Journal of Geophysical Research-Oceans最新文献

{"title":"An Intermediate Current in Tropical North Pacific Observed by Moored Current Meters","authors":"Xiaoluan Yan,&nbsp;Linlin Zhang,&nbsp;Yuchao Hui,&nbsp;Fan Wang","doi":"10.1029/2024JC021960","DOIUrl":"https://doi.org/10.1029/2024JC021960","url":null,"abstract":"<p>Six years of current meter observation from a subsurface mooring at 130°E, 8.5°N captured an eastward flow below the North Equatorial Undercurrent (NEUC) between 1,500 and 3,000 m. This flow, named Lower-NEUC, has mean velocity of 0.73 ± 0.08 cm/s and 1.05 ± 0.08 cm/s at 2,000 and 2,500 m, respectively. Its spatial distribution is studied using Argo absolute geostrophic velocity data and ocean reanalysis. In the northwestern Pacific, Lower-NEUC shifts poleward with increasing longitude and is wider in Argo absolute geostrophic velocity data (around 300 km) and narrower in reanalysis (around 150 km). Vertically, the core of Lower-NEUC lies mostly between 27.5 and 27.6<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>σ</mi>\u0000 <mi>θ</mi>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${sigma }_{theta }$</annotation>\u0000 </semantics></math> in reanalysis, shallower compared to mooring observation. Reanalysis data shows L-NEUC's generation is connected to deep eddies. After proving that L-NEUC is not a result of averaging west-translating eddies, we showed that L-NEUC is generated by eddy potential vorticity flux convergence.</p>","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143554524","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":"Hurricane-Driven Transport of Bermuda Reef Carbonate Platform Sediments to the Deep Ocean","authors":"R. Pedrosa-Pamies,&nbsp;M. H. Conte,&nbsp;J. C. Weber,&nbsp;A. J. Andersson","doi":"10.1029/2023JC020500","DOIUrl":"https://doi.org/10.1029/2023JC020500","url":null,"abstract":"<p>Tropical cyclones erode and remobilize coastal sediments but their impact on the deep ocean remains unclear. Hurricane-driven transport of carbonates and associated materials from reef carbonate platforms to the deep ocean has important implications for carbon storage, deep ecosystems and ocean chemistry as carbonate platform reef-sourced aragonite and high-Mg calcite (HMC) may dissolve and contribute to deep water total alkalinity. Here we describe two hurricane-driven resuspension events where deep sediment plumes from the Bermuda Pedestal (NW Atlantic) were advected to deep waters surrounding the Oceanic Flux Program (OFP) mooring site, ∼75 km southeast of Bermuda. Hurricanes Fabian (Cat. 3, 2003) and Igor (Cat. 1, 2010) generated large near-inertial waves propagating to &gt;750 m depths, leading to widespread sediment resuspension from the Pedestal. Following Fabian, carbonate fluxes at the OFP site increased 15-fold, 32-fold, and 6-fold at 500, 1,500 and 3,200 m, respectively, with the 1,500 m flux equivalent to the total annual carbonate flux. OFP traps similarly captured a large detrital carbonate plume following Igor; here, the plume was shallower and persisted longer. Microscopy, geochemistry, and mineralogy confirmed that both plumes consisted of fine-grained shallow-water detrital carbonates alongside other materials accumulated on the Pedestal including phosphorus, lithogenic, authigenic, and pollutant elements. Clay-sized particles (&lt;4 μm) in both plumes exhibited high contents of lithogenic and authigenic elements, and Zn, Cd, and V, facilitating their transport over long distances. Grain-size, elemental, and lipid composition indicated that plumes intercepted at different depths originated from different source areas on the Pedestal.</p>","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143554522","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":"The Impact of Anomalous Biomass Burning on Phytoplankton and Surface Ocean Carbon Pool in the Indo-China Peninsula","authors":"Wenjing Liu,&nbsp;Wencai Wang","doi":"10.1029/2024JC022070","DOIUrl":"https://doi.org/10.1029/2024JC022070","url":null,"abstract":"<p>The ocean carbon sink plays a pivotal role in absorbing carbon dioxide and combating climate change. By utilizing satellite data, this study identified an exceptionally severe biomass burning event in the Indo-China Peninsula on 31 March 2020. This incident engulfed most of the island, with a total of 3,550 