Deep-Sea Research Part I-Oceanographic Research Papers最新文献

{"title":"Semidiurnal internal tides southeast of Miyakojima observed by the PIES array","authors":"Mingxuan Lu ,&nbsp;Zhao-Jun Liu ,&nbsp;Min Wang ,&nbsp;Xiao-Hua Zhu ,&nbsp;Chuanzheng Zhang ,&nbsp;Hua Zheng ,&nbsp;Ze-Nan Zhu ,&nbsp;Qun Ma","doi":"10.1016/j.dsr.2026.104649","DOIUrl":"10.1016/j.dsr.2026.104649","url":null,"abstract":"<div><div>The Ryukyu Island chain is one of the major generation regions for internal tides in the western North Pacific, notably generating strong semidiurnal internal tides. However, due to limited in situ observational data, the characteristics of internal tides east of Ryukyu Island chain remain unclear. In this study, we used pressure-sensor-equipped inverted echo sounders (PIES) deployed southeast of Miyakojima to assess the spatial structure and temporal variability of the internal tides from June 2015 to June 2017. Observations indicated stronger semidiurnal internal tides with larger fluctuations onshore than offshore. Both PIES observations and the satellite-derived product indicated that the M₂ internal tides propagated from the onshore to the offshore side; however, the amplitudes were substantially underestimated in the satellite product. The first mode of the Complex Empirical Orthogonal Function analysis revealed that the temporal amplitude exhibited clear seasonal variability, with larger amplitudes in spring (mean, 26.4 m) and autumn (mean, 22.2 m), and smaller amplitudes in summer (mean, 18.3 m) and winter (mean, 21.3 m). The pycnocline depth derived from the PIES observations also exhibited distinct seasonal variability, showing a strong correlation with sea level anomaly. These findings demonstrate that the temporal variability of the semidiurnal internal tides is likely attributable to mesoscale eddies, which modulate the pycnocline depth. Anticyclonic eddies deepen the pycnocline and suppress the amplitude of the semidiurnal internal tides. In nearly 70 % of the cases affected by mesoscale eddies during the observation period, decreased (increased) semidiurnal internal tide amplitudes occurred concurrently with a deepened (shoaled) pycnocline.</div></div>","PeriodicalId":51009,"journal":{"name":"Deep-Sea Research Part I-Oceanographic Research Papers","volume":"227 ","pages":"Article 104649"},"PeriodicalIF":2.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145924955","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":"Dissolved iron concentrations in the upper 500 m waters of the eastern Indian ocean","authors":"Han Su ,&nbsp;Jie Jin ,&nbsp;Shuo Jiang ,&nbsp;Wei Zheng ,&nbsp;Zheng Bo Liu ,&nbsp;Yan Chang ,&nbsp;Xunchi Zhu ,&nbsp;Jing Zhang","doi":"10.1016/j.dsr.2025.104629","DOIUrl":"10.1016/j.dsr.2025.104629","url":null,"abstract":"<div><div>Dissolved iron (DFe) in ocean waters often limit phytoplankton growth because of its low bioavailability. In this study, we examined data on the surface and sectional distribution of DFe in the eastern Indian Ocean (EIO) to understand its influence on the surface and upper waters. Our sampling covered the upper 500 m of the EIO between 10°S and 10°N and 78°E−100°E, encompassing the Bay of Bengal (BoB) and the equatorial EIO during the 2017 (March–April) and 2018 (March–May) cruises. In surface waters, DFe concentrations in the Bay of Bengal (0.35 ± 0.06 nmol/kg, n = 20) and at station I507 (the extension of the Indonesian Throughflow, ITF, 0.36 nmol/kg) were higher than those in the equatorial EIO (0.27 ± 0.04 nmol/kg, n = 76). The vertical distribution of DFe exhibited significant spatial differences, with higher concentrations in the BoB than in the equatorial EIO, recorded at 0.79 ± 0.25 nmol/kg and 0.64 ± 0.26 nmol/kg, respectively. The distribution of DFe in the EIO was influenced by three types of water masses and hydrographic features, including the extension of ITF. The relative contributions of different DFe sources, such as river input, dust deposition, and other external sources, varied between the equatorial EIO and BoB as well as between the Indo-Pacific and western Pacific Oceans. Furthermore, the external Fe (Fe∗) and the molar ratios of macronutrients suggest that nitrogen is a more significant limiting factor than Fe in both the BoB and equatorial EIO surface waters. Therefore, our findings contribute to understanding of the distribution patterns and influencing factors of the BoB and the equatorial EIO.