Seasonal features of the appearance of aerosol scattering in the stratosphere and mesosphere of Kamchatka from the results of lidar observations in 2007–2009

The behavior of the vertical aerosol structure (profiles of the ratio of the coefficients of the backward total and molecular scattering) in the height interval 30–80 km is analyzed from the results of lidar observations in Kamchatka over the period from October 2007 through December 2009. The obtained data revealed a regular two-layer aerosol structure in this height range with the maxima of the ratio of the scattering coefficients in the upper stratosphere at heights 35–50 km and in the mesosphere at heights of 60–75 km, as well as a relation between seasonal variations in the aerosol stratification and the circumpolar vortex affecting dynamic processes in the atmosphere of midlatitudes. The procedure of including the aftereffect of the Hamamatsu-M8259-01 PEM, which influences the error in the calculation of the ratio of scattering coefficients, is described.