Estuarine Coastal and Shelf Science最新文献

{"title":"Spatiotemporal patterns and environmental drivers of Physalia physalis strandings along mainland Portugal (northeastern Atlantic)","authors":"Patrícia Carvalho ,&nbsp;Clara Cordeiro ,&nbsp;Soraia Pereira ,&nbsp;Antonina dos Santos","doi":"10.1016/j.ecss.2025.109674","DOIUrl":"10.1016/j.ecss.2025.109674","url":null,"abstract":"<div><div><em>Physalia physalis</em> is a cosmopolitan colonial organism frequently observed in Portuguese waters. The species has long tentacles, provided with cnidocytes, which release a strong poison when in contact with other organisms, and cause skin reactions and severe pain in humans. Events of rapid reproduction, common in these species, may have important economic and social consequences. This study explores for the first time, the relationships between long-term assessment of <em>P. physalis</em> strandings, using data from the GelAvista citizen science project, and environmental variables - Sea Surface Temperature (SST), wind direction and intensity, the North Atlantic Oscillation (NAO), and upwelling indices - along the Portuguese coast, using a Generalized Linear Mixed-Effects Model.</div><div>Strandings of <em>P. physalis</em> were concentrated along the western coast and were rare in the south. More than 54 % of the records corresponded to a single individual. Sightings peaked from November through May (winter and spring), mirroring the negative correlation with SST. Wind patterns strongly influenced stranding events: winds likely pushed colonies toward the shore, while calm conditions facilitated their arrival on beaches. In March 2018, an upwelling event in the south coast combined with a series of storms likely underlay the high stranding numbers observed in the southern area, with more than 50 individuals of <em>P. physalis</em> per record.</div><div>A positive trend in sightings over the study period suggests that <em>P. physalis</em> occurrences may be rising, even after accounting for wind and SST, which might be linked to climate change. Our findings underscore the value of ongoing jellyfish monitoring via citizen science platforms like GelAvista and highlight the need for expanded high-resolution environmental datasets. Moreover, this work establishes a foundation for experimental studies to elucidate the mechanisms behind <em>P. physalis</em> strandings. For future research, time series techniques for imputing missing values may be utilized to enhance the completeness of environmental datasets and strengthen analytical robustness in subsequent studies focused on time series analysis.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"329 ","pages":"Article 109674"},"PeriodicalIF":2.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145840009","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":"“Groundwater and ferromanganese oxide-coated calcareous concretion release excess radon to the southwestern Yellow Sea”","authors":"Shibin Zhao ,&nbsp;Qingzhen Yao ,&nbsp;Disong Yang ,&nbsp;Xiaoyi Guo ,&nbsp;Chunqian Li ,&nbsp;Wen Liu ,&nbsp;Yuan Lu ,&nbsp;Zhigang Yu ,&nbsp;Bochao Xu","doi":"10.1016/j.ecss.2025.109664","DOIUrl":"10.1016/j.ecss.2025.109664","url":null,"abstract":"<div><div>As a natural-occurring radioisotope, radon (²²²Rn, <em>t</em>_1/2 = 3.82 d) is generally enriched in groundwater than surface water, which has been routinely applied to trace submarine groundwater discharge (SGD) process in coastal regions. However, the high ²²²Rn content in coastal seawater may not always be attributed to SGD solely, especially when encountering with specific sedimentary sources on the seafloor. In this study, we systematically investigated the radon distribution in water columns in the southwestern Yellow Sea. Highest ²²²Rn activity (reaching ∼280 Bq m⁻³) appeared in coastal bottom seawaters between 119.5–120.5°E along the 35°N transect, which were 2−4 times of that in surface waters under stratified condition. The excess ²²²Rn are likely attributed to bottom-up mechanisms. By combining laboratorial incubation, gamma spectrometry and laser-induced breakdown spectroscopy measurements, we found the widespread ferromanganese oxide-coated calcareous concretions on the seafloor can extract ²²⁶Ra from seawater, resulting in a radon diffusional flux ∼3 times greater than surrounding sandy/muddy sediments. Total SGD flux and water residence time in the southwestern Yellow Sea were solved through the radon-radium mass balances and Monte Carlo simulation approaches, which were 1.1 (0.6–2.0) × 10⁹ m³ d⁻¹ or 0.078 (0.042–0.14) m d⁻¹ and ∼35 days. SGD played the dominating role (58.6 %–69.9 %) in controlling radon inventory in water bodies under stratified condition, followed by diffusion from sedimentary sources (20.5 %–31.2 %) and parent ²²⁶Ra production (9.3 %–10.5 %). Our findings highlight the radium enrichment mechanism of Fe/Mn oxide-rich concretion may be overlooked in radon-based tracer studies, potentially compromising the accuracy of SGD quantification.