01637-4","url":null,"abstract":"<p>The study investigates the impact of two different wind forcings on the surface ocean conditions of the Arabian Sea (AS) using the Regional Ocean Modelling System (ROMS) simulations. The wind forcings used in the ROMS simulations are the climatological Comprehensive Ocean-Atmosphere Data Set (COADS) winds and the Quik Scatterometer (QuikSCAT) satellite sea-winds. These two wind forcings are implemented and evaluated individually to assess their respective influences on the surface ocean conditions such as temperature, salinity, currents, heat fluxes, fresh water flux and diffusivity over the AS. The QuikSCAT winds are seen stronger (up to 2 m/s) over the AS and the wind stress curl is higher (up to 1.5 × 10^− 7 N/m²) in the equatorial region as compared to the COADS winds. Both the simulations have replicated the overall pattern of the surface ocean conditions very well. The stronger QuikSCAT winds simulation has shown higher surface salinity (~ 2 psu) and freshwater fluxes compared to the weaker COADS winds simulation. Again, the strong winds from QuikSCAT have also increased the surface current (up to 0.2 m/s) and horizontal diffusivity in the southern and western boundary of the AS. The implementation of wind forcing provides valuable insights into the dynamics of the regional ocean system and its response to atmospheric conditions. Therefore, the implementation of COADS and QuikSCAT winds in the ROMS simulations will enhance our ability to accurately simulate and predict the behaviour of the surface ocean conditions of the AS.</p>","PeriodicalId":19387,"journal":{"name":"Ocean Dynamics","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142211148","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of tidal current potential in the Amapá’s inner continental shelf (Eastern Amazonia - Brazil)","authors":"Robert Willian Queiroz Farias, Maamar El -Robrini, Osvaldo Ronald Saavedra","doi":"10.1007/s10236-024-01636-5","DOIUrl":"https://doi.org/10.1007/s10236-024-01636-5","url":null,"abstract":"<p>This study addresses the global shift towards renewable energy due to the increasing demand driven by socioeconomic development. With finite fossil energy sources, there’s a growing interest in oceanic renewable energy, estimated at 76 million MW. The Amazon, with its significant potential, particularly from predictable tidal currents in estuaries, stands out. The Inner Continental Shelf of Amapá, influenced by factors like water discharge (5,7 × 10¹² m³.year^− 1) and trade winds (speed: 5–10 m.s^− 1) as well as Meso and Macrotidal, is a notable region. The paper focuses on hydrodynamic simulations considering different tidal scenarios and aims to assess the energy potential of tidal currents. Using the SisBaHiA two-dimensional hydrodynamic model, the study evaluates power density in key areas. The spring-neap cycle simulations identify promising zones in the Varador channel—upper section (tidal current velocity of 1,53 m.s^− 1– 1.835 W.m^− 2) and lower section (tidal current velocity of 1,12 m.s^− 1 – 720,03 W.m-²). Notably, the upper Varador channel near the Inferno ¨igarapé¨ (Maraca Island) exhibits greater energy density, highlighting its potential in both spring and neap cycles. This research contributes valuable insights into the renewable energy potential of tidal currents in the Amapá region, supporting sustainable energy development.</p>","PeriodicalId":19387,"journal":{"name":"Ocean Dynamics","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142210967","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Aggregation and transport of microplastics by a cold-core ring in the southern recirculation of the Kuroshio Extension: the role of mesoscale eddies on plastic debris distribution","authors":"Ryota Nakajima, Akira Nagano, Satoshi Osafune, Masashi Tsuchiya, Katsunori Fujikura","doi":"10.1007/s10236-024-01635-6","DOIUrl":"https://doi.org/10.1007/s10236-024-01635-6","url":null,"abstract":"<p>Mesoscale eddies – ocean vortices with spatial scales of tens to hundreds of kilometers and time scales of months to years – are among the most energetic forms of flow in the ocean, and may act as significant transporters of floating microplastics. Yet, shipboard observation has thus far not clarified the abundance and transport of microplastics in mesoscale eddies. We conducted floating microplastic surveys in an intense cyclonic mesoscale eddy with