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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 NO2 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 NO2) 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. The correlations between deviations in water vapor and ozone mixing ratios and number concentrations are most strong for mixing ratios, for Eureka, Ny-Alesund, Jokioinen, St. Petersburg, and Tomsk, and for December 2017 (versus January 2018).

Lidar observations at Siberian Lidar Station (SLS) of the Institute of Atmospheric Optics, Siberian Branch, Russian Academy of Sciences, in Tomsk (56.5° N; 85.0° E) showed the presence of stratospheric aerosol layers, descent of air masses, and deficit of ozone over the city during winter 2017–2018. Aura OMI/MLS data indicated that the total ozone (TO) content and NO2 content in the stratosphere over northern Eurasia, as well as the temperature in the stratosphere, were significantly lower than normal in December 2017–January 2018. Analysis of back trajectories and integrated (over profile) TO showed that the dynamic disturbance of the Arctic stratosphere in December 2017 led to the extrusion of cold air masses with excessive reactive chlorine content (in view of NO2 deficit) beyond the Arctic circle and their intrusion into the stratosphere of Tomsk. Seemingly, they were exposed to solar radiation in the stratosphere over Tomsk and, staying spatially isolated, became chemically disturbed. This state is similar to the state of the springtime Arctic stratosphere, where ozone is intensely destroyed until the final warming.

Laser ranging methods employing light detection and ranging (LiDAR) technology are widely used for studying the atmosphere and monitoring its state. The purpose of this work is to measure the ozone...

Lidar and searchlight instruments and techniques for atmospheric research developed at the V.E. Zuev Institute of Atmospheric Optics, Siberian Branch, Russian Academy of Sciences, in recent years are described. Key results obtained using these techniques are presented.

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.

The purpose of the work is to study the influence of temperature correction on ozone vertical distribution (OVD) in the upper troposphere&ndash, stratosphere in the altitude range~(5&ndash, 45) km, using differential absorption lidar (DIAL), operating at the sensing wavelengths 299/341 nm and 308/353 nm. We analyze the results of lidar measurements, obtained using meteorological data from MLS/Aura and IASI/MetOp satellites and temperature model, at the wavelengths of 299/341 nm and 308/353 nm in 2018 at Siberian Lidar Station (SLS) of Institute of Atmospheric Optics, Siberian Branch, Russian Academy of Sciences. To estimate how the temperature correction of absorption cross-sections influences the OVD retrieval from lidar measurements, we calculated the deviations of the difference between two profiles, retrieved using satellite- and model-based temperatures. Two temperature seasons were singled out to analyze how real temperature influences the retrieved OVD profiles. In the stratosphere, when satellite-derived temperature and model are used for retrieval, the deviations may reach absolute values of ozone concentration in the range from &minus, 0.97 &times, 1012 molecules &times, cm&ndash, 3 at 19.7 km to 1.05 &times, 3 at 25.3 km during winter&ndash, spring season, and from &minus, 0.17 &times, 3 at height of 17.4 km to 0.27 &times, 3 at 40 km in summer&ndash, fall period. In the troposphere, when satellite-derived temperature is used in the retrieval, the deviations may reach absolute values of ozone concentration in the range from &minus, 1.95 &times, 3 at 18.6 km to 1.23 &times, 3 at 18.2 km during winter&ndash, 0.15 &times, 3 at height of 11.4 km to 0.3 &times, 3 at 8 km during summer&ndash, fall season.

A lidar system has been built at the Siberian Lidar Station of the V. E. Zuev Institute of Atmospheric Optics of the Siberian Branch of the Russian Academy of Sciences in Tomsk (56.5 N, 85.0 E) to study the dynamics of ozone in the region of the tropopause and monitor global changes in the ozonosphere by measuring the vertical distribution of ozone in the upper troposphere–stratosphere. Probing is by differential absorption using the wavelength pairs 299/341 and 308/353 nm with temperature and aerosol corrections taken into account. The lidar system covers an altitude range of ~5–45 km.

