• Title/Summary/Keyword: Coastal Circulation

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A Numerical Experiments on the Atmospheric Circulation over a Complex terrain around Coastal Area. Part I : A Verification of Proprietyh of Local Circulation Model Using the Linear Theory (연안부근 복잡지형의 대기유동장 수치실험 I -선형이론을 이용한 국지순환모형의 타당성 검토-)

  • 이화운;김유근;정우식
    • Journal of Environmental Science International
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    • v.8 no.5
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    • pp.555-558
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    • 1999
  • A sea/land breeze circulation system and a regional scale circulation system are formed at a region which has complex terrain around coastal area and affect to the dispersion and advection of air pollutants. Therefore, it is important that atmospheric circulation model should be well designed for the simulation of regional dispersion of air pollutants. For this, Local Circulation Model, LCM which has an ability of high resolution is used. To verify the propriety of a LCM, we compared the simulation result of LCM with an exact solution of a linear theory over a simple topography. Since they presented almost the same value and pattern of a vertical velocity at the level of 1 km, we had a reliance of a LCM. For the prediction of dispersion and advection of air pollutants, the wind filed should be calculated with high accuracy. A numerical simulation using LCM will provide more accurate results over a complex terrain around coastal area.

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A Numerical Analysis of Regional Atmospheric Circulation with Large Scale Reclamation of Coastal Region (대규모 해안매립에 따른 기상장 변동의 수치해석)

  • 이성대
    • Journal of Ocean Engineering and Technology
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    • v.14 no.3
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    • pp.46-54
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    • 2000
  • Three dimensional numerical experiments that included the land-use transformation by the large scale reclamation were used to investigate the mesoscale air flow over the coastal regions. In this paper the surface temperature of the inland was determined through the surface heat budget consideration with inclusion of a layer of vegetation. The vertical diffusion coefficients of momentum, heat and specific humidity in the constant flux layer were taken from the Mellor and Yamada(1975). It has shown that the resulting model is able to reproduce the air circulation in coastal regions, and the simulated characteristics agree with the known properties of this circulation. A series of numerical experiments were then carried out to investigate the diurnal response of the air flow to various types of surface inhomogeneities.

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Circulations in Coastal Areas off South China

  • Ye, Longfei
    • Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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    • 1995.10a
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    • pp.62-65
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    • 1995
  • Understanding the flow circulation is of primary importance for studies of marine ecology and Pollution protection etc. However the circulation in coastal area is complicated with various processes and can not be considered as forced only by tides. The coastal area off South China is now playing an important role in economic development in southeast Asia with Hong Kong, Macao, Guangzhou and other cities situated in its central part (Fig. 1). (omitted)

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A Study of Atmospheric Field around the Pohang for Dispersion Analysis of Air Pollutants -Numerical Simulation of Wind Field- (대기오염 확산 해석을 위한 포항지역 기상장 연구 -바람장 수치모의-)

  • 이화운;정우식;김현구;이순환
    • Journal of Korean Society for Atmospheric Environment
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    • v.20 no.1
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    • pp.1-15
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    • 2004
  • Sea/land circulation system is a representative mesoscale local circulation system in coastal area. In this study, wind fields around coastal area. Pohang, which is affected by this system was investigated and its detailed characteristic analysis was carried out. The following can be found out from the numerical simulation. Generally, at nighttime mountain winds prevail and land breeze toward the coastal area was well simulated During daytime, valley wind and sea breeze was simulated in detail. Especially, as a result of analyzing the land breeze path, it could be found along the coastline as it flows out through low land coastal area. In order to investigate the accuracy of model results. wind speed, temperature and wind direction of continuous typical sea/land breeze occurrence day was compared with observation data. Analyzing the characteristics of local circulation system was very hard because of horizontally sparse observation data but from the above result, a numerical simulation using RAMS, which satisfies the spatial high resolution, will provide more accurate results.

