K. A. Shmirko

Effect that jet streams have on the vertical ozone distribution and characteristics of tropopause inversion layer in the far east region

The paper describes a lidar and presents the results of lidar sensing of the vertical ozone distribution (VOD); the lidar measurements are analyzed together with data from a network of meteorological stations situated along the 132° E meridian. VODs over Primorye and Japan in the winter period are compared. An analysis showed that an interrelation exists between the subtropical jet stream and the structures of VOD and tropopause inversion layer. Specifically, the region of the VOD local maximum above the tropopause is in the upper part of the tropopause inversion layer and the width of the maximum depends on the distance from the core of the subtropical jet stream. It is found that the local ozone minimum in the lower stratosphere corresponds to the local minimum of the squared Brunt-Vaisala frequency within this same altitude range in the winter season, when two tropopauses frequently overlap. It is conjectured that the local ozone maximum and tropopause inversion layer may be associated with mixing processes in the layer where stratospheric and tropospheric circulation cells come into contact near the core of the subtropical jet stream.

Spectral characteristics of the femtosecond laser plasma induced on the surface of sea water

Characteristic decay times of continuum and emission doublet intensities (MgII 279.6 and 280.3, CaII 393.4 and 396.8, NaI 589 and 589.6 nm) are presented. Measurements were carried out for plasma induced by a 42-fs laser pulse within a time interval of 0–85 ns. It is shown that the NaI doublet intensity is described by a monoexponential dependence throughout the whole observation time interval. Using the triple recombination coefficient, the electron density has been estimated to vary from 3.0 × 1016 to 2.4 × 1015 cm−3. The validity of the local thermodynamic equilibrium criterion and the dependence of the line intensity-to-background ratio on the delay time are studied.

Results of joint observations of aerosol perturbations of the stratosphere at the CIS-LiNet network in 2008

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).

Results of an integrated aerosol experiment in the continentocean transition zone (primorye and the Sea of Japan). Part 2. Analysis of spatiotemporal variations of aerosol characteristics according to satellite data and lidar measurements

In the paper, we discuss the results of the study of the spatiotemporal aerosol optical depth (AOD) variations in the “continent-ocean” transition zone, performed in spring 2009 in Primorye and in the Sea of Japan with the use of satellite and ground-based AOD measurements. Also, the results of a joint analysis of lidar atmospheric sensing data, back trajectory analysis of air mass transport, and satellite monitoring of the state of the atmosphere of the studied region are given.

Peculiarities of slick formation on the sea surface

This paper deals with surface slicks, their nature, and causes of formation in context of the development of remote detection methods and investigation of dynamic processes in the ocean and at the air–ocean interface. A simplified formalism is introduced for slick–sea surface contrast formation which takes into account the upward sea radiation and qualitatively explains in situ measurement results. The results of a detection of slicks on the coastal water surface are also described, which, together with the simplified formalism suggested, provide optimal experimental conditions for slick–sea surface contrast measurements; i.e., the contrast of the P component of reflected radiation is measured at viewing angles close to the horizon.

Features of development of optical breakdown on an inclined aluminum surface

It is shown that the air breakdown region and the erosion torch during an inclined fall of the laser radiation on the target are separated in time and space—namely, the electron density is higher in the region of the air breakdown, while the concentration of aluminum atoms is higher in the erosion torch. The mechanism of the motion of the laser plasma is determined and the formation time of the erosion torch is evaluated allowing for the film boiling mechanism.

Results of an integrated aerosol experiment in the continent-ocean transition zone (Primorye and the Sea of Japan); Part 1: Variations of atmospheric aerosol optical depth and vertical profiles