fires, representing the highest number of fire points from 2015 to 2023. Furthermore, this abnormal burning released 5.71 × 10⁹ kg of carbon dioxide in the dense fire area, accompanied by smoke aerosols that were rich in nutrients and carbon. These smoke aerosols were transported to the western Pacific Ocean by the subtropical high boundary stream. Upon deposition into the ocean, the smoke aerosols triggered a maximum increase of 314% in chlorophyll a concentration, as compared to the average for April 2020. This significant stimulation of phytoplankton growth indirectly contributed to the expansion of the surface ocean carbon pool. During their deposition, carbon export through the biological pump mechanism was 3.13 ± 1.27 × 10⁸ kg. Although anomalous wildfires emitted more smoke aerosols, there was no significant increase in ocean carbon export. Ultimately, the response of the surface ocean carbon pool to the influence of smoke aerosols partially offset about 20.06 ± 7.51% of the carbon emissions. Additionally, smoke aerosols directly increased the surface ocean carbon pool by 2.64 × 10⁷ kg through their own carbon deposition mechanism. Our study demonstrated that the ocean's capacity for carbon uptake is constrained. The carbon dioxide emissions from anomalous biomass burning events significantly surpass those that the ocean can effectively assimilate.</p>","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143554523","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":"Characterizing the Central Structure of a Mesoscale Eddy-Ring Dipole in the Mozambique Channel From In Situ Observations","authors":"Pierrick Penven,&nbsp;Jean-Francois Ternon,&nbsp;Margaux Noyon,&nbsp;Steven Herbette,&nbsp;Gildas Cambon,&nbsp;Caroline Comby,&nbsp;Pierre L’Hégaret,&nbsp;Bernardino S. Malauene,&nbsp;Claire Ménesguen,&nbsp;Fialho Nehama,&nbsp;Gustav Rauntenbach,&nbsp;Yula Rufino,&nbsp;Floriane Sudre","doi":"10.1029/2024JC021913","DOIUrl":"https://doi.org/10.1029/2024JC021913","url":null,"abstract":"<p>During the RESILIENCE cruise aboard the R/V Marion Dufresne II (April 19–24 May 2022), a high-resolution in situ observation campaign investigated a mesoscale dipole in the Mozambique Channel, composed of a large anticyclonic ring and a cyclonic eddy. Using an innovative adaptive sampling strategy to track its movement, we employed continuous observing systems, including a Moving Vessel Profiler and Acoustic Doppler Current Profilers, to capture high-resolution vertical sections. The results revealed a distinct dipolar structure: The 250 km-wide anticyclonic ring featured low chlorophyll and homogeneous waters, while the smaller cyclonic eddy exhibited higher chlorophyll concentrations and pronounced salinity variations. These include patches, vertically stacked layers, and filaments, reflecting a mix of contrasted water masses from the southern Mozambique Channel and the Sofala Bank. A central jet between the eddies exhibited horizontal velocities up to 130 cm <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msup>\u0000 <mi>s</mi>\u0000 <mrow>\u0000 <mo>−</mo>\u0000 <mn>1</mn>\u0000 </mrow>\u0000 </msup>\u0000 </mrow>\u0000 <annotation> ${mathrm{s}}^{-1}$</annotation>\u0000 </semantics></math>, facilitating significant offshore transport exceeding 10 Sverdrups in the upper 250 m and emphasizing the dipole's role in eastward water movement. Vertical velocities, derived from the Quasi-Geostrophic Omega equation, highlighted the influence of smaller-scale structures in driving vertical motions, reaching 40 m <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msup>\u0000 <mtext>day</mtext>\u0000 <mrow>\u0000 <mo>−</mo>\u0000 <mn>1</mn>\u0000 </mrow>\u0000 </msup>\u0000 </mrow>\u0000 <annotation> ${text{day}}^{-1}$</annotation>\u0000 </semantics></math> at depth. Lagrangian particle trajectories revealed the dipole's spiraling structure and its connectivity to coastal waters. These findings show that Mozambique Eddy-Ring Dipoles efficiently transport properties from the continental shelf to the open ocean, enhancing regional ecosystem connectivity. This work provides new insights into their biogeochemical, biological and ecological significance, challenging traditional cyclonic/anticyclonic eddy paradigms, and setting the foundation for future studies on mesoscale dipoles in the region.