Proceedings Volume 6936

Fourteenth International Symposium on Atmospheric and Ocean Optics/Atmospheric Physics

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Proceedings Volume 6936

Fourteenth International Symposium on Atmospheric and Ocean Optics/Atmospheric Physics

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Volume Details

Date Published: 6 May 2008
Contents: 4 Sessions, 72 Papers, 0 Presentations
Conference: Fourteenth International Symposium on Atmospheric and Ocean Optics/Atmospheric Physics 2007
Volume Number: 6936

Table of Contents

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Table of Contents

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  • Molecular Spectroscopy and Atmospheric Radiative Processes
  • Optical Radiation Propagation in the Atmosphere and Ocean
  • Optical Investigation of Atmosphere and Ocean
  • Atmosphere Physics
Molecular Spectroscopy and Atmospheric Radiative Processes
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Computer study of ethane absorption by ultra disperse water medium
A. N. Novruzov, O. R. Rakhmanova, A. Y. Galashev
Absorption of ethane molecules by monodisperse water system is investigated by the molecular dynamics method. Stability of (H2O)20 cluster characterizing a system is kept, while the number of captured C2H6 molecules will not exceed four. The capture of ethane molecules by disperse water system results in a decrease in both of the real and imaginary part of dielectric permittivity in the 0 ≤ ω ≤ 1000 cm -1 frequency range. The integral absorption coefficient of IR-radiation increases after absorption of C2H6 molecules by water clusters. The power of thermal radiation of water clusters absorbing ethane molecules decreases. Clusters absorbing two C2H6 molecules have the maximum power of radiation. This cluster has the greatest number of active electrons, interacting with a falling electromagnetic wave.
H2O line shift measurements in the 1.06 u region
Measurements of the pressure shifts coefficients for H2O absorption lines have been performed in the 9403 - 9414 cm-1 spectral region with H2 , O2, Ar, Xe, Kr and air as foreign gases. The data on lines shifts coefficients have been obtained from analysis of the H2O-H2, H2O-O2, H2O-Ar, H2O-Xe H2O-Kr and H2O-Air absorption spectrum recorded at room temperature using Nd glass intracavity laser spectrometer with spectral resolution of 0.03 cm-1 and absorption sensitivity of 10-8 cm-1. The pressure of H2O was varied from 10 Torr to 20 Torr and the pressure of the buffer gases - from 0 to 1000 mbar. The values of the line shifts coefficients for 8 lines have been derived from the recorded spectra, they ranged from 0.009 cm-1/atm to 0.069 cm-1/atm. For each buffer gas a linear relationship of line shifts was measured.
Relaxation parameters of H2O-N2 spectral lines using Pade-Borel transformation
D. S. Emelyanov, V. N. Stroinova
This work is devoted to the investigation of the influence of intramolecular effects on the relaxation parameters of H2O molecule spectral lines in 3ν1+ ν3 band. H2O-N2 halfwidths and lineshifts are calculated in the framework of semiclassical impact theory. Dipole-quadrupole and polarization interactions were taken into account. Calculated H2O-N2 halfwidths and lineshifts are compared with experimental one. The differences between the halfwidths and lineshifts calculated using both traditional Watson hamiltonian and Pade-Borel transformed hamiltonian are analysed.
Application of variational technique to relaxation parameters calculation of highly vibrationally excited CO molecule
A. D. Bykov, V. N. Stroinova, E. L. Smekalina
The model allowed one to calculate the relaxation parameters of highly vibrationally excited diatomic molecules up to dissociation limit is presented. Our model includes the variational technique to compute the wave functions and energy levels and dipole, quadrupole moments, polarizability functions calculated ab initio and/or semiempirically. This paper is dedicated to the calculation of halfwidths and line centre shifts of highly vibrationally excited CO molecule up to the dissociation limit. Semiclassical impact theory is used for calculations. Dipole-dipole, dipole-quadrupole, quadrupole-quadrupole and polarization interactions are taken into account. The necessary matrix elements of dipole, quadrupole moments, polarizability are computed using the variational wave functions. The transition frequencies are calculated using variational technique too. Halfwidths and line centre shifts calculational results are presented as the rotational and vibrational dependences of CO-CO relaxation parameters for the vibrational state v=30.