We discuss the results of an integrated aerosol experiment, performed in spring 2009 simultaneously in two regions: near Ussuriysk and in the Sea of Japan onboard the Nadezhda training boat. For the measurements of aerosol optical depth (AOD) and moisture content of the atmosphere, we used multiwavelength sun photometers operating in the wavelength range 0.34–2.14 μm. The measurements of the vertical profiles of aerosol characteristics were made using two types of lidars: a lidar based on a three-frequency (1.064, 0.532, and 0.355 μm) Big Sky Laser CFR 200 in Primorye and a one-frequency laser based on the second harmonic of the Nd:YAG (0.532 μm) laser onboard the sailing vessel. It was shown that the springtime atmosphere in the Far East region has two times larger aerosol turbidity in comparison with other (maritime and continental) midlatitude regions. Average values of the atmospheric AOD in the region of 0.5 μm were 0.46 in Primorye and 0.35 in the Sea of Japan. The elevated atmospheric turbidity is caused by continental aerosol of different types (smoke, anthropogenic, and dust) blown off the neighboring regions. We present the characteristic vertical profiles of aerosol-molecular scattering for the cases of advection of air masses from arid regions of Southeastern Asia and the boreal zone of Siberia. A relation is demonstrated between the dust activity in the Taklamakan Desert and light scattering characteristics of aerosol layers in tropopause region.

Specific features of the size distribution of atmospheric aerosol in the continent-ocean transition zone

The distribution functions of atmospheric aerosol obtained on the basis of lidar sounding and photometric measurements over marine water areas in continental and transition zones are analyzed. Changes in the microphysical parameters of the distribution function in the continent-ocean transition zone with height are considered on the basis of data taken from three-frequency lidar sounding. Specific features of changes in the particle size distribution with height during intense dust storms and records of volcanogenic aerosol in the tropopause region in the summer of 2008 are described.

Modeling optical contrast for thin organic films on the sea surface

A continuation of the work dedicated to the study of slicks and film formations on the sea surface is presented. A vector model for the calculation of reflected radiation by the wavy sea surface with respect to the contribution of upwelling radiation from under the sea surface (the second type of waters) is described briefly in [5]. This work contains an analysis of numerical calculations according to the developed procedure and the search for optimal conditions of slick detection. The best conditions for detecting slicks on the sea surface are reached when a P-polarization component of reflected radiation is recorded. In this case, the value of contrast between a slick and a clean surface is 30% higher on average than in recording a contrast without using a polarization filter and is 50% higher than in the case of recording a contrast with a filter oriented to the maximum transmission of S polarization component of reflected radiation. It is shown that, under clear sky conditions, the optimal condition for recording slicks on a sea surface is videotaping in the plane of solar vertical at viewing angles sliding towards the sea surface and when a polarization filter that identifies the Р polarization component of sea radiation is used. In contrast, under overcast sky conditions, it is best to perform observations in the plane that has a wind velocity vector.

Variations in aerosol microphysical parameters of the surface air layer in the “ocean-continent” transitional zone

This article provides the study results of variations in microphysical parameters of atmospheric aerosol in the surface layer of the “ocean-continent” transitional zone. The analyzed data were obtained during the period from August 1, 2010, to December 31, 2012, at the lidar station of the Institute of Automation and Control Processes, Far Eastern Branch, Russian Academy of Sciences (IACP FEB RAS), Vladivostok. Mass concentrations of fine aerosol and black carbon and particle size distribution functions typical for the region under study were obtained. In winter, with strong north winds and low relative humidity (50 ± 20)%, dry continental aerosol predominates, and values of the aerosol number density Na are increased, with maxima in the range from 100 and 120 cm−3. In summer, when south winds prevail and the relative humidity attains 98%, sea aerosol predominates and Na took values from (5 ± 5) cm−3 in June, 2011, to (44 ± 20) cm−3 in July, 2011. Periodicity of diurnal variations in the mass and number density of atmospheric aerosol and black carbon are pronounced the best in winter. The modal radius of fine aerosol particles is from 0.275 μm in summer to 0.375 μm in winter, and of coarse aerosol particles, from 1.05 to 2.5 μm, respectively. Seasonal and diurnal variations in the mass concentration of black carbon MBC are the most stable; its values vary from (0.5 ± 0.5) μg/m3 in the early summer to (3.0 ± 2.0) μg/m3 in January–February. It has been ascertained that diurnal variations in MBC in Siberia (Tomsk) and in the “ocean-continent” transitional zone (Vladivostok) are similar in shape, but the amplitude of variations is higher in the latter case and is maximal in winter.