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"329 ","pages":"Article 109664"},"PeriodicalIF":2.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145737153","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":"Significant dissolved nutrient and carbon via fresh and saline groundwater discharge into a mariculture bay","authors":"Huiying Li ,&nbsp;Fenfen Zhang ,&nbsp;Jinzhou Du ,&nbsp;Jianan Liu","doi":"10.1016/j.ecss.2025.109655","DOIUrl":"10.1016/j.ecss.2025.109655","url":null,"abstract":"<div><div>Submarine groundwater discharge (SGD) is a critical pathway for transporting nutrient and carbon from land to coastal ecosystems, yet its partitioning into fresh SGD (SFGD) and recirculated seawater (RSGD) and associated solute fluxes remain poorly constrained in mariculture bays. In this study, we quantified different types of SGD and their derived dissolved nutrient and carbon fluxes in Xihu Bay, a typical mariculture-dominated semi-enclosed bay in Zhejiang, China, using a²²⁴Ra mass balance model combined with water-salt mass balance model. Results showed total SGD flux reached (2.5 ± 0.7) × 10⁷ m³ d⁻¹ (46 ± 12 cm d⁻¹), with SFGD contributing 3.5 % of the total SGD flux but only 1.6–7.5 % of SGD-derived nutrient fluxes (dissolved inorganic nitrogen: 136 ± 88 μmol m⁻² d⁻¹; dissolved inorganic phosphorous: 1.8 ± 0.60 μmol m⁻² d⁻¹; dissolved inorganic silicon: 89 ± 25 μmol m⁻² d⁻¹) and &lt;8 % of carbon fluxes (dissolved inorganic carbon: 1352 ± 419 μmol m⁻² d⁻¹; dissolved organic carbon: 6.3 ± 2.6 μmol m⁻² d⁻¹). In contrast, RSGD dominated both dissolved nutrient (92.5–98.4 %) and carbon (&gt;92 %) transporting, driven by tidal pumping and wave. With high nitrogen to phosphorous ratios in SFGD (54.5) and RSGD (77.9), it may exacerbate nutrient stoichiometric imbalance in Xihu Bay. Elevated nutrient and carbon concentrations in saline groundwater, highlighted RSGD as a key carrier of anthropogenically derived solutes. Given the absence of riverine inputs, SGD emerged as the predominant external source of nutrient and carbon, emphasizing its critical role in regulating biogeochemical cycles and ecological dynamics in aquaculture-impacted bays.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"329 ","pages":"Article 109655"},"PeriodicalIF":2.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145737624","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":"Bivariate extreme analysis for coastal flooding in the Adriatic Sea","authors":"Sara Corvaro,&nbsp;Francesco Marini,&nbsp;Stefania Rocchi,&nbsp;Carlo Lorenzoni","doi":"10.1016/j.ecss.2025.109668","DOIUrl":"10.1016/j.ecss.2025.109668","url":null,"abstract":"<div><div>This study investigates the interaction between storm surge and wave height in the Adriatic Sea, focusing on their combined joint influence on coastal flooding risk under different climate scenarios and return periods. Using bivariate statistical analysis based on measured data (water levels) and hindcast data (significant wave heights), the research quantifies the joint probabilities of extreme storm events and highlights the contribution of waves (wave set-up) in amplifying extreme sea levels (ESLs) in the coastal area. In particular, the study aims to assess extreme sea levels in the Adriatic Sea by providing ESLs maps for different return periods and two IPPC climate change scenarios (SSP1-1.9 and SSP5-8.5). Maximum ESLs are observed in the northern Adriatic, with Venice identified as a hotspot. Wave contributions are shown to substantially double water levels, particularly in the areas between Ancona and Zadar and near the southern entrance at Otranto, emphasizing the need for a bivariate approach to accurately capture these interactions. The projected sea level rise further exacerbates the risks posed by storm events, particularly for vulnerable coastal areas. The present study underscores the need for a more comprehensive understanding of the combined joint effects of storm surge and waves, and enable more effective coastal flooding risk assessments along the Adriatic coast due to extreme sea levels by providing valuable support for designing mitigation measures to address climate-driven extreme events.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"329 ","pages":"Article 109668"},"PeriodicalIF":2.