Journal of Geophysical Research-Oceans最新文献_第4页

Impacts of the Po River on Adriatic Sea Hydrodynamics and Interbasin Exchanges 波河对亚得里亚海水动力和流域间交换的影响

IF 3.3 2区地球科学

Journal of Geophysical Research-Oceans Pub Date : 2025-06-29 DOI: 10.1029/2024JC022196

Javad Babagolimatikolaei, David M. Schultz, Samuel Draycott, Ben Parkes

{"title":"Impacts of the Po River on Adriatic Sea Hydrodynamics and Interbasin Exchanges","authors":"Javad Babagolimatikolaei, David M. Schultz, Samuel Draycott, Ben Parkes","doi":"10.1029/2024JC022196","DOIUrl":"https://doi.org/10.1029/2024JC022196","url":null,"abstract":"One-third of the fresh water in the Adriatic Sea originates from the Po River, influencing the heat, salt budget, and circulation (or hydrodynamics) of the Adriatic. Although many studies highlight the Po River's impact on the Adriatic, uncertainty remains in understanding the potential consequences if the Po River were to dry up due to climate change. Here, we show the dependence of the heat and salt budgets, as well as the hydrodynamics of the Adriatic, on the discharge of the Po River. We use an ocean model of the Adriatic Sea under two scenarios: The control simulation WITHPO reflecting natural conditions during 2018 and incorporating the Po River's freshwater input and an experimental simulation NOPO with the freshwater input turned off. WITHPO generally results in the surface waters in the northern basin being as much as 1.5°C warmer throughout the year, but colder in the spring by 2°C. WITHPO shows a salinity decrease ranging from 0.35 to 1 PSU at the surface. The sea surface height is 5 cm higher in the WITHPO, with the greatest effects observed along the western coast of the Adriatic Sea. The Po River's inflow increases surface outflow and inflow near the seabed between the Adriatic and Ionian Seas. Our results underscore the Adriatic Sea's dependency on Po River discharge and highlight the potential consequences of climate change producing reduced or zero discharge.","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 7","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JC022196","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144514677","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}

引用次数: 0

Particle Export Fluxes in the Southern Ocean: Importance of Nonheterotrophic Processes in POC Flux Attenuation 南大洋颗粒输出通量：非异养过程在POC通量衰减中的重要性

IF 3.3 2区地球科学

Journal of Geophysical Research-Oceans Pub Date : 2025-06-29 DOI: 10.1029/2024JC021607

Frédéric A. C. Le Moigne, Katsiaryna Pabortsava, María Villa-Alfageme, Nathan Briggs, Chelsey A. Baker, Heather A. Bouman, Chance J. English, Sabena Blackbird, Stephanie A. Henson, Hugh Venables, Craig A. Carlson, C. Mark Moore, Jack Williams, Adrian P. Martin

{"title":"Particle Export Fluxes in the Southern Ocean: Importance of Nonheterotrophic Processes in POC Flux Attenuation","authors":"Frédéric A. C. Le Moigne, Katsiaryna Pabortsava, María Villa-Alfageme, Nathan Briggs, Chelsey A. Baker, Heather A. Bouman, Chance J. English, Sabena Blackbird, Stephanie A. Henson, Hugh Venables, Craig A. Carlson, C. Mark Moore, Jack Williams, Adrian P. Martin","doi":"10.1029/2024JC021607","DOIUrl":"https://doi.org/10.1029/2024JC021607","url":null,"abstract":"The ocean contributes to regulating atmospheric CO2 levels via the biological carbon pump (BCP). One critical aspect of the BCP is the depth at which sinking particulate organic carbon (POC) remineralizes in the mesopelagic zone (200–1,000 m). In the Southern Ocean, the circulation is such that the products generated from POC remineralization may have drastically different fates depending on (a) the latitude at which sinking particulate material is produced and (b) the depth at which its remineralization occurs. Here, we assess latitudinal and depth variations of POC export marine aggregate abundance and composition in the Southeast Pacific sector of the Southern Ocean. We show changes in flux attenuation depth horizons in the upper mesopelagic in the subantarctic zone. These correspond to rapid particle accumulation below the depth of the euphotic zone followed by abrupt export. We believe that such rapid changes may be linked to diatom life cycles, including resting cell and spore formation and resulting changes in particle sinking velocities rather than attenuation due to heterotrophic degradation or solubilization in the upper mesopelagic zone. We further discuss the occurrence of such features in the Southern Ocean and at the global scale. Our results highlight the importance of alternative flux attenuation processes, such as sudden changes in particles sinking velocities, in explaining variability in organic carbon sequestration by the ocean's BCP.","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 7","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JC021607","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144514847","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}

