Представлены результаты лидарных измерений вертикального распределения озона в нижней стратосфере-верхней тропосфере на Сибирской лидарной станции Института оптики атмосферы им. В.Е. Зуева над Томском. Описан годовой ход вертикального распределения озона и зарегистрированный в марте 2023 года довольно редкий процесс стратосферно-тропосферного переноса воздушных масс через тропопаузу. This paper presents the results of lidar measurements of vertical ozone distribution in the lower stratosphere-upper troposphere at the Siberian lidar station of the Atmospheric Optics Institute of V.E. Zuev over Tomsk. The annual variation of vertical ozone distribution is described, along with a rather rare event of stratosphere-troposphere mass transport registered in March 2023.

The report presents and summarizes the results of lidar measurements of the vertical distribution of the stratospheric aerosol layer (CA) and ozone, made at the Siberian Lidar Station (SLS). Based on a long series of observations of the integral coefficient of reverse aerosol scattering, an analysis of changes in the stratospheric aerosol layer was carried out in Tomsk in 2018–2024. The annual course of the vertical distribution of ozone is described and a rather rare process of stratospheric-tropospheric transport of air masses through the tropopause was registered in March 2023.

На основе длинного ряда наблюдений интегрального коэффициента обратного аэрозольного рассеяния, полученного на Сибирской лидарной станции ИОА СО РАН в Томске за 2018-2024 гг. проведен анализ изменений стратосферного аэрозольного слоя. Построены тренды изменений этого параметра атмосферы, они показывают замедление наполнения стратосферного аэрозоля. Средние по сезонам вертикальные профили отношения рассеяния за 2023-2024 гг. показывают уменьшение значений за период зима-весна и выше 20 км летом-осенью по сравнению с профилями 2018-2023 гг. В то время как, средние профили периода лето-осень на высотах от тропопаузы до 20 км показывают рост по сравнению с профилями 2018-2023 гг. Based on a long series of observations of the integral coefficient of reverse aerosol scattering obtained at the Siberian Lidar Station of the IOA SB RAS in Tomsk for 2018-2024, an analysis of changes in the stratospheric aerosol layer was carried out. Trends of changes in this parameter of the atmosphere are plotted, they show a slowdown in the filling of the stratospheric aerosol. The seasonal average vertical profiles of the scattering ratio for 2023-2024 show a decrease in values over the winter-spring period and above 20 km in summer-autumn compared with the profiles of 2018-2023. At the same time, the average profiles of the summer-autumn period at altitudes from the tropopause to 20 km show an increase compared to the profiles of 2018-2023.

С 2021 года начата работа с данными спутника Suomi. В докладе представлен пример сопоставлений лидарных и спутниковых измерений вертикального распределения концентрации озона в верхней тропосфере – стратосфере, полученный с помощью лидарного комплекса дифференциального поглощения и спутников Aura, MetOp, Suomi. Восстановление вертикального распределения озона выполнялось с использованием вертикального распределения температуры по данным метеорологического спутника MetOp. Выявлены пространственно-временные расхождения между измерениями Сибирской лидарной станции (СЛС) и спутником Suomi.

В докладе приводятся и обобщаются результаты лидарных измерений на Сибирской лидарной станции (СЛС) вертикального распределения стратосферного аэрозольного слоя (СА) в 2021г. Приводится описание и техника измерений многоканального стационарного лидарного комплекса Института оптики атмосферы СО РАН в Томске. Исходя из результатов измерений и анализа полученных данных подтверждается закономерность в увеличении накопления фонового аэрозоля в период осень – зима с его последующим активным истощением в летний период.

На Сибирской лидарной станции Института оптики атмосферы им. В.Е. Зуева СО РАН в Томске (56.5 с.ш., 85.0 в.д.) для исследования динамики озона в районе тропопаузы и изучения стратосферно-тропосферного обмена работает лидар для измерения вертикального распределения озона в верхней тропосфере-нижней стратосфере. В работе приводятся результаты сравнения применяемых на данном лидаре для регистрации сигналов ФЭУ R7207-01 совместно с усилителями-дискриминаторами C3866 фирмы HAMAMATSU и модулями ФЭУ H12386-210 на парах длин волн 299/341 нм. Показана перспективность использования новых фотоприемных модулей ФЭУ H12386-210 для зондирования озона на паре длин волн 299/341 нм.

