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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...

International audience; The change of the global climate is most pronounced in the Arctic, where the air temperature increases 2 to 3 times faster than the global average. This process is associated with an increase in the concentration of greenhouse gases in the atmosphere. There are publications predicting the sharp increase in methane emissions into the atmosphere due to permafrost thawing. Therefore, it is important to study how the air composition in the Arctic changes in the changing climate. In the Russian sector of the Arctic, the air composition was measured only in the surface atmospheric layer at the coastal stations or earlier at the drifting stations. Vertical distributions of gas constituents of the atmosphere and aerosol were determined only in a few small regions. That is why the integrated experiment was carried out to measure the composition of the troposphere in the entire Russian sector of the Arctic from on board the Optik Tu-134 aircraft laboratory in the period of 4 to 17 September of 2020. The aircraft laboratory was equipped with contact and remote measurement facilities. The contact facilities were capable of measuring the concentrations of CO2, CH4, O3, CO, NOx, and SO2, as well as the disperse composition of particles in the size range from 3 nm to 32 µm, black carbon, and organic and inorganic components of atmospheric aerosol. The remote facilities were operated to measure the water transparency in the upper layer of the ocean, the chlorophyll content in water, and spectral characteristics of the underlying surface. The measured data have shown that the ocean continues absorbing CO2. This process is most intense over the Barents and Kara seas. The recorded methane concentration was increased over all the Arctic seas, reaching 2090 ppb in the near-water layer over the Kara Sea. The contents of other gas components and black carbon were close to the background level. In bioaerosol, bacteria predominated among the identified microorganisms. In most samples, they were represented by coccal forms, less often spore-forming and non-spore-bearing rod-shaped bacteria. No dependence of the representation of various bacterial genera on the height and the sampling site was revealed. The most turbid during the experiment was the upper layer of the Chukchi and Bering seas. The Barents Sea turned out to be the most transparent. The differences in extinction varied by more than a factor of 1.5. In all measurements, except for the Barents Sea, the tendency of an increase in chlorophyll fluorescence in more transparent waters was observed.

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.

A series of laboratory experiments was carried out to measure the absorption of the IR OPO laser radiation by methane within a calibrated CH4:N2 molecular mixture in a gas cell. The results of measurements of the laser radiation absorption at sounding wavelengths selected are presented and compared with the calculation results. Backscattered signals in the 3.30–3.43 μm spectral range are detected and processed with the use of the IR OPO lidar system designed along a horizontal sounding path in the atmosphere. Based on the experimental results, the absorption coefficients are estimated and the CH4 concentrations along a 800 m surface path are retrieved in the spectral range under study with a spatial resolution of 100 m.

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.

A lidar system was designed on the basis of parametric light generation with nonlinear KTA and KTP crystals, which allow turning laser radiation in the near and mid infrared spectral regions. Lidar echoes were experimentally detected in the 1.8–2.5 and 3–4 μm wavelengths ranges.

We presented the lidar measurements of vertical ozone distribution (VOD) over Tomsk, performed at Siberian Lidar Station (56.5oN, 85.0oE) in 2018 at the altitudes of the upper troposphere - stratosphere. The results of lidar sensing of ozone, carried out according to the method of differential absorption and scattering with the temperature and aerosol correction, are compared with data from MetOp and AURA meteorological satellites. The lidar/satellite data comparison is analyzed, as well as the dynamics of January ozone variations. An episode of recording ozone anomaly is shown against the background of Krueger midlatitude model.

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.

A differential absorption lidar system was designed on the basis of parametric light generation with nonlinear KTA and KTP crystals, which allow turning laser radiation in the near- and mid-IR spectral regions. Lidar echoes were experimentally detected in the 1.8–2.5 and 3–4 μm wavelengths ranges. The results of first in situ measurements of the methane concentration in the mid-IR are given.

A series of laboratory experiments out to measure the absorption of the OPO laser radiation by methane as part of a calibrated CH4: N2 molecular mixture in a gas cell has been carried. The experiments were carried out in the spectral range of 3.30–3.43 μm, in which there is a fairly strong absorption band of methane and there is no interfering absorption by water vapor and carbon dioxide. The results of measuring the absorption of laser radiation at selected sensing wavelengths and their comparison with the calculated data are presented. Using the developed OPO-lidar system, backscattered signals were received and processed in the range of the spectrum of 3.30–3.43 μm for the horizontal route of atmospheric sensing. Based on the experimental data obtained, the absorption coefficients were estimated and the CH4 concentrations were restored in the spectral range under study at a 800 m atmospheric path with a spatial resolution of 100 m.