引用次数: 0

Investigating Hurricane-Induced Salt Variation Across the Land-Estuary-Ocean Continuum Using a Dynamically Coupled Hydrological-Ocean Model 利用动态耦合水文-海洋模型研究陆地-河口-海洋连续体中飓风引起的盐变化

IF 3.3 2区地球科学

Journal of Geophysical Research-Oceans Pub Date : 2025-06-28 DOI: 10.1029/2024JC022011

Xiaochen Zhao, Z. George Xue, Daoyang Bao, John Warner, Yanda Ou

{"title":"Investigating Hurricane-Induced Salt Variation Across the Land-Estuary-Ocean Continuum Using a Dynamically Coupled Hydrological-Ocean Model","authors":"Xiaochen Zhao, Z. George Xue, Daoyang Bao, John Warner, Yanda Ou","doi":"10.1029/2024JC022011","DOIUrl":"https://doi.org/10.1029/2024JC022011","url":null,"abstract":"Salinity variations across the Land-Estuary-Ocean (LEO) continuum are critical for coastal ecosystems and impact the socioeconomic benefits to local communities. However, evaluating these variations is challenging due to the complex interactions of terrestrial and oceanic processes, including river discharge, winds, tides, sea level rise, and storms. This study incorporates a salinity module into a newly developed dynamically coupled hydrological-ocean model on the COAWST platform, which is, to the best of our knowledge, the first process-based modeling that achieves seamless two-way land-ocean water and salt exchanges across the LEO continuum, facilitating simulations of landward salt input and transport. Using Hurricane Florence (2018) as a case study, we examined how various physical processes influence salinity dynamics and freshwater plume development in the Cape Fear River Estuary, North Carolina. The model simulated saltwater intrusion into freshwater wetlands upstream of the estuary and demonstrated that salinity in the estuary was initially regulated by wind-driven water level gradients, followed by a dominant influence from significant river runoff. In the coastal ocean, runoff created a large freshwater plume that moved westward, driven by the interplay between runoff, winds, and the estuary's geomorphology. The excellent performance of the coupling approach for salinity simulation underscores the importance of the seamless transport of water and salt at the land-ocean interface. This study demonstrates that the coupled model is a valuable tool for representing saltwater intrusion, tracking coastal pollutants, and understanding water and material exchange across the LEO continuum.","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 7","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JC022011","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144503175","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}

引用次数: 0

Drivers of Water Mass Volume Changes in the Nordic Seas (2005–2020) 北欧海水质量体积变化的驱动因素（2005-2020）

IF 3.3 2区地球科学

Journal of Geophysical Research-Oceans Pub Date : 2025-06-27 DOI: 10.1029/2024JC022209

Lucas Almeida, Camille Lique, Nicolas Kolodziejczyk, Damien Desbruyères

{"title":"Drivers of Water Mass Volume Changes in the Nordic Seas (2005–2020)","authors":"Lucas Almeida, Camille Lique, Nicolas Kolodziejczyk, Damien Desbruyères","doi":"10.1029/2024JC022209","DOIUrl":"https://doi.org/10.1029/2024JC022209","url":null,"abstract":"The Nordic Seas are integral parts of the Atlantic meridional overturning circulation and a key region for the global climate. In this study, we combine observational products, largely derived from the Argo array, to examine the changes affecting ocean conditions in the different regions of the Nordic Seas from 2005 to 2020. Significant warming and deepening of isopycnal surfaces have been found across all regions since 2013, resulting in a volume increase of the surface layer above the σ0 < 27.8 kg m−3 isopycnal. A volume budget over three isopycnal layers is built to disentangle the relative roles played by the atmospheric forcing that results in local water mass transformation and large-scale advection. In eastern basins, an increase in both the advection of Atlantic water and surface water mass transformation led to an expansion of the surface layer after 2012. In contrast, changes found in the Greenland Sea result primarily from a decrease in transport convergence and changes in the surface forcing that ventilates all layers of the region. Our analysis also highlights that an improved sampling of the region, including toward greater depths and on the East Greenland shelves, is required to reduce uncertainties in the water mass transformation budget of the Nordic Seas and to better understand the mechanisms at play.","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 7","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JC022209","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144493036","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}