Halfwidths of H2O-N2 spectral lines of nν2 bands (n=1,...,12)
D. S. Emelyanov, V. N. Stroinova
Spectroscopy of the vibrationally excited water molecule gives the important information to atmospheric physics. In particular, halfwidths of H2O-N2 spectral lines are necessary to compute the contribution of weak lines into the atmospheric absorption function. Earlier H2O-N2 halfwidths for nν2 bands (n=1,...,5) were computed and narrowing effect was found. Probably, this fact is connected with the behaviour of H2O mean dipole moment near the barrier to linearity. This paper is devoted to the investigation of H2O-N2 halfwidths depending on the bending vibrational quantum number ν2. Semiclassical impact theory is used for computations. Intermolecular potential includes the dipole-quadrupole electrostatic term and polarization (induction and dispersion) terms. Mean dipole moments computed in using variational technique are taken into account. Pade-Borel transformation is used to compute line strengths and rotational transition frequencies. Halfwidths calculational results are presented for some lines of nν2 bands (n=1,...,12). The calculated halfwidths are compared with the measured and computed ones and the good agreement is found.
Absorption selectivity influenced on radiative transport in a cloudy atmosphere
The paper has investigated transmission factor, reflectance and absorption factor for the volume of the space limited dispersion medium depended upon optical parameters of the medium and radiation. Investigation was carried out regarding the dependence of the scattering phase function of radiation upon the absorption wave-length and the line form. Finally, results have been compared with data theoretically obtained from the radiative transport and based on the assumption that radiation does not depend on the wave-length (within the spectral line) and space unlimited dispersion medium.
Formation of radiation balance in a cloudy atmosphere
The paper is dealt with the laws of radiative transport within space limited scattering mediums depending on optical dimensions of a cloud and its micro physical properties. Detected was the range of application for infinitely extended dispersion medium and meanings of optical thicknesses at which the medium can be regarded as unlimited. In accordance with these results the authors conclude the nebulosity influences the radiation balance of the atmosphere depending on the cloud distribution according to their optical dimensions.
Dipole moment functions of X2-Y and X2-Y2 dimers
Mikhail A. Buldakov, Victor N. Cherepanov, Yuliya N. Kalugina
The method to calculate the dipole moment of X2-Y and X2-Y2 dimers as a function of their geometrical parameters is proposed. This method allows taking the internuclear distance in X2 (Y2) molecule into account. Analytical expressions for the dipole moment surface of the complexes are suggested. The method is applied for the calculation of the dipole moment surface of N2-Y (Y = He, Ne, Ar, Kr) and N2-N2 dimers.
Use of Cartesian coordinates in molecular spectroscopy of atmospheric gases
Anatoli S. Makhniov
On the basis of the analysis of influence of isotope substitution on system of the electronic and nuclear equations for any molecular system conditions of invariance are formulated relatively to the isotope substitution surfaces of the potential energy expressed in the Cartesian coordinates. Except for that it is shown, that this property of potential function is the consequence of the appropriate property of this function expressed in curvilinear internal coordinates, that, in its turn, allows at theoretical research of vibration - rotation spectra of isotope substituted molecules, and also at the solution of a direct and the inverse anharmonic problems to avoid the use of curvilinear internal coordinates, having replaced them by Cartesian. Expressions for classical and quantum-mechanical Hamiltonians of normal molecule in Cartesian coordinates are obtained.
