Atmosphere (대기)

Korean Meteorological Society (한국기상학회)
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Vertical Vorticity Structure Associated with the Boreal Summer Intraseasonal Oscillation: Barotropic or Baroclinic?

여름철 계절내 진동에 의한 대기 와도의 연직 구조: 순압성 또는 경압성?

  • Song, Eun-Ji (Division of Earth Environmental System, Department of Atmospheric Sciences, Pusan National University) ;
  • Seo, Kyong-Hwan (Division of Earth Environmental System, Department of Atmospheric Sciences, Pusan National University)
  • 송은지 (부산대학교 지구환경시스템학부 대기환경과학과) ;
  • 서경환 (부산대학교 지구환경시스템학부 대기환경과학과)
  • Received : 2012.05.31
  • Accepted : 2012.06.28
  • Published : 2012.06.30
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Abstract

This study investigates the reason why the barotropic vorticity structure prevails vertically in response to the enhanced convection associated with the boreal summer intraseasonal oscillation over the central Indian Ocean. The relative vorticity tendency analysis for a 2.5-layer simplified model demonstrates that the barotopic vorticity structure is predominant due to the following two factors: 1) vertical easterly shear on the meridional gradient of barotropic divergence (which induces generation of barotropic vorticity twice larger than that of baroclinic vorticity); and 2) vertical easterly shear on the meridional gradient of baroclinic divergence (which appears only in relation to the generation of barotropic vorticity). The percentage of contribution by each term to barotropic and baroclinic vorticity tendency equations is presented.

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References

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