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2022 year, number 10
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M.V. Tarasenkov, V.V. Belov, E.S. Poznakharev
V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, Tomsk, Russia
Keywords: atmosphere, scattered laser radiation, NLOS optical communication, visible and UV wavelength regions, unmanned aerial vehicle
Abstract >>
A model of an optical communication atmospheric channel on scattered radiation between the ground surface and an unmanned aerial vehicle (UAV) is considered. Changes in the useful signal attenuation, the minimum energy per source pulse providing the stable link, and the maximum information transfer rate versus the optical and geometrical conditions of forming the communication channel are estimated. Based on the results, recommendations are formulated for the choice of optimal schemes of optical communication systems on scattered radiation with UAV.
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Yu.V. Kistenev1,2, A. Cuisset3, O.A. Romanovskii2, A.V. Zherdeva1
1National Research Tomsk State University, Tomsk, Russia
2V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, Tomsk, Russia
3Université du Littoral-Cöte d’Opale, Dunkerque, France
Keywords: trace atmospheric gas, “water - atmosphere” interface, laser absorption spectroscopy, IR spectral range
Abstract >>
Trace atmospheric gases (TAGs) emitted by the Earth's water surface significantly impact the chemical processes in the atmosphere, weather formation, and the global climate change. The main TAGs emitted from the ocean surface and wetlands are described and analyzed. The laser absorption spectroscopy technique for local/remote gas-analysis suitable for detection of several TAGs is considered, including cavity-ring down spectroscopy and optical-acoustic spectroscopy. Approaches to the development of laser absorption spectroscopy tools for the control of a large number of TAGs using an optical parametric oscillator as a tunable laser source are considered, as well as examples of their implementations.
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R.Sh. Tsvyk, N.A. Vostretsov
V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, Tomsk, Russia
Keywords: fluctuation, scattered radiation, focused beam, spectrum, rain, drizzle, fog, haze, turbulence
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The results of experimental studies of the spectra of fluctuations of the scattered radiation intensity of a laser beam propagating through the surface atmosphere in rains, drizzle, haze, and fog are presented. The laser beam radiation was focused at the end of a 130 m path. The intensity fluctuations were measured at a distance of 10 mm from the focal spot, in the region of radiation scattered on the particles in the atmosphere. The spectrum of scattered radiation fluctuations U ( ƒ ) = ƒW ( ƒ )/∫ W ( ƒ ) dƒ in rain, drizzle, and haze is characterized by four parameters: the maximum frequency ƒ max, the inclination of the low-frequency part of the spectrum 1 > γv > 0 at ƒ < ƒ max and two inclinations of the high-frequency region γv = -2.5…-5/3 and γv1 = -3…-5 at ƒ > ƒ max; and in a weak fog, mainly by two negative inclinations γv = -0.5 and γv1 = -4…5. The frequency of the scattered field spectrum maximum is determined by the interaction of the vortex field of wind speed fluctuations, the field of particle size and mass distributions, and the drag coefficient.
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V.V. Polkin1, L.P. Golobokova2, I.A. Kruglinsky1, A.O. Pochufarov1, S.M. Sakerin1, O.I. Khuriganova1,2
1V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, Tomsk, Russia
2Limnological Institute of the Siberian Branch of the RAS, Irkutsk, Russia
Keywords: White Sea, atmospheric aerosol, microphysical characteristics, ionic composition
Abstract >>
The paper presents the results of a statistical generalization of the microphysical characteristics and ionic composition of the aerosol in the atmosphere of the White Sea obtained during the expeditions of 2003-2021. Based on the recalculation of the measurement results using a uniform data filtering algorithm, the total number concentration of particles with a radius of 0.2-5 μm, the volumes of particles of fine and coarse dispersed drive aerosol with a radius of less than and more than 0.5 μm, the distribution function of particles by volume are considered, mass concentrations in the composition were estimated aerosol of eight water-soluble ions Ca2+, Mg2+, Na+, K+, NH4+, NO3-, Cl-, and SO42-. Spatial inhomogeneities and causes of anomalously high concentrations and ionic composition of the aerosol are analyzed.
