• 대기
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• 제17권3호
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• pp.241-253
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• 2007

This paper investigates summer precipitation change in East Asia according to switching surface boundary condition over South Korea and Shantung. Simulations are carried out by ECHO-G/S for 20 years (1980-1999). Surface condition over both areas in ECHO-G/S is represented by ocean (OCN experiment). In OCN experiment, the summer precipitation is considerably underestimated around the Korean peninsula (the dry region) and overestimated over the eastern Tibetan Plateau (the wet region). It may be related that the lack of the heat sources from the unrealistically prescribed land-sea mask weakens northward expansion of rainband and the development of convective precipitation. Moreover the simulated rainband retreats before June in connection with the early genesis of summer monsoon circulation. The systematic bias of the summer precipitation over the dry and wet regions are reduced comparing with the OCN experiment when the land-sea masks over South Korea and Shantung are realistically considered as land (LND experiment). These improvements can be explained by the thermodynamical dissimilarity between land and ocean. Enhanced warming by switching the areas from sea to land has led to develop the thermal low over Yellow Sea with the cyclonic circulation. Thus, this cyclonic circulation supports moistures from the south to the dry region and blocks to the wet region. The heat transport from the land surface to atmosphere plays a key role in the developing convective precipitation in local scale and maintaining the precipitation and the rainband. Therefore, this results indicate that the design of the realistic land-sea distribution is required for the accurate simulation of the regional precipitation.

• Journal of the korean society of oceanography
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• 제34권4호
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• pp.185-199
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• 1999

With a realistic geography and topography the Princeton Ocean Model is used to study the effects of topography, wind and time-varying Chanajiang (Yangtze) River discharge on the dispersion of the Chanaiiang River plume in the Yellow and East China Seas. The topographic feature of deepening offshore suppresses the offshore expansion of the discharged low salinity water while spreading along the coast is not hindered. Also the spreading of the Chanajiang River plume is very sensitive to wind conditions and the southerly wind is most responsible for the eastward expansion toward the Cheju Island. It is also shown that the influence of the Chanajiang River Diluted Water on the hydrography and circulation of the Yellow Sea including the South Sea of Korea is substantial even in the absence of tide, wind and current.

• 한국해양학회지
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• 제28권2호
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• pp.121-131
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• 1993

연구에서는 서해 중부역(태안반도 부근)에 형성되는 조석전선을 3차원 해수유동 모델(Semtner, 1974) 과 Simpson & Hunter (1974)의 혼합효율(mixing efficiency)개념 을 발전시킨 혼합을 개념을 이용하여 계산하였다. 모델을 구성하는데 있어서 모델 영 역의 남·북에 위치한 개방경계에는 간단한 radiation condition을 적용하였으며, 동 계 외양조건을 초기조건으로 하여 표층의 지속적인 열에너지 공급 및 공간적으로 상이 한 수직혼합 작용에 의해 형성되는 조석전선을 계산하였다.

• 한국해안해양공학회지
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• 제5권2호
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• pp.151-171
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• 1993

본 종설에서는 과거 20년에 걸친 동중국해와 황해의 조석수치모형에 대해 개관하였다. 조석모형 및 경험적인 조석도에 의거하여 이 해역의 조석양상에 대해 기술하였으며 이와 관련된 해저 조석소산, 조석혼합, 퇴적 및 순환에 대하여 기술하였다. 또한 조석모형에 관련된 문제점과 개선방법에 대하여 논의하였다.

• 한국군사과학기술학회지
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• 제12권1호
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• pp.29-36
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• 2009

Realtime tide and storm-surge computations for the Yellow Sea were conducted using the Parallel Finite Element Model. For these computations a high resolution grid system was constructed with a minimum node interval of loom in Gyeonggi Bay. In the modeling, eight main tidal constituents were analyzed and their results agreed well with the observed data. The realtime tide computation with the eight main tidal constituents and the storm-surge simulation for Typhoon Sarah(1959) were also conducted using parallel computing system of MPI-based LINUX clusters. The result showed a good performance in simulating Typhoon Sarah and reducing the computation time.

• 한국해양학회지
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• 제22권2호
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• pp.63-70
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• 1987

기존 해양조사 자료에 의하면 황해 동부는 일반적으로 한국연안을 따라 형성되는 조석전선으로 특징지어 진다. 황해서부에서는 이러한 조석전선이 약하게 나타나는 듯하다. 이러한 현상은 장소에 따라 그 강도가 다른 조석혼합에 기인된다 하겠다. 측정된 밀도구조에 기존 지혈調整모델을 적용한 결과연안의 혼합수는 북향, 외양의 성층수(표층 및 저층)는 남향함이 밝혀졌다. 이들 각 수괴의 수송량은 약 $10^{4}$m$^{3}$/sec로 나타났다.