In the report we analyze the data from lidar measurements of aerosol optical characteristics over Tomsk. Based on time series of long-term measurements of integrated aerosol backscattering coefficient 𝐵π 𝑎 (see PDF) , for the background state of the stratosphere we constructed the linear regressions for the period of 1986 – 1991 with stratospheric aerosol (SA) content decreasing at a rate of −5.1 ∙ 10−7sr-1 per decade; for the period of 2000 - 2006 with SA decreasing at a rate of −6.31 ∙ 10−8 sr-1 per decade; for the period of 2012 – 2017 with SA decreasing at a rate of −1.79 ∙ 10−8 sr-1 per decade; as well as for the period of 2018 - 2021. After products from 2017 forest fires in North America were observed at SLS in Tomsk, since 2018 SA has started growing at a rate of 4.8 ∙ 10−7sr-1 per decade. We corrected the regional empirical model of background stratospheric aerosol, which we developed in 2000-2017, by complementing it with measurements from 2017 to 2021.

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.

Lidar observations of aerosol and ozone at Siberian Lidar Station (SLS) of Institute of Atmospheric Optics, Siberian Branch, Russian Academy of Sciences in Tomsk (26° 29’ N; 85° 3’ E) showed the presence of stratospheric aerosol layers over Tomsk during winter 2017-2018, signs of descending air masses, and deficit of ozone. Aura OMI/MLS observations indicated that in December-January 2017/2018 the northern Eurasia had been under the influence of Arctic air masses from the Eastern Hemisphere with low total ozone (TO) content and NO2 content in the stratosphere, and low temperature in the stratosphere. Analysis of back trajectories and integrated (over MLS profile) TO showed that, due to dynamic disturbance of the Arctic stratosphere in December 2017, cold air masses with excessive reactive chlorine (in view of NO2 deficit) were exported from within the Arctic circle to the stratosphere over Tomsk. Seemingly, in the Tomsk stratosphere, after being exposed to solar radiation and to the excessive reactive chlorine (in view of NO2 deficit), and, staying chemically isolated, they evolved into chemically disturbed state, similar in ozone destruction rate to the conditions of the springtime Arctic stratosphere.

Lidar observations of aerosol and ozone, carried out at Siberian Lidar Station (SLS) of Institute of Atmospheric Optics, Siberian Branch, Russian Academy of Sciences in Tomsk (56°29′ N; 85°3′ E), showed the presence of stratospheric aerosol layers over Tomsk during winter 2017–2018, signs of descending air masses, and deficit of ozone. The Aura OMI/MLS observations indicated that in December-January 2017/2018 the northern Eurasia had been under the impact of Arctic air masses from the Eastern Hemisphere with deficient total ozone (TO) and NO 2 contents in the stratosphere, and low temperature in the stratosphere. Analysis of back trajectories and MLS profile-integrated TO showed that due to dynamic disturbance of the Arctic stratosphere in December 2017, cold air masses with excessive reactive chlorine (in view of deficient NO 2 ) were exported from within the Arctic circle to the stratosphere over Tomsk. Seemingly, in the Tomsk stratosphere, after being exposed to solar radiation and to the excessive reactive chlorine (in view of NO 2 deficit), and, staying chemically isolated, they evolved into chemically disturbed state, similar in ozone destruction rate to the conditions of the springtime Arctic stratosphere. The correlations between deviations in water vapor and ozone mixing ratios and number concentrations are most strong for mixing ratios, for Eureka, Ny-Ålesund, Jokioinen, St. Petersburg, and Tomsk, and for December 2017 (versus January 2018).

In the report we present a quasi-three-year seasonal model of ozone vertical profiles; the model is obtained using the differential absorption lidar complex at Siberian Lidar Station (SLS) and Aura and MetOp satellites in the upper troposphere – stratosphere. Ozone profiles were retrieved using temperature vertical distribution from meteorological satellites. We analyzed and estimated the effect of different spatial resolutions on the error of ozone profiles retrieved using lidar and satellite measurements in 2021.

