沙尘天气过程起沙特征的观测试验和参数化研究进展

Review of the field measurements and parameterization for dust emission during sand-dust events

沙尘天气过程研究中,起沙过程是沙尘传输和沉降的基础,沙尘模式中的起沙参数化方案决定了能否准确模拟和预报沙尘天气。试验观测和数值模拟是研究起沙过程的重要途径。基于风蚀起沙的物理机制,总结了起沙机制和起沙特征的研究成果,介绍了风蚀起沙的主要影响因子,回顾了起沙关键参数(临界起沙摩擦速度(u_t)或临界起沙风速(U_t)、水平跃移沙尘通量(Q)和起沙通量(F))的试验观测及其沙尘模式应用中的参数化方案,并讨论了不同起沙参数化方案的应用与校验。同时,针对目前研究中存在的问题和今后可能的研究方向提出建议。

Dust emission generated by wind erosion is a basic process before the transport and deposition of dust particles.Parameterization of dust emission flux is important for accurate simulation and prediction of dust events.Field observation and numerical simulation are two approaches to understand the complex process of dust emission.Great progress has been made on the characteristics and mechanism of dust emission during dust storm events.This review introduces the major factors influencing dust emission,and summarizes the calculation methods of several key parameters of dust emission,including the threshold friction velocity u t,threshold wind speed U_t,streamwise saltation flux Q,and（vertical） dust emission flux F,from perspectives of both observation and parameterization.The paper also discusses the improvement,application,and validation of different dust emission schemes in dust models.Existing problems and future research directions are elaborated as well.