Physico-chemical processes in the atmosphere of the earth and the methods of their diagnostics
In the recent decade, IAP has been actively developing theoretical studies and modeling of different-scale spatio-temporal variability of minor gaseous atmosphere constituents. This variability is determined primarily by the photochemical reactions that run in the atmosphere, depends significantly on the different transport processes, and is an important source of information about the current status and evolution of the atmosphere. Analysis of these processes from the viewpoint of nonlinear dynamics and development of special basic dynamic models of atmospheric photochemical systems (PCSs) serve as the basis of the studies of photochemical processes in the Earth's atmosphere supervised by A. M. Feigin. Sets of such processes and their parameters are essentially different in different atmospheric regions. Therefore, one conventionally singles out PCSs of the boundary layer, free troposphere, polar lower stratosphere, mesosphere, etc.
IAP researchers have developed a basic photochemical model of the lower-stratosphere polar PCS which demonstrates good qualitative correspondence to the observed behavior of ozone density. Instability of the Antarctic PCS has been revealed: a self-oscillatory process has been detected in an atmospheric PCS for the first time. During the period of the ozone hole formation, the corresponding PCS undergoes a series of bifurcations, and further changes in the bifurcation characteristics due to the trends in control parameters (primarily, densities of inorganic chlorine and greenhouse gases, as well as temperature) influence significantly the process of the expected ozone hole recovery (A. M. Feigin, I. B. Konovalov).
Methods of using the chemico-transport model of the lower atmosphere in combination with the data of the ground-based and satellite measurements of the atmosphere composition have been developed. These methods have been used to improve both the spatial distribution, and the temporal variability of the intensity of the sources that produce chemically active admixtures in the atmosphere. It has been demonstrated that the available satellite measurement data about the tropospheric content of nitrogen oxide can improve our knowledge about the sources of nitrogen oxide at relatively small scales that can be resolved within the typical regional chemico-transport model. Significant errors have been found in the available databases with conventional emission inventories for several countries in Southern and Eastern Europe (I. B. Konovalov).
As a result of using the developed method for calculation of emissions of chemicals and aerosols, the possibility of achieving satisfactory qualitative agreement between the measured day-to-day variations in the densities of several main atmosphere pollutants (carbon monoxide, suspended matter and ozone) and the calculated atmosphere pollution under the conditions of intense natural fires has been demonstrated for the first time (jointly with the Hydrometeorological Center of Russia).
In the process of these studies, an extensive use is made of the modern three-dimensional chemico-transport model, which was adapted for qualitative description of the evolution of the atmosphere composition over the European part of Russia. The efficiency of this model has been demonstrated for solving of a wide range of practical scientific problems related to the control over and prediction of the air quality, as well as the level of the anthropogenic load on the atmosphere.