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Development and evaluation of an eddy-rich northwestern Pacific nested ocean model configuration (NWPAC10)
No full textOceanic variability in the Northwestern Pacific is shaped by the regional aspects of the marginal seas with influences from the western boundary currents and is also closely linked to modes of global climate variability, such as El Niño/Southern Oscillation and changes in the tropical warm pool. Therefore, the simulations of upper-ocean variability and its connection to the large-scale ocean must be effectively incorporated into ocean models for more reliable climate projections. Here, we present an eddy-resolving (1/10°) nested ocean configuration for the Northwestern Pacific region interactive with the global ocean, namely NWPAC10 (Northwestern Pacific 1/10°). The ocean component is NEMO4.2 with a global horizontal resolution of 0.5 (ORCA05) and applies the two-way nesting method AGRIF for the Northwestern Pacific region (105E–180, 0–65N); the vertical grid is described by 46 z-star levels. We evaluate the model performance by comparison with observational data. Preliminary results will be presented, including key climate variables and the upper ocean state, such as sea surface temperature and its seasonal-to-interannual variability in the Northwestern Pacific region.1
Sensitivity analysis of drag coefficient and length scale of wind influence on tropical cyclone intensity change using net energy gain rate
No full textPredicting tropical cyclones (TC) rapid intensification (RI) is one of the most significant challenges. This study refines the Net Energy Gain Rate (NGR) metric to improve TC intensity predictions, focusing on uncertainties in the drag coefficient (Cd) at extreme wind speeds and the effective length scale of TC-induced momentum transfer to the ocean (Rw). Using data from the western North Pacific basin (2004–2021), we conducted sensitivity analyses with four Cd parameterizations (increasing, decreasing, constant, and control) and varied Rw from 0.5 to 4 times the radius of maximum wind (Rmax). Results indicate that Rw=1Rmax consistently yields the highest correlation coefficient between NGR and intensity change in 24-hour among all combinations, especially for strong TCs (Category 3 or higher). Among the Cd parameterizations, the scenario where Cd decreases at wind speeds exceeding 50 m s-1 showed superior performance in capturing intensity changes. Multi-linear regression models incorporating NGR, prior 12-hour intensity changes, and vertical wind shear confirmed that decreasing Cd at Rw=1Rmax provides the most reliable predictions, achieving the highest prediction performance in the TC intensity change in 24-hour. These findings underscore the importance of accurately representing Cd behavior under extreme wind conditions and precisely defining Rw to enhance the predictive skill of NGR-based TC intensity forecasts.11Ysciescopu
Antiviral agent containing microalgae extract as an effective ingredient
No full text본 발명은 해양미세조류(Tetraselmis sp.) 추출물을 유효성분으로 포함하는 지카바이러스 감염 예방 및 치료용 조성물에 관한 것으로, 해양미세조류(Tetraselmis sp.) 추출물은 지카바이러스에 대한 감염 억제 활성이 우수하고, 바이러스 감염에 의한 염증 인자 (TNFa, IFIT1, IFIT2)에 대한 발현 조절 효능이 우수하므로, 지카바이러스 감염의 예방 또는 치료를 위한 약학 조성물, 건강기능식품 및 의약외품으로 유용하게 활용될 수 있다
Origins and pathways of the floating Sargassum in the Yellow and East China Seas
No full textUsing particle tracking modeling, the origins and pathways of floating Sargassum horneri reaching southwestern Korea were investigated. Sargassum that originated from both the Zhejiang coast of China and the northern Yellow Sea (YS) could reach Korea. Sargassum released from Zhejiang between November and February reaches Korea via the Kuroshio Current in about five months. Sargassum from the northern YS moves southward due to the northwesterly winter monsoon. In years with strong anomalous westerly winds, the floating Sargassum could reach Korea within two months. In other years, Sargassum continued to move southward toward the central East China Sea (ECS) and then to southwestern Korea in three to five months. Comparisons with the Geostationary Ocean Colour Imager showed that Sargassum found in the central ECS was mainly of northern origin. Global warming must have enhanced the northern origin to trigger the recent Sargassum blooms in the central ECS.11Nsciescopu
AUTOMATED DETACHABLE TYPE SUCTION ANCHOR SYSTEM USING CLAMP APPARATURS
No full text석션파일을 석션, 인발하기 위한 밸브, 밸브팩, 클램프 등이 프레임 내에 일체로 패키지화되어 구비된 것
으로, 시스템과 석션파일의 자동 착탈이 원활하게 이루어질 수 있고, 자동 착탈식 석션앵커 시스템이 컴팩
트화되어 운용이 용이하게 이루어질 수 있는 특징이 있다
Paleoceanographic condition changes in the Eastern Bransfield Basin, Antarctic Peninsula, since the late glacial interval and its implications
No full textAntarctic Peninsula is the most northerly area in the Antarctica, thus it is vulnerable to warming climate. Although it is well known that relatively warm water mass input onto the Antarctic shelf region facilitates ice shelf retreat, when and how the water mass exchange between the deep Southern Ocean and the Antarctic shelf regions is not well known in ice proximal areas due to sea ice dynamics on the continental shelf region. Here, we document the diatom assemblage record of a sediment core with high sedimentation rates since the late glacial interval from 34.6 ka to address surface environmental changes in the Eastern Bransfield Basin (EBB). We found that the EBB was covered by extensive sea ice showing millennial-scale variations during the late glacial interval. The sea ice started to decrease during the deglacial interval (19–11 ka) with slight increases of open ocean influence. In addition, meltwater input was significant during 14.7–11.3 ka which corresponds to Antarctic Ice Sheet Discharge events reported in the Scotia Sea including Meltwater pulse 1A and 1B. During the Holocene after 9 ka, relatively warm water mass input distinctively increased into the EBB contemporaneous with a remarkable decrease in sea ice influence indicating the strong relationship between sea ice and warm water mass input. In addition, meltwater input at 9 ka was also distinctive in the EBB, but there was no corresponding Antarctic Ice Sheet Discharge event in the Scotia Sea. Our results show how well surface environmental changes in the EBB correspond to the global climate change and the regional climatic characteristics at the same time.11Nsciescopu
S-ORS_201804_WAVE_SP
No full textThe S-ORS_201804_WAVE_SP dataset contains directional wave spectra collected by the MIROS Wave and Current Radar (MWR), a remote sensing wave observing equipment at the Socheongcho Ocean Research Station (S-ORS) in the Yellow Sea (37.4231°N 124.7381°E). The MWR system employs six antennas to sequentially observe approaching and receding waves across six sections spaced at 30-degree intervals to generate a spectrum for each section. Each section is sampled for 128 s (256 samples at a rate of 2 Hz), resulting in a single complete wave spectrum derived from approximately 13 min (128 × 6 s) of observing the waves. The dataset includes two types: raw directional wave spectra and processed directional wave spectra with optimal filter applied (Phillips Check, Long Period Noise Removal, and Energy Level Check; Jun et al., 2020).
