• Title/Summary/Keyword: Upper wind condition

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The Effect of Surface and Vertical Observation Data Assimilation on the Horizontal and Vertical Flow Fields Depending on the Upper Wind Conditions (종관 특성에 따른 지상 및 연직 관측자료 동화가 수평 및 연직 확산장에 미치는 영향)

  • Choi, Hyun-Jung;Lee, Hwa-Woon;Kim, Min-Jung
    • Journal of Korean Society for Atmospheric Environment
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    • v.26 no.2
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    • pp.177-189
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    • 2010
  • In order to incorporate correctly the large or local scale circulation in an atmospheric model, a nudging term is introduced into the equation of motion. The MM5 model was used to assess the meteorological values differences in each case, during ozone episode days in Gwangyang bay. The main objective of this study is to investigate the effect of horizontal and vertical flow fields according to the surface and vertical observation data assimilation by upper wind conditions. Therefore, we carried out several numerical experiments with various parameterization methods for nudging coefficient considering the upper wind conditions (synoptic or asynoptic condition). Nudging considering the synoptic and asynoptic nudging coefficient does have a clear advantage over dynamic initialization, therefore appropriate limitation of these nudging coefficient values on its upper wind conditions is necessary before making an assessment. Obviously, under the weak synoptic wind, there was apparent advantage associated with nudging coefficient by the regional difference. The accuracy for the prediction of the meteorological values has been improved by applying the appropriate PBL (Planetary Boundary Layer) limitation of circulation.

The Influences of Concentration Distribution and Movement of Air Pollutants by Sea Breeze and Mist around Onsan Industrial Complex (온산공업단지 주변의 박무와 해풍발생이 대기오염물질의 이동 및 농도분포에 미치는 영향)

  • Lee, Hyung-Don;Lee, Gou-Hong;Kim, In-Deuk;Kang, Ji-Soon;Oh, Kwang-Joong
    • Clean Technology
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    • v.19 no.2
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    • pp.95-104
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    • 2013
  • Onsan Industrial Complex located in a nearby the Ulsan Petrochemical Complex and in the east of the coast. For this reason, air pollution substances emitted by Onsan Industrial Complex especially tend to have an effect on meteorological factors such as sea breeze. In this study, we assessed the frequency of sea breeze and mist using the meteorological data, and analyzed potential temperature and upper wind condition for assessment of atmospheric pollution concentration influenced by meteorological phenomena in a nearby the Onsan industrial complex. From an analysis results, when mist and sea breeze happened, each higher concentration phenomenon of $PM_{10}$ and $SO_2$ appeared each 57.2%, 71.8% and 46.6%, 57.7% respectively. Hence, we confirmed that meteorological phenomena such as mist and sea breeze had an effect on high concentration of air pollution substances in the research area. Analytical result of meteorological data in upper layer using potential temperature and wind condition, we confirmed that advection of air pollution substances emitted in Ulsan Petrochemical Complex by sea breeze have an effect on high concentration in Onsan Industrial Complex and nearby the residential area. In particular;concentration in Onsan Industrial Complex were higher than the average concentration by a factor of more than over 1.5 times when sea breeze by stable condition in atmospheric layer appeared.