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145790349","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":"Spatiotemporal variability in the biochemical characteristics of phytoplankton and zooplankton in the coastal waters of the Yellow and East seas","authors":"Da Won Goh ,&nbsp;Min Ho Seo ,&nbsp;Young Seok Jeong ,&nbsp;Jun Sik Woo ,&nbsp;Sanghoon Park ,&nbsp;JaeSoon Kim ,&nbsp;Myung Joon Kim ,&nbsp;Yoon Ji Lee ,&nbsp;Ye Hwi Kim ,&nbsp;Ha Young Choi ,&nbsp;Hye Min Choi ,&nbsp;Sang Heon Lee","doi":"10.1016/j.ecss.2025.109681","DOIUrl":"10.1016/j.ecss.2025.109681","url":null,"abstract":"<div><div>The coastal waters are dynamic ecosystems influenced by seasonal temperature fluctuations, riverine inputs, and upwelling, which drive sensitive responses among lower trophic-level organisms. The biochemical composition of phytoplankton and zooplankton plays a critical role in determining energy flow and food web structure, yet their spatiotemporal variability remains underexplored. This study investigated spatiotemporal variability in the biochemical composition of phytoplankton and zooplankton in the Yellow Sea (YS) and East Sea (ES), focusing on environmental and biological drivers. Field surveys were conducted in spring (May) and summer (August) of 2023 (YS) and 2024 (ES), quantifying phytoplankton macromolecular composition—carbohydrates (CHO), proteins (PRT), and lipids (LIP)—and zooplankton proximate composition (PRT, LIP, and ash), and various environmental parameters. In the YS, phytoplankton LIP content was negatively correlated with nutrient concentrations, suggesting nutrient-driven biochemical shifts. In the ES, phytoplankton exhibited significant seasonal changes, with PRT decreasing and CHO increasing, reflecting metabolic adaptation to temperature stress and nutrient limitation. Zooplankton biochemical composition reflected these regional contrasts: in the YS, variability was largely influenced by community structure, while in the ES, it was more strongly regulated by phytoplankton nutritional quality. Under nutrient-limited conditions, diatom growth slows and cell wall synthesis may increase frustule thickness. These changes could reduce food palatability, which may help explain the observed pattern in the ES, including decreased zooplankton PRT content and increased LIP storage. A positive correlation in PRT content between phytoplankton and zooplankton in the ES indicated a stronger biochemical trophic linkage under stable copepod dominance, whereas weakened coupling in the YS reflected grazer diversity and variable feeding selectivity. These findings highlight how environmental conditions and community composition regulate biochemical properties and trophic connectivity in Korean coastal marine ecosystems.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"329 ","pages":"Article 109681"},"PeriodicalIF":2.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145884472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of the Congo River plume and tropical upwelling on Sardinella spawning in the southeastern Atlantic","authors":"Maik Tiedemann ,&nbsp;Marek Ostrowski ,&nbsp;Miguel Andre António ,&nbsp;Domingas N'saku ,&nbsp;Roy Dorgeless Ngakala ,&nbsp;Jens-Otto Krakstad ,&nbsp;Øystein Skagseth ,&nbsp;Stamatina Isari","doi":"10.1016/j.ecss.2025.109651","DOIUrl":"10.1016/j.ecss.2025.109651","url":null,"abstract":"<div><div>The Congo River releases nutrient-rich freshwater into the southeastern Atlantic, forming a plume that fuels regional productivity sustaining small pelagic fish such as <em>Sardinella</em> (<em>Sardinella aurita</em> and <em>Sardinella maderensis</em>). However, the impact of the plume on <em>Sardinella</em> reproduction is still uncertain. A survey conducted in austral summer 2014, coinciding with the Congo River secondary seasonal discharge peak and tropical upwelling, provided evidence on how riverine runoff and upwelling jointly influence <em>Sardinella</em> spawning. Congo River discharge was prominent along the coast, with low-salinity, high-chlorophyll surface waters spreading north- and northwestward. Spawning was observed north of the Congo River mouth, with the peak confined to the plume region, as also corroborated by generalized additive models. Wind and ocean current patterns suggested a northwest drift of ichthyoplankton trapped within the plume, with offshore loss near southern Gabon. A Lagrangian drift simulation aligned with these observation pathways. Plume dynamics were absent along the Angolan coast, where the tropical upwelling seemed the sole driver of coastal productivity. No <em>Sardinella</em> eggs were observed there, but larvae were distributed, aligned with the upwelling front signatures. Our findings underscore the Congo River plume as a key spawning habitat for <em>Sardinella</em> during austral summer. Higher spawning activity within the plume likely suggests that its physical and biogeochemical conditions are more favourable than adjacent upwelling zones. The study highlights the need to consider riverine influences alongside upwelling dynamics in understanding and managing small pelagic fish populations in tropical marine ecosystems.