引用次数: 0

Drivers and Variability of Intensified Subsurface Ocean Acidification Trends at Station ALOHA ALOHA站地表下海洋酸化趋势加剧的驱动因素和变率

IF 3.3 2区地球科学

Journal of Geophysical Research-Oceans Pub Date : 2025-06-27 DOI: 10.1029/2024JC022251

Lucie A. C. M. Knor, Christopher L. Sabine, John E. Dore, Angelicque E. White, James Potemra

{"title":"Drivers and Variability of Intensified Subsurface Ocean Acidification Trends at Station ALOHA","authors":"Lucie A. C. M. Knor, Christopher L. Sabine, John E. Dore, Angelicque E. White, James Potemra","doi":"10.1029/2024JC022251","DOIUrl":"https://doi.org/10.1029/2024JC022251","url":null,"abstract":"This study seeks to identify drivers of differences in ocean acidification (OA) rates throughout the upper ocean at Station ALOHA in the North Pacific Subtropical Gyre (NPSG). OA is intensified in the subsurface due to increases in natural and anthropogenic carbon pools, and their interactions. Enhanced subsurface trends are found for all OA indicators. This includes parameters that have previously been identified to exhibit nonlinear interactions between anthropogenic and natural carbon ([H+], pCO2, pH, Revelle Factor), as well as parameters that are not subject to this response (aragonite saturation state (ΩAr)). Different parameters have trend maxima in each of the water masses in the upper 500 m, driven by different mechanisms. Enhanced acidification is noted in the North Pacific Tropical Water (NPTW) from 2015 until 2020. This is due to the interplay of a circulation slowdown during a prolonged negative phase of the North Pacific Gyre Oscillation (NPGO) with other anomalous atmospheric forcing that altered source water chemistry, including large-scale freshening. Sustained increased acidification is also associated with freshening and cooling in the Subsurface Salinity Minimum (SSM) over the whole time-series, with considerable oxygen loss and nutrient increases. In the North Pacific Intermediate Water (NPIW), a well-documented circulation slowdown has led to enhanced CO2 ingrowth from remineralization, buffered by increasing carbonate dissolution. Local changes seem to play a smaller role. In the SSM and NPTW, enhanced acidification is associated with cooling and freshening, providing new insights on how OA can accelerate beyond the well-documented warming and souring of the ocean.","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 7","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JC022251","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144492888","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}

引用次数: 0

Impacts of Atmospheric Near-Surface Stability on the Arctic Summer Air-Sea Heat Budget Using Uncrewed Surface Vehicles 大气近地表稳定性对北极夏季海气热收支的影响

IF 3.3 2区地球科学

Journal of Geophysical Research-Oceans Pub Date : 2025-06-26 DOI: 10.1029/2024JC022313

Yanxu Chen, Lisan Yu, Chidong Zhang

{"title":"Impacts of Atmospheric Near-Surface Stability on the Arctic Summer Air-Sea Heat Budget Using Uncrewed Surface Vehicles","authors":"Yanxu Chen, Lisan Yu, Chidong Zhang","doi":"10.1029/2024JC022313","DOIUrl":"https://doi.org/10.1029/2024JC022313","url":null,"abstract":"The atmospheric marine boundary layer (AMBL) plays a crucial role in regulating air-sea interactions and influencing the climate system, particularly in the Arctic due to its high sensitivity to global warming. This study utilizes five years (2018–2022) of saildrone data from the Bering-Chukchi-Beaufort Seas to analyze atmospheric near-surface stability and air-sea turbulent heat fluxes during the Arctic summer. By applying Monin-Obukhov similarity theory, we investigate the temporal variability and mechanisms that influence AMBL stability. Our findings reveal two distinct regimes of stable and unstable conditions in two contrasting years of 2020 and 2022. In 2020, cold air advection driven by northerly winds consistently destabilizes the AMBL, leading to increased oceanic heat loss. In 2022, however, southerly winds and warm air advection stabilize the AMBL, suppressing air-sea heat exchanges. The temporal variation of turbulent heat fluxes is primarily driven by air-sea temperature differences, with the magnitude of wind speed and its temperature covariance serving as secondary factors. We also show the importance of skin temperature measurements from saildrones for improving estimates of turbulent heat fluxes. These insights enhance our understanding of Arctic air-sea interactions and inform climate models, underscoring the need for high-resolution observations in polar regions and the improvement of bulk flux parameterization for stable AMBL.","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 7","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144482355","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}