The purpose of this work is to measure the ozone vertical distribution (OVD) in the upper troposphere&ndash, stratosphere by differential absorption lidar (DIAL) at 299/341 nm and 308/353 nm and to compare and analyze the results against satellite data. А lidar complex for measuring the OVD in the altitude range &asymp, (5&ndash, 45) km has been created. Here we analyze the results of ozone lidar measurements at wavelengths of 299/341 nm and 308/353 nm in 2018 at Siberian Lidar Station (SLS) and compare them with satellite (MLS/Aura and IASI/MetOp) measurements of OVD. The retrieved lidar OVD profiles in the upper troposphere&ndash, stratosphere in comparison with MLS/Aura and IASI/MetOp profiles, as well as the stitched OVD profile in comparison with the mid-latitude Krueger model, confirm the prospects of using the pairs of ozone sounding wavelengths 299/341 and 308/353 nm.

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.

We present the annual variations in the total ozone (TO) content over Tomsk in the period of 1994-2017, obtained using М-124 ozonometer, and in the integrated aerosol backscattering coefficient in the period of 2000-2016. Their analysis made it possible to formulate the notion of seasonal behavior of these constituents and to compare their variations with the processes in “charging”/“discharging” capacitor.

The purpose of this work is to measure by differential absorption lidar (DIAL) the ozone vertical distribution (OVD) in the upper troposphere – stratosphere at wavelengths 299/341 and 308/353 nm and to compare the results with satellite data. А lidar complex for measuring the OVD in the altitude range ~ (5–45) km has been created. Here we analyze the results of ozone lidar measurements at wavelengths of 299/341 nm and 308/353 nm in March 2017 – January 2018 at Siberian Lidar Station (SLS) and compare them with satellite (AURA/MLS and IASI/MetOp) measurements of OVD. The retrieved lidar OVD profiles in the upper troposphere – stratosphere in comparison with AURA/MLS and IASI/MetOp profiles, as well as the stitched OVD profile in comparison with the mid-latitude Kruger model confirm the prospects of using the pairs of ozone sounding wavelengths 299/341 and 308/353 nm.

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.

Ozone was sensed with lidar at wavelength pairs 299/341 and 308/353 nm, allowing the vertical ozone stratification to be monitored within the upper troposphere – lower stratosphere, and within the stratosphere. The ozone lidar sensing, performed according to the method of differential absorption and scattering, is compared with data of IASI/MetOp and AURA satellites, as well as with the midlatitude Krueger model.

In the report, we present and summarize the results of lidar measurements of stratospheric aerosol layer at the Siberian Lidar Station (Tomsk: 56.5°N; 85.0°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 for DIAL measuring the vertical distribution of ozone at the wavelengths 299/341 nm and 308/353 nm is presented. The wavelengths used allow monitoring of vertical stratification of ozone within the upper troposphere - stratosphere. The results of lidar ozone sensing are given in comparison with the IASI/MetOp and MLS/AURA satellites. The results of comparison of the reconstructed profiles of the vertical distribution of ozone with allowance for temperature and aerosol correction confirm the prospects of using the complex of the ozone probing wavelengths of 299/341 nm and 308/353 nm. The results of the comparison show a high accuracy of ozone concentration measurements in the altitude range of 5 to 45 km.

The technique of lidar sensing of the atmosphere by the differential absorption method is described for retrieval of the vertical ozone profiles corrected for the effect of the temperature and aerosol. Wavelengths perspective for measuring the ozone profiles in the upper troposphere and the lower stratosphere are determined. Results of lidar measurements at selected wavelengths of 299 and 341 nm are in agreement with model estimates. This indicates the acceptable accuracy of ozone sensing at altitudes 6–18 km.

We present an algorithm for retrieval of vertical distribution of ozone with temperature and aerosol correction during DIAL lidar sounding of the atmosphere. Most suitable wavelengths for measurements of ozone profiles in the upper troposphere--lower stratosphere are selected. Results of lidar measurement at wavelengths of 299 and 341 nm agree with model estimates, which point to acceptable accuracy of ozone sounding in the 6---18 km altitude range.

