Search Results (141)

This study investigates the relationship between ground heat flux (GHF) over the Tibetan Plateau and heatwave days in Korea. A weak negative correlation was found during the pre-1998 period (1979 to 1997), whereas a strong positive correlation emerged during the post period (1998 to 2019). To further examine the mechanisms underlying this interdecadal change, seven positive and seven negative GHF years were selected for both the pre-1998 and post-1998 periods and composite analyses were conducted. During positive GHF years in the post-1998 period, the Tibetan Plateau experienced enhanced surface heating, reduced spring snow cover, and lower summer soil moisture. These conditions favored greater absorption and release of heat from the land surface. Concurrently, anomalous anticyclonic circulation strengthened throughout the troposphere, accompanied by enhanced subsidence over the latitude band containing the Korean Peninsula. In addition, both the western North Pacific high and the South Asian high expanded and intensified during positive GHF years, exerting a stronger influence on the middle and upper troposphere over Korea. The increased occurrence of heatwaves in Korea during the post-1998 period is partly attributable to enhanced thermal forcing over the Tibetan Plateau and the associated development of a circumglobal teleconnection-like wave train, which induced downstream anticyclonic circulation anomalies over East Asia. This upper-tropospheric forcing, together with a La Niña–like or negative Pacific Decadal Oscillation–like sea surface temperature pattern, created atmospheric conditions favorable for more frequent heatwave events over Korea. These results suggest that the influence of Tibetan Plateau thermal forcing on Korean heatwaves has strengthened since the late 1990s through its interaction with large-scale atmospheric circulation and oceanic background conditions. Full article

Education for sustainability should connect planetary environmental change with local place, cultural meaning, and feasible collective action. Yet inclusive arts-based ocean-literacy education remains underexamined, especially for children from migrant backgrounds. This study examines Gyeongju Sea Rescue Team: Protecting the Sea through Minhwa, a five-session programme for elementary-school children from Koryoin and other migrant-background families in South Korea. A provenance-separated dual-strand design combined hybrid thematic analysis of programme documents and non-identifying artwork images with a fully synthetic 100-case corpus used only to audit a future artwork-elicitation protocol and codebook. The documentary strand identified four provisional mechanisms: the ecological reinterpretation of auspicious symbols, localisation through Gyeongju’s maritime heritage, multimodal participation across linguistic differences, and collective stewardship. The synthetic audit did not validate these mechanisms or programme outcomes. Instead, participant-correction and self-action prompts generated more clearly codable material on agency, cultural identity, multilingual meaning-making, and intercultural integration. Two designed perturbation passes yielded a quadratic-weighted kappa of 0.726 as a within-corpus stability diagnostic rather than human intercoder reliability. Diagnostic cases exposed adult projection, assimilationist interpretation, pressure to disclose private meanings, and advice without self-agency. The article proposes a provisional MIOL framework and four safeguards: child-led interpretation, reciprocal cultural exchange, appropriate consent and permissions, and continuity from symbolic expression to sustained action. Synthetic outputs concern method development only and do not represent children’s experiences or programme effectiveness. Full article

Evaluating the sealing integrity of caprocks is critical for ensuring the long-term safety and containment efficiency of geological hydrocarbon reservoirs and CO₂ storage systems. In this study, we evaluated the caprock sealing capacity of the South Sea continental shelf using drill cutting samples collected from six wells across four structural blocks. Representative caprock intervals, consisting primarily of fine-grained sedimentary rocks, were identified based on well data and lithofacies information. Mercury Injection Capillary Pressure (MICP) analyses were performed to characterize pore structure and capillary sealing behavior. Results indicate that nanopores (<1 μm) dominate the pore system; however, pore size distributions exhibit significant heterogeneity. While B well samples displayed unimodal nanopore distributions, other wells showed bimodal or broad multiscale structures. As a result, MICP-derived Hg-air breakthrough pressures (P_b) varied considerably, ranging from 75 to 283 MPa. Notably, samples G-1 and J5-4 exhibited sealing capacities capable of retaining CO₂ column heights exceeding 5052 m, whereas sample J1-1 showed the lowest sealing performance. In the B well, a clear depth-dependent trend was observed: as depth increased from 2480 m to 3685 m, the critical pore diameter decreased from 13.66 nm to 7.57 nm, and breakthrough pressure increased from 95 MPa to 171 MPa. Subsequent quantitative XRD analysis, corrected for drilling-induced contamination, revealed that these deeper intervals are characterized by clay-rich (50.85–63.19%) and relatively ductile mineralogical compositions. These findings suggest that burial-related compaction within a consistently clay-rich, relatively ductile matrix may contribute to pore-throat refinement and enhanced relative capillary sealing capacity in the B well. Overall, the caprocks of the South Sea continental shelf show significant potential for geological hydrocarbon and CO₂ storage, though the observed spatial and depth-dependent heterogeneity underscores the necessity of well-specific site characterization. Full article