引用次数: 0

Anthropogenic Carbon Dynamics: Concentrations, Transports, and Trends in the Western North Atlantic Subtropical Gyre 人为碳动力学：北大西洋副热带环流的浓度、运输和趋势

IF 3.3 2区地球科学

Journal of Geophysical Research-Oceans Pub Date : 2025-06-26 DOI: 10.1029/2025JC022493

Daniel Santana-Toscano, Peter Brown, Alonso Hernández-Guerra

{"title":"Anthropogenic Carbon Dynamics: Concentrations, Transports, and Trends in the Western North Atlantic Subtropical Gyre","authors":"Daniel Santana-Toscano, Peter Brown, Alonso Hernández-Guerra","doi":"10.1029/2025JC022493","DOIUrl":"https://doi.org/10.1029/2025JC022493","url":null,"abstract":"The ocean acts as a major carbon sink, absorbing anthropogenic CO2 and mitigating climate change. The North Atlantic Ocean, particularly the western North Atlantic Subtropical Gyre (NASG), plays a crucial role in this process, yet the mechanisms governing the transport of anthropogenic carbon (Canth) remain incompletely understood. In this study, we quantify Canth transport across the western NASG using hydrographic observations from repeat meridional sections (A20 and A22) and an inverse box model approach. We show that Canth transport has increased over the past four decades, primarily in surface and intermediate layers, driven by rising atmospheric CO2 concentrations rather than significant changes in mass transport. The strongest Canth transport occurs in the Subtropical Underwater (STUW) and Subtropical Mode Water (STMW) layers, following the circulation patterns of the Gulf Stream (GS) and its recirculation. While deep and bottom layers, such as Labrador Sea Water, Iceland-Scotland Overflow Water, and Denmark Strait Overflow Water, exhibit weaker and more variable transport, the overall trend reflects increasing Canth sequestration across the region. Long-term atmospheric CO2 trends from four global monitoring stations are compared with Canth levels in the western NASG, showing that both have steadily increased since 1970. Slight variations in these trends imply that factors such as ocean circulation, temperature fluctuations, and water mass dynamics could affect the region's efficiency in CO2 uptake.","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 7","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025JC022493","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144482354","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}

引用次数: 0

Free Long Wave Generation: Breakpoint Forcing Versus Bound Wave Release 自由长波产生：断点强迫与束缚波释放

IF 3.3 2区地球科学

Journal of Geophysical Research-Oceans Pub Date : 2025-06-26 DOI: 10.1029/2025JC022377

Stephanie Contardo, Ryan J. Lowe, Francois Dufois, Jeff E. Hansen, Graham Symonds

{"title":"Free Long Wave Generation: Breakpoint Forcing Versus Bound Wave Release","authors":"Stephanie Contardo, Ryan J. Lowe, Francois Dufois, Jeff E. Hansen, Graham Symonds","doi":"10.1029/2025JC022377","DOIUrl":"https://doi.org/10.1029/2025JC022377","url":null,"abstract":"When wind waves break in the nearshore, free long (infragravity) waves are generated through two mechanisms: breakpoint forcing and bound wave release. Previous studies have highlighted that lower frequency groups breaking on steep slopes favor long wave generation by breakpoint forcing, whereas higher frequency groups breaking on mild slopes favor bound wave release. However, no study has established and demonstrated quantitative thresholds for when each mechanism will dominate. In this paper, we use a one-dimensional linear numerical model to quantify each mechanism and assess their relative dominance in free long wave generation, as a function of wave and bathymetry parameters. The results show that the individual contributions of breakpoint forcing and bound wave release do not add up linearly to the total long wave energy generated from both mechanisms due to the phase differences between free long waves generated from each mechanism. The combination of mechanisms always results in a net smaller long wave amplitude. The normalized bed slope parameter is shown to be effective in differentiating between the dominance of the breakpoint-forced and bound wave release mechanisms. The efficiency of breakpoint forcing is found to be independent of bed slope, wave group frequency and short-wave period. Therefore, the relative importance of each mechanism to long wave generation depends mainly on the efficiency of the bound wave release, which varies with these parameters. Overall, the bound wave release mechanism tends to dominate under most conditions, except for cases with low infragravity frequencies that occur on steep slopes (e.g., typical of reef environments).","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 7","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025JC022377","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144482356","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}