We consider the results of long-term remote optical monitoring obtained at the Siberian Lidar Station of Institute of Atmospheric Optics, Siberian Branch, Russian Academy of Sciences, Tomsk 56° 30′ N, 85° E. The scattering characteristics of stratospheric aerosol layer, obtained according to data of lidar measurements recorded since 1986, are presented. We analyse the trends of changes in the total ozone TO content over Tomsk for the period 1996–2013 according to data of spectrophotometric measurements employing Total Ozone Mapping Spectrometer TOMS data for the period 1979–1994. We determined the periods of elevated content of stratospheric aerosol over Tomsk after a series of explosive eruptions of volcanoes in the Pacific Ring of Fire and Iceland in 2006–2011. Since the second half of the 1990s we have recorded an increasing TO trend, equalling 0.65 DU/year for the period 1996–2013.

In the report, we analyze the dada of lidar measurements of aerosol and ozone optical characteristics in the stratosphere over Tomsk. The vertical ozone profiles, obtained in March 2017 with the help of differential absorption lidar at the Siberian Lidar Station, are compared with profiles, retrieved according to data from Meteorological Operational satellite programme (MetOp) satellite developed by the European Space Agency (ESA).

Understanding the cooling effect of recent volcanoes is of particular interest in the context of the post-2000 slowing of the rate of global warming. Satellite observations of aerosol optical depth above 15 km have demonstrated that small-magnitude volcanic eruptions substantially perturb incoming solar radiation. Here we use lidar, Aerosol Robotic Network, and balloon-borne observations to provide evidence that currently available satellite databases neglect substantial amounts of volcanic aerosol between the tropopause and 15 km at middle to high latitudes and therefore underestimate total radiative forcing resulting from the recent eruptions. Incorporating these estimates into a simple climate model, we determine the global volcanic aerosol forcing since 2000 to be −0.19 ± 0.09 Wm−2. This translates into an estimated global cooling of 0.05 to 0.12°C. We conclude that recent volcanic events are responsible for more post-2000 cooling than is implied by satellite databases that neglect volcanic aerosol effects below 15 km.

This paper introduces the technique of retrieving the profiles of vertical distribution of ozone considering temperature and aerosol correction in DIAL sounding of the atmosphere. The authors determine wavelengths, which are promising for measurements of ozone profiles in the upper troposphere–lower stratosphere. An ozone differential absorption lidar is designed for the measurements. The results of applying the developed technique to the retrieval of the vertical profiles of ozone considering temperature and aerosol correction in the altitude range 6–15 km in DIAL sounding of the atmosphere confirm the prospects of ozone sounding at selected wavelengths of 341 and 299 nm with the proposed lidar. The 2015 ozone profiles retrieved were compared with satellite IASI data and the Kruger model.

In the report, we analyze the data of lidar measurements of optical characteristics of aerosol in the stratosphere over Tomsk; the analysis revealed the periods of elevated aerosol content after a series of explosive eruptions of volcanoes of the Pacific “Ring of Fire” and Iceland in 2006-2011. For these relatively weak eruptions (which injected to the stratosphere no more than 2 Mt of sulfur dioxide, serving the source for the sulfur acid aerosol formation), the periods of elevated aerosol content had been from a few months to half-year. Since 2012, a background state of aerosol loading had been established in the stratosphere over Tomsk. The regional empirical model of background stratospheric aerosol, developed by us for 2000-2008, was corrected to include data of measurements from 2012 to 2016.

Siberian Lidar Station created at V.E. Zuev Institute of Atmospheric Optics SB RAS and operating in Tomsk (56.5° N, 85.0° E) is a unique atmospheric observatory. It combines up-to-date instruments for remote laser and passive sounding for the study of aerosol and cloud fields, air temperature and humidity, and ozone and gaseous components of the ozone cycles. In addition to controlling a wide range of atmospheric parameters, the observatory allows simultaneous monitoring of the atmosphere throughout the valuable altitude range 0–75 km. In this paper, the instruments and results received at the Station are described.