a large sea surface height depression (approximately 0.8 m), a so-called cold-core ring, in the Kuroshio Extension recirculation gyre (KERG) southeast of Japan. The concentration of microplastics within the eddy (460 × 10⁴ pieces/km²) was one or two orders of magnitude higher than in the adjacent oceanic waters, likely due to the acquisition of microplastics from the microplastic-rich Kuroshio Extension (KE) when detaching, as well as the horizontal entrainment of particles by the eddy. Our examination by using an assimilation product showed that most particles captured by the eddy remained within for several months while the eddy moved clockwise in the KERG. These results suggest that mesoscale eddies are of importance in the transportation and redistribution of microplastics on the ocean surface.</p>","PeriodicalId":19387,"journal":{"name":"Ocean Dynamics","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142211057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sea state contributions to thermosteric sea-level in high-resolution ocean-wave coupled simulations","authors":"Antonio Bonaduce, Nam Thanh Pham, Joanna Staneva, Sebastian Grayek, Roshin P. Raj, Øyvind Breivik","doi":"10.1007/s10236-024-01632-9","DOIUrl":"https://doi.org/10.1007/s10236-024-01632-9","url":null,"abstract":"<p>This study examines the impact of wave-induced processes (WIPs) in modulating thermosteric sea-level changes, highlighting the need to include these processes in future sea-level rise assessments and climate projections. The impact of wave-induced processes on thermosteric sea-level changes is investigated using coupled ocean-wave simulations. These simulations include the effects of Stokes-Coriolis forcing, sea-state dependent surface stress and energy fluxes, and wave-induced mixing. The experiments use a high-resolution configuration of the Geesthacht COAstal Model SysTem (GCOAST), covering the Northeast Atlantic, the North Sea and the Baltic Sea. The GCOAST system uses the Nucleus for European Modelling of the Ocean (NEMO) ocean model to account for wave-ocean interactions and ocean circulation. It is fully coupled with the WAM spectral wind wave model. The aim is to accurately quantify the sea state contribution to thermosteric sea level variability and trends over a 26-year period (1992–2017). The ability of wave-ocean coupled simulations to reveal the contribution of sea state to sea level variability and surge is demonstrated. It is clear that wave-induced processes (WIPs) play a significant role in sea surface dynamics, ocean mixing (mixed layer thickness) and modulation of air-sea fluxes (e.g. heat flux) in both winter (10–20%) and summer (10%), which in turn affect thermosteric sea level variability. The North Atlantic (in summer) and the Norwegian Trench (in winter) show significant contributions (40%) to the thermosteric sea-level variability due to wave-induced processes. The influence of WIPs on thermosteric sea level trends in the North Atlantic is up to the order of 1 mm yr-1 in both winter and summer, in the open ocean and at the shelf break. Smaller contributions are observed over the shelf areas of the North Sea. This study underscores the crucial role of WIPs in modulating sea-level changes and highlights the importance of including these processes in future sea-level rise assessments and climate projections.</p>","PeriodicalId":19387,"journal":{"name":"Ocean Dynamics","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142211149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of undular surges on a vertical wall","authors":"Feidong Zheng, Yaan Hu, Xueyi Li, Guiyang Liu","doi":"10.1007/s10236-024-01633-8","DOIUrl":"https://doi.org/10.1007/s10236-024-01633-8","url":null,"abstract":"<p>In the current study, the impact of undular surges on a vertical wall was experimentally investigated under complex base flow conditions where the velocity and flow depth were instantaneously varied. Undular surges of different wave types and with a wide spectrum of wave amplitudes were generated in a long horizontal wave tank by the filling operation of a downstream tank. Two characterized maximum wave pressures were observed during wave-wall interactions: pulsating wave pressure at an elevation close to the base flow surface and impact wave pressure occurring at a much higher elevation. It was found that the pulsating wave pressure could be solely estimated from the maximum wave run-up height, independently of the surge type. Moreover, the maximum wave load exerted by nonbreaking undular surges also depended on the maximum wave run-up height. Furthermore, the present results indicated that the influence of base flow conditions on undular surge-wall interactions were negligible. In addition, the breaking criterion of solitary waves in shallow water region could be used as an estimate of the transition in surge type, independently of the base flow conditions.