Fine structure of the water refractive index in the range of 1.06 um: experiment and theory
V. V. Nosov
The paper describes theoretical and experimental data for fine structure of substantial water refractive index in the range of 1.06 μm (9400-9420 cm-1). Theoretical results were calculated in the framework of the Lorentz-Lorentz spectroscopy with the use of theoretical and experimental data for the absorption coefficient as well as the Kramers-Kronig formulae. Experimental results were obtained using the original processing of data of the known measurements of water vapor absorption in the range of 1.06 μm (the data of Fulghum and Tilleman). The fine structure of the water refractive index was registered experimentally. It has been found that the obtained theoretical results agree very closely with experimental data.
Optical Radiation Propagation in the Atmosphere and Ocean
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Incoherent sinusoidal-Gaussian and annular beam scintillations
The scintillation index is evaluated in horizontal turbulent atmospheric optical links for incidences of incoherent cosh-Gaussian (IChG), cos-Gaussian (ICG) and annular (IA) beams. Weak turbulence solution is obtained for a slow detector. Dependence of the intensity fluctuations of the IChG, ICG and IA beams on the link length, source size, wavelength and the structure constant are examined. At all the link lengths, fixed size IChG and ICG beams exhibit lower scintillations for larger absolute displacement parameters. At a fixed link length, IChG beam yields lower fluctuations than the ICG beam having the same absolute displacement parameter. For the same size primary beams, IA beam with narrower ring scintillates less than the IA beam with wider ring, and this holds to be valid for each link length. Investigation of the scintillation versus the source size reveals that increase in the source size lowers the scintillations for all types of the incoherent beams. At the same source size and the same absolute displacement parameter, IChG beams have lower fluctuations than the ICG beams, larger absolute displacement parameters exhibiting lower scintillations at the same source size for both beams. For IA beams, as the size of the primary beam is increased, the scintillations are reduced for all ring sizes, the reduction being pronounced for narrower rings. As the wavelength increases, the scintillations of IChG and ICG beams first increase, then at around the wavelength forming the Fresnel zone, the scintillations start to decrease and eventually for all types of IChG and ICG beams, the scintillation indices merge towards a certain value. Similar behaviour of the scintillations versus the wavelength is observed for IA beams as well. As long as the structure constant is kept within the range of interest to remain in the weak turbulence, raising the structure constant first increases the intensity fluctuations of beams for all the mentioned beam types where further rises in the structure constant result in the same level of scintillation index. Comparison of the scintillations of IChG, ICG and IA beams with their coherent counterparts and the coherent Gaussian beam shows that the IChG, ICG and IA beams are favorable for large sized sources.
Relative molecular diffusion and tracers' localization in 1D channel
E. Z. Gribova, A. I. Saichev
For particles of the passive floating admixture initially located in the same physically infinitesimal volume in incompressible flow the features of clot's density behavior are discussed. For analyses of density evolution we study both analytically and numerically the motion of admixture in the random velocity field taking molecular collisions into account. Using the one-dimensional model, we analyze the closely related effects of relative molecular diffusion and fluctuations of density of particles. One can show that in the beginning admixture is in the Brownian motion mainly and then an influence of turbulence becomes more considerable. It is found that because of asymmetry of chaotic compression and tension the clot of particles compresses more often than stretches. As a result the effect of localization of particles takes place in spite of molecular diffusion strives for scattering particles far away. This effect may explain in particular processes of clouds formation or localization of oil spots on ocean surface.
Frequency-pulsed regime of excitation of spherical microcavity by chirp ultra-short laser radiation
D. V. Apeksimov, Yu. E. Geints, A. A. Zemlyanov
The numerical simulations results of resonance excitation of internal optical field of transparent spherical microparticles under irradiation by ultra-short laser pulse train are presented. It was determined that the most optimal tuning of incident radiation to assigned high-Q eigenresonance of a particle might be realized using varying a porousness of pulse in a train with linear frequency modulation of each pulse in a train (chirping). Analytical expressions were found for calculation of these parameters depending on laser pulse duration and frequency location of excited resonance.