The paper introduces the technique of recovering profiles of ozone vertical distribution considering temperature and aerosol correction in atmosphere lidar sounding by DIAL. The authors have determined wavelengths, promising to measure ozone profiles in the upper troposphere — lower stratosphere. To obtain promptly the results of the methodology the authors developed the software based on DIAL with user-friendly interface in the programming language C# using the lidar measurements. The recovered ozone profiles, resulting from the program operation, were compared with IASI satellite data and Kruger model. The results of applying the developed technique to recover the profiles of ozone vertical distribution considering temperature and aerosol correction in the altitude range of 6–18 km in lidar atmosphere sounding by DIAL confirm the prospects of using the selected wavelengths of ozone sensing 341 and 299 nm in the ozone lidar.

The feasibility of remote sensing of gas components of the atmosphere by a differential absorption lidar technique using a multiple-wavelength self-terminating SrI and SrII vapor laser has been determined. Development and construction of a sealed-off strontium vapor laser for remote sensing of the atmosphere is reported. This is an outgrowth of broad studies on laser designs, pumping and operating conditions, etc. Informative strontium laser wavelengths to be used for sensing trace gas species have been identified, and laser attenuation by gas components of the atmosphere has been measured. Test experiments have been performed on lidar sensing of water vapor in boundary atmospheric layers.

We present the results of lidar measurements of the vertical distribution of optical parameters of anomalous aerosol formations in the atmosphere and the polarization state of backscattered sounding radiation, obtained in Tomsk (56.48°N; 85.05°E) and Surgut (61.25°N; 73.43°E) in April–May 2010. Data from measurements using back trajectory analysis of atmospheric air-mass transport according to the NOAA HYSPLIT MODEL showed that the observed anomalous aerosol formations were due to transport of the products of the Eyjafjallajokull volcano eruption in Iceland (April 14, 2010). First traces of the volcanic eruption were recorded in the troposphere over Tomsk on April 19. The volcanic aerosol persisted in the troposphere for about 10 days in total; it penetrated into the stratosphere insignificantly and could not have noticeable long-term radiation and thermal effects.

The lidar measurements (Tomsk:56.5∘N;85.0∘E) of the optical characteristics of the stratospheric aerosol layer (SAL) in the volcanic activity period 2006–2011 are summarized and analyzed. The background SAL state with minimum aerosol content, observed since 1997 under the conditions of long-term volcanically quiet period, was interrupted in October 2006 by series of explosive eruptions of volcanoes of Pacific Ring of Fire: Rabaul (October 2006, New Guinea); Okmok and Kasatochi (July-August 2008, Aleutian Islands); Redoubt (March-April 2009, Alaska); Sarychev Peak (June 2009, Kuril Islands); Grimsvötn (May 2011, Iceland). A short-term and minor disturbance of the lower stratosphere was also observed in April 2010 after eruption of the Icelandic volcano Eyjafjallajokull. The developed regional empirical model of the vertical distribution of background SAL optical characteristics was used to identify the periods of elevated stratospheric aerosol content after each of the volcanic eruptions. Trends of variations in the total ozone content are also considered.

At the Siberian Lidar Station of the Zuev Institute of Atmospheric Optics (Tomsk) (56.5°N, 85.0° E), a lidar has been developed for measuring the vertical distribution of ozone in the upper troposphere-lower stratosphere in order to study the ozone dynamics in the tropopause region and the troposphere-stratosphere exchange. In sensing performed by the method of differential absorption and scattering, a pair of wavelengths of 299/341 nm is used, which correspond to the first and second Stokes components of converted radiation of the fourth harmonic of the pumping radiation from a Nd:YAG laser (266 nm) on the basis of the effect of stimulated Raman scattering in hydrogen.

A three-frequency lidar developed at the Siberian Lidar Station of the Zuev Institute of Atmospheric Optics (Siberian Branch, Russian Academy of Sciences) at Tomsk (56.5° N, 85.0° E) is described. The lidar is intended for sensing the microstructure characteristics of stratospheric aerosol at wavelengths of 355, 532, and 683 nm, which are, respectively, the third and second radiation harmonics of a Nd:YAG laser and the first Stokes component of conversion of laser radiation at a wavelength of 532 nm in hydrogen on the basis of the stimulated Raman scattering (SRS) effect. Knowledge of microstructure characteristics of the stratospheric aerosol is necessary for studying its influence on the radiation-temperature and chemical balance of the entire atmosphere. Some results of full-scale lidar measurements are presented.

