Journal of Geophysical Research-Oceans最新文献_第6页

Processes That Influence Bottom Temperatures in the California Current System

IF 3.3 2区地球科学

Journal of Geophysical Research-Oceans Pub Date : 2025-03-03 DOI: 10.1029/2024JC021886

M. A. Alexander, J. D. Scott, M. G. Jacox, D. J. Amaya, L. M. Wilczynski

{"title":"Processes That Influence Bottom Temperatures in the California Current System","authors":"M. A. Alexander, J. D. Scott, M. G. Jacox, D. J. Amaya, L. M. Wilczynski","doi":"10.1029/2024JC021886","DOIUrl":"https://doi.org/10.1029/2024JC021886","url":null,"abstract":"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.","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}

引用次数: 0

Groundwater Hydrodynamic Oscillations From Swash With Transparent Sand (GHOSTS)

IF 3.3 2区地球科学

Journal of Geophysical Research-Oceans Pub Date : 2025-03-03 DOI: 10.1029/2024JC021293

Delaney M. Benoit, Marie-Pierre C. Delisle, Greg Siemens, Britt Raubenheimer, Steve Elgar, Ryan P. Mulligan

{"title":"Groundwater Hydrodynamic Oscillations From Swash With Transparent Sand (GHOSTS)","authors":"Delaney M. Benoit, Marie-Pierre C. Delisle, Greg Siemens, Britt Raubenheimer, Steve Elgar, Ryan P. Mulligan","doi":"10.1029/2024JC021293","DOIUrl":"https://doi.org/10.1029/2024JC021293","url":null,"abstract":"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.","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}

引用次数: 0

Intense Frazil Ice Production Promotes High Algal Biomass in Newly-Formed Sea Ice

IF 3.3 2区地球科学

Journal of Geophysical Research-Oceans Pub Date : 2025-03-01 DOI: 10.1029/2024JC021689

Masato Ito, Keigo D. Takahashi, Ryosuke Makabe, Daisuke Hirano, Kay I. Ohshima, Takeshi Tamura, Shigeru Aoki

{"title":"Intense Frazil Ice Production Promotes High Algal Biomass in Newly-Formed Sea Ice","authors":"Masato Ito, Keigo D. Takahashi, Ryosuke Makabe, Daisuke Hirano, Kay I. Ohshima, Takeshi Tamura, Shigeru Aoki","doi":"10.1029/2024JC021689","DOIUrl":"https://doi.org/10.1029/2024JC021689","url":null,"abstract":"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 a 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 a 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 Fragilariopsis curta 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 a 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.","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}

引用次数: 0

Driving Factors of Dimethylated Sulfur Compounds in the Pearl River Estuary and Its Adjacent Coastal Waters: The Nonnegligible Role of Synechococcus

IF 3.3 2区地球科学

Journal of Geophysical Research-Oceans Pub Date : 2025-02-28 DOI: 10.1029/2024JC021764

Xu-xu Gao, Jun-feng Chen, Xing Zhai, Qian Liu, Lian-bao Zhang, Yu-bin Hu, Ming-hao Zhu, Ye-ping Liu, Xiao-bo Zhao, Xue-ming Zhu, Gui-peng Yang, Ji-Hua Liu

{"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, Jun-feng Chen, Xing Zhai, Qian Liu, Lian-bao Zhang, Yu-bin Hu, Ming-hao Zhu, Ye-ping Liu, Xiao-bo Zhao, Xue-ming Zhu, Gui-peng Yang, Ji-Hua Liu","doi":"10.1029/2024JC021764","DOIUrl":"https://doi.org/10.1029/2024JC021764","url":null,"abstract":"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-a, 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 Synechococcus, in DSCs production. The abundance of Synechococcus exhibited significant positive correlations with DMS and DMSP, compared with eukaryotic phytoplankton. These results indicated that Synechococcus may be an essential biological factor driving DSCs production in estuaries. Overall, this study provides new insights to clarify the nonnegligible role of Synechococcus in the biogenic sulfur cycle, in which its contribution must be explored in greater detail in future studies.","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}

引用次数: 0

Influence of Melt Ponds and Floe Size on Apparent Optical Properties of Sea Ice: An Idealized Modelling Investigation

IF 3.3 2区地球科学

Journal of Geophysical Research-Oceans Pub Date : 2025-02-28 DOI: 10.1029/2024JC021434

