DOI QR코드

DOI QR Code

2020 강원영동 공동 입체기상관측 기간 강풍 사례에 대한 관측자료와 수치모델 비교 분석

Comparative Analysis of Observation and NWP Data of Downslope Windstorm Cases during 3-Dimensional Meteorological Observation Project in Yeongdong Region of Gangwon province, South Korea in 2020

  • 권순범 (강원지방기상청 예보과) ;
  • 박세택 (강원지방기상청 예보과)
  • 투고 : 2021.05.20
  • 심사 : 2021.07.26
  • 발행 : 2021.11.30

초록

In order to investigate downslope windstorm by using more detailed observation, we observed 6 cases at 3 sites - Inje, Yongpyeong, and Bukgangneung - during "3-D Meteorological Observation Project in Yeongdong region of Gangwon province, South Korea in 2020." The results from analysis of the project data were as follows. First, AWS data showed that a subsidence inversion layer appeared in 800~700 hPa on the windward side and 900~850 hPa on the leeward side. Second, before strong wind occurred, the inversion layer had descended to about 880~800 hPa. Third, with mountain wave breaking, downslope wind was intensified at the height of 2~3 km above sea level. After the downslope wind began to descend, the subsidence inversion layer developed. When the subsidence inversion layer got close to the ground, wind peak occurred. In general, UM (Unified Model) GDAPS (Global Data Assimilation Prediction System) have had negative bias in wind speed around peak area of Taebaek mountain range, and positive bias in that of East Sea coast area. The stronger wind blew, the larger the gap between observed and predicted wind speed by GDAPS became. GDAPS predicted strong p-velocity at 0600 LST 25 Apr 2020 (4th case) and weak p-velocity at 2100 LST 01 Jun 2020 (6th case) on the lee-side of Taebaek mountain range near Yangyang. As hydraulic jump theory was proved, which is known as a mechanism of downslope windstorm in Yeongdong region, it was confirmed that there is a relationship between p-velocity of lee-side and wind speed of eastern slope of Taebaek mountain range.

키워드

참고문헌

  1. Barcilon, A., J. C. Jusem, and P. G. Drazin, 1979: On the two-dimensional, hydrostatic flow of a stream of moist air over a mountain ridge. Geophys. Astro. Fluid Dyn., 13, 125-140. https://doi.org/10.1080/03091927908243765
  2. Brinkmann, W. A. R., 1974: Strong downslope winds at Boulder, Colorado. Mon. Wea. Rev., 102, 592-602. https://doi.org/10.1175/1520-0493(1974)102<0592:SDWABC>2.0.CO;2
  3. Cho, Y.-J., T.-Y. Kwon, and B.-C. Choi, 2015: Characteristics of meteorological variables in the leeward side associated with the downslope windstorm over the Yeongdong region. J. Korean Earth Sci. Soc., 36, 315-329, doi:10.5467/JKESS.2015.36.4.315 (in Korean with English abstract).
  4. Clark, T. L., and W. R. Peltier, 1984: Critical level reflection and the resonant growth of nonlinear mountain waves. J. Atmos. Sci., 41, 3122-3134. https://doi.org/10.1175/1520-0469(1984)041<3122:CLRATR>2.0.CO;2
  5. Colson, D., 1954: Meteorological problems in forecasting mountain waves. Bull. Amer. Meteor. Soc., 35, 363-371. https://doi.org/10.1175/1520-0477-35.8.363
  6. Durran, D. R., 1990: Mountain Waves and Downslope Winds. In W. Blumen et al. Eds., Atmospheric Processes over Complex Terrain. Meteorological Monographs, vol. 23, Amer. Meteor. Soc., 59-81, doi:10.1007/978-1-935704-25-6_4.
  7. Durran, D. R., and J. B. Klemp, 1983: A compressible model for the simulation of moist mountain waves. Mon. Wea. Rev., 111, 2341-2361. https://doi.org/10.1175/1520-0493(1983)111<2341:ACMFTS>2.0.CO;2
  8. Houghton, D. D., and A. Kasahara, 1968: Nonlinear shallow fluid flow over an isolated ridge. Commun. Pur. Appl. Math., 21, 1-23. https://doi.org/10.1002/cpa.3160210103
  9. Jang, W., and H.-Y. Chun, 2008: Severe downslope windstorms of Gangneung in the springtime. Atmosphere, 18, 207-224 (in Korean with English abstract).
  10. Klemp, J. B., and D. K. Lilly, 1975: The dynamic of wave-induced downslope winds. J. Atmos. Sci., 32, 320-339. https://doi.org/10.1175/1520-0469(1975)032<0320:TDOWID>2.0.CO;2
  11. Lee, J. G., and S.-R. In, 2009: A numerical sensitivity experiment of the downslope windstorm over the Yeongdong region in relation to the inversion layer of temperature. Atmosphere, 19, 331-344 (in Korean with English abstract).
  12. Lilly, D. K., and J. B. Klemp, 1979: The effects of terrain shape on nonlinear hydrostatic mountain waves. J. Fluid Mech., 95, 241- 261. https://doi.org/10.1017/S0022112079001452
  13. Long, R. R., 1953: Some aspects of the flow of stratified fluids: I. A theoretical investigation. Tellus, 5, 42-58. https://doi.org/10.1111/j.2153-3490.1953.tb01035.x
  14. Miller, P. P., and D. R. Durran, 1991: On the sensitivity of downslope windstorms to the asymmetry of the mountain profile. J. Atmos. Sci., 48, 1457-1473. https://doi.org/10.1175/1520-0469(1991)048<1457:OTSODW>2.0.CO;2
  15. Queney, P., G. A. Corby, N. Gerbier, H. Koschmieder, and J. Zierep, 1960: The airflow over mountains. WMO Tech. Note 34, World Meteorological Organization, 135 pp.