</div></div>","PeriodicalId":51009,"journal":{"name":"Deep-Sea Research Part I-Oceanographic Research Papers","volume":"227 ","pages":"Article 104629"},"PeriodicalIF":2.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145684998","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":"Antarctic Bottom Water contraction drives abyssal ocean warming along SAMBA-West line (34.5°S) in the Argentine basin","authors":"Daniel M.C. Santos ,&nbsp;Tiago C. Biló ,&nbsp;Dante C. Napolitano ,&nbsp;Renellys C. Perez ,&nbsp;Paulo S. Polito ,&nbsp;Jonathan Gula ,&nbsp;Shenfu Dong ,&nbsp;Edmo J.D. Campos ,&nbsp;Olga T. Sato","doi":"10.1016/j.dsr.2025.104627","DOIUrl":"10.1016/j.dsr.2025.104627","url":null,"abstract":"<div><div>We present an updated assessment of abyssal temperature trends in the Argentine Basin using expanded hydrographic and moored observations from the SAMBA-West line. The study addresses two main questions: (1) What is the spatial distribution of the abyssal warming along the SAMBA-West line? (2) What mechanisms drive the observed changes? Using output from a high-resolution numerical simulation, we first characterize how the abyssal flow near 34.5°S relates to the broader basin-scale circulation, providing context for interpreting the observations. Within this framework, we find that SAMBA-West is situated within a dynamically complex junction of deep boundary currents and recirculation pathways in the northwestern portion of the Argentine Basin. A coherent, statistically significant warming trend is found across most of the array and vertically throughout the AABW layer, primarily due to its vertical contraction, likely reflecting reduced formation or export of the AABW.</div></div>","PeriodicalId":51009,"journal":{"name":"Deep-Sea Research Part I-Oceanographic Research Papers","volume":"227 ","pages":"Article 104627"},"PeriodicalIF":2.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145684991","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":"Global distribution of suitable habitats for deep-sea sponges based on machine learning","authors":"Jichao Yang ,&nbsp;Tongbo Xu ,&nbsp;Xuelei Zhang ,&nbsp;QinZeng Xu ,&nbsp;Guoyu Xu ,&nbsp;Guanhong Zhai ,&nbsp;Minxing Dong","doi":"10.1016/j.dsr.2025.104642","DOIUrl":"10.1016/j.dsr.2025.104642","url":null,"abstract":"<div><div>As terrestrial resources become increasingly scarce, the importance of developing deep-sea mineral resources has grown significantly. However, the harsh deep-sea environment and limited availability of species distribution data pose major challenges to the protection and management of deep-sea ecosystems. This study combined global marine environment data and limited deep-sea sponge distribution records to construct a high-resolution habitat suitability prediction model based on machine learning technology. By selecting six key environmental variables such as water depth, seawater nutrients, chemical composition, and seafloor topography, Random Forest, XGBoost, and the integrated learning algorithm Ensemble Median were used to predict the global potential distribution of deep-sea sponges. Model evaluation shows that the integrated model is significantly better than the single model in terms of prediction accuracy, AUC value, TSS value and Kappa coefficient, and has good robustness and reliability. The research results provide a scientific basis for the protection of deep-sea sponges, and provide an important reference for the rational development of deep-sea resources and maintenance of marine ecological balance, laying a theoretical foundation for the planning and policy formulation of deep-sea protected areas.</div></div>","PeriodicalId":51009,"journal":{"name":"Deep-Sea Research Part I-Oceanographic Research Papers","volume":"227 ","pages":"Article 104642"},"PeriodicalIF":2.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145976688","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":"Petrogenesis of lavas from the southern Kyushu-Palau Ridge, Philippine Sea Plate: Implications for the arc rifting of the proto-Izu-Bonin-Mariana Arc","authors":"Zhenxuan Liu ,&nbsp;Quanshu Yan ,&nbsp;Xuefa Shi ,&nbsp;Gang Yang ,&nbsp;Yanguang Liu","doi":"10.1016/j.dsr.2025.104646","DOIUrl":"10.1016/j.dsr.2025.104646","url":null,"abstract":"<div><div>The Kyushu-Palau Ridge (KPR), a remnant arc that split from the proto-Izu-Bonin-Mariana (IBM) arc, plays a significant role in understanding the intra-oceanic arc rifting and the geological evolution of the Philippine Sea Plate (PSP). There