Characteristics of Energy Dissipation Rate at the Standard Weather Observatory Under Various Atmospheric Conditions and Its Application to Aviation Turbulence Intensity

Abstract

Accurate prediction of low-level turbulence (LLT) is critical for aviation safety, particularly for the emerging urban air mobility industry and aircraft takeoffs and landings. To better understand and predict these hazards, the characteristics of the energy dissipation rate (EDR) in the atmospheric boundary layer (ABL) were investigated using 8-year high-frequency sonic anemometer observations collected at multiple altitudes of the 307-m meteorological tower in the Boseong Standard Weather Observatory (BSWO), South Korea. EDR was estimated using the inertial dissipation technique with second-order structure functions after applying quality control procedures to the sonic anemometer data. The probability density functions (PDFs) of EDR, representing the characteristics of EDR, exhibited lognormal distributions, although a transition toward log-Weibull-like distributions was observed near the surface and under unstable conditions. The PDFs of EDR had distinct characteristics on days dominated by sea breezes at the BSWO, showing lower EDR values and lognormal-like distributions compared to non-sea breeze days. This was attributed to weaker large-scale forcings, wind shear, and turbulence kinetic energy, which may cascade down to the inertial subrange, resulting in lower EDR. The anisotropic nature of turbulence in the ABL was observed from the relationship between EDR estimates of different velocity components, with streamwise EDR estimates being larger than vertical estimates. The ensemble mean of EDR obtained from best-fit lognormal distributions to the observed PDFs of EDR was in the reasonable ranges presented in previous studies, yet showing different magnitudes. These findings provide essential statistical parameters for developing LLT forecasting systems optimized for the Korean Peninsula.