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"329 ","pages":"Article 109651"},"PeriodicalIF":2.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145839944","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":"Ciliate grazing control of a spring bloom in a temperate fjord","authors":"Laia Armengol ,&nbsp;Lumi Haraguchi ,&nbsp;Marta Moyano ,&nbsp;Santiago Hernández-León ,&nbsp;Hans H. Jakobsen","doi":"10.1016/j.ecss.2025.109631","DOIUrl":"10.1016/j.ecss.2025.109631","url":null,"abstract":"<div><div>Plankton communities underpin marine ecosystem functioning, yet the mechanisms driving the onset and termination of spring phytoplankton blooms are not fully understood. In particular, the role of microzooplankton grazing and the impact of mixotrophic versus heterotrophic ciliates on phytoplankton dynamics. This study aimed to quantify ciliate grazing and phytoplankton growth rates throughout a spring bloom in Roskilde Fjord, Denmark; and determine whether nutrient depletion or microzooplankton grazing was the primary driver of bloom culmination. Surface water was collected during March 2017, and multiple dilution experiments were conducted to estimate phytoplankton growth and grazing mortality rates. Phytoplankton community structure was assessed by flow cytometry, while ciliate morphotypes and nutritional modes were identified using FlowCam imaging. Despite initially high nutrient concentrations, a marked decrease in DIN and DIP occurred over the study period. Phytoplankton biomass, dominated by cryptophytes, reached its peak by mid-March before declining. Concurrently, ciliate assemblages shifted from mixotrophic to heterotrophic dominance. Grazing rates frequently exceeded phytoplankton growth rates after the first experimental day, indicating strong top-down control. The lack of significant differences in growth between nutrient-amended and unamended treatments suggested grazing, rather than nutrient depletion, predominantly constrained phytoplankton accumulation. These findings highlight how ciliate grazing can exert a critical influence on spring bloom dynamics, even under moderate nutrient conditions. Understanding these trophic interactions is essential for predicting the resilience and stability of coastal marine ecosystems in the face of changing environmental conditions.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"329 ","pages":"Article 109631"},"PeriodicalIF":2.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145737150","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":"Severe wave events and long-term variations in wind wave climate in the Gulf of Gdańsk during 1958–2001","authors":"Witold Cieślikiewicz ,&nbsp;Aleksandra Cupiał","doi":"10.1016/j.ecss.2025.109658","DOIUrl":"10.1016/j.ecss.2025.109658","url":null,"abstract":"<div><div>Severe wind wave events are characteristic of the Gulf of Gdańsk (southern Baltic Sea). Hence, this study analyses a 44-year (1958–2001) WAM-modelled wind wave dataset for the Gulf of Gdańsk based on the NCEP reanalysis within the EU-funded HIPOCAS project. Temporal variability of wind wave parameters was assessed at five distinct locations in the Gulf to assess the spatial differences. Weak linear trends were detected in the mean, maximum, and 99th percentile of significant wave height in some of the selected areas. An increase in mean wave heights during the 1980s and 1990s, followed by a decline at the end of the century was observed, particularly in the open part of the Gulf. Variations in the mean wave period largely mirrored changes in mean significant wave height but were negligible overall. A total of 34 extreme wave events were identified across the selected points in the Gulf, concentrated in the cold season (October–March). These events were unevenly distributed throughout the analysed period, with a noticeable rise in storm frequency in the late 20th century. To characterise these storm events, the pathways of associated low-pressure systems were examined. A clear relationship emerged between the spatial distribution of large waves and the low's trajectories. Two main pathways of low-pressure systems were identified: (i) systems moving eastward from the North or Norwegian Sea, across the Baltic along a W–E axis, and (ii) a less common NW-SE track from the Norwegian Sea through Scandinavia into the Baltic. To further investigate the link between storm tracks and wave evolution during individual extreme events, two idealised low-pressure trajectories (W-E and NW-SE) were modelled with concentric isobars. Their movement demonstrated how storm track orientation shapes spatial wave distribution across the Gulf, underscoring the link between cyclone pathways and wave extremes.