Clear Air Turbulence Resolved by Numerical Weather Prediction Model Validated by Onboard and Virtual Flight Data

Abstract

Abstract A clear air turbulence (CAT) occurred on 30 December 2020 over Tokyo, Japan. The CAT was largely generated by breaking Kelvin‐Helmholtz (KH) instability waves in the free atmosphere. A regional numerical weather prediction model simulated the event with fine resolution (35 m). Onboard‐recorded flight data and a flight simulation were utilized to validate the meteorological simulation. The locations of the reproduced strong turbulence agree well with the regions where flights encountered turbulence on that day. In a simulation with the finest resolution, the KH waves and their breaking were resolved. When the resolution was finer, the turbulent eddies were stronger, causing meteorological effects on the airplanes. The response of a virtual airplane to the simulated turbulence was estimated using a flight simulation. By comparing onboard‐recorded data with virtual flight data, we confirm that turbulent eddies are reasonably reproduced.

Keywords

• atmospheric turbulence
• clear air turbulence
• large eddy simulation
• Kelvin‐Helmholtz instability
• flight simulation
• flight record