</p>","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JC021913","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143530520","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":"Processes That Influence Bottom Temperatures in the California Current System","authors":"M. A. Alexander,&nbsp;J. D. Scott,&nbsp;M. G. Jacox,&nbsp;D. J. Amaya,&nbsp;L. M. Wilczynski","doi":"10.1029/2024JC021886","DOIUrl":"https://doi.org/10.1029/2024JC021886","url":null,"abstract":"<p>Bottom water temperature (BWT) strongly influences marine organisms in coastal waters. Although subsurface observations are limited, the recent development of high-resolution reanalyses enables a detailed three-dimensional view of the ocean, including on the continental shelf. Here, we use the GLORYS 1/12° (∼9 km) reanalysis during 1993–2019 to examine processes that influence BWT anomalies on the shelf (≤400 m bottom depth) off the West Coast of Baja California and the contiguous US. We examine the relationship between BWT anomalies and other ocean variables, including mixed layer depth (MLD), thermocline depth (TD), thermocline and bottom temperature gradients, and bottom currents. The strongest and most spatially coherent connections with BWT anomalies occur for MLD during winter and TD in summer. BWT anomalies are also correlated with the local sea surface height (SSH) anomalies with maxima at 2–5 days lag. On subseasonal timescales, the lag of the maximum coherence of SSH at the southern tip of Baja California with both SSH and BWT increases northwards, consistent with propagating coastally trapped waves (CTWs), although the BWT anomalies decrease with latitude. Like SST and SSH, BWT anomalies are coherent along the entire West Coast on interannual timescales, reflecting ENSO's influence on the northeast Pacific. In contrast to CTWs, wind-driven upwelling's impact on BWT anomalies increases with latitude. Regional ocean model experiments confirm the GLORYS analysis and highlight the importance of remote wind-driven effects, in addition to local winds, on BWT in the northern part of the domain.</p>","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JC021886","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143530424","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":"Groundwater Hydrodynamic Oscillations From Swash With Transparent Sand (GHOSTS)","authors":"Delaney M. Benoit,&nbsp;Marie-Pierre C. Delisle,&nbsp;Greg Siemens,&nbsp;Britt Raubenheimer,&nbsp;Steve Elgar,&nbsp;Ryan P. Mulligan","doi":"10.1029/2024JC021293","DOIUrl":"https://doi.org/10.1029/2024JC021293","url":null,"abstract":"<p>Interactions between surface flows and groundwater in beaches can influence erosion and accretion, wave overtopping, groundwater levels and salinization, and transport of nutrients and pollutants. Laboratory experiments using transparent crushed quartz and optically matched mineral oil as proxies for sand and water allow the degree of saturation to be computed at pore-scale (0.7 mm resolution) enabling detailed investigations of the wave runup driven infiltration into a beach in a wave flume for a range of slopes and flow boundary conditions. The evolution of the wetting front resulting from wave runup on an initially unsaturated beach is described in detail, including the formation of an infiltration wedge in the subsurface of the swash zone and the wave-driven rise in fluid elevation inside the beach. The elevation of the runup for each event is found to be related closely to the saturation of the beach face, reaching an equilibrium state once the subsurface in the swash zone reaches capacity. The back wall boundary condition in the flume has a significant role in how subsurface flows increase saturation within the beach, especially with boundary head elevations greater than the initial phreatic surface. The results of these novel experimental observations are used to develop dimensionless relationships between the surface wave runup and the subsurface saturation rates. To improve monitoring and interpretation of future coastal groundwater studies, three distinct cross-shore regimes are defined for assessing change in subsurface fluid elevation in the beach.