Abstract:In order to study the influence of two kinds of cloud seeding agents, glaciogenic agents and hygroscopic agents, which are widely used in weather modification, on microphysical characteristics of aerosol particles produced by combustion in natural atmosphere, an experimental study on the combustion of seeding agents for cold and warm clouds seeding in clear sky was carried out based on a weather modification aircraft equipped with aerosol and cloud condensation nuclei (CCN) observation equipments. The results showed that the airborne detection equipments could not get the microphysical changes of aerosol particles and CCN before and after the combustion of glaciogenic agent (AgI) due to the limited observation scale of the aerosol equipment (PCASP). While, after the combustion of hygroscopic agents, it was found that the aerosol and CCN particle number concentrations increased significantly, reaching 1772.4 cm-3 and 1809.01cm-3 respectively, which were more than 4 times of those values before the hygroscopic agents combustion. Most of the aerosol particles size was below 0.5 μm, and the peak value of particle spectrum was 4.8 times of that before combustion, and it had the significant characteristics of forming CCN. Based on the observation results, the nucleation rate after flame catalytic combustion and the new catalytic ways are discussed. The method of this aircraft experiment provides scientific reference for further study of the physical and chemical characteristics of the particles generated by combustion of cloud seeding agents. Furthermore, the research results can provide objective initial field data support for the establishment of cloud catalytic models, especially warm cloud catalytic models.