H. Zhang, M. Yu, P. Lu, M. Leppäranta, B. Cheng, J. Zhou, Q. Wang, X. Li, Z. Li

{"title":"Influence of Melt Ponds and Floe Size on Apparent Optical Properties of Sea Ice: An Idealized Modelling Investigation","authors":"H. Zhang, M. Yu, P. Lu, M. Leppäranta, B. Cheng, J. Zhou, Q. Wang, X. Li, Z. Li","doi":"10.1029/2024JC021434","DOIUrl":"https://doi.org/10.1029/2024JC021434","url":null,"abstract":"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 (αline, Tline) to the values in the MC model (α, T), Kα = αline/α, and KT = Tline/T, respectively. Due to the lateral transmittance, Kα, KT ≥ 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 Kα and KT 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.","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}

引用次数: 0

Impacts of Coastal Nutrient Increases on the Marine Ecosystem in the East China Sea During 1982–2012: A Coupled Hydrodynamic-Ecological Modeling Study

IF 3.3 2区地球科学

Journal of Geophysical Research-Oceans Pub Date : 2025-02-27 DOI: 10.1029/2024JC021553

Zhen Fang, Tian Feng, Yanjiahui Meng, Shuyu Zhao, Gang Yang, Yumiao Wang, Lihua Wang, Shuyao Shao, Weiwei Sun

{"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, Tian Feng, Yanjiahui Meng, Shuyu Zhao, Gang Yang, Yumiao Wang, Lihua Wang, Shuyao Shao, Weiwei Sun","doi":"10.1029/2024JC021553","DOIUrl":"https://doi.org/10.1029/2024JC021553","url":null,"abstract":"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.","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}

引用次数: 0

Compound Minor Floods and the Role of Discharge in the Delaware River Estuary 特拉华河河口的复合小洪水和排放的作用

IF 3.3 2区地球科学

Journal of Geophysical Research-Oceans Pub Date : 2025-02-26 DOI: 10.1029/2024JC021716

Kelly McKeon, Christopher G. Piecuch

{"title":"Compound Minor Floods and the Role of Discharge in the Delaware River Estuary","authors":"Kelly McKeon, Christopher G. Piecuch","doi":"10.1029/2024JC021716","DOIUrl":"https://doi.org/10.1029/2024JC021716","url":null,"abstract":"Compound floods are often thought of as large, infrequent floods during which extremes of coastal sea level and/or river flow combine with each other or additional factors (e.g., tides and rainfall) to induce major flooding. However, little is known about the potentially compound nature of more frequent, lower-level floods. Here, we introduce the term “compound minor floods” to define minor floods composed of two or more water-level sources. We use the Delaware River Estuary as a case study to investigate the prevalence and composition of these minor compound floods along the extent of a tidal river. We apply multiple linear regression to a 22-year time series of coastal water levels and river discharge to establish the contributions of tides, nontidal open-ocean effects, and river discharge to minor flood events at eight locations along the tidal Delaware River. We find that most minor flood events are compound in nature, requiring at least two components (e.g., tides and river discharge) to initiate flooding. We identify spatial structure in the relative importance of oceanographic and riverine contributions to minor flooding along the tidal reach of the estuary. These results suggest that incorporating fluvial components into minor flooding assessments is important to fully characterize flood risk along tidal rivers and estuaries.","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JC021716","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143489959","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

Dynamics of Surface Cold Patch off the Korean Peninsula Cape: Driven by Upwelling

IF 3.3 2区地球科学

Journal of Geophysical Research-Oceans Pub Date : 2025-02-26 DOI: 10.1029/2024JC021965

Jiachen Zhang, Hao Huang, Xueen Chen, Zhen Gao, Chunxin Yuan, Zheen Zhang

{"title":"Dynamics of Surface Cold Patch off the Korean Peninsula Cape: Driven by Upwelling","authors":"Jiachen Zhang, Hao Huang, Xueen Chen, Zhen Gao, Chunxin Yuan, Zheen Zhang","doi":"10.1029/2024JC021965","DOIUrl":"https://doi.org/10.1029/2024JC021965","url":null,"abstract":"Surface cold patches (SCPs) are important hydrological phenomena in the Yellow Sea (YS). We investigate the dynamics behind the appearance of the SCP off the Korean Peninsula Cape during summer. The numerical model results revealed that upwelling is the primary mechanism of SCP formation in this region. On one hand, the 3D vorticity balance of the dynamic processes of the SCP indicated that the combined effect of the tides and the baroclinic pressure gradient enhances dissipation in the bottom boundary layer, leading to seawater convergence in the bottom layer west of the tidal front and divergence east of the tidal front, forming a stable frontal secondary circulation and resulting in the formation of upwelling. On the other hand, the offshore transport, which is triggered by the Jeju Warm Current and persists throughout the year in the strait, leads to a divergence of seawater within the region. The joint effect of the above two processes ultimately contributes to the generation of upwelling. The presence of upwelling forces the thermocline to be changed. Strong tidal upwelling triggers the upward ventilating of the thermocline, which can bring cold water to the surface, and the dome-like upwarp of the thermocline isotherms caused by the current-induced upwelling, together lead to the formation of the SCP.","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143489958","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