</p>","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JC021293","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143530518","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":"Intense Frazil Ice Production Promotes High Algal Biomass in Newly-Formed Sea Ice","authors":"Masato Ito,&nbsp;Keigo D. Takahashi,&nbsp;Ryosuke Makabe,&nbsp;Daisuke Hirano,&nbsp;Kay I. Ohshima,&nbsp;Takeshi Tamura,&nbsp;Shigeru Aoki","doi":"10.1029/2024JC021689","DOIUrl":"https://doi.org/10.1029/2024JC021689","url":null,"abstract":"<p>The coastal polynya formed off Cape Darnley, in the Southern Ocean, is a favorable site for a secondary phytoplankton bloom in the late summer and autumn. In late February of 2018, we conducted in-situ observations onboard an icebreaker and measured surface water chlorophyll <i>a</i> concentrations reaching 5.5 μg/L. Concurrently, in turbulent conditions associated with wind speeds exceeding 20 m/s, ocher-colored newly-formed sea ice, in the form of grease and pancake ice, spread across the polynya. Chlorophyll <i>a</i> concentrations measured in the grease and pancake ice were 47 times (260.0 μg/L) and 11 times (61.8 μg/L) higher than in the surrounding seawater, respectively. The corresponding sea ice algal concentration was sufficiently high to discolor the ice. Moreover, water temperatures were at or below the freezing point at depths shallower than 30 m, suggesting that suspended frazil ice came into contact with phytoplankton, which were particularly abundant in the water column during the bloom, and scavenged them. The diatom <i>Fragilariopsis curta</i> represented more than 83% of both total diatom cell abundance and biovolume in sea ice. Combining known algal growth rates with our results of chlorophyll <i>a</i> concentration in newly-formed ice, most of the ice algae originated from phytoplankton incorporated and accumulated by frazil ice. The considerable algal concentrations measured in new ice suggest that this accumulation process could contribute to the algal standing stock in Antarctic sea ice. The abundant bloom-forming phytoplankton incorporated into sea ice suggests that they could be a seed population for subsequent ice-algal or ice-edge bloom formation.</p>","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JC021689","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143527692","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":"Driving Factors of Dimethylated Sulfur Compounds in the Pearl River Estuary and Its Adjacent Coastal Waters: The Nonnegligible Role of Synechococcus","authors":"Xu-xu Gao,&nbsp;Jun-feng Chen,&nbsp;Xing Zhai,&nbsp;Qian Liu,&nbsp;Lian-bao Zhang,&nbsp;Yu-bin Hu,&nbsp;Ming-hao Zhu,&nbsp;Ye-ping Liu,&nbsp;Xiao-bo Zhao,&nbsp;Xue-ming Zhu,&nbsp;Gui-peng Yang,&nbsp;Ji-Hua Liu","doi":"10.1029/2024JC021764","DOIUrl":"https://doi.org/10.1029/2024JC021764","url":null,"abstract":"<p>Estuaries serve significant roles in the global dimethylated sulfur compounds (DSCs) cycle, however, the driving factors and biological contribution still need to be elucidated. A field investigation was conducted alongside diluted water in the Pearl River Estuary (PRE) and its adjacent coastal waters to explore the factors controlling the spatial variabilities of dimethylsulfide (DMS) and dimethylsulfoniopropionate (DMSP), as well as the role of phytoplankton in DSCs emissions in estuaries. Higher values of DSCs were observed in the freshwater-seawater mixing areas. Furthermore, the influx of the Pearl River diluted water (PRDW) caused a shift in higher DMSP and DMS values from nearshore to offshore. Dimethylated sulfur compounds did not show clear correlations with Chl-<i>a</i>, while a positive relationship existed between DSCs and certain eukaryotic phytoplankton species, such as dinoflagellates. Additionally, this study emphasized the crucial role of prokaryotic phytoplankton, mainly <i>Synechococcus</i>, in DSCs production. The abundance of <i>Synechococcus</i> exhibited significant positive correlations with DMS and DMSP, compared with eukaryotic phytoplankton. These results indicated that <i>Synechococcus</i> may be an essential biological factor driving DSCs production in estuaries. Overall, this study provides new insights to clarify the nonnegligible role of <i>Synechococcus</i> in the biogenic sulfur cycle, in which its contribution must be explored in greater detail in future studies.