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I.N. Smalikho, V.A. Banakh, I.A. Razenkov, A.A. Sukharev, A.V. Falits, A.M. Sherstobitov
V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, Tomsk, Russia
Keywords: coherent Doppler lidar, wind velocity
Abstract >>
A pulsed coherent Doppler lidar (PCDL) developed at the Wave Propagation Laboratory of Institute of Atmospheric Optics, Siberian Branch, Russian Academy of Sciences (LRV lidar) was tested in two experiments carried out in 2021 at the Basic Experimental Observatory of Institute of Atmospheric Optics SB RAS and on the coast of Lake Baikal. In those experiments, a serial Stream Line PCDL (HALO Photonics, Great Britain) was also involved. The comparative analysis of estimates of the average horizontal and vertical wind speeds from measurements with Stream Line and LRV lidars showed a good agreement between the results (the correlation coefficient of the estimates is 0.98 with a 30-minute averaging of the data).
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V.V. Kuskov, V.A. Banakh, E.V. Gordeev, A.N. Shesternin
V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, Tomsk, Russia
Keywords: laser beam, wavefront, atmospheric backscatter, misalignment of optical axes, compensation, image center of gravity
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The results of atmospheric studies of a possibility of compensating for the beam deviation from a direction specified by means of shifting the energy center of gravity of the optical image of the beam scattering volume are presented. The experiments were carried out with collimated and focused beams. The image of the laser spot on the scattering atmospheric layer was recorded by an array detector located in the sharp-image plane of a telescope. The laser beam propagation direction was controlled with a rotary mirror. It is shown that the beam deviation can be compensated for accurate to several microradians.
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B.D. Belan, G.A. Ivlev, A.V. Kozlov, D.A. Pestunov, T.K. Sklyadneva, A.V. Fofonov
V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, Tomsk, Russia
Keywords: atmosphere, radiation, albedo, radiation balance
Abstract >>
Variations in solar radiation in the wavelength ranges λ = 0.285 ÷ 2.8 mm, λ = 0.280 ÷ 0.400 mm, and λ = 0.280 ÷ 0.315 mm are analyzed on the basis of ground-based measurements at the Fonovaya observatory in 2021. The results of calculations of the radiation balance and albedo of the underlying surface are presented. During the period of a stable snow cover, from November to March, the daily average radiation balance is shown to be -1.20 ± 1.18 MJ/m2, and in the absence of snow, from May to September, +8.83 ± 4.49 MJ/m2. The daily solar radiation absorption by the Earth's surface is estimated. During the period of a stable snow cover, from December to March, the daily solar radiation absorbed by the Earth's surface did not exceed 2 MJ/m2, and it varied from to 25 MJ/m2 in summer.
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K.B. Moiseenko1, A.V. Vasileva1, A.I. Skorokhod1, Yu.A. Shtabkin1, I.B. Belikov1, A.Yu. Repin2
1A.M. Obukhov Institute of Atmospheric Physics Russian Academy of Sciences, Moscow, Russia
2E.K. Fedorov Institute of Applied Geophysics of the Russian Academy of Sciences, Moscow, Russia
Keywords: atmospheric boundary layer, ozone generation, peroxy radical, volatile organic compound, ZOTTO Tower
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The rates of ozone production ( P ) and sink ( L ) and total peroxide (OX) content are assessed with the use of the photostationary state approach from measurements of ozone (O3) and nitrogen oxides (NO, NO2) at Zotino Tall Tower Observatory (ZOTTO), central Siberia, in 2007-2014. Mean diurnal cycles of the above quantities for May - September cloud-free days peak at 6 ppb/hour ( P ), 1.4 ppb/hour ( L ), and 115 ppb ([OX]) between 11:00 and 15:00 local time. The linear dependence of P on [NOx] is derived in the range of measured NOx mixing ratios from 0.2-0.8 ppb, suggesting for NOx-limiting conditions of ozone production, with the slope rate P (O3)/[NOx] estimated at 13 (ppb/h)/ppb. The estimated high OX levels along with the condition P >> L manifest for high rates of the in-situ oxidation of biogenic volatile organic compounds and ozone generation. The surface air layer in boreal forest around the site can be considered an ozone source for the atmospheric boundary layer over remote central Siberia at NOx levels characteristic for both weakly polluted and clean (background) air masses.