</p>","PeriodicalId":19387,"journal":{"name":"Ocean Dynamics","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141863155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamics of the Polar Front in the southwestern area of Svalbard, Norway","authors":"Igor Shulman, Ewa Jarosz, Stephanie Cayula, E. Joseph Metzger","doi":"10.1007/s10236-024-01624-9","DOIUrl":"https://doi.org/10.1007/s10236-024-01624-9","url":null,"abstract":"<p>We have investigated the dynamics of the Polar Front (PF) in the southwestern area of Svalbard, where the dynamics are defined by the interaction between the Sørkapp Current (transporting cold and fresh Arctic-type water) and the West Spitsbergen Current (carrying the warmer and more saline Atlantic Water from the Norwegian Sea). Our approach was based on the global circulation model predictions. In accord with the model, the cold and fresher Arctic water masses originated from the eastern side of Svalbard and were flowing along the southern-most point of Svalbard into the southwestern area of Svalbard. This cold and fresher water was spreading and pushing warmer and more saline Atlantic water offshore. The model currents indicated that cold and fresher water masses were mostly transported northward along the south-western coast of Svalbard. In accord with the model and observed density profiles, the PF is a density compensated front with the density gradient mostly in the top 50-75 m. Presence of strong density gradients in the upper 50-75 m of the PF leads to the development of the submesoscale processes as surface frontogenesis and nonlinear Ekman transport. We found strong presence of surface frontogenesis at the PF in the model. The second submesoscale process, the nonlinear Ekman transport, is due to the forcing interaction. During the considered time frame, the winds were blowing mostly from the north-east to south-west across the PF, and therefore, the along-front wind component was very small, resulting in weak non-linear Ekman transport at the PF front.</p>","PeriodicalId":19387,"journal":{"name":"Ocean Dynamics","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141863261","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multi-sensor approach for chlorophyll-a monitoring in the coastal waters of Japan: a case study of the Yura Estuary","authors":"Shweta Yadav, Yoh Yamashita, Yosuke Alexandre Yamashiki","doi":"10.1007/s10236-024-01625-8","DOIUrl":"https://doi.org/10.1007/s10236-024-01625-8","url":null,"abstract":"<p>Estuaries are one of the most productive ecosystems in the world, supporting a variety of flora and fauna. Primary productivity by phytoplankton is a rich source of organic carbon, substantial for the aquatic food web. Monitoring phytoplankton (i.e., chlorophyll-a) is essential to assess the health of estuaries and other continental shelves subjected to constant anthropogenic stress (e.g., developmental activities). In this study, a three-endmember combination Spectral Decomposition Algorithm (SDA) was developed to estimate the phytoplankton in the micro-tidal Yura estuary of Japan using Landsat-8 (30 m), and Sentinel − 2A (10 m). The endmember water, phytoplankton, and submerged aquatic vegetation (SAV) yielded the best results with both the satellite sensors (R² &gt; 0.80) owing to the limited influence of non-phytoplankton suspended solids (NPSS) in the estuary. Chlorophyll-a was used as the proxy for phytoplankton. The estimated root mean square error (RMSE) was relatively higher in Landsat-8 (RMSE = 0.187 µg/L) than the Sentinel-2A (RMSE = 0.162 µg/L). The results were validated using the ground truth data of the Yura Estuary (26 sampling points). Furthermore, the results indicate low chlorophyll-a concentration in the Yura estuary (&lt; 2µg/L) except near the shorelines (~ 6 µg/L). A good fit (R² = 0.79) between observed chlorophyll-a and turbidity indicated phytoplankton-dominated turbidity in the tide-less estuary of Japan. The estimated maximum turbidity was 1.4 FTU using both sensors, suggesting a low anthropogenic influence on the Yura Estuary. The study demonstrates a successful application of the spectral decomposition algorithm (SDA) in the coastal waters which could further be used to assess the horizontal and temporal variability in phytoplankton in estuarine water.