The effective closure of the Strait of Hormuz on 28 February 2026 disrupted approximately 20 million barrels (bbl) per day of crude oil transit, constituting the largest supply shock in global oil market history. This study quantifies the resulting economic losses under three blockade-duration scenarios and evaluates the Northern Sea Route (NSR) as a partial mitigation mechanism through a novel framework integrating sustainable supply chain resilience (SSCR), the Triple Bottom Line (TBL), and the United Nations Sustainable Development Goals (SDGs). A 3 × 3 scenario matrix crossing three blockade durations with three NSR utilization levels estimates global and country-level impacts using data from the International Energy Agency (IEA), the International Monetary Fund (IMF), and the Centre for High North Logistics (CHNL). Even under maximum feasible NSR utilization, net environmentally adjustment mitigation offsets only 1.1–3.6% of total global losses, demonstrating that the Northern Sea Route functions as marginal insurance rather than a viable substitute for Hormuz-dependent supply chains. Global Gross Domestic Product (GDP) losses range from USD 330 billion to USD 2.2 trillion, with South Korea (68–70% Middle East crude dependency) and Japan (approximately 95%) disproportionately affected. After TBL environmentally adjustment monetizing CO₂, black-carbon, and icebreaker costs, the NSR mitigates 1.1–3.6% of total losses, functioning as insurance rather than substitution. The SDG assessment reveals a fundamental trade-off: the NSR offsets energy-security losses (SDGs 7, 9) but worsens climate and marine outcomes (SDGs 13, 14). Theoretically, this study proposes “alternative maritime route availability” as a conceptual extension of supply chain resilience (SCRes) capabilities and outlines a sustainability-adjusted resilience score (SARS) framework that, pending further validation, could serve as a replicable assessment tool. These findings underscore that accelerating the energy transition remains the most effective long-term response to chokepoint vulnerability. Full article

Shellfish aquaculture can alter sediment conditions and affect benthic ecosystem functioning, so dredging is widely applied as a management strategy to mitigate sediment deterioration. However, its ecological effectiveness remains uncertain. This study evaluated ecological quality under the disturbance of dredging in shellfish farming areas of Gamak Bay, South Korea, using multiple macrobenthic indices. Macrobenthic samples and environmental data were collected before (May 2025) and after dredging (August 2025). Five macrobenthic indices, including the AZTI Marine Biotic Index (AMBI), BENTIX, Benthic Polychaete/Amphipod ratio (BPA), Benthic Pollution Index (BPI), and Multivariate AMBI (M-AMBI), along with a composite index, were used to assess ecological quality. Temporal changes within groups were tested using Wilcoxon signed-rank tests, and differences between dredged and control stations were examined using Mann–Whitney U tests. Multivariate analyses were used to explore environmental gradients and community responses. Results showed clear seasonal variation in environmental conditions and macrobenthic community structure. Most indices indicated a decline in ecological quality after dredging, with higher AMBI values and lower BENTIX, BPI, and M-AMBI values at dredged stations. However, these changes were not statistically significant (p > 0.05), suggesting limited short-term effects of dredging. The proportion of stations with acceptable ecological status decreased slightly from May to August. Seasonal factors, particularly temperature and salinity, played a dominant role in structuring benthic communities. Overall, the findings indicate that the short-term dredging effects were weaker than seasonal environmental variability. A multi-index approach is recommended for robust ecological assessment, and long-term monitoring is necessary to fully evaluate the effectiveness of dredging in shellfish aquaculture systems. Full article