引用次数: 0

Hydraulic Control of Submarine Glacial Melt in Greenlandic Fjords 格陵兰峡湾海底冰川融化的水力控制

IF 3.3 2区地球科学

Journal of Geophysical Research-Oceans Pub Date : 2025-06-26 DOI: 10.1029/2024JC021257

Jonathan Wiskandt, Johan Nilsson, Inga Monika Koszalka

{"title":"Hydraulic Control of Submarine Glacial Melt in Greenlandic Fjords","authors":"Jonathan Wiskandt, Johan Nilsson, Inga Monika Koszalka","doi":"10.1029/2024JC021257","DOIUrl":"https://doi.org/10.1029/2024JC021257","url":null,"abstract":"Ocean-driven submarine basal melt of the Greenland Ice Sheet remains a major source of uncertainty in climate projections of future sea level rise based on ice sheet modeling. State-of-the-art parameterizations focus on the properties of the ocean water reaching the marine-terminating glaciers, processes at the ice-ocean interface and subglacial discharge to estimate submarine basal melt. This study uses 2-dimensional, nonrotating, high-resolution ocean simulations complemented by theory and observations to quantify two effects of fjord bathymetry (sills) on the thermal forcing with consequences for the basal melt. These effects are the recirculation (reflux) of glacially modified water due to hydraulic control at the sill (which we study in detail) and the cooling of the inflow due to the restriction of the deepest and warmest Atlantic water inflow. For a fixed sill depth, an increase in subglacial discharge can make the exchange flow hydraulically controlled. Our results suggest that basal melt parameterizations should account for fjord bathymetry, and outline a road map to guide future parameterization developments relevant to narrow fjords.","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 7","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JC021257","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144482358","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}

引用次数: 0

Biogeochemical Implication of Massive Episodic Flood Deposition: Model-Data Integration 大规模幕式洪水沉积的生物地球化学意义：模式-数据整合

IF 3.3 2区地球科学

Journal of Geophysical Research-Oceans Pub Date : 2025-06-25 DOI: 10.1029/2025JC022414

Stanley Nmor, Eric Viollier, Lucie Pastor, Bruno Lansard, Christophe Rabouille

{"title":"Biogeochemical Implication of Massive Episodic Flood Deposition: Model-Data Integration","authors":"Stanley Nmor, Eric Viollier, Lucie Pastor, Bruno Lansard, Christophe Rabouille","doi":"10.1029/2025JC022414","DOIUrl":"https://doi.org/10.1029/2025JC022414","url":null,"abstract":"During extreme flood events, coastal deltas experience large sediment deposition within a short time period. The biogeochemical consequences of these deposition-recycling-burial processes on carbon and nutrient cycles are not fully understood. Using a coupled data model approach, we explore the early diagenetic responses of deltaic sediments influenced by two intense floods (in spring and fall) on the Rhône River in 2008. The data set shows that sediment porewater composition responded abruptly to this almost instantaneous change in deposition. The model calculated that these flood-related depositions increased organic carbon mineralization by a factor of 2–4 compared to preflood levels, and were dominated by sulfate reduction (68%), and methanogenesis (16%). The two floods (organic-poor in spring and organic-rich in fall) cause different diagenetic effects in terms of dissolved inorganic carbon (DIC) fluxes—the 30-cm organic-poor flood deposition induced a large storage of DIC in porewaters, which largely decreased its flux to the water column, whereas the 10-cm organic-rich sediment induced a large efflux of DIC. The model reveals the absence of dissolved sulfide in porewaters after flood deposition due to iron bound precipitation. The sequential flood depositions caused a temporary memory effect (i.e., interaction between two successive floods), with stronger effect for methane (38%), whose longer relaxation timescale limits complete recovery before the next event separated by 6 months. Increasing the frequency and intensity of these events in the future could lead to memory accumulation of flood biogeochemical signatures.","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 6","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025JC022414","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144473230","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}

引用次数: 0