The results of lidar observations of stratospheric aerosol perturbations for the period of July–November 2008 at three lidar stations of the CIS-LiNet network in Tomsk, Minsk, and Vladivostok are presented along with the results obtained in the Gobi Desert during a research expedition. The behavior of stratospheric profiles of the scattering ratio R(H) (ratio of the total aerosol and molecular backscattering coefficient to the molecular backscattering coefficient) is analyzed at different wavelengths characterizing the aerosol stratification in the stratosphere. The transport of air masses in the stratosphere is studied by the method of direct and backward trajectories using the NOAA HYSPLIT model. It is shown that stratospheric aerosol perturbations are connected with explosive eruptions of volcanoes of the Aleutian islands Okmok (53.4° N, 168.1° W; July 12, 2008) and Kasatochi (52.2° N, 175.5° W; August 6–8, 2008).

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.

We consider the results of remote spectrophotometric and lidar measurements of the total ozone and nitrogen dioxide contents and temperature, obtained at the Siberian Lidar Station (SLS) of V.E. Zuev Institute of Atmospheric Optics, Siberian Branch, Russian Academy of Sciences (Tomsk: 56.5°N; 85.0°E) in comparison with the results of analogous satellite measurements.The ground-based measurements of the total ozone (TO) content are performed with the help of М-124 ozonometer; and the measurements of the nitrogen dioxide (NO 2 ) content are carried out with automatic spectrophotometer. The groundbased lidar measurements of temperature are conducted on the basis of SLS measurement complex. These measurements are compared with data of balloon-sonde and satellite measurements. The satellite measurements are performed by the TOMS and IASI instrumentation.

We consider the results of long-term remote optical monitoring, obtained at the Siberian Lidar Station of Institute of Atmospheric Optics, Siberian Branch, Russian Academy of Sciences in Tomsk (56.5 °N, 85.0 °E). The scattering characteristics of stratospheric aerosol layer, obtained according to data of lidar measurements since 1986, are presented. We analyze the trends of changes in the total ozone (TO) content over Tomsk for the period 1996-2013 according to data of spectrophotometric measurements with employment of TOMS satellite data for the period 1979- 1994. We determined the periods of elevated content of stratospheric aerosol over Tomsk after a series of explosive eruptions of volcanoes of Pacific Ring of Fire and Iceland in 2006-2011. Since the second half of 1990s, researchers record an increasing TO trend, equaling 0.65 DU/yr for the period 1996-2013.

The Siberian Lidar Station created at V.E. Zuev Institute of Atmospheric Optics and operating in Tomsk (56.5° N, 85.0° E) is a unique atmospheric observatory. It combines up-to-date instruments for remote laser and passive sounding for the study of aerosol and cloud fields, air temperature and humidity, and ozone and gaseous components of the ozone cycles. In addition to controlling a wide range of atmospheric parameters, the observatory allows simultaneous monitoring of the atmosphere throughout the valuable altitude range 0–75 km. In this paper, the instruments and results received at the Station are described.

We describe an ozone lidar and consider an algorithm for retrieving the ozone concentration, taking into consideration the aerosol correction. Results of lidar measurements at wavelengths 299 and 341 nm well agree with model estimates, indicating that ozone is sensed with acceptable accuracies in the altitude range of about 6-18 km. It should be noted that the retrieved profiles of altitude distribution of ozone concentration more closely resemble those from satellite data than according to Krueger model. A lidar is developed and put into operation at Siberian Lidar Station (SLS) to measure the vertical ozone distribution (VOD) in the upper troposphere-lower stratosphere. Sensing is performed according to the method of differential absorption and scattering at wavelength pair 299/341 nm, which are respectively the first and second Stokes components of stimulated Raman scattering (SRS) conversion of the fourth harmonic of Nd:YAG laser (266 nm) in hydrogen.

