The velocity probability density of upper atmospheric turbulence.

In a series of recent papers [Justus, 1966, 1967a, b] some of the properties of turbulence in the 90–110-km region were discussed. This note will present some preliminary findings concerning the velocity probability density function (pdf) of the turbulence in this region. The probability density p(υi) for a turbulent velocity component υi is defined so that p(υi)dvi is the probability of observing a turbulent velocity component with a value between υi and υi + dυi. The function p(υi) may be characterized by the moments μk about the average velocity υ¯i, where the μ's are given by Of particular interest are the standard deviation σ, the skewness α, and the ‘flatness’ β, which are defined by