is still a paucity of data on the volcanism of the southern KPR, particularly, the influence of arc rifting on magma composition and arc evolution remains to be elucidated. This study presents new major and trace element geochemical compositions as well as K-Ar age of the basaltic lavas from the southern KPR (south of 22° N). Major and trace elements suggest that southern KPR lavas exhibit a strong tholeiitic affinity and limited contribution from subduction components (i.e., hydrous melts and aqueous fluids). Geochemically, the southern KPR shows similarities to the infant IBM arc and differs from the northern KPR as well as the more evolved mature island arc. The wide ranges in Nb/Yb (0.14–3.68) and Zr/Nb (6.43–115.44) ratios as well as the model calculations of samples demonstrate that the lavas were formed through low-degree (&lt;15 %) partial melting of heterogeneous sub-arc mantle source in the spinel lherzolite facies. This study advances a conceptual model elucidating KPR evolution, proposing that the PSP kinematics with the variable arc rifting conditions of the proto-IBM arc led to the separation of the KPR. The arc rifting-spreading event prevented it from evolving into a mature arc.</div></div>","PeriodicalId":51009,"journal":{"name":"Deep-Sea Research Part I-Oceanographic Research Papers","volume":"227 ","pages":"Article 104646"},"PeriodicalIF":2.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145884365","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":"Phosphorus species in surface sediments of the Kermadec Trench: Distribution and controlling factors","authors":"Zhihao Xiong ,&nbsp;Yuanqing Chen ,&nbsp;Hengchao Xu ,&nbsp;Liang Dong ,&nbsp;Zijun Wu","doi":"10.1016/j.dsr.2025.104639","DOIUrl":"10.1016/j.dsr.2025.104639","url":null,"abstract":"<div><div>Hadal trenches, as key deep-sea environments for organic matter burial and microbial respiration, are therefore recognized hotspots for early diagenesis. Although phosphorus (P) cycling has been extensively studied in marginal sea sediments, its behavior in hadal trench sediments remains poorly understood. This study examines sedimentary P partitioning in the Kermadec Trench to identify the dominant controls on P speciation. Geochemical data reveal that P distribution is collectively influenced by redox conditions, organic matter content, and volcanic inputs. In the southern part of the trench, higher sedimentary TOC content directly enhances the preservation of iron-bound P (P_Fe, 21 % of total P) and organic P (P_org, 10 %). In contrast, northern sites, which are enriched in volcanic material (Fe_TOT up to 63.2 mg g⁻¹), exhibit lower retention of reactive P (P_rea, 40–45 %), likely due to Fe(III)-mediated dissimilatory iron reduction, along with higher volcanic silicate iron. This spatial heterogeneity exhibits variation influenced by hydrodynamic processes: deep western boundary currents carry terrigenous sediments northward, whereas surface currents distribute volcanic ash southward. Relative to continental shelves, hadal trenches display a greater predominance of detrital P burial (P_detrital, 53 % of total P), as well as elevated proportions of iron-bound P (P_Fe,16 %) and authigenic apatite (P_authi, 20 %). Our findings reveal volcanic activity as a critical control on phosphorus cycling in hadal systems, indicating that these environments are governed by a distinct set of biogeochemical processes.</div></div>","PeriodicalId":51009,"journal":{"name":"Deep-Sea Research Part I-Oceanographic Research Papers","volume":"227 ","pages":"Article 104639"},"PeriodicalIF":2.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145736980","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 sea surface temperature variability in the northwestern Indian ocean","authors":"Hongxuan Pan ,&nbsp;Hongwei Liu ,&nbsp;Yongliang Duan ,&nbsp;Chongguang Pang","doi":"10.1016/j.dsr.2025.104641","DOIUrl":"10.1016/j.dsr.2025.104641","url":null,"abstract":"<div><div>This study investigates the seasonal variability and underlying mechanisms of sea surface temperature (SST) in the Somali upwelling region of the northwestern tropical Indian Ocean (TIO), based on high-resolution ocean reanalysis and observational datasets. Motivated by the distinct bimodal SST cycle in this region — featuring two warming (spring and autumn) and two cooling (summer and winter) periods — we conduct a detailed mixed-layer heat budget analysis to quantify the relative contributions