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A.P. Luzhetskaya1, E.S. Nagovitsyna1,2, E.V. Omelkova1, V.A. Poddubny1
1Institute of Industrial Ecology Ural branch of RAS, Ekaterinburg, Russia
2Institute of Natural Sciences, Ural Federal University named after the first President of Russia B.N. Yeltsin, Ekaterinburg, Russia
Keywords: mass concentration of aerosol particles ÐÌ2.5, aerosol optical depth, monitoring of the atmosphere, empirical statistical model, regression analysis
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Measurements of aerosol parameters in the surface air layer with sets of Panasonic PM2.5 optical sensors and throughout the atmospheric column by the photometric method at urban and background observation sites in the Middle Urals for 2016-2019 are analyzed. The features of the intraannual and diurnal variations in aerosol parameters in the surface air layer and in the atmospheric column are compared. Correlations between the PM2.5 concentration, AOD, and meteorological parameters in the two regions are also studied. Multivariate regression models for estimating the logarithm of PM2.5 concentration ensure much higher quality than single-factor models. The significant predictors are determined: boundary layer height (blh, m), ln AOD, normalized relative vegetation index (NDVI), relative air humidity (Hu, %), and air pressure ( P , Pa).
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V.I. Mankovskiy
Marine Hydrophysical Institute National Academy of the RAS, Sevastopol, Russia
Keywords: light scattering phase function, asymmetry coefficient, particle scattering, molecular scattering, wavelength, spectral variability
Abstract >>
Data on the spectral variability of the coefficient of asymmetry of the light scattering phase function in the water of Lake Baikal obtained by Tarashchansky B.A. et al. in the work “Methods and Results of Monitoring the Optical Characteristics of the Water Environment of the Baikal Neutrino Telescope, Carried out by a Stationary Deep-Sea Device ASP-15” are analyzed. It is shown that these data contradict the theoretical and experimental results. The model calculation of the spectral variability of the coefficient of asymmetry of the light scattering phase function in the waters of Lake Baikal has been performed.
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L.A. Bolbasova, V.P. Lukin
V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, Tomsk, Russia
Keywords: laser guide star, adaptive optics, atmospheric turbulence
Abstract >>
The work is devoted to the application of laser guide stars (LGS) technology for the adaptive optics system of a ground-based telescope. The results of the study of the possibilities of correcting the global wavefront tilt with the use of LGS are presented. To approaches are compared: polychromatic LGS, where the correction signal is a difference random refraction due to the atmosphere for different optical radiation wavelengths, and traditional monochromatic LGS, where an LGS is considered as a point source with a random center. The calculations were performed in the approximation of the Huygens-Fresnel method. It is shown that in this approximation, the signal from a monostatic monochromatic LGS used to correct the global wavefront tilt is comparable to the signal from a polychromatic LGS. Seasonal changes in the concentration and altitude of the mesospheric sodium layer, which determines the characteristics of sodium LGS, are estimated for Russian observatories.
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D.M. Ezhov1, D.M. Lubenko2, A.A. Mamrashev3, Yu.M. Andreev1,4
1National Research Tomsk State University, Tomsk, Russia
2High Current Electronics Institute of the Siberian Branch of the RAS, Tomsk, Russia
3Institute of Automation and Electrometry of the Siberian Branch of the RAS, Novosibirsk, Russia
4Institute of Monitoring of Climatic and Ecological Systems of the Siberian Branch of the Russian Academy of Sciences, Tomsk, Russia
Keywords: nonlinear crystal, lithium triborate, THz range, temperature dependence, refractive index, difference frequency generation, birefringence
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Using nonlinear LBO crystals of 30 × 30 × 10 mm3 in size, the spectral-temperature dependences of refractive indices in the long-wavelength part of the THz range 0.05-0.5 THz are obtained by means of terahertz time-domain spectroscopy under heating from 20 to 200 °C. Intersection of spectral dependences of the refractive index components nx and ny at ~ 84 °C is found. The results can be used for selection of types and phase-matching conditions for frequency conversion into long-wavelength part of the THz range, which is prospective for monitoring the gas composition of the atmosphere due to weak influence of the aerosol attenuation.
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