The influence of station-to-station line orientation on sea current speed observations using Coastal Acoustic Tomography (CAT) was quantitatively investigated. For this purpose, we conducted CAT experiments at five stations in Yeosu Bay, South Korea. Through these experiments, the sea current speeds were estimated along a total of six tomographic observation lines with different orientations, and the results were compared with current speeds measured simultaneously by an Acoustic Doppler Current Profiler (ADCP). The comparison showed that the concordance between tomography-estimated sea current speed and ADCP-measured sea current speed tended to decrease as the acute angle between the predominant tidal current direction in Yeosu Bay and a tomographic observation line increased. This tendency is interpreted as arising because the smaller the difference between the two one-way travel times obtained during tomographic observations, the greater the effect of the travel time measurement error whose magnitude is relatively direction-independent. This interpretation was supported by a simple numerical simulation. Furthermore, quantitative analysis of these simulation results indicated that a smaller acute angle between the predominant sea current direction in the survey area and a tomographic observation line enhances the robustness of sea current speed estimation against travel time measurement errors. The results show that the station-to-station line in CAT should be arranged considering the predominant sea current direction in the survey area, which can provide an important guideline for selecting station locations. Full article

Advanced time series interpolation techniques used for estimating marine environmental factors encounter challenges regarding their usability, practical implementation, and reproducibility outside of marine science laboratories. This study aimed to interpolate NIFS Serial Oceanographic Observations and develop a system for analyzing complex factors in offshore and coastal fishing ground formation in South Korea. Additionally, the study explored the potential for integration of spatiotemporally discontinuous in situ data with continuously available satellite data through interpolation methods. Specifically, daily sea temperature and salinity data were generated through conventional time series interpolation techniques such as linear, cubic spline, and STL + PCHIP, and spatial interpolation techniques such as IDW, kriging, and natural neighbor were used to construct monthly raster data. The generated data were compared with the output of the GOFS3.1 model, and statistical indices such as MAE, RMSE, R², and Pearson or Spearman correlation coefficients were used to evaluate the accuracy and reproducibility. Cubic spline temporal and kriging spatial interpolation methods demonstrated strong performance for the sea temperature data; however, the interpolation performance for the salinity data exhibited limited effectiveness owing to unique local variability. This study introduces techniques for transforming discontinuous in situ observational data into high-resolution data and demonstrates that the integrated use of in situ data can enhance our understanding of the fishing ground formation mechanisms and ecosystem-based fishery management. Full article

In this study, the stomach contents of the crocodile toothfish Champsodon snyderi from the offshore waters of the South Sea of Korea were analyzed to understand their feeding characteristics. Bottom-trawlers in the South Sea of Korea were used to collect a total of 228 C. snyderi individuals with lengths ranging from 3.6 cm to 12.3 cm. Based on the index of relative importance and variations in the stomach contents according to fish size, C. snyderi was identified as a spatiotemporal opportunistic feeder that consumes abundant prey resources in the South Sea of Korea. Although no distinct dietary shift was observed with growth, there was a decreasing and increasing trend in the proportion of amphipods and shrimp consumed, respectively, in association with increasing C. snyderi body size in the nearshore waters of the South Sea of Korea. In addition, differences in the stomach content composition were observed in relation to interactions between season and size. Our findings indicate that the feeding characteristics of C. snyderi are affected by the abundance and composition of prey within its habitat. Full article