of atmospheric forcing and oceanic processes. While net surface heat flux (NSHF) dominates both warming phases, the underlying mechanisms differ significantly. For spring warming, it is primarily driven by increased shortwave radiation and weakened winds. In contrast, autumn warming — despite stronger NSHF — is partially offset by vertical entrainment and horizontal advection. For the cooling phases, summer SST decline is driven by dynamic oceanic processes such as vertical entrainment and horizontal advection under the southwest monsoon, while winter cooling is controlled mainly by enhanced latent heat loss. Compared to the Java upwelling region, which displays a weaker unimodal SST pattern, the Somali system exhibits more complex monsoon–ocean interactions. While earlier basin-scale modeling studies have identified general seasonal controls in the northern Indian Ocean, our region-specific, observation-constrained analysis uncovers pronounced asymmetries between distinct warming and cooling phases. These findings emphasize the critical role of monsoon-driven, phase-dependent air–sea interactions in shaping the seasonal SST variability in the northwestern TIO.</div></div>","PeriodicalId":51009,"journal":{"name":"Deep-Sea Research Part I-Oceanographic Research Papers","volume":"227 ","pages":"Article 104641"},"PeriodicalIF":2.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145736981","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":"Machine learning reconstruction of multiyear missing nutrient data along the 137°E section, northwestern Pacific","authors":"Xinling Song ,&nbsp;Zhenyan Wang ,&nbsp;Yijia Jia ,&nbsp;Meihan Zhao ,&nbsp;Yujie Fu","doi":"10.1016/j.dsr.2025.104638","DOIUrl":"10.1016/j.dsr.2025.104638","url":null,"abstract":"<div><div>Nutrients are fundamental to marine primary production and serve as key tracers of deep-sea circulation. However, continuous in-situ nutrient observations in the open ocean remain challenging. Despite over fifty years of surveys by the Japan Meteorological Agency along the 137°E section in the northwestern Pacific, substantial missing data persist, requiring reconstruction to support future studies on deep nutrient transport in carbon cycling. This study applies three machine learning (ML) methods—Support Vector Regression (SVR), Random Forest (RF), and Extreme Gradient Boosting (XGBoost)—to develop an ML framework for reconstructing summer nutrient data (1997–2022) along this section. The results demonstrate that, compared to baseline models (multiple linear regression, Artificial Neural Networks and Deep Neural Networks), these ML methods achieved a favorable balance between accuracy and stability in predicting nutrients, with RF consistently performing best. Shapley values reveal that RF effectively captures key features like temperature and depth, relies less on weak predictors, and models nonlinear interactions more robustly, which explains its advantage over SVR and XGBoost. RF, selected as the optimal model, was used to reconstruct the three nutrients, capturing characteristic zonal and vertical patterns. Furthermore, compared to the Global Ocean Biogeochemistry Hindcast product, RF achieved a 74–79 % reduction in RMSEs across the three nutrients. This study demonstrates that ML methods (particularly RF) achieve superior accuracy for nutrient reconstruction within the analyzed spatiotemporal scope and may provide a practical framework for nutrient reconstruction in other high-missing-rate marine regions, supporting biogeochemical and deep-sea process studies.</div></div>","PeriodicalId":51009,"journal":{"name":"Deep-Sea Research Part I-Oceanographic Research Papers","volume":"227 ","pages":"Article 104638"},"PeriodicalIF":2.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145684996","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":"Export production in the upper ocean using f-ratios in the Bay of Bengal using a remote sensing approach","authors":"V.V.S.S. Sarma ,&nbsp;B. Sridevi","doi":"10.1016/j.dsr.2025.104647","DOIUrl":"10.1016/j.dsr.2025.104647","url":null,"abstract":"<div><div>The fraction of the primary production leaving the photic zone is important to understand the strength of the biological pump and carbon sequestration. This fraction intensifies the oxygen minimum zone by supporting life in the deeper ocean. The <em>f</em>-ratio, the new-to-total production ratio, represents the exportable production below the euphotic zone under specific