|
|
2018 year, number 11
|
V.V. Veretennikov, S.S. Men’shchikova, V.N. Uzhegov
V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, 1, Academician Zuev square, Tomsk, 634021, Russia
Keywords: коэффициент аэрозольного ослабления света, микроструктура приземного аэрозоля, обратные задачи, aerosol extinction coefficient, near-surface aerosol microstructure, inverse problem
Abstract >>
Results of retrieval of microstructure parameters of near-surface aerosol in the summer period from spectral measurements of the aerosol extinction coefficient are presented. Experimental data were obtained in Tomsk at a horizontal path using an atmospheric transmittance meter at 11 wavelengths in the range from 0.45 to 3.91 μm. The numerical algorithm, based on the method of integral distributions, was used to solve the inverse problem. In the first part of the work, the variability of the geometric cross section of particles of the fine and coarse fractions and the total ensemble is analyzed. The influence of smoke pollution of atmosphere on the variation in microstructure parameters is considered. It is shown that fine particles make the main contribution (73-77%) to the total cross section of near-surface aerosol. The coefficients of variation of the cross sections of the particles are high in the range 53-61% for the fine and 53-69% for the coarse fractions of aerosol in monthly intervals without taking into account the influence of the smoke. Correlations between the aerosol extinction coefficients at different wavelengths and the aerosol microstructure parameters retrieved are investigated.
|
|
V.V. Veretennikov, S.S. Men’shchikova, V.N. Uzhegov
V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, 1, Academician Zuev square, Tomsk, 634021, Russia
Keywords: коэффициент аэрозольного ослабления света, микроструктура приземного аэрозоля, объемная концентрация, средний радиус частиц, обратные задачи, aerosol extinction coefficient, near-surface aerosol microstructure, volume concentration, mean radius of particles, inverse problem
Abstract >>
The variability of the volume concentration and the mean radius of the fine and coarse fractions of near-surface aerosol is studied based on solution of the inverse problem for spectral measurements of aerosol extinction coefficient. It is shown that coarse particles make the main contribution (80%) to the total volume of the near-surface aerosol. The mean radius of fine particles varies in the range from 0.08 to 0.25 μm. The range of variation in the mean radius of the coarse aerosol is 1.06-3 μm. The influence of atmosphere smoke on the variation of microstructure parameters of the aerosol is considered. The variability of the retrieved microstructure parameters of near-surface aerosol is compared with similar results obtained from solar spectrophotometry.
|
|
D.N. Troshkin, V.E. Pavlov
Institute for Water and Environmental Problems of the Siberian Branch of the RAS, 656038, Barnaul, 1, Molodezhnaya str. IWEP SB RAS
Keywords: полуостров Ямал, Обская, Гыданская и Байдарацкая губы, функции распределений оптических толщ облаков, Yamal Peninsula, the Gulf of Ob, Khalmyer Bay, Baidaratskaya Bay, probability density of clouds’ optical thickness
Abstract >>
The statistical analysis of summer cloud optical thickness over three geographically restricted zones in the region of the Ob Bay (dry and wet zones, coordinates are given) is performed with the use of ENVISAT-based experimental data on the cloud optical thickness obtained in 2008-2011. Type of functions of probability density of cloud optical thickness for each zone is determined. In logarithmic coordinates, each of these functions has several (3-4) maxima, indicating the occurrence of individual modes. The functions are approximated by a set of normal logarithmic distributions with certain parameters. The parameters prove to be well repetitive from year to year. There are three modes above the low-watered western zone, while in the eastern zones, where full-flowing rivers with relatively warm waters run from the south, they increase to four. On the authors’ opinion, water evaporation with subsequent condensation promotes the formation of an additional mode with low optical thickness. Anthropogenic emissions, which increase the number of condensation nuclei in the eastern zones, may also play a specific role in the process of enhanced condensation. Distribution function curves and tables with parameters are presented. Such data can be useful for calculations on radiation regime for small Yamal areas.
|
|
G.A. Kaloshin
V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, 1, Academician Zuev square, Tomsk, 634021, Russia
Keywords: микрофизика и оптика аэрозоля, рассеяние Ми, ветровой режим, разгон, параметризация, моделирование, программа, microphysics and optics of aerosol, Mie scattering, wind mode, fetch, parameterization, modeling, software
Abstract >>
MaexPro aerosol model of marine and coastal surface layer is presented. It is based on long-term observations of the particles sizes distribution in the 0.01-100 mm size range. A key feature of the model is the parameterization of the amplitude and width of modes of the aerosol size distribution function (ASDF) as functions of fetch and wind speed. The ASDF form and dependences on the altitude above sea level and relative humidity are studied. An expression is derived for the altitude profile of the aerosol extinction coefficient. Significant differences in its spectra at different altitudes are shown, the most pronounced in the altitude range from 0 to 10 m due to the gravitational effect on the medium and coarse fractions of the marine salt aerosol (MSA) particles. The model allows calculation of optical indexes of MSA particles versus the humidity in the wavelength range 0.2-16 mm. The domain of applicability of the model is determined.
|
|
V.A. Banakh, A.V. Falits
V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, 1, Academician Zuev square, Tomsk, 634055, Russia
Keywords: когерентный лидар, усиление обратного рассеяния, оптическая турбулентность, моделирование, coherent lidar, simulation, refractive turbulence, backscatter amplification
Abstract >>
The results of measurement of signal-to-noise ratio of a coherent lidar echo signal scattered by a diffuse screen are presented. Measurements were carried out under different refractive turbulence strength in the atmosphere. It is shown for the first time in the experiment that the mean power of echo signal of a coherent lidar increases with the turbulence strength.
|
|
T.K. Sklyadneva, B.D. Belan, T.M. Rasskazchikova, V.G. Arshinova
V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, 1, Academician Zuev square, Tomsk, 634055, Russia
Keywords: синоптические процессы, циклон, антициклон, воздушная масса, synoptic process, cyclone, anticyclone, air mass
Abstract >>
Synoptic processes observed in Tomsk region between 1993 and 2016 are analyzed. A significant decrease in the difference in the frequency of cyclones and anticyclones over the past decade is revealed. There is a tendency to decline in the frequency of Arctic air mass invasion and growth of subtropical and tropical ones.
|
|
N.E. Chubarova1, Yu.M. Timofeev2, Ya.A. Virolainen2, A.V. Polyakov2
1LomonosovMoscow State University, GSP-1, Leninskie Gory, Moscow, 119991, Russia
2Saint-Petersburg State University, University Embankment, 7-9, St. Petersburg, 199034
Keywords: УФ-радиация, озоновые дыры, УФ-индекс, УФ-ресурс, UV radiation, ozone holes, UV index, UV resource
Abstract >>
Calculations of UV radiation for the regions of Russia, where anomalies of the total ozone content were observed in the first quarter of 2016, are performed. Ozone depletion in the winter in the Northern regions of Siberia, even to the levels of the so-called ozone hole is not critical. However, much weaker ozone variations in the early spring can lead to dangerous levels of erythemal UV radiation, when one need in protection from ultraviolet radiation.
|
|
P.G. Kovadlo1, V.P. Lukin2, A.Yu. Shikhovtsev1
1Institute of Solar-Terrestrial Physics of the Siberian Branch of the RAS, 664033, Irkutsk, 126a, Lermontova str
2V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, 1, Academician Zuev square, Tomsk, 634055, Russia
Keywords: турбулентность, эффективная скорость турбулентных течений, эффективная высота турбулентности, turbulence, effective turbulence velocity, effective turbulence height
Abstract >>
The work is aimed at the improvement of the model of turbulent atmosphere at the Large Solar Vacuum Telescope site using the analysis of the energy turbulence spectrum in a wide range of frequencies and deformations of the vertical profile of the structure characteristic of the air refraction index in the atmospheric boundary layer (up to 1 km) depending on the surface turbulence energy.
|
|
V.A. Banakh, A.N. Kudryavtsev, V.M. Sazanovich, R.Sh. Tsvyk
V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, 1, Academician Zuev square, Tomsk, 634055, Russia
Keywords: широкоформатные оптические пучки, импульсно-периодическое излучение, непрерывное излучение, мощность, энергия, измерительные блоки, large-format optical beams, pulsed-periodic radiation, continuous radiation, power, energy, measuring units
Abstract >>
A device for measurements of the power/energy of large-format optical (laser) radiation beams is described. It includes two interchangeable measuring units, one for measurements of the energy in each pulse of a pulsed-periodic laser, and the second, for the continuous radiation power measurements.
|
|
A.A. Sukharev
V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, 1, Academician Zuev square, Tomsk, 634055, Russia
Keywords: оживальное тело, средняя интенсивность, однородная среда, ogival body, mean intensity, homogeneous medium
Abstract >>
An optical model of a shock wave formed due to supersonic airflow around a body of an ogival form is developed. Mean values of airflow parameters were calculated from the Navier-Stokes equations using the CFD Fluent 6.0 software package, taking into account the compressibility of the gas. It is shown that the maximum values of the structural characteristic are several orders of magnitude larger than the values typical for the unperturbed shock wave of the atmosphere. Results of calculation of the mean intensity and deviation from the rectilinear direction of propagation of the optical beam crossing a shock wave at the beginning of a path in a homogeneous medium are presented. It is shown that an increase in the aircraft speed leads to an increase in the transverse dimensions of the beam due to diffraction. Magnitude of angular displacements of a beam crossing the shock wave depends only on the altitude above the Earth's surface at which the shock wave is formed. The impact of shock wave on the crossing beam decreases as the altitude increases.
|
|
V.A. Kapitanov, K.Y. Osipov
V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, 1, Academician Zuev square, Tomsk, 634055, Russia
Keywords: спектр поглощения, диодный лазер, оптико-акустический детектор, зеркальный модулятор, absorption spectrum, diode laser, photoacoustic detector, mirror modulator
Abstract >>
A softwave-controlled photoacoustic spectrometer is developed on the basis of TEC-520 diode laser (output power 30 mW, coarse tuning range 6060-6600 cm-1, line width ~ 5E-5 cm-1, fine tuning range 0 - 2.5 cm-1), WS-UIR laser wavelength meter (relative error Δλ/λ ~ 1E-8), and resonance photoacoustic detector with threshold sensitivity ~ 3E-10 W × cm-1 × Hz-1/2. Procedures and computer programs for spectra measurements and processing are developed. The results of the water vapor spectra measurements are presented.
|
|
V.I. Serdyukov, L.N. Sinitsa, A.A. Lugovskoi, N.M. Emelyanov
V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, 1, Academician Zuev square, Tomsk, 634055, Russia
Keywords: Фурье-спектроскопия, спектр поглощения, метан, Fourier spectroscopy, absorption spectrum, methane
Abstract >>
A low temperature vacuum cell 220 cm long with windows of quartz, ZnSe, and KBr has been developed for work with the Bruker IFS 125-M high resolution Fourier spectrometer providing a threshold sensitivity to absorption on the order of 10-7 cm-1. The cell allows recording the absorption spectra of gases in the temperature range from 200 to 296 K with the accuracy of 0.9 K in the region 1000-20000 cm-1.
|
|