Numerical Analysis of Wind Driven Current and Mesoscale Air Flow in Coastal Region with Land Topography (육상지형을 고려한 연안해역에서의 중규모 기상장과 취송류에 관한 수치해석)

  • Lee, Seong-Dae
    • Journal of Ocean Engineering and Technology
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    • v.20 no.5 s.72
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    • pp.23-29
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    • 2006
  • A quasi depth-varying mathematical model for wind-generated circulation in coastal areas, expressed in terms of the depth-averaged horizontal velocity components and free surface elevation was validated and used to understand the diurnal circulation process. The wind velocity is considered as a dominant factor for driving the current. In this paper, three-dimensional numerical experiments that included the land topography were used to investigate the mesoscale air flaw over the coastal regions. The surface temperature of the inland area was determined through a surface heat budget consideration with the inclusion of a layer of vegetation.A series of numerical experiments were then carried out to investigate the diurnal response of the air flaw and wind-generated circulation to various types of surface inhomogeneities.

The Characteristics of Circulation in the Coastal Area of Jeju Harbor Using the Three Dimensional Ocean Circulation Model (3차원 해수유동모델에 의한 제주항 연안해역의 해수순환 특성)

  • Yang, Tai-Hoek;Yang, Sung-Kee
    • Journal of Environmental Science International
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    • v.20 no.6
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    • pp.679-686
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    • 2011
  • The characteristics of circulation in the coastal area of Jeju Harbor in Korea was examined using the Princeton Ocean Model(POM) with a sigma coordinate system. The result of numerical analysis well corresponded to the observed current data. The velocity at offshore was stronger compared to coastal area during the both period of in maximum flood and maximum ebb of spring tide. According to mean wind velocity, the tidal velocity at the shallow area of Jocheon was slightly increasing during maximum ebb. The effect of wind on the circulation was stronger in shallow area and showed rapid change with depth.

Study On The Coastal Cold Water Near Ulsan

  • Lee, Ki-Baik
    • 한국해양학회지
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    • v.13 no.2
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    • pp.5-10
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    • 1978
  • The coastal cold water near Ulsan, Korea, almost always appears in summer. From the results of some data analysis, it is found that this cold water has an important relation to the anticlockwise circulation appearing near the coast where the anticlockwise circulation turns its current direction from south to east.

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A Nested OGCM Simulations with Restart Dataset --Strategy for Simulating Fine Structures of Circulation for NW Pacific

  • Park, Byung-Ho;Wei Zexun;Guohong Fang;Park, Young-Jin
    • Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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    • 2000.09a
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    • pp.182-187
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    • 2000
  • Laboratory for Coastal and Ocean Dynamics Studies at Sungkyunkwan University and Department of Physical Oceanography, Institute of Oceanology, Chinese Academy of Sciences has been working on cooperative studies on ocean circulation. (omitted)

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A Case Study on Sea Breeze Circulation and Ozone Concentration due to the Effect of Cold Water in the Southeastern Coastal Area of Korea (한국 남동연안의 냉수대 영향에 의한 해풍순환과 오존농도의 사례연구)

  • Ji, Hyo Eun;Lee, Soon-Hwan;Park, Changhyoun;Lee, Hwa Woon
    • Journal of Environmental Science International
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    • v.23 no.2
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    • pp.261-274
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    • 2014
  • This work investigates the relationship between the sea breeze circulation and ozone concentrations during cold water events in the southeastern coastal area of the Korean Peninsula, where coastal upwelling frequently occur. This analysis was performed based on the classification of two categories, such as cold water and non-cold water events, over the period of 2000-2009. The low air temperature ($0.5^{\circ}C$), low SST ($5^{\circ}C$) and the wind direction(southerly) are the features of the cold water events in the Southeastern coastal area. Moreover, ozone concentrations in the cases of the sea breeze circulation and cold water events were significantly lower (below 30 ppb) than those (70~100 ppb) in the non-clod water events, because of the low air temperature ($10{\sim}20^{\circ}C$) and high wind speed (3~5 m/s) around the southeastern coastal area.

Wind-Driven Circulation Using a Curvilinear Hydrodynamic Three-Dimensional Model (곡선형격자 삼차원 수치모형을 이용한 바람에 의한 물의 순환)

  • Lee, Hye-Keun
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.6 no.1
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    • pp.1-11
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    • 1994
  • A curvilinear hydrodynamic three-dimensional model is presented for the study of wind-driven circulation in a shallow lake. Numerical results are compared with field data. Thermal stratification effects were found to be critical to the successful simulation of circulation under increasing winds. When there ate insufficient meteorological data, the so-called inverse method can be used for the estimation of heat flux.

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