State of the Stratospheric Aerosol Layer over Tomsk in 2017 Using Data from Sensing at Siberian Lidar Station in Tomsk

• Published in: Optical memory & neural networks Vol. 30; no. 4; pp. 267 - 275
• Main Authors: Bazhenov, O. E., Nevzorov, A. V., Dolgii, S. I., Makeev, A. P., Elnikov, A. V.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01.10.2021
• Subjects: Complexity; Computer Science; Information Storage and Retrieval; vertical distribution of stratospheric aerosol; lidar; laser sensing of the atmosphere
• ISSN: 1060-992X; 1934-7898
• DOI: 10.3103/S1060992X21040020

In this study, we present the observations of anomalous aerosol layers in summer-fall period of 2017; the observations were performed at the Siberian Lidar Station in Institute of Atmospheric Optics, Siberian Branch, Russian Academy of Sciences, at two wavelengths (355 and 532 nm). At the layer maximum, we recorded a narrow layer ~1 km in altitudinal extents on August 26, 2017 with the scattering ratios R 355 = 2.8 and R 532 = 5.8 at the altitude of 15 km. On subsequent days, the layers spanned a wider altitude interval, but were characterized by smaller scattering ratios. The availability of results from sensing these layers at two wavelengths, and accounting for the lidar ratios on the basis of model values, allowed us to estimate the Ångström exponent ( X ) both in these layers, and at the altitudes that remained undisturbed, i.e. at a background aerosol state. The minimal Ångström exponent is unity or larger in well-defined anomalous layers; while for the background aerosol, localized above 16 km, the Ångström exponent is in the interval ( X = 2.8–3.8), with a pronounced positive gradient with the growing altitude. The constructed back trajectories of air mass motion showed that the source of aerosol layers in the stratosphere over Tomsk had been forest fires in North America (Canada) in the mid-August 2017.