Measurement of turbulence parameters and wind speed on basis of differential method
L. V. Antoshkin, N. N. Botygina, O. N. Emaleev, et al.
It is presented the differential method of the measurement of turbulence parameters. This method was tested by differential optical monitor of turbulence parameters. In this paper the differential method is applying in the action of the wave front sensor. From monitoring of the dispersion of the difference between the shifts of the power centers of the gravity of the focal spots are calculating the structural constant of the refractive index Cn2 and the cross forming of the wind speed.
Frequency dependencies of the skin-layer and surface impedance by the fractal of medium
V. K. Balkhanov, Yu. B. Bashkuev, M. G. Dembelov
Results of modelling the fractal by geometry of a skin-layer HS and the module of a surface impedance |δ| of a geoelectric cut of item of measurement "Lake" are considered. Frequency dependences of a skin-layer HS and the module of a surface impedance |δ| become sedate: HS ~ f -D, and |δ| ~ f 1-D, where f- frequency. In a range of 1 Hz - 1 MHz the following is received: HS ~ f -0.48, and |δ| ~ f 0.53. Results mean, that spending sites of considered item of measurement form Cantor set with dimension the fractal D = 0.47 ± 0.01.
Acoustic experimental investigation of interaction femtosecond laser pulses with gas–aerosol media and biological tissues
N. N. Bochkarev, A. M. Kabanov, A. N. Stepanov
Using two optical acoustic approaches we experimentally investigated spatial location of filament zone of propagation channel of focused laser radiation. For femtosecond pulses passing in air it was shown that nonlinear focus length had spatial scale of 1/P at initial power P moderate for self-focusing and at optical system focus distance significantly lower than Rayleigh beam length. The results of experimental optical acoustic investigation of femto- and nanosecond pulses attenuation by some biological tissues (muscular tissue, adipose tissue, cutaneous covering, milk) and optical breakdown thresholds on these one are presented. It was shown that penetration depth of short laser pulse radiation into biological tissues is the same as for longer one. However, amplitude of acoustic response to a process of interaction of femtosecond laser pulse with biological tissue is larger in several times than that to interaction with nanosecond pulses of the same power and spectral distribution. The obtained of threshold values can be interesting for tabulation of limit allowable levels of irradiation at work with laser radiation. Such values are unknown for femtosecond laser pulses today.
Invariance of the Navier-Stokes and Maxwell's equations under the laws of geometrical similarity
V. K. Balkhanov
On the basis of laws of mechanical similarity Kolmogorov's hypothesis about invariant dispersion is proved to energy at turbulent current of a liquid. Laws of similarity are widespread to electromagnetic processes. Communication of the critical parameters responsible for percolation processes, with dimension the fractal of medium is established.
Laser guide stars and models of atmospheric turbulence
We propose a modified approach to form a laser guide star (LGS) with a wide, collimated laser beam launched through the full aperture of a telescope. Using a special form of field stop (diaphragm) uniquely positioned for each subapertures, the wavefront sensor "sees" only a small part of the source corresponding to the area on the sky, which is cut out by the field stop. Each of these spherical waves subtends the area of a separate subaperture at the telescope pupil. Thus, the LGS is formed of a set of spherical waves. Since the linear size of the subaperture is approximately equal to the coherence radius, the measured wavefront can be restored as a smooth phase function. In the paper use of this scheme is investigated. It is well know that adaptive optical system (AOS) operating on astronomical telescopes with a LGS has limitations due to the effect of the focal anisoplanatism, since the spherical wavefront that comes from the LGS does not pass trough the same portion of turbulence atmosphere as plane wavefront of natural guide stars (NGS) located at an infinite distance from ground. There have been proposed several different approaches to overcome the focal anisoplanatism. In the method proposed by Buscher et al, sensing of the turbulence-induced wavefront distortions is performed on the outgoing path of a collimated laser beam by forming an extended intensity pattern in the atmosphere and analyzing its distortion from the ground. In a recent work, the prospect of using a collimated laser beam launched through the main telescope has been revisited and a special wavefront sensing scheme has been proposed. In the present paper we show possible implementation for this scheme and give analytical analysis of AOS performance.
