Change in the Air Composition upon the Transition from the Troposphere to the Stratosphere.

Airborne sensing data are used to study the change in the air composition upon the transition from the troposphere to the stratosphere. The distribution of seven gases and the size spectrum and chemical composition of aerosol particles are analyzed. It is shown that when crossing the tropopause, the concentrations of H₂О, CO, and CH₄ sharply decrease, while the concentrations of О₃ and NO₂ and the aerosol particle number density, to the contrary, increase. Above the tropopause, Si predominates in the elemental composition and prevails in the ionic composition. In the troposphere, terrigenous elements Al, Cu, and Fe predominate, while in the ionic composition the prevailing set of several ions varies from one region to another. Noticeable differences in the size spectrum of particles are revealed as well. [ABSTRACT FROM AUTHOR]