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Numerical simulation of evolution of a convective cloud and precipitation during a thunderstorm event that took place on August 11, 2017 in Beijing (China) against a background of high aerosol air pollution was performed using a numerical nonstationary three-dimensional model. Different microphysical parameters of drops and ice particles which depend on aerosol pollution of the atmosphere, were varied: an autoconversion threshold for cloud droplets and raindrops and parameters of raindrop and hailstone size distribution. It was found for this case that liquid drops do not play a significant role in the convective cloud evolution. The effect of aerosol pollution both on the raindrop size spectrum and on the transition of cloud droplets to raindrops does not influence significantly dynamic, microphysical and electrical properties of the cloud. At the same time, the change in the ice particle spectrum towards the size decrease that happens under the influence of increased aerosol pollution, has a significant impact on the evolution of the cloud and precipitation. The amount of precipitation decreases both within the cloud and on the underlying surface. However, the lightning activity of the cloud changes little. [ABSTRACT FROM AUTHOR]

To quantify the responses of drivers to traffic information and the congestion evacuation effect on the basis of traffic guidance information, a multilayer network congestion risk propagation model of urban roads was built to analyse the influence of the advanced traveller information system (ATIS) penetration rate, group behaviours of drivers, and traveller flow distribution features on the traffic congestion risk propagation of urban roads. Meanwhile, the dynamic evolutionary characteristics of group behaviours of drivers in a road network under the guidance of traffic information were analysed with the microscopic Markov chain approach (MMCA). A simulation analysis of the artery network in the fourth ring of Beijing was also carried out. Results demonstrated that the influence of traffic information and drivers' information reinforcement psychology on congestion risk propagation depend on the aggregation effect caused by traffic information. Increasing the ATIS market penetration rate and drivers' acceptance of information is beneficial to relieve traffic congestion as long as the drivers' aggregation effect is within a critical range. [ABSTRACT FROM AUTHOR]