Application and Verification of Clear-Air Turbulence (CAT) Forecast Indices in Korea

^*Young-Gon Lee, ^*Byoung-Cheol Choi, ^**Robert Sharman, and ^**Gerry Wiener

^*Applied Meteorological Research Laboratory, Meteorological Research Institute, Seoul, Korea

^**National Center for Atmospheric Research, Boulder CO, 80307, USA

ABSTRACT

Five indices suggested by prior researchers for the diagnosis of aviation scale turbulence, such as CAT (clear air turbulence), were calculated from the RDAPS (Regional Data Assimilation and Prediction System) output produced by KMA.  The effectiveness of the indices was verified by available pireps  for two cases during the growth and passage of the low pressure system over Korea at the beginning of October 2001.  All indices except for Richardson number (Ri) predicted roughly similar distributions of the turbulence potential.  The results computed from the data prior to 12 hours generally showed larger values and more enhanced fields than those from the later data.  Though there are many problems in resolving and predicting aircraft scale turbulence, this study is encouraging, and could be of help in the prevention and reduction of the aviation accidents caused by turbulence.

Key Words : Aviational turbulence, CAT, turbulence potential

Corresponding author

    Young-GonLee, Applied Meteorology Laboratory, Meteorological Research Institute,

460-18, Shindaebang-dong, Dongjak-gu, Seoul, 156-720, KOREA

Phone: +82-2-842-0940(ext. 886) / +82-2-846-2850

    Fax: +82-2-846-2851                                   E-mail : yglee@metri.re.kr