In 2016 the authors performed space experiments to obtain the tropospheric NO2 field with the horizontal spatial resolution for the first time at the world level reaching 2.4 km. The NO2 fields were restored based on spectral measurements of GSA instrument installed on board the Russian satellites of the Resurs-P series. For the first time, the high spatial resolution of the new method makes it possible to identify local sources of NO2 pollution and their plumes. Good agreement with OMI NO2 observations with resolution 13 km x 24 km confirmed the reliability of the obtained Resurs-P NO2 fields in general. For the validation of high-detailed structures detected in the NO2 fields of GSA/Resurs-P, we are developing methods based on comparisons with chemical transport models. The comparison is performed for Hebei province, the North China Plain, which is the most NO2 polluted area in the world, using Resurs-P data obtained on September 29, 2016. The paper presents preliminary comparison of the Resurs-P tropospheric NO2 field with simulation based on HYSPLIT transport model. For the solution of the problem a high-detailed chemical transport model based on a solution of the nonlinear heat and mass transfer equation is under development. A theoretical background of the methods of asymptotic analysis of multidimensional singularly perturbed problems for the nonlinear heat and mass transfer equation is proposed.
The authors are developing methods for the determination of the emissions from urban sources of key impurities basing on surface and high-detailed satellite measurements. For the applications in these researches we develop a simplified parameterized model of chemical transformations in the atmosphere. This work is devoted to estimation of the effective lifetimes and the decay rates of nitrogen oxides (NOx) entering the atmosphere as a result of emissions of industrial enterprises basing on chemical-transport simulation. The estimation of effective decay rates, which allows to relatively simply parameterize chemical processes occurring in a plume, is necessary for further use in transport models based on systems of the diffusion-reaction-advection equations and describing the behavior of the plume. The effective decay rates are calculated as the inverse of the times over which the concentrations of the corresponding nitrogen oxides decrease by e times compared to their maximum values. The dependence of their concentrations on time is found by solving a system of kinetic equations describing the reactions occurring in the plume. For the numerical solution of the Cauchy problem, a finite-difference scheme is used that takes into account the structure of the kinetic equations and has the second order of the approximation error.