Application of Atmospheric Turbulence Estimated Using the Thorpe Analysis Method and Operational Radiosonde Data in the United States to Aviation Turbulence

In this study, we estimated atmospheric turbulence in the free atmosphere in terms of an eddy dissipation rate (ε) using Thorpe analysis and U.S. high vertical-resolution radiosonde data (HVRRD) over 77 months (January 2012 to May 2018) at 68 operational stations. These HVRRD have a vertical resolution of about 5 m and extend to an altitude of approximately 33 km, and thus turbulence can be retrieved in the entire troposphere and lower stratosphere. The one third power of the eddy dissipation rate (EDR=ε^1/3), which is the primary matrix of aviation turbulence, showed that it is the highest in the midwestern and southeastern U.S. mainland at 20-45 kft. The number of light-or-greater (LOG) intensity EDR is decreased with increasing altitude, and the largest in summer and smallest in winter. The EDR calculated using HVRRD (HVRRD-EDR) is compared with in-situ flight EDR which is produced by commercial airlines. HVRRD-EDR and in-situ flight EDR are generally consistent with each other, in its probability density functions, vertical, and monthly distributions, although the horizontal distribution is somewhat different. The results confirm that HVRRD-EDR can be utilized as additional data in aviation turbulence studies, which can produce easily from daily operational radiosonde data of 1-s resolution. The spatial and temporal variations of HVRRD-EDR and in-situ flight EDR and their comparisons will be presented in the conference.