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"329 ","pages":"Article 109658"},"PeriodicalIF":2.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145737155","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":"Widespread breaching of intermittent estuaries by atmospheric rivers: A satellite-based assessment in central-southern Chile","authors":"Raúl P. Flores ,&nbsp;Óscar Milla ,&nbsp;Martina Monasterio ,&nbsp;Carlos Lara ,&nbsp;Isabel Caballero","doi":"10.1016/j.ecss.2025.109663","DOIUrl":"10.1016/j.ecss.2025.109663","url":null,"abstract":"<div><div>Small estuaries and coastal lagoons, which are common in Mediterranean climates such as California, Australia and central Chile, are ecologically important systems that can alternate between open (ocean-connected) and closed states depending on the balance between river discharge and wave-driven sediment transport. Under drought conditions, these systems can remain closed for extended periods, which alters hydrodynamic, sedimentary, and ecological processes. This study examines the response of small intermittent estuarine systems to two atmospheric river (AR) events that impacted central Chile in 2023, delivering extreme precipitation, sharp increases in river discharge, and widespread flooding. Using high-resolution satellite imagery and open-source image processing algorithms, we tracked the state of 176 river mouths between 32°S and 38°S, documenting breaching and subsequent closure in the following months. Our results show that the vast majority of river mouths and coastal lagoons re-established connectivity with the ocean after the ARs, including several that had remained closed for multiple years. Subsequent inlet closures followed a clear north-to-south latitudinal progression, consistent with the transition to wetter climates. Analysis of river discharge and inlet width revealed a strong correlation for Andean-fed rivers with sustained baseflows, while this link was weaker for small coastal rivers that were closed prior to the ARs. The combined analysis of river discharge, wave forcing and inlet state data suggests a nonlinear response in which the timing and sequencing of fluvial and wave forcings govern inlet state transitions. Overall, our findings demonstrate that ARs, which are projected to increase in frequency, can rapidly reset coastal morphology and temporarily restore ocean connectivity in drought-impacted Mediterranean-type coasts.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"329 ","pages":"Article 109663"},"PeriodicalIF":2.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145737152","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 reversible eddy as a driver of thermal fronts in the Northern Gulf of California","authors":"Amelia Sánchez-Pérez ,&nbsp;Laura Sánchez-Velasco ,&nbsp;Emmanuel Romero","doi":"10.1016/j.ecss.2025.109653","DOIUrl":"10.1016/j.ecss.2025.109653","url":null,"abstract":"<div><div>In semi-enclosed seas, circulation plays a key role in the formation of thermal fronts by regulating the distribution of waters with distinct properties. Using 20 years of satellite and ocean reanalysis temperature data, this study examines the seasonal distribution of thermal fronts in the Upper and Northern Gulf of California and their relationship with regional circulation. Thermal fronts were detected from the surface to 300 m depth using temperature gradients, and their intensity and Front Probability Index were used to generate seasonal and monthly climatologies. Results reveal a strong seasonal variability dominated by the seasonal reversible eddy, cyclonic in summer and anticyclonic in winter, that drives the formation and intensity of thermal fronts. On the surface of the Northern Gulf, maximum probability occurred in June in the northeast, associated with a strong northerly coastal current, and in August in the southwest, due to cyclonic eddy circulation. These fronts extended to 100 m depth with maximum intensity at 50 m, corresponding with the eddy core depth. In the Upper Gulf, the highest probabilities were detected at the surface in spring and fall, influenced by circulation changes characteristic of these transitional periods. These findings demonstrate that circulation is a driver in the formation of thermal fronts. Their persistence, despite variations in intensity and position, contributes to the productivity of this semi-enclosed sea, as is also the case in other semi-enclosed seas.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"329 ","pages":"Article 109653"},"PeriodicalIF":2.6,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145737622","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}