Deriving the slant visibility using the Klett method and the visualization of the slant visibility at the airport

摘要

Atmosphere visibility is one of the most important meteorological quantities in civil aviation domain. In practice the slant visibility is more important than the horizontal visibility for the pilot. With the help of the known Klett approach, a lidar can be used for determination of atmosphere extinction coefficient profiles. Consequently, the slant visibility can be obtained. However, the boundary value of the atmosphere extinction coefficient and the k factor in the relationship between atmosphere extinction coefficient and the atmosphere backscattering coefficient have to be firstly determined. In the present work we construct the nonlinear equations that the atmosphere extinction coefficient and the k factor must satisfy. As the solutions of the equations the atmosphere extinction coefficient and the k factor are for the first time obtained simultaneously. At the end the atmosphere extinction coefficients and the slant visibilities are obtained. The numerical simulations have been performed using the real lidar data and the aerosol optical depth observed by the installed sun photometer. The flights are demonstrated using the popular flight simulator Prepar3D under different visibilities.