- Period: 2018.04.01. - 2018.04.30.
- Location: 37.4231°N 124.7381°E
- Variable: Frequency, Direction, Raw Spectra, Filtered Spectr
Impacts of seasonal hypoxia on geochemistry, organic carbon oxidation, and nutrient release in the sediment of a semi-enclosed bay
No full textThe spatial extent of hypoxia in Jinhae Bay has increased over the last four decades posing a threat to benthic ecosystems and aquaculture production. To assess the effect of seasonal hypoxia on sediment biogeochemical cycles in Jinhae Bay, benthic fluxes—dissolved inorganic carbon (DIC), total alkalinity (TA), and nutrients—were measured at stations H (hypoxia) and C (control) using an autonomous in-situ benthic chamber in April, June, September, and December 2023. The combination of seasonal stratification and dissolved oxygen consumption in the sediment caused hypoxia in bottom water layers, leading to a substantial accumulation of metabolites (NH4+, PO43−, and HS−) in the pore water in June and September. The rates of organic carbon oxidation (OCox) in the sediment showed a positive correlation with chlorophyll-a (Chl-a) concentrations in the surface sediment, indicating that labile organic material can stimulate OCox. The low dissolved oxygen (DO) concentration in bottom water layers and higher anaerobic OCox at station H promoted the release of benthic nutrients with tight benthic-pelagic coupling. This research highlights the significant effects of hypoxia on sedimentary carbon, sulfur, nitrogen, and phosphate in coastal waters, which is essential for managing the environmental consequences of hypoxia in coastal environments worldwide.11Nsciescopu
기계학습을 이용한 반폐쇄형 하구에서의 탁도 분포 예측
No full text반폐쇄형 하구에서의 퇴적물 거동은 담수 방류와 해수의 상호작용에 의해 복잡한 역학적 특성을 보이며, 조석 변동과 인위적 방류가 혼합과 성층을 반복적으로 발생시키면서 탁도 변화를 유발한다. 본 연구에서는 YODA profiler와 ADCP를 활용한 Moving Vessel Profiling (MVP) 관측 기법을 이용하여 약 2년간 총 20회의 측선 관측으로부터 획득한 유속, 밀도, 용존산소, 엽록소-a 등의 하구 환경 변수들을 입력으로 활용하여 응답 변수인 탁도를 예측하는 다층 퍼셉트론 신경망(MLP-NN)을 구축하였다. 학습 네트워크는 일련의 성능 검증을 거친 후, 학습에 활용하지 않은 시기의 탁도 예측에 적용하였다. 그 결과, 조석 변동에 따른 퇴적물의 침강 및 재부유 특성을 성공적으로 재현하였으며, 특히 낙조 및 창조 시기의 경압성(baroclinic) 및 순압성(barotropic) 흐름에 의한 퇴적물 거동 특성이 공간적으로 잘 재현이 되었음을 확인하였다. 반면, 측선 관측 기간 동안 발생한 준설 작업과 같은 인위적 요인으로 인해 일부 지역에서는 예측 정확도가 다소 저하되는 경향을 보였다.2
DUAL HYBRID TURBINE SYSTEM FOR TIDAL CURRENT ENERGY CONVERTER
No full text본 발명의 일 실시예에 따른 조류 발전용 듀얼 하이브리드 터빈 시스템은 상호 이격하여 배치된 터빈부를 포함하는 터빈 시스템으로, 터빈부는 상하로 수직하게 연장 형성된 출력축과, 출력축의 외면에서 외측방향으로 연장된 블레이드 연결부재와, 블레이드 연결부재의 단부에 배치된 외측 블레이드와, 출력축의 외면에 배치되는 내측 블레이드를 포함한다.
본 발명에 따른 조류 발전용 듀얼 하이브리드 터빈 시스템은 외측 블레이드와 내측 블레이드를 이용하여 조류의 유속변화에도 발전기에 부하 변동을 최소화하여 효과적인 발전을 수행할 수 있는 효과가 있다