Turbulent characteristics of saltation and uncertainty of saltation model parameters

摘要

It is widely recognised that saltation is a turbulent process, similar to other transport processes in the atmospheric boundary layer. Due to a lack of high-frequency observations, the statistic behaviour of saltation is so far not well understood. In this study, we use the data from the Japan–Australia Dust Experiment (JADE) to investigate the turbulent characteristics of saltation by analysing the probability density function, energy spectrum and intermittency of saltation fluxes. Threshold friction velocity, usub*t/sub, and saltation coefficient, csub0/sub, are two important parameters in saltation models often assumed to be deterministic. As saltation is turbulent in nature, we argue that it is more reasonable to consider them as parameters obeying certain probability distributions. We estimate these distributions using the JADE data. The factors contributing to the stochasticity of usub*t/sub and csub0/sub are examined.