</p>","PeriodicalId":19387,"journal":{"name":"Ocean Dynamics","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141863259","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seasonal variation of chlorophyll-a in South Java over the past quarter-century","authors":"Yusuf Jati Wijaya, Ulung Jantama Wisha, Lilik Maslukah, Seto Windarto, Anindya Wirasatriya, Muhammad Zainuri","doi":"10.1007/s10236-024-01629-4","DOIUrl":"https://doi.org/10.1007/s10236-024-01629-4","url":null,"abstract":"<p>A comprehensive investigation was conducted to examine the variations in Chlorophyll-a (Chl-a) levels in the waters located to the south of Java Island throughout the past quarter-century. This study employs satellite data and reanalysis data gathered from multiple sources spanning the period between September 1997 and December 2022. The application of EOF analysis revealed that the most notable elevation in Chl-a contents took place during the seasons of SON (September, October, November) and DJF (December, January, February) in the years 1997/1998 and 2006/2007. It has been determined that this significant increase in Chl-a content in southern Java is contingent upon the fulfillment of a number of circumstances. These conditions are associated with climatic patterns in the Indian Ocean and Pacific Ocean. An elevation in Chl-a content was seen throughout the months of SON and DJF in instances where the Indian Ocean Dipole (IOD) had a positive phase. The concurrent occurrence of a powerful positive IOD and El Niño event in the Pacific Ocean is highly probable to result in a substantial elevation in Chl-a content in the southern region of Java. In addition, our findings indicate that the phenomenon of Kelvin wave upwelling significantly contributes to the elevation of Chl-a levels during the months of June, July, August (JJA), and SON.</p>","PeriodicalId":19387,"journal":{"name":"Ocean Dynamics","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141775926","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the application of Miyata-Choi-Camassa model to surface waves","authors":"Tianyu Zhang, Zhan Wang, Binbin Zhao, Masoud Hayatdavoodi, R. Cengiz Ertekin, Wenyang Duan","doi":"10.1007/s10236-024-01630-x","DOIUrl":"https://doi.org/10.1007/s10236-024-01630-x","url":null,"abstract":"<p>The strongly nonlinear Miyata-Choi-Camassa model, a two-layer internal-wave model that includes the free-surface effect (MCC-FS model), has shown excellent performance on simulating large-amplitude internal waves. In this study, we are interested in assessing whether the MCC-FS model can be applied to study problems involving surface waves, and how the model performs. For this purpose, we apply the two-layer MCC-FS model to a time-varying bottom to simulate surface water-waves by setting the same densities of the upper- and lower-fluid layers. Although densities of the upper and lower fluid layers are the same, it is found that the depth ratio of the two layers plays a remarkable role in the solution. By analyzing the linear dispersion relations of the MCC-FS model with three different depth ratios (<span>(varvec{h}_{varvec{1}}/varvec{h}_{varvec{2}}=varvec{1}/varvec{9})</span>, <span>(varvec{3}/varvec{7})</span> and <span>(varvec{5}/varvec{5})</span>, where <span>(varvec{h}_{varvec{1}})</span> and <span>(varvec{h}_{varvec{2}})</span> are the depths of the upper- and lower-fluid layers, respectively), we determine that the MCC-FS model with the depth ratio <span>(varvec{3}/varvec{7})</span> has the better performance on simulating surface water-waves. Under this configuration, we apply the MCC-FS model to simulate the surface solitary waves on a flat bottom, the solitary wave propagating over a submerged shelf and the surface water-waves generated by a bottom disturbance. By comparing with the laboratory measurements, the accuracy of the results provided by the MCC-FS model is validated.</p>","PeriodicalId":19387,"journal":{"name":"Ocean Dynamics","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141775931","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}