Asia-Pacific Journal of Atmospheric Sciences

Korean Meteorological Society (한국기상학회)
권호 표지

Numerical Study on the Formation and Maintenance Mechanisms of Cloud Street in the East Sea during Cold Air Outbreak

Kang, Sung-Dae;Ahn, Joong-Bae

  • Published : 2008.04.10
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Abstract

The formation and maintenance mechanisms of cloud strets in the East Sea of the Korean Peninsula are studied using MM5 (ver. 3.7) with real topography, NCEP reanalysis data, and weekly OISST (Optimum Interpolation of Sea Surface Temperature). Well-organized cloud streets are simulated in to the numerical results, the formation mechanisms of cloud strets and their maintenance mechanisms are found to be different depending on their downstream distance from Baekdu Mountain. Specifically, the following seven results have been obtained. For the formation of the cloud strets at both regions: (1) both strong static instability and topographically induced mechanical disturbances are important for the formation of cloud streets near the coastal line. However, the cloud streets observed far from the coastal line can be formed only under strong static instability; (2) the strong heat fluxes (sensible and latent heat) from warm ocean surface are the main source of the formation of stratus clouds near the coastal line; (3) the buoyancy caused by the condensation process in the cloud is the main source of the convective rolls at far regions from the coastal line; (4) the positive SST forcing (which corresponds to the approaching Kuroshio Curent) enhan-ces the formation of the thin cloud streets, and negative SST-forcing generates the thick cloud streets at the far region disturbance is the main source keeping the long line-shaped cloud streets near the coastal line; (6) both vertical difusion of moisture from warm ocean surface and release of latent heat in the cloud are the main sources at the far region from the coastal line, and; (7) the radiative coling in the cloud is negligibly small at the entire region.

Keywords

References

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