Asymmetric Changes of the Subtropical Gyre Circulation and Associated Sea Level Over 1960–2018 in the Pacific Ocean 1960-2018 年太平洋副热带环流及相关海平面的非对称变化

IF 3.3 2区地球科学

Journal of Geophysical Research-Oceans Pub Date : 2025-02-26 DOI: 10.1029/2024JC021785

Ruhui Huang, Xuebin Zhang, John A. Church, Jianyu Hu

{"title":"Asymmetric Changes of the Subtropical Gyre Circulation and Associated Sea Level Over 1960–2018 in the Pacific Ocean","authors":"Ruhui Huang, Xuebin Zhang, John A. Church, Jianyu Hu","doi":"10.1029/2024JC021785","DOIUrl":"https://doi.org/10.1029/2024JC021785","url":null,"abstract":"Ocean circulations and sea level are undergoing long-term changes as part of anthropogenic global warming. Understanding these changes through the water column is important for comprehending the ocean's response to climate change. This study employs regional dynamic height (RDH) referenced to a no-motion layer (2,000 m) as a proxy to diagnose ocean circulations and sea levels using four observation-based datasets and 11 Ocean Model Intercomparison Project Phase 2 model simulations spanning from 1960 to 2018. Ocean Model Intercomparison Project Phase 2 simulations reproduce the major changes in ocean circulation indicated by observations, although regional differences are present, with certain regions exhibiting higher or lower RDH trends. North Pacific subtropical gyre shows positive RDH trends in the upper 400 m without a clear poleward shift but negative trends (spins down) below ∼400 m, while the South Pacific subtropical gyre shows positive RDH trends from surface to the no-motion layer and undergoes a poleward shift. These asymmetrical RDH trends between the North and South Pacific, are dominated by thermosteric components. The wind stress curl trends drive most changes of ocean circulations, resulting in asymmetric dynamic topography rise. Continued global warming in the 21st century is anticipated to intensify the asymmetric development of subtropical gyre circulations and associated sea levels in the Pacific Ocean.","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143489957","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

Tsunami Variability for the 2021 Megathrust and 2023 Outer Rise MW 7.7 Earthquakes Southeast of the Loyalty Islands

IF 3.3 2区地球科学

Journal of Geophysical Research-Oceans Pub Date : 2025-02-26 DOI: 10.1029/2024JC021880

William H. Robert, Yoshiki Yamazaki, Kwok Fai Cheung, Thorne Lay

{"title":"Tsunami Variability for the 2021 Megathrust and 2023 Outer Rise MW 7.7 Earthquakes Southeast of the Loyalty Islands","authors":"William H. Robert, Yoshiki Yamazaki, Kwok Fai Cheung, Thorne Lay","doi":"10.1029/2024JC021880","DOIUrl":"https://doi.org/10.1029/2024JC021880","url":null,"abstract":"The 2021 shallow plate-boundary thrust-faulting and 2023 outer rise normal-faulting MW 7.7 earthquakes southeast of the Loyalty Islands produced significant, well-recorded tsunamis around the North and South Fiji Basins. The two earthquakes occurred in close proximity on opposing sides of the Southern Vanuatu Trench with similar seismic moments and east-west rupture lengths but different faulting mechanisms. This provides a basis to examine tsunami sensitivity to source geometry and location for paths in the complex southwest Pacific region. Finite-fault models of the source processes for both events were inverted from teleseismic body wave data with constraints from forward, nonhydrostatic modeling of regional tide gauge and seafloor pressure sensor recordings. The wave motions are reversed in sign, with a leading crest generated by 1.31 m uplift on the upper plate slope for the 2021 tsunami and a leading trough from 2.37 m subsidence on the subducting plate near the trench for the 2023 tsunami. The more recent outer rise normal faulting produces narrower seafloor deformation beneath deeper water resulting in shorter period tsunami waves that shoal and refract more effectively along seamounts and island chains to produce a more elaborate radiation pattern. The source location relative to seamounts and small islands in the near field influences the energy lobes and directionality of the far-field tsunami to the north. In contrast, both events have very similar radiation patterns to the south due to absence of major bathymetric features immediately southward of the sources.","PeriodicalId":54340,"journal":{"name":"Journal of Geophysical Research-Oceans","volume":"130 3","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143489999","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