At the Siberian lidar station, long-term measurements of the ozone vertical distribution are continued at the sensing wavelength pairs of 299 and 341 nm, 308 and 353 nm. The report presents a quasi-three-year seasonal model of vertical ozone profiles formed in recent years, obtained using the differential absorption lidar complex of the Siberian lidar station and the Aura, MetOp satellites in the upper troposphere - stratosphere. A typical seasonal feature of the vertical ozone distribution in Western Siberia is presented. The ozone profiles were retrieved using the vertical temperature distribution from the meteorological satellite data. We analyzed how the existing sets of absorption cross sections influence the deviation of the ozone profiles, retrieved with their application, from the Krueger model and the quasi-three-year model. Since 2021, measurements have been performed at the lidar station with different spatial resolutions from 10 m to 100 m. An analysis and estimation of how different spatial resolutions influence the error of retrieving ozone profile from lidar and satellite measurements in 2021 was conducted.

STRACT In the report we show the lidar measurement complex of Siberian Lidar Station, having formed to date. The main units of the measurement complex are technically described, and instrumentation and certain measurements of stratospheric aerosol, ozone, and temperature of the middle atmosphere are presented.

In this report we compare seasonal vertical profiles of ozone, obtained at differential absorption lidar complex of Siberian Lidar Station (SLS) in the upper troposphere - stratosphere, using measurements of vertical temperature distribution onboard meteorological satellites Aura, MetOp and model developed in Institute of Atmospheric Optics. We analyzed and estimated how the real temperature influences the behavior of ozone profiles retrieved from lidar measurements in 2018 and 2019.

The paper presents the results of DIAL measurements of the vertical ozone distribution at the Siberian lidar station. Sensing is performed according to the method of differential absorption and scattering at wavelength pair of 299/341 nm, which are, respectively, the first and second Stokes components of SRS conversion of 4th harmonic of Nd: YAG laser ( 266 nm) in hydrogen. Lidar with receiving mirror 0.5 m in diameter is used to implement sensing of vertical ozone distribution in altitude range of 6-16 km. The temperature correction of zone absorption coefficients is introduced in the software to reduce the retrieval errors.

In the report we compare the vertical ozone profiles, measured using lidar complex of differential absorption at Siberian Lidar Station (SLS), against profiles, obtained using data from AURA meteorological satellite. Lidar and satellite measurements of ozone in the lower troposphere-stratosphere over Tomsk are analyzed, as well as data from meteorological stations closest to the city. The results obtained are an indirect confirmation of stratosphere-troposphere exchange (STE) of air masses.

In the report, we present certain results of studying the vertical distribution of stratospheric aerosol layer (SAL), obtained at the Siberian Lidar Station, Tomsk in December 2017 – January 2018. A block-diagram of lidar is presented. It is shown the aerosol loading of the stratosphere might be due to the occurrence of polar stratospheric clouds (PSC) as a result of transport of Arctic air masses to Tomsk.

In the report, we present and summarize the results of lidar measurements of stratospheric aerosol layer at the Siberian Lidar Station (Tomsk: 56.5 degrees N; 85.0 degrees E) in 2017. Measurement technique with the help of multichannel stationary lidar complex at Institute of Atmospheric Optics, Siberian Branch, Russian Academy of Sciences, Tomsk, is described. The measurements showed that in August - October there were aerosol layers in the altitude range from 14 to 19 km, with R(H) value at maximum having been from 1.3 to 5.8. The trajectory analysis of air mass transport in the atmosphere on the basis of the NOAA HYSPLIT models allowed us to determine that the observed aerosol layers could possibly be due to atmospheric transport of forest fire products from the region of lake Athabasca (Saskatchewan and Alberta provinces, Canada) to the atmosphere.

A lidar complex designed at V.E. Zuev Institute of Atmospheric Optics, Siberian Branch, Russian Academy of Sciences (Tomsk) and used at the Siberian Lidar Station (56.5° N, 85.0° W) for the study of ozone dynamics near tropopause and for tracking global ozonosphere changes is presented. It allows measurements of ozone vertical distribution in the upper troposphere–stratosphere when sounding using the differential absorption technique at the wavelength pairs 299/341 and 308/353 nm. The lidar complex covers altitudes from ∼5 to ∼45 km.