• 대기
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• 제26권3호
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• pp.357-372
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• 2016

Northeast Asian regions have recently become the main source of anthropogenic and natural aerosols. Measurement of aerosols on the sea in these regions have been rarely conducted since the experimental campaigns such as ACE-ASIA (Asian Pacific Regional Aerosol Characterization Experiment) in 2001. Research vessel observations of aerosol mass and chemical composition were performed on the Yellow and south sea around the Korean peninsula. The ship measurements showed six representative cases such as aerosol event and non-event cases during the study periods. On non-event cases, the anthropogenic chemical and natural soil composition on the Yellow sea were greater than those on the south sea. On aerosol event cases such as haze, haze with dust, and dust, the measured mass concentrations of anthropogenic chemical and element compositions were clearly changed by the events. In particular, methanesulfonate ($MSA^-$, $CH_3SO_3^-$), a main component of natural oceanic aerosol important for sulfur circulation on Earth, was first observed by the vessel in Korea, and its concentration on the Yellow sea was three times that on the south sea during the study period. Sea salt concentration important to chemical composition on the sea is related to wind speed. Coefficients of determination ($R^2$) between wind speed and sea salt concentration were 0.68 in $PM_{10}$ and 0.82 in $PM_{2.5}$. Maximum wave height was not found to be correlated to the sea salt concentration. When sea-salt comes into contact with pollutants, the total sea-salt mass is reduced, i.e., a loss of $Cl^-$ concentration from NaCl, the main chemical composing sea salt, is estimated by reaction with $HNO_3$(gas) and $H_2SO_4$(gas). The $Cl^-$ concentration loss by $SO_4^{2-}$ and $NO_3^-$ more easily increased for $PM_{10}$ compared to $PM_{2.5}$. The results of this study will be applied to verifying a dust-haze forecasting model. In addition, continued vessel measurements of aerosol data will become important to research for climate change studies in the future.

• 한국해양학회지
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• 제19권2호
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• pp.187-194
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• 1984

黃海에서 水塊와 循環에 대해 간략히 檢討, 討議하였다. 水塊는 黃海冷水, 黃海溫流水, 沿岸水, 陽子江 稀釋수 네가지로 分類된다. 黃海冷水는 長技 海洋觀測資料와 최근 CTD로 資料부터 32.0~33.0%의 鹽分, 1$0^{\circ}C$이하의 水溫을 갖고 있는 것으로 定義할 수 있다. 海水循環은 南部海域에서 年中 反時計方向의 海水循環이 存在한다. 겨울철에는 中國沿岸을 따라 南向하는 沿岸流流가 北風, 北西風으로 인해 强하게 나타나며 濟州道 西部 海域에 강한 水溫.鹽分前線이 잘 보여주듯 黃海暖流는 弱해진다. 반면에 여름철에는 陽子江 釋수가 濟州道 쪽을 향해 北東쪽으로 擴張하며 中國 沿岸流가 상당히 減少하게 된다. 지금 까지 여름철 東南黃海에서 北向流를 黃海暖流로 分類하였으나 류의 延長이 아니라 沿岸水와 黃海冷水사이 境界面을 따라 形成되는 密度流로 보는 것이 더욱 妥當하다.

• 한국정보통신학회논문지
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• 제5권6호
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• pp.1190-1194
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• 2001

TOPEX/POSEIDON(T/P) 위성의 7년 간 고도계자료를 사용하여 동북아시아지역에서의 해수면 순환과 해수면 변화에 대하여 연구하였다. 헌장 조위자료와 고도계자료간의 비교에서, 고도계에 포함되어 있는 60일의 tidal aliasing(M$_2$ 및 S$_2$의 해양조석 성분)의 영향을 제거한 후 순수 해수면 성분을 구하였다. 해수면 변동을 보면 쿠로시오 해류가 사행을 하면서 강하게 흘러가는 일본 동남부해역에서 뚜렷한 와류의 형성과 함께 높은 해수면 변화 값을 보였다. 이것은 쿠로시오의 확장과 해저지형의 영향과 기인하다. 평균해수면은 황해 및 동해에 비해서 북태평양해역에서 높게 나타났다.

• Journal of the korean society of oceanography
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• 제39권1호
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• pp.57-71
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• 2004

Based on the data obtained under the China-Korea joint project (1997-2001) and historic observations, the distribution, transportation and sedimentation of sediment in the southern Yellow Sea (SYS) are discussed, and the controversial formation mechanism of muddy sediments is also explored. The sediment transport trend analysis indicates that the net transport direction of sediment in the central SYS (a fine-grained sediment deposited area) points to $123.4^{\circ}E,\;35.1^{\circ}N$, which is a possible sedimentation center in the central SYS. The sediment transport pattern is verified by the distribution of total suspended matter (TSM) concentration and ${\delta}^{13}C$ values of particulate organic carbon (POC), the latter indicates that the bottom water plays a more important role than the surface water in transporting the terrigenous material to the central deep-water area of the SYS, and the Yellow Sea circulation is an important control factor for the sediment transport pattern in the SYS. The carbon isotope signals of organic matter in sediments indicate that the Shandong subaqueous delta has high sedimentation rate and the deposited sediments originate mainly from the modern Yellow River. The terrigenous sediments in deep-water area of the SYS originate mainly from the old Yellow River and the modern Yellow River, and only a small portion originates from the modern Yangtze River. The analytical results of TSM and stable carbon isotopes are further confirmed by another independent tracer of sediment source, polycyclic aromatic hydrocarbons (PAHs). Five light mineral provinces in the SYS can be identified and they indicate inhomogeneity in sources and sedimentary environment. The modern shelf sedimentary processes in the SYS are controlled by shelf dynamic factors. The muddy depositional systems are produced in the shelf low-energy environments, which are controlled by some meso-scale cyclonic eddies (cold eddies) in the central SYS and the area southwest of the Cheju Island. On the contrary, an anticyclonic muddy depositional system (warm eddy sediment) appears in the southeast of the SYS (the area northwest of the Cheju Island). In this study, we give the cyclonic and anticyclonic eddy sedimentation patterns.