Detectable distance determination of light-signal complexes
V. P. Budak, G. A. Kaloshin, K. S. Sokolov, et al.
In this paper the mathematical model of the visibility range determination of a laser beacon in a navigational complex is offered. The model includes model of the optical properties of a coastal atmospheric haze, algorithm of the light field calculation in a turbid medium and the statistical model of the image perception by the given level of detection probability. Calculation of laser signal atmospheric attenuation is conducted with use small angle approximation method of spherical harmonics.
The polarization state spatial distribution of atmosphere-scattered radiation obtained by complete analytical solution for the vectorial transport equation
V. P. Budak, S. V. Korkin
The paper deals with the polarized radiative transfer within a slab irradiated by a collimated infinity-wide beam of arbitrary polarized light. The efficiency of the proposed analytical solution lies in the assumption that the complete vectorial radiative transfer solution is the superposition of the most anisotropic and a smooth parts, computed separately. The vectorial small angle modification of the spherical harmonics method is used to evaluate the anisotropic part and the vectorial discrete ordinates method is used to obtain the smooth one. The azimuthal expansion is used in order to describe the light field spatial distribution for the case of abnormal irradiance and to obtain some known neutral points in the sky especially useful for polarized remote sensing of the atmosphere.
Two-photon induced fluorescence of organic molecules in microcavity
The problem about two-photon induced fluorescence of organic dye active molecules located in spherical transparent microparticles at the ultrashort laser pulses influence was theoretically investigated. The system of kinetic equations for laser generation was written taking into account stimulation transitions. Generation regimes of stimulated radiation were found. Resonator properties of spherical microparticles were theoretically investigated using the method of expanding optical fields into series of eigenfunctions. The breakdown of the beginning of stimulated radiation in the microparticle was determined. It was shown that stimulated radiation intensity depends on degree of its spatial overlap with all other modes of the pump radiation. The interpretation of experimental data of two-photon induced fluorescence in the particles with organic dye was carried out.
Reflection from the rough surface at glancing angles
Pavel N. Dagurov, Aleksey V. Dmitriev, Tumen N. Chimitdorzhiev
New approach to the calculation of reflection from the rough surface by means of Kirchhoff's method at glancing angle is presented. It is shown that value of reflected coherent field at glancing propagation depends on the size of the surface roughness.
Determination of cloud base height using the passive monostatic method
S. V. Zuev, N. P. Krasnenko
Among passive methods for a cloud base height (CBH) detection, bistatic and monostatic methods are known. In the first case a triangulation method with two photodetectors is used. A drawback of this method is a need in obtaining images of the one overcast fragment by two spatially separated cameras in the course of shot time. In consequence, images have different view angles and the problem of identification of this fragment appears. The passive monostatic method for CBH detection does not have these demerits. For measurement by this method, linear sizes of object should be known. But for a case of CBH detection it is impossible, because cloudiness can change in the course of short time. The offered method does not demand knowledge about linear sizes of cloudiness fragments. The method uses dependence of scale change of object image at change of focal length of camera lens depending on distance up to object.
Monitoring peculiarities of turbulence parameters on basis of differential method
L. V. Antoshkin, V. V. Lavrinov, L. N. Lavrinova, et al.
It is presented a numerical model of the wave front sensor. In this investigation a wave front senor was applying also for calculating of the turbulence parameters on basis differential method. It are determined the peculiarities of modeling of a dynamic turbulence for the using of the differential method in monitoring of the turbulence parameters.