</p>","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143521955","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":"Influence of Melt Ponds and Floe Size on Apparent Optical Properties of Sea Ice: An Idealized Modelling Investigation","authors":"H. Zhang,&nbsp;M. Yu,&nbsp;P. Lu,&nbsp;M. Leppäranta,&nbsp;B. Cheng,&nbsp;J. Zhou,&nbsp;Q. Wang,&nbsp;X. Li,&nbsp;Z. Li","doi":"10.1029/2024JC021434","DOIUrl":"https://doi.org/10.1029/2024JC021434","url":null,"abstract":"<p>Melt ponds are usually modeled for light transfer as horizontally infinite water layers on level ice, and the albedo of floe is determined by a linear combination (LC) of melt pond and bare ice albedos weighted by their areal coverages. However, this method does not reflect the actual conditions because ice floes have a limited size. In the present study, an idealized two-dimensional Monte Carlo (MC) model was employed to investigate the influence of melt ponds and floe size on the apparent optical properties (AOPs) of summer sea ice. The results showed that the albedo and vertical light transmittance of large floes mainly depend on the melt pond fraction and ice thickness, which is consistent to previous results. However, also the floe size plays an important role in the AOPs of small floes. Two parameters were proposed to present the accuracy of the LC method for small floes with lower sea ice concentration: the ratios of sea ice albedo and transmittance determined by the LC (<i>α</i>_line, <i>T</i>_line) to the values in the MC model (<i>α</i>, <i>T</i>), <i>K</i>_α = <i>α</i>_line/<i>α</i>, and <i>K</i>_T = <i>T</i>_line/<i>T</i>, respectively. Due to the lateral transmittance, <i>K</i>_α, <i>K</i>_T ≥ 1 and asymptotically approach 1 with floe size increasing to infinity. To reduce the biases in albedo and transmittance due to floe size, new parameterization formulas were provided for <i>K</i>_α and <i>K</i>_T with the distance into the marginal ice zone and in different melting stages. The results have potential to be implemented into future sea ice models to correct the AOPs of small sea ice floes obtained via the LC method.</p>","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143521991","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":"Impacts of Coastal Nutrient Increases on the Marine Ecosystem in the East China Sea During 1982–2012: A Coupled Hydrodynamic-Ecological Modeling Study","authors":"Zhen Fang,&nbsp;Tian Feng,&nbsp;Yanjiahui Meng,&nbsp;Shuyu Zhao,&nbsp;Gang Yang,&nbsp;Yumiao Wang,&nbsp;Lihua Wang,&nbsp;Shuyao Shao,&nbsp;Weiwei Sun","doi":"10.1029/2024JC021553","DOIUrl":"https://doi.org/10.1029/2024JC021553","url":null,"abstract":"<p>In the past decades (1982–2012), the rapid increase in nitrogen and phosphorus inputs has led to a two-fold increase in nitrogen and phosphorus concentrations in the East China Sea. To investigate how the increasing nutrients in the East China Sea have been affecting the marine environment and growth of plankton, this paper establishes a modeling framework using the coupled ocean hydrodynamics-ecological model. Observational sea surface temperature, salinity, nutrients, and chlorophyll-a are compared with the predictions to validate the model performance. The study reveals that the concentrations of dissolved inorganic nitrogen (DIN) and phosphate (PO₄³⁻-P) are highest at the Yangtze River Estuary, slightly lower in the Zhejiang-Fujian nearshore, and much lower in the open sea, exhibiting significant seasonal variations closely related to the biomass of plankton. Over the past decades, DIN and PO₄³⁻-P concentrations at sea surface have increased by 294% and 253%, respectively, in the Yangtze River Estuary, and by over 291% and 76% in the Zhejiang-Fujian nearshore, both of which are characterized by high nitrogen-phosphorus ratios. As a result, the biomass of plankton at sea surface has increased by 26% averaged over the two regions. Sensitivity experiments indicate that the biomass enhancement in the Yangtze River Estuary is primarily attributed to the increase in phosphorus, whereas that over the Zhejiang-Fujian nearshore is explained by the combined effects of both nitrogen and phosphorus increases. This study contributes to the development of ecological conservation strategies for rivers and coastal seawaters in China in the future.</p>","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143497072","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}