This study investigated the site-specific ionic composition and wet deposition loads of rainwater collected from eight actively cultivated agricultural regions across South Korea, with the aim of quantifying spatial and seasonal variability and interpreting how regional agricultural characteristics and surrounding site conditions influence major ion concentrations and deposition patterns. Rainfall samples were obtained using automated samplers and analyzed via high-performance ion chromatography for major cations (Na⁺, $\mathrm{N}{\mathrm{H}}_4^{+}$, K⁺, Ca²⁺, Mg²⁺) and anions (Cl⁻, $\mathrm{N}{\mathrm{O}}_3^{-}$, $\mathrm{S}{\mathrm{O}}_4^{2-}$, $\mathrm{N}{\mathrm{O}}_2^{-}$). The results revealed significant seasonal fluctuations in ion loads, with $\mathrm{N}{\mathrm{H}}_4^{+}$ (peak 1.13 kg/ha) and K⁺ (peak 0.25 kg/ha) reaching their highest levels during summer due to increased fertilizer use and crop activity. Conversely, Cl⁻ peaked in winter (2.11 kg/ha in December), particularly in coastal regions, likely influenced by de-icing salts and sea-salt aerosols. Correlation analysis showed a strong positive association among $\mathrm{N}{\mathrm{H}}_4^{+}$, $\mathrm{N}{\mathrm{O}}_3^{-}$, and $\mathrm{S}{\mathrm{O}}_4^{2-}$ (r = 0.89 and r = 0.84, respectively), indicating shared atmospheric transformation pathways from agricultural emissions. Ternary diagram analysis further revealed regional distinctions: coastal regions such as Gimhae and Muan exhibited Na⁺ and Cl⁻ dominance, while inland areas like Danyang and Hongcheon showed higher proportions of Ca²⁺ and Mg²⁺, reflecting differences in aerosol sources, land use, and local meteorological conditions. These findings underscore the complex interactions between agricultural practices, atmospheric processes, and local geography in shaping rainwater chemistry. The study provides quantitative baseline data for evaluating non-point source pollution and developing region-specific nutrient and soil management strategies in agricultural ecosystems. Full article

Microplastic distribution off the coast of Korea was investigated by collecting and analyzing surface seawater and sediment samples from the South Sea and East China Sea during the summer. Microplastic abundance was found to be highest in the YE area, followed by the EC area and the SS area in both seawater and sediment matrices. The dominant microplastic shapes and sizes were fragments and small particles (0.02–0.3 mm), respectively. This distribution pattern is explained by the transport of low-density, small-sized microplastics from other seas via the high salinity Taiwan Warm Current and Tsushima Warm Current flowing northward from the southern waters of the study area. In contrast, microplastics originating from the Korean landmass along the southern coast were less abundant, likely due to their dispersal by the strong currents of the Jeju Warm Current, Taiwan Warm Current, and Tsushima Warm Current, which carry microplastics toward the Korean Strait. This study highlights the critical role of prevailing ocean currents in shaping the spatial distribution of microplastics, providing insight into sources and transport mechanisms relevant for regional marine pollution management in the Korean coastal waters. Full article

Sebastes thompsoni is a cold-water rockfish of commercial and ecological value off the coast of Korea, requiring conservation management. We analyzed seven microsatellite loci to assess genetic diversity, population structure, and historical effective population size (N_e) of five populations obtained from the South and East Seas of Korea in 2018. The observed heterozygosity (H_O = 0.759–0.816) was higher than previously reported, and none of the STRUCTURE, DAPC, or AMOVA analyses detected geographic differentiation among samples from the South and East coasts of Korea, indicating a single population within these coasts. There was genetic flow between the five groups, with migration rates ranging from 4.1 to 19.11. However, the current N_e of all populations is estimated to be <1000, and VarEff-based reconstructions indicate a recent, severe bottleneck following an expansion approximately 600–1200 years ago (100–200 generations ago). This suggests that genetic diversity loss may persist in the future due to long-term habitat loss, fishing pressure, and ocean current fluctuations. Therefore, S. thompsoni should be established as a single management unit covering the Korean Peninsula coast, and habitat protection, overfishing control, genetic management type resource release using various mother and broodstock, and periodic genetic monitoring should be promoted. This study provides evidence to guide efforts to secure long-term genetic resilience and sustainable management of S. thompsoni in Korean coastal waters. Full article

