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경사가 있는 지형의 거칠기 아층에서 풍향시어와 운동량 플럭스의 특성

이영희
Lee, Young-Hee

  • 투고 : 2015.03.13
  • 심사 : 2015.10.05
  • 발행 : 2015.12.31

초록

We have analyzed wind and eddy covariance data collected within roughness sublayer over sloping terrain. The study site is located on non-flat terrain with slopes in both south-north and east-west directions. The surface elevation change is smaller than the height of roughness element such as building and tree. This study examines the directional wind shear for data collected at three levels in the lowest 10 m in the roughness sublayer. The wind direction shear is caused by drag of roughness element and terrain-induced motions at this site. Small directional shear occurs when wind speed at 10 m is strong and wind direction at 10 m is southerly which is the same direction as upslope flow near surface at this site during daytime. Correlation between vertical shear of lateral momentum and lateral momentum flux is smaller over steeply sloped surface compared to mildly sloped surface and lateral momentum flux is not down-gradient over steeply sloped surface. Quadrant analysis shows that the relative contribution of four quadrants to momentum flux depends on both surface slope and wind direction shear.

키워드

Eddy covariance data;lateral momentum flux;non-flat terrain;wind direction shear

참고문헌

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피인용 문헌

  1. Uncertainty Analysis of the Eddy-Covariance Turbulent Fluxes Measured over a Heterogeneous Urban Area: A Coordinate Tilt Impact vol.26, pp.3, 2016, https://doi.org/10.14191/Atmos.2015.25.4.591

과제정보

연구 과제 주관 기관 : 경북대학교