Astroclimate of specialized stations of the Large Solar Vacuum Telescope: Part I
V. V. Nosov, V. M. Grigoriev, P. G. Kovadlo, et al.
The paper presents the results of measurements of characteristics of local astroclimate in special production areas of the Large solar vacuum telescope (the Baikal astrophysical observatory of the Institute of Solar-Terrestrial Physics SB RAS). It is demonstrated that the temperature gradients in the telescope rooms are the cause of the initiation of the Benard cell and originating (incipient) turbulence in the pavilion of the astronomical spectrograph. The characteristics of the originating turbulence were studied in detail. It has been found that the measurements date have supported the basic scenarios of stochastization (Landau-Hopf, Ruelle-Takens, Feigenbaum, Pomeau-Menneville scenarios). The Feigenbaum bifurcation diagram has experimentally been supported. It is shown that the basic vortex in Benard cell breaks down into smaller vortices as the result of ten bifurcations of the period duplication. It has been found that the originating turbulence introduced large errors in the data of spectral measurements, even at the path of small length. The horizontal random displacements of spectral lines, appearing due to the pavilion effects, in the horizontal Ebert scheme can reach 1 second of arc. In this case the line displacements occur slowly, at the frequency about 0.01 Hz. Because of low frequencies of line displacements the originating turbulence by its optical characteristics approximated the regular refraction.
Astroclimate of specialized stations of the Large Solar Vacuum Telescope: Part II
V. V. Nosov, V. M. Grigoriev, P. G. Kovadlo, et al.
The paper presents the results of measurements of characteristics of local astroclimate in special production areas of the Large solar vacuum telescope (the Baikal astrophysical observatory of the Institute of Solar-Terrestrial Physics SB RAS). It is demonstrated that the temperature gradients in the telescope rooms are the cause of the initiation of the Benard cell and originating (incipient) turbulence in the pavilion of the astronomical spectrograph. The characteristics of the originating turbulence were studied in detail. It has been found that the measurements date have supported the basic scenarios of stochastization (Landau-Hopf, Ruelle-Takens, Feigenbaum, Pomeau-Menneville scenarios). The Feigenbaum bifurcation diagram has experimentally been supported. It is shown that the basic vortex in Benard cell breaks down into smaller vortices as the result of ten bifurcations of the period duplication. It has been found that the originating turbulence introduced large errors in the data of spectral measurements, even at the path of small length. The horizontal random displacements of spectral lines, appearing due to the pavilion effects, in the horizontal Ebert scheme can reach 1 second of arc. In this case the line displacements occur slowly, at the frequency about 0.01 Hz. Because of low frequencies of line displacements the originating turbulence by its optical characteristics approximated the regular refraction.
Multiphoton excitation of fluorescence in spherical particles: angular distribution of scattered radiation
Alexander A. Zemlyanov, Yuri E. Geints, Ekaterina K. Panina
The angular distribution of spontaneous fluorescence excited inside a spherical microparticle by femtosecond laser radiation is considered. The distribution of the internal optical field of a particle is investigated at the multiphoton excitation of fluorescence. The position and the effective volume of fluorescence sources in a particle are calculated numerically as functions of the particle radius in the cases of one-, two-, and three-photon excited fluorescence. The equation determining the relation between the mean brightness of fluorescence from the front and rear hemispheres of a particle is derived within the framework of geometric optics. It is shown that if a fluorescence source is located near the shadow hemisphere of a particle, asymmetry appears in the angular distribution of spontaneous fluorescence in the forward and backward directions. This asymmetry becomes more pronounced, as the number of photons taking part in the process increases.