We summarize and analyze the lidar measurements (Tomsk: 56.5°N; 85.0°E) of the optical characteristics of the stratospheric aerosol layer (SAL) in the volcanic activity period 2006-2011. The background SAL state with minimal aerosol content, which was observed since 1997 under the conditions of long-term volcanically quiescent period, was interrupted in October 2006 by a series of explosive eruptions of volcanoes of the Pacific Ring of Fire: Rabaul (October 2006, New Guinea); Okmok and Kasatochi (July-August 2008, Aleutian Islands); Redoubt (March-April 2009, Alaska); Sarychev Peak (June 2009, Kuril Islands), and Grimsvotn (May 2011, Iceland). A short-term and minor disturbance of the lower stratosphere was also observed in April 2010 after eruption of the Icelandic volcano Eyjafjallajokull. The developed regional empirical model of the vertical distribution of background SAL optical characteristics was used to identify the periods of elevated stratospheric aerosol content after each of the volcanic eruptions.

Based on analysis of data of lidar, spectrophotometric, and satellite measurements of integrated content of stratospheric ozone and aerosol for period 1986-2002 for observation site in Tomsk (56.48°N, 85.05°E), earlier we showed the presence of quasibiennial oscillation (QBO) of variations of their integrated content. The report analyzes data of lidar measurements of ozone and aerosol vertical distributions for background stratospheric state under conditions of extended volcanically quiet period 1996-2005. For analysis, we averaged profiles corresponding to easterly and westerly QBO phases, which were determined from monthly mean zonal wind components in the equatorial stratosphere. Larger aerosol content is observed in westerly QBO phases, and larger ozone content in easterly phases, in correspondence with views on general stratospheric circulation. Differences are most marked in the lower stratosphere, up to heights about 22 km. In the lower stratosphere, we also observe insignificantly larger aerosol content in winter-spring than summer-fall period. The presence of seasonality and quasibiennial oscillation, with increase of aerosol content at midlatitudes in periods of intensification of winter-spring meridional transport from tropical belt to midlatitudes and in westerly QBO phases, is an evidence in favor of hypothesis on the presence of tropical reservoir of background stratospheric aerosol.© (2006) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

First results of operational retrieval of atmospheric ozone profile from the Moderate Resolution Imaging Spectroradiometer (MODIS) infrared radiances over Siberian Region are presented. Nearly identical copies of MODIS are operating onboard the Earth Observing System (EOS) Tena and Aqua satellites. MODIS images have been collected using EOScan receiving station located in Barnaul. The modified Product Generation Executable (PGE) 03 code, including synthetic regression retrieval algorithm, PGE 02 and the International MODIS/AIRS Processing Package (IMAPP) have been used to retrieve the vertical ozone distributions under clear-sky conditions. Evaluation of retrieved ozone profiles is performed by a comparison with retrievals from lidar observations, the Stratospheric Aerosol and Gas Experiment III (SAGE 111)/Meteor-3M and the Atmospheric Infrared Sounder (AIRS)/Aqua sensors. We demonstrate, that the MODIS mixing ozone ratio (in ppmv) and additionally measured temperature information will be useful tools in regional stratospheric ozone studies. The main role of MODIS will be the monitoring of the ozone trends in the stratosphere at the scale with 5 km x 5 km resolutions.

At Siberian Lidar Station (SLS) in Institute of Atmospheric Optics, Siberian Branch of Russian Academy of Sciences, Tomsk (56.5 °N; 85.1°E) we perform regular lidar measurements of the profiles of vertical distribution of optical characteristics of stratospheric aerosol at wavelength 532 nm with receiving telescope of a diameter of 03. m. The temperature profile is measured in the altitude interval 10-70 km: from molecular backscattering signal at wavelength 532 nm in altitude range 30-70 km and from signal of Raman scattering by nitrogen at wavelength 607 nm in altitude range 10-30 km with receiving telescope of a diameter 2.2m. In this paper we analyze the data of long-term (since 1986) lidar observations of stratospheric aerosol layer, performed at Siberian Lidar Station and data of expedition measurements in summer-fall periods of 2001-3003, obtained in Siberian region from middle to subpolar latitudes (from 52° to 69°N and from 73° to 106° E). Main attention is paid to analysis of data of last years of measurements obtained under conditions of “new” background period of long-term absence of explosive volcanic eruptions (last observed in June 1991).