• Title/Summary/Keyword: land-land breeze

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An Investigation of Elementary Students' Perception and Inferring Process about a Land and Sea Breeze (해륙풍에 대한 초등학생의 이해 및 추리과정 조사)

  • Hyun, Dong-geul;Kang, Won-mi;Lim, Sung-man;Chae, Dong-hyun
    • Journal of Science Education
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    • v.38 no.1
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    • pp.160-167
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    • 2014
  • A land and sea breeze and the cause of wind are learned through a convection current box experiment in elementary science class. The purpose of this study was to investigate elementary students' perception and inferring process about a land and sea breeze. For this purpose, the 159 elementary students who lived in J city were collected. The results of this study showed that the students who perceived correctly about a land and sea breeze and the cause of wind were only 45 persons(28.3%). And most of the students understood the direction of the wind as they observed in the experiment. That is, most of the students did not understand a direction of a land and sea breeze by a inferring process from the experimental result. They did not pass by a inferring process. These results demand that a new convection current box experimental set is to be developed, as well as the experimental instruction more focused on the inferring process, for the perception of a land and sea breeze and the cause of wind.

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The Effect of Inversion Layer on the Land and Sea Breeze Circulations near the Gangneung (역전층이 강릉시 주변 해륙풍 순환에 미치는 영향 연구)

  • NamGung, Ji-Yeon;Yu, Jae-Hoon;Kim, Nam-Won;Choi, Man-Kyu;Ham, Dong-Ju;Kim, Hoon-Sang;Jang, You-Jung;Choi, Eun-Kyung
    • Atmosphere
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    • v.15 no.4
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    • pp.229-239
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    • 2005
  • The effect of inversion layer on the land and sea breeze near the Gangneung city was investigated. The land and sea breeze occurrence days were selected, and the height and the intensity of inversion layer were calculated with the upper air observational data of the Sokcho Station. The relationships between the temperature variation near the Gangneung and the inflow time, inland penetration and the inflow depth of the land and sea breeze were also analyzed. And the Gangwon Short-range prediction system was verified with the comparison of surface stream line by the Gangwon short-range prediction system with the AWS wind vector data. It was revealed that the inversion layer tended to block the sea breeze, shorten the inland penetration distance and lower the inflow depth, causing the temperature rise. The comparison and analysis of surface steam line by the Gangwon short-range prediction system and the AWS wind vector showed that the system quite well simulated the sea breeze, thus the system could be well utilized in the prediction of land and sea breeze.

A Numerical Certification to Estimated Dimensions of the Observed Land-Sea Breeze Data (해륙풍관측 data의 차원추정 값에 대한 수치적 검증)

  • Lee Hwa-Woon;Kim Yoo-Keun;Lee Young-Gon
    • Journal of Environmental Science International
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    • v.8 no.6
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    • pp.661-667
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    • 1999
  • Estimating dimensions of attractors are the most basic tools to analyze properties of chaotical dynamic systems. In this paper, we estimate correlation dimensions of meteorological variables, such as wind speed (v) and temperature (T) observed in Kimhae International Airport when the land-sea breeze circulation is appeared and find low non-integer values that reflect the deterministic chaos characterizing the dynamics. We compare the results with the correlation dimensions of 2-dimensional model that is calculated by finite element method. Though the correlation dimensions of the calculated wind speed ( v) are less than those of the observed wind speed ( v), we can suggest that the land-sea breeze circulation has not a unique mechanism. The land-sea breeze phenomenon is a complicated dynamics, which is constructed with various scale motions of atmosphere. In further research, we hope to find more accurate dynamics of land-sea breeze through wide observations and using of more sophisticated prediction models.

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A Numerical Simulation of Air Pollutant Concentration Considering Land and Sea Breeze in Ulsan Area (해륙풍을 고려한 울산지역 대기오염물질농도의 수치모의)

  • 이화운;원경미;정우식;오은주;김민선;도우곤
    • Journal of Environmental Science International
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    • v.11 no.9
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    • pp.933-943
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    • 2002
  • The urban pollution if affected by local environmental, so it is necessary to consider area characteristics such as emission source and meteorological phenomena, in studying urban air pollution. Ulsan is laocated on south-east coast and has many industrial facilities, so many people have concerned about air pollution. This study contain conducting numerical simulation of air pollutant concentration considered land and sea breeze in Ulsan area with the numerical model.

WRF Sensitivity Experiments on the Choice of Land Cover Data for an Event of Sea Breeze Over the Yeongdong Region (영동 지역 해풍 사례를 대상으로 수행한 지면 피복 자료에 따른 WRF 모델의 민감도 분석)

  • Ha, Won-Sil;Lee, Jae Gyoo
    • Atmosphere
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    • v.21 no.4
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    • pp.373-389
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    • 2011
  • This research focuses on the sensitivity of the WRF(Weather Research and Forecasting) Model according to three different land cover data(USGS(United States Geological Survey), MODIS(Moderate Resolution Imaging Spectroradiometer)30s+USGS, and KLC (Korea Land Cover)) for an event of sea breeze, occurred over the Gangwon Yeongdong region on 13 May 2009. Based on the observation, the easterly into Gangneung, due to the sea-breeze circulation, was identified between 1000 LST and 1640 LST. It did not reach beyond the Taebaek Mountain Range and thus the easterly was not observed near Daegwallyeong. On the other hand, the numerical simulations utilizing land cover data of USGS, MODIS30s+USGS, and KLC showed easterlies beyond the Taebaek Mountain Range up to Daegwallyeong. In addition, rather different penetration distances of each easterly, and different timings of beginning and ending of sea breeze were identified among the simulations. The Bias, MAE(Mean Absolute Error) and RMSE(Root Mean Square Error) of the wind from WRF simulation using MODIS30s+USGS land cover data were the least among the simulations particularly over Gangwon Yeongdong coastal area(Sokcho, Gangneung and Donghae), while those of the wind over the Gangwon Mountain area(Daegwallyeong and Jinbu) from the simulation using KLC land cover data were the least among them. The wind field over Gangwon Yeongdong coastal area from the simulation using USGS land cover data was rather poor among them.

Estimating Correlation Dimensions of Land-Sea Breeze Phenomenon

  • Lee, Hwa-Woon;Kim, Yoo-Keun;Lee, Young-Gon
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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    • v.3 no.2
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    • pp.81-89
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    • 1999
  • This study estimates the correlation dimensions of the land-sea breeze phenomenon, that has a clear diurnal cycle, in order to gain a more detailed understanding of this phenomenon. The data adopted include north-south wind velocity component(v) and temperature(T) time series that were observed at Kimhae Airport and Inje University over a period of 5 days, from the 4th to the 8th of August, 1994. The embedding phase space of the time series were reconstructed from 2 to 14 dimensions, and the correlation dimensions of the attractors were then estimated. The results show that the land-sea breeze phenomenon exhibits a deterministic chaos with non-integer correlation dimension values between 2 and 3. Accordingly, 3 is the minimum number of independent variables required to model the dynamics of the landsea breeze phenomenon in the Kimhae area. Since the saturated embedding dimension, when the correlation dimension remains unchanged, is larger for the wind velocity v-component than for temperature, this indicates that wind velocity is susceptible to topology.

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A Study on Mesoscale Atmospheric Dispersion of Radioactive Particles Released from Nuclear Power Plants (원전부지 주변 국지순환에 따른 방사성 물질의 대기확산 특성 연구)

  • Lee, Gab-Bock;Lee, Myung-Chan;Song, Young-I1
    • Journal of Radiation Protection and Research
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    • v.22 no.4
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    • pp.273-288
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    • 1997
  • A three dimensional sea-land breeze model and Lagrangian particle dispersion model have been employed for the study on the mesoscale atmospheric dispersion of radioactive materials released from Wolsung NPPs. In this study, atmospheric dispersion simulations are carried out under two synoptic weather conditions : the geostrophic flow is a weak northerly wind(CASE 1) and a strong northerly wind(CASE 2) on a clear day in spring. The results show that atmospheric dispersion is affected by sea-land breeze and the recirculation of particles by the change of wind direction between sea breeze and land breeze plays an important role in atmospheric concentration distribution of radoactive materials.

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Numerical Simulation of Advection and Diffusion using the Local Wind Model in Kwangyang Bay, Korea (국지풍모델을 이용한 광양만권의 이류확산 수치모의)

  • ;;Akira Kondo
    • Journal of Korean Society for Atmospheric Environment
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    • v.18 no.1
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    • pp.1-10
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    • 2002
  • A three-dimensional numerical model which involved the nesting method was developed to reproduce the wind circulation of Kwangyang Bay area which comprises complicated mountains and sea topograph. The calculated results indicated geographical effects of Kwangyang Bay area, sea/land breezes and mount-valley wind which are local circular winds. We also noticed that the northern inland area of Kwangyang Bay formed the very complex wind systems under the influence of such geographic effects when a land breeze was not formed. A good agreement was found between predicted and observed values of temperature. In addition, the calculated results of the wind direction and the wind velocity are in accord with the observed values. They showed only a slight difference in between predicted and the observed values, when the sea breeze and the land breeze are changing.

Numerical Simulation of Effect of Urban Land-use Type and Anthropogenic Heat on Wind Field (지표면 변화와 인공열이 바람장에 미치는 영향에 관한 수치 시뮬레이션)

  • 홍정혜;김유근
    • Journal of Korean Society for Atmospheric Environment
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    • v.16 no.5
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    • pp.511-520
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    • 2000
  • The urban atmosphere is characterized by th difference in surface and atmospheric environment between urban and more natural area. To investigate th climatic effect of land use type and anthropogenic heat of urban on wind field, numerical simulations were carried out under typical summer synoptic condition. The wind model PNU_MCM(Pusan National University Mesoscale Circulation Model) is based on the three-dimensional Boussinesq equations, taking into account the hydrostatic assumption . Since lane-use differs over every subdivision on Pusan the surface energy budget model includes sub0grid parameterization scheme which can calculate the total heat flux over a grid surface composed of different surfaces. The simulated surface wind agrees well with the observed value, and average over 6 days which represent typical summer lan-sea breeze days, August 1998, i.e. negligible gradient winds and almost clear skies. Urbanization makes sea-breeze enhance at day and reduce land-breeze at night. The results show that contribution of land-use type is much larger than that of anthropogenic heat in Pusan.

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Numerical Simulation for Recirculation of Air Mass in the Coastal Region Using Lagrangian Particle Dispersion Model (라그랑지안 입자확산모델을 이용한 광양만 권역에서의 공기괴 재순환현상 수치모의)

  • Lee, Hwa-Woon;Lee, Hyun-Mi;Lee, Soon-Hwan;Choi, Hyun-Jung
    • Journal of Environmental Science International
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    • v.19 no.2
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    • pp.157-170
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    • 2010
  • Air mass recirculation is a common characteristic in the coastal area as a result of the land-sea breeze circulation. This study simulates the recirculation of air mass over the Gwangyang Bay using WRF-FLEXPART and offers a basic information about the effective domain size that can reflect recirculation. For this purpose, WRF is set up four nested domains and three cases are selected. Subsequently FLEXPART is operated on the basis of WRF output. During the clear summer days with weak wind speed, particles that emitted from Yeosu national industrial complex and Gwangyang iron works flow into emission sources because of the land-sea breeze. When land-sea breeze is strengthen, the recirculation phenomena appears clearly. However particles aren't recirculated under weak synoptic condition. Also plume trajectory is analyzed and as a consequence, the smallest domain area have to be multiplied by 1.3 to understand recirculated dispersion pattern of particles.