Earth's atmosphere distorting influence when observing Sun oscillatory-wave processes
Sergey A. Chupin, Nikolai I. Kobanov
When carrying out optical observations of the sun using ground-based instruments, the main cause of error is the Earth's atmosphere. Daytime seeing will be best on two conditions: low gradients in the parameters of the Earth's atmosphere along the line-of-sight and high transparency (negligible stray light). Telluric line shifts caused by atmospheric instabilities were studied. Besides that, the influence of such parameters as atmospheric pressure and aerosol concentrations on daytime seeing were examined. Seeing was determined using a spectrogram. Analysis of the Fourier spectra of telluric line shifts revealed that seeing is mainly influenced by high-frequency turbulence in the Earth's atmosphere in the 0.1-4 Hz range (0.25-10 sec period). Study of the dependence of the stability of the Earth's atmosphere on aerosol concentration and pressure showed that the influence of aerosols was more expressed than that of pressure. It would appear that aerosols promote flattening of temperature gradients in the Earth's atmosphere and in this way improve conditions for solar observations.
The account of polarizable singularities of diffractional field in VHF range
V. N. Abarykov, A. S. Batoroev
On the basis of confrontation of account results of diffractional attenuation on absorptive and impedance sample models of a convex obstacle the model of the count of a complementary field reduction of vertical polarisation on diffraction radio paths with woody tops mountain obstacle is offered. This model well explains the experimental results.
Amplitude-phase ray in a randomly inhomogeneous medium
V. V. Nosov
Nonlinear equation of amplitude-phase optical wave fluctuations in a randomly inhomogeneous medium is considered. The solution of the set of equations is obtained from integration along the vector characterization. In a small-angle approximation, the vector characterization is a normal to the phase front, therefore, it is called amplitude-phase ray (or ray, only). A nonlinear integral-differential equation is obtained for the average amplitude-phase ray in a turbulent-medium propagating Gaussian optical beam. It is shown that the average amplitude-phase ray agrees with the paraxial approximation for the average diffraction ray.
Optical Investigation of Atmosphere and Ocean
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PHOTONS/AERONET sunphotometer network overview: description, activities, results
P. Goloub, Z. Li, O. Dubovik, et al.
PHOTONS is the french component of the AERONET sun-photometer network which provides globally distributed near-real-time observations of aerosol spectral optical depth and sky radiance as well as derived parameters such as particle size distributions, single-scattering albedo and complex refractive index. Now more than 12 years of worldwide distributed data from the network of ground-based radiometers are available. These data are best suited to reliably and continuously derive the detailed aerosol optical properties in key locations. Mid 2007, about 40 sites mainly located in France, Europe, Africa as well as in Asia are managed by PHOTONS. Since 2001, the network also contributes to passive/active sensors synergies. Several sites in France, western as well as eastern Europe, sometimes in connection with EARLINET, are equipped with both lidar system and sun-photometer dedicated to aerosol and cloud observations. These synergies will be enhanced in the future mainly within the context of A-Train experience. In this paper, we provide a general description of PHOTONS network activities and facilities, and present recent results both on instrumental side (development on new sun-photometer, vicarious calibration methods), on scientific side (A-Train mission validation like aerosol retrieval algorithms of PARASOL) and aerosols retrieval from ground-based measurements method.
Statistical and spectral analysis of the rhythmic structure of pressure signals under exercise stress
L. N. Azargaev, V. V. Boronoyev, L. V. Kosygina, et al.
This paper shows the results of the tests on the heart rate variability under exercise stress registered and processed by the Automated Pulse Diagnostic System (APDS).
Determination of CO concentration using the modified laser correlation method
Waldemar Wójcik, Andrzej Kotyra, Paweł Komada, et al.
In the paper, the modified correlation method is presented as well as results of CO concentration measurements in laboratory conditions using this method. Measurements were obtained for high CO concentrations (exceeding 50%) and short optical path (1 and 2m long). The measurements can be treated as a reference for measurements for far low concentrations and longer optical paths. Some simulation results also has been presented showing influence of temperature and pressure on measurement accuracy.
The cloudiness parameters recovery from optical remote sensing data
V. P. Budak, O. P. Melamed
Remote sensing inverse problem solution is carry out in independent pixel approximation (IPA) assumption on the base of the radiative reflection from turbid media slab with arbitrary phase function and Lambertian surface numerical model.
Particularities of circulation and the analysis of dust storm in sharp continental climