Home – Home – Jornals – Atmospheric and Oceanic Optics 2015 number 3

The method for determination of the mass concentrations of particulate matter smaller than 1.0, 2.5, 10, and 30 mm suspended in ground air was proposed. The method involves remote lidar sounding of the atmosphere at wavelengths λ = 0.355, 0.532, 1.064, 2.13 μm, recovering the spectral-spatial distributions of aerosol extinction coefficient from the lidar signal, and their converting to the spatial distribution of the mass concentrations of aerosol fractions based on regression relations between optical and microphysical characteristics of the aerosol. To improve the accuracy and stability of the solution of system of lidar equations the choice of calibration constants and the lidar ratio at the wavelengths of the sounding radiation is carried out taking into account the multicollinearity of the spectral aerosol extinction coefficients, which is expressed in the form of multiple regression equation. The regressions were obtained in the framework of World Meteorological Organization’s optical model of urban aerosol under wide variations in model parameters which characterize the particle size distribution and the complex refractive index of the aerosol matter. The numerical experiments on remote laser sounding of the mass concentration of aerosol fractions in the atmosphere have shown the robustness of the proposed method.

New experimental data that confirm episodic occurrence of the correlation of light backscattering lidar signals from a height region of 150–300 km with plasma content in nighttime ionosphere F₂ layer are presented. Analysis results of lidar observation data for 2008–2014 are shown. The conclusion is drawn that these correlations occur when additional sources for ionosphere ionization appear. A hypothesis that the possible mechanism for formation of these signals is the resonance scattering at excited ions of nitrogen atom is under discussion.

The results of the analysis of the radiation regime of Tomsk during the period of smoky haze from forest fires in Siberian region in July 2012 are presented. It is shown that in the presence of a smoky haze the total solar radiation is weakened by 45% on the average, and ultraviolet radiation, by 60–65% in comparison with similar periods with the typical background aerosol level. Parameters of smoky haze aerosol influencing the solar radiation absorption are determined. At strong smoke, the weakening of total radiation reached 70% and almost full weakening of UV radiation was observed.

Results of definition of the radiation balance and its components for Tomsk during 2004–2005 are presented. It is shown that the radiation balance of Tomsk is mainly positive during a year, and has negative values only from November to January. The maximum is observed in June; it made 176 W/m² in 2004 and 167 W/m² in 2005. The minimum is observed in December; it made –26 W/m² in 2004 and –41 W/m² in 2005.

Thermal balance of Tomsk is studied. A heat flux to the soil and an anthropogenic heat flux are calculated. The power contribution of phase transitions of water vapor to the overall thermal balance is estimated. It is shown that the main arrival of heat from March to September occurs at the expense of radiation components (75–100%). From December to February, the arrival of heat occurs generally at the expense of a turbulent heat flux and makes from 40 to 85% of the overall balance. During the autumn period before formation of snow cover, a heat flux from the soil is essential; it increases a turbulent heat flux in the atmosphere. During the warm period, the heat loss is distributed between a turbulent heat flux and heat for water evaporation (50/50%). The contribution of the heat coming into the soil is rather small (no more than 10% of the total loss). In spring, heat losses to snow cover melting appear; they can attain 50% of the total loss in separate months. In winter, the main heat losses fall on the radiation components.

The multiplicative approach to construction of numerical stochastic models of spatial and spatio-temporal fields of daily sums of liquid precipitation is considered. The approach is that the indicator fields of precipitation with the given correlation function and probabilities of precipitation and fields of the daily precipitation with the appropriate correlation function and one-dimensional distribution of probability are independently simulated. A final field is the product of these fields. The results of model verification and the results of research of properties of the statistical characteristics of extreme precipitation are presented.

The migration of heavy metals, the most dangerous contaminants of soil, are analyzed. The analysis of background contamination of soil with heavy metals showed that the invasion of dust haze from the south-western boundary results in increased concentration of Sc, Zn, Ni, Cu, Ca, Sr and Ge in aerosol particles in the dust haze, as compared with the soils of the zone of dust haze. In samples of dust haze aerosol, it was found a small quantity of K, Ti, Ni, V, and Cr, relative to Clarke, indicating a weak migration of these elements in the atmosphere. A strong migration of Co, Zn, Rb, As, and Sr elements in the atmosphere was found. Even more alarming is the accumulation of toxic elements such as Zn, Sb, and As, the content of which is up to ten times higher than Clarke.

The paper presents the results of dust load spatial distribution at Omsk city territory by the results of snow survey in 2013. The districts with low, middle, high, and very high pollution levels were revealed at the territory of the city. The most polluted districts are located at the territory of the east part of Omsk, where the biggest enterprises are located. The obtained data were compared with the dust data for other cities of the south part of the Western Siberia.

In the present work, peculiarities of the design and main characteristics of a series of airborne lidars developed at the Institute of Atmospheric Optics SB RAS are given. Physicotechnical parametres of lidars intended for sensing optically dense media, such as cloudiness, atmospheric pollution, and sea water are considered.

The description of the laser rangefinder monitoring system for Ust–Kamenogorsk shipping lock's wall deflections and the results of 8.5–years observations are presented. Ust–Kamenogorsk shipping lock has high-head single-lift chamber with 47 m depth. The wall deflections are caused by seasonal thermal deformations and dynamic loads related to the lock filling-emptying. The trend is found of the chamber width decrease with the rate of ~ 2.2 mm/year in the upper part of the lock. The effect of the lock filling-emptying process on the wall deflection dynamics was studied.

The results of experiments filamentation of terawatt femtosecond pulses of a Ti:Sapphire laser at atmospheric path length of 106 m using different spatial focus and power pulses are presented. The high efficiency control for the position and length of the field filamentation change the initial focus of the laser beam. The dependences of the length and position of filamentation on the initial degree of focus and power of the pulses, the number of filaments along the filamentation region are found. The obtained data on the length of the filamentation regionand the number of filaments with the results of earlier experiments and data of other authors were compared.

The paper presents the study of the 557.7 and 630–nm atomic oxygen emission responses to sharp variations in solar wind parameters, caused by shocks. The optical and geomagnetic data of the Eastern Siberia and interplanetary magnetic field and solar wind data were used for the analysis. It has been found that the considered emission intensity was increased for some cases, whereas in other cases there were no responses during sudden sharp variations in solar wind plasma speed and density. It has been shown that the presence or absence of the responses in the emissions was not related to the disturbance amplitude of the solar wind parameters. It has been suggested that the emission intensity increase could be caused by the electrons precipitation from the magnetic trap during interaction between the solar wind shock and magnetosphere.