Biofouling on offshore wind farm substructures threatens operational reliability and raises maintenance demands, underscoring the need for effective antifouling strategies. This study presents a 27-month evaluation of fouling development on a conventional non-antifouling coating and self-polishing copolymer (SPC) systems at a South Korean offshore wind farm. Biofouling coverage was assessed through long-term image analysis, and surface energy was characterized via contact angle measurements. Species analyses identified successional communities dominated by barnacles, coralline algae, and bryozoa. The conventional coating showed rapid colonization, exceeding 90% coverage within 10 months, whereas the SPC systems exhibited superior performance by suppressing settlement, though their effectiveness declined over time. Quantitative analysis revealed a clear relationship between higher surface energy and increased fouling rates, highlighting material properties as a key factor in colonization. This study provides one of the first long-term quantitative datasets from South Korean waters, advancing understanding of biofouling dynamics and informing antifouling strategies for offshore wind infrastructure. Full article

The waters surrounding the Five West Sea Islands of South Korea are ecologically important but challenging to survey due to their location within a strategic military zone, strong tidal currents, and significant tidal variation. To assess the fish community in this region, we conducted Korea’s first parallel investigation combining traditional bottom trawl surveys with environmental DNA (eDNA) metabarcoding. Sampling was performed at 10 stations in March, May, and August 2023, and the relationship between fish species occurrence and environmental variables (water temperature, salinity, and depth) was examined. Dominant trawl-caught species included Engraulis japonicus, Johnius grypotus, Coilia nasus, and Okamejei kenojei, each showing seasonal migration and spawning patterns associated with temperature changes. eDNA analysis detected nine additional species absent from trawl catches, such as Ilisha elongata and Thamnaconus modestus, demonstrating its sensitivity in identifying both migratory and sedentary taxa. Our findings confirm that eDNA surveys can complement traditional sampling, improving biodiversity assessment in regions with limited accessibility and complex oceanographic conditions. Full article

This study examined the spatial distribution and environmental determinants of hairtail (Trichiurus lepturus) catch volumes in the southern coastal waters of South Korea, employing a Spatial Durbin Model (SDM) based on grid-level data collected from 2020 to 2022. Key explanatory variables included chlorophyll-a concentration, dissolved oxygen, salinity, sea surface temperature, and fishing effort. Spatial autocorrelation was confirmed through Moran’s I test, justifying the application of a spatial econometric framework. Among the environmental factors, salinity exhibited the strongest positive direct effect on catch volumes, whereas dissolved oxygen consistently showed a negative effect. Chlorophyll-a concentration exhibited significant positive effects both within local grids and in neighboring areas. Sea surface temperature also had a modest but significant direct effect on catch volumes. Additionally, higher fishing effort was associated with increased catch volumes, emphasizing the spatial impact of human activities on fishery resources. These findings reveal that hairtail tend to aggregate in high-salinity, low-oxygen environments and respond to seasonal oceanographic variations. Overall, the results highlight the value of spatial econometric models in fisheries research by revealing how environmental and anthropogenic factors influence fish catch through both direct and indirect effects. The spatial framework offers deeper insight into the mechanisms driving hairtail distribution, particularly in ecologically complex regions like the Jeju Strait. Full article

The Marine Pollution Control Act (MPCA) in Taiwan aims to align with international conventions such as the United Nations Convention on the Law of the Sea (UNCLOS), the International Convention for the Prevention of Pollution from Ships (MARPOL), the International Convention on Civil Liability for Oil Pollution Damage (CLC), the International Oil Pollution Compensation Funds (FUNDs), and the International Convention for the Control and Management of Ships’ Ballast Water and Sediments (BWM). However, Taiwan’s particular international status prevents formal participation in these treaties. This study evaluates Taiwan’s legal and institutional frameworks on ship emission control, pollution liability and compensation, and interagency coordination, identifying key gaps compared with global standards. By analyzing Japan’s and South Korea’s best practices in port management, cross-border pollution prevention, and vessel monitoring, this study proposes legal and policy reforms that are tailored to Taiwan. Recommendations include strengthening liability mechanisms, enhancing interagency collaboration, monitoring vessels, and fostering regional cooperation. Our findings suggest that these reforms will improve Taiwan’s marine environmental governance and contribute to regional and global ocean sustainability. Full article