conditions. Based on the measured <em>f</em>-ratios by ¹⁵N tracer and δ¹⁵N of suspended matter and their relation with sea surface temperature, salinity and chlorophyll-a (Chl-a), spatial and temporal variations in <em>f</em>-ratios were derived in the Bay of Bengal using remote sensing data. The ¹⁵N tracer and δ¹⁵N suspended matter methods give photic zone and mixed layer mean <em>f</em>-ratios, respectively. The basin-mean photic zone <em>f</em>-ratios were higher during winter, followed by summer and fall monsoon, with higher <em>f</em>-ratios along the coastal Bay of Bengal associated with the spread of riverine nutrients during fall and summer. The higher <em>f</em>-ratios in the northern Bay of Bengal during winter and spring were associated with atmospheric deposition of nutrients. The mixed layer and photic zone mean <em>f</em>-ratios in the Bay of Bengal were 0.37 ± 0.06, and 0.57 ± 0.10, respectively, suggesting that half of the primary production in the photic zone is exported to the aphotic zone. The estimated new production using external sources of nitrogen supported ∼59 ± 16 TgC annually. Based on total production from the Vertically Generalized Primary Production Model (VGPM), the <em>f</em>-ratio was estimated as 0.33 ± 0.05 using external sources, and it is consistent with the mixed layer mean <em>f</em>-ratio derived from δ¹⁵N of suspended matter (0.37 ± 0.06). Based on the mean <em>f</em>-ratio in the photic zone from external sources and VGPM production, about 60 ± 20 TgC y⁻¹ of primary production sinks to the depth below the photic zone. The export production at the 100 m depth was measured to be ∼10 ± 5 TgC y⁻¹ using thorium isotopes, suggesting that ∼50 ± 15 TgC y⁻¹ of the primary produced organic matter may be utilized either through heterotrophic activity in a depth range between 60 and 100 m or transported horizontally. This estimate is consistent with the dark respiration rates in this depth zone and also the apparent oxygen utilization. The seasonal and spatial variations in <em>f</em>-ratios derived in this work may be used in the numerical model to improve the simulation and prediction of the carbon cycle in the Indian Ocean.</div></div>","PeriodicalId":51009,"journal":{"name":"Deep-Sea Research Part I-Oceanographic Research Papers","volume":"227 ","pages":"Article 104647"},"PeriodicalIF":2.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145924956","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":"Quantifying the deep-sea cold seep gas flux using multibeam water column data: A case study in the Shenhu area of the South China sea","authors":"Feng Wang ,&nbsp;Sai Mei ,&nbsp;Xianhai Bu ,&nbsp;Fanlin Yang ,&nbsp;Jianbing Chen ,&nbsp;Zhao Zhao","doi":"10.1016/j.dsr.2025.104644","DOIUrl":"10.1016/j.dsr.2025.104644","url":null,"abstract":"<div><div>Accurately quantifying the gas flux released by cold seeps into the water is significant for exploring gas hydrates and understanding the marine carbon cycle. While multibeam water column data (WCD) commonly used to detect gas plumes, its quantitative application may be limited by single frequency mode and inaccurately calibrated backscatter intensity. This study develops a novel WCD-based gas flux quantification method. First, a parallel genetic algorithm optimizes bubble size distribution (BSD) parameters by minimizing residuals between measured and theoretical backscatter intensities. Subsequently, kernel density estimation derives robust bubble volume from optimized BSD parameters. Finally, gas flux is calculated by combining bubble volume and bubble rising speed. Simulation experiments validate the robustness of the proposed method, with field application in the Shenhu area of the South China Sea yielding two key results: observed gas plumes exhibit maximum ascent heights of ∼820 m with the total gas flux reaching (6 ± 1) × 10⁴ L/min, and statistically significant correlations between backscatter intensity and gas flux confirm methodological validity. The developed model establishes an efficient approach for WCD-based gas flux quantification, providing valuable insights for deep-sea emissions quantification and marine biogeochemical cycle modeling.</div></div>","PeriodicalId":51009,"journal":{"name":"Deep-Sea Research Part I-Oceanographic Research Papers","volume":"227 ","pages":"Article 104644"},"PeriodicalIF":2.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145840389","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}