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.

Data on the atmospheric gas concentrations can be received with high efficiency and on a large spatial scale only from remote laser sounding instruments. The remote laser techniques with the use of lidars are widely used in the study of the atmosphere and control of its state. The aims of this work are the design and test in numerical and field experiments of a DIAL OPO lidar system based on KTA and KTP crystals for gas analysis of the atmosphere. Lidar measurements of atmospheric gases in the near/mid infrared region have been numerically simulated. The differential absorption lidar system based on optical parametric oscillators with nonlinear KTA and KTP crystals which allow laser radiation tuning both in the near and in the middle IR spectral region is described; it allows tuning laser radiation in the near/mid-IR wavelength regions. Lidar echo signals have been experimentally recorded in the 1.8–2.5 and 3–4 m wavelength ranges. The results of H2O and CO2 profile measurements along the surface sounding path are presented.

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.

Prototypes of a typical automated station for monitoring the atmospheric composition and state, as well as lidars and sodars, have been designed and manufactured within the project, which are to be the components of monitoring stations. Experimental tests of the instruments confirmed their designed-in specifications and functions. For contact measurements of air parameters, a complex air monitoring station and an aerosol multiwave diffusion spectrometer have been also designed and manufactured in accordance with technical assignment requirements. The measurement results have shown a continuous increase in the concentrations of carbon dioxide and nitrous oxide, as well as a renewed increase in the methane concentration in the layer from 0 to 7 km.

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).

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.

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.

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 paper presents the results of DIAL measurements of the vertical ozone distribution. The ozone lidar operate as part of the measurement complex at Siberian Lidar Station (SLS) of V.E. Zuev Institute of Atmospheric Optics SB RAS, Tomsk (56.5ºN; 85.0ºE) and designed for study of the vertical ozone distribution in the upper troposphere–lower stratosphere. Most suitable wavelengths for measurements of ozone profiles are selected. We present an algorithm for retrieval of vertical distribution of ozone with temperature and aerosol correction during DIAL lidar sounding of the atmosphere. The temperature correction of ozone absorption coefficients is introduced in the software to reduce the retrieval errors. 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., {"references":["SAGE II (Stratospheric Aerosol and Gas Experiment II) http://sage.nasa.gov/missions/about-sage-ii/","V. D. Burlakov, S. I. Dolgii, A. V. Nevzorov, \"Modification of the measuring complex at the Siberian Lidar Station,\" Atmospheric and oceanic optics, vol. 44, no. 10, pp. 756-762, 2004.","E. Galani, D. Balis, P. Zanis, C. Zerefos, A. Papayannis, H. Wemli, and E. Gerasopoulos, \"Observations of stratosphere-to-troposphere transport events over the eastern Mediterranean using a ground-based lidar system,\" J. Geophys. Res., vol. 44, no. D12, P.STA12/1-STA12/10, 2003.","Nakazato Masahisa, Nagai Tomohiro, Sakai Tetsu, and Hirose Yasuo, \"Tropospheric ozone differential-absorption lidar using stimulated Raman scattering in carbon dioxide,\". Appl. Opt,. vol. 44, no. 12, pp. 2269-2279, 2007.","V. S. Bukreev, S. K. Vartapetov, I. A. Veselovskii, A. S. Galustov, Yu. M. Kovalev, A. M. Prokhorov, E. S. Svetogorov, S. S. Khmelevtsov, Ch. Kh. Li, \"Lidar system for sensing the stratospheric and tropospheric ozone on the basis of excimer lasers,\". Quantum Electronics, vol. 21, no. 6, pp. 591- 596, 1994.","H. Eisele, H. E. Scheel, R. Sladkovic, and T. Trickl, \"High resolution lidar measurements of stratosphere-troposphere exchange,\" J. Atmos. Sci., vol. 56, no. 3, pp. 319-330, 1999.","V. D. Burlakov, S. I. Dolgii, A. P. Makeev, A. V. Nevzorov, O. A. Romanovskii, O. V. Kharchenko, \"A differential-absorption lidar for ozone sensing in the upper atmosphere-lower stratosphere,\" Instruments and Experimental Techniques, vol. 53, no. 6, pp. 886-889, 2010.","A. V. Nevzorov, A. A. Nevzorov, O. A. Romanovskii, \"Software for retrieving the ozone altitude profiles from data of atmospheric laser sensing,\" Proc. SPI, vol. 9292, 92923L, 2014.","A. J. Krueger, R. A. Minzner, \"A mid-latitude ozone model for the 1976 U.S. standard atmosphere,\" J. Geophys. Res., vol. 81, no. D24, pp. 4477-4481, 1976."]}

In the present work it is demonstrated that a wideband CO laser operating at fundamental and overtone vibrational transitions is a promising source of laser radiation for remote laser sensing of the atmosphere. A compact slab RF-discharge CO laser has been designed. The optimal operating conditions are determined for this CO laser. In experiments, the maximum average output laser power was ∼12 W for lasing efficiency of ∼14%. Under fixed experimental conditions, stable lasing (with fluctuations of the output laser characteristics ≤5%) was observed during more than one hour, which suggests that we first excited the sealed-off mode of cryogenic slab RF-discharge CO laser. The frequency-selective mode was first obtained for this laser. Wavelengths for sensing of nitrous oxide, nitrogen dioxide, methane, formaldehyde, and some other gases on near-ground propagation paths are determined. Our experiments and calculations confirm that this CO laser is promising for laser gas analysis.

In the present work, systematic errors of lidar gas analysis in the atmosphere by the differential absorption lidar method in the near-and middle-IR ranges of the spectrum are analyzed. It is demonstrated that the systematic errors depend on many factors, including the meteorological parameters and concentrations of the examined gases along the sensing path, instability of the spectral parameters of laser radiation lines, shift of the absorption line centers caused by the air pressure, Doppler broadening of backscattered signals, and other sources of errors. Methods of error minimization in reconstructing lidar profiles of the examined atmospheric gas concentrations are suggested.

The paper presents the results of laboratory experiments on measurement of absorption and extinction of radiation of the overtone СО laser at wavelengths used for sensing of methane and N2 O in the mid-IR spectral range with the differential absorption (DIAL) method, as well as the concentrations of the studied gases reconstructed from the analysis of experimentally obtained absorption coefficients.

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.

The primary project objective was to accomplish the Complex Aerosol Experiment, during which the aerosol properties should be measured in the near-ground layer and free atmosphere. Three measurement cycles were performed during the project implementation: in spring period (April), when the maximum of aerosol generation is observed; in summer (July), when atmospheric boundary layer height and mixing layer height are maximal; and in late summer – early autumn (October), when the secondary particle nucleation period is recorded. Numerical calculations were compared with measurements of fluxes of downward solar radiation. It was shown that the relative differences between model and experimental values of fluxes of direct and total radiation, on the average, do not exceed 1% and 3% respectively.

The main aim of the research is to develop the technique for laser remote ozone sensing in the upper troposphere – lower stratosphere by differential absorption method for temperature and aerosol correction and analysis of measurement results. The authors have determined wavelengths, promising to measure ozone profiles in the upper troposphere – lower stratosphere. We present the results of DIAL measurements of the vertical ozone distribution at the Siberian lidar station in Tomsk. The recovered ozone profiles were compared with IASI satellite data and Kruger model.

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.

The applicability of a KTA crystal-based laser system with optical parametric oscillators (OPO) generation to lidar sounding of the atmosphere in the spectral range 3–4 μm is studied in this work. A technique developed for lidar sounding of trace atmospheric gases (TAG) is based on differential absorption lidar (DIAL) method and differential optical absorption spectroscopy (DOAS). The DIAL-DOAS technique is tested to estimate its efficiency for lidar sounding of atmospheric trace gases. The numerical simulation performed shows that a KTA-based OPO laser is a promising source of radiation for remote DIAL-DOAS sounding of the TAGs under study along surface tropospheric paths. A possibility of using a PD38-03-PR photodiode for the DIAL gas analysis of the atmosphere is shown.

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.

The primary objective of this complex aerosol experiment was the measurement of microphysical, chemical, and optical properties of aerosol particles in the surface air layer and free atmosphere. The measurement data were used to retrieve the whole set of aerosol optical parameters, necessary for radiation calculations. Three measurement cycles were performed within the experiment during 2013: in spring, when the aerosol generation is maximal; in summer (July), when atmospheric boundary layer altitude and, hence, mixing layer altitude are maximal; and in late summer/early autumn, during the period of nucleation of secondary particles. Thus, independently obtained data on the optical, meteorological, and microphysical parameters of the atmosphere allow intercalibration and inter-complement of the data and thereby provide for qualitatively new information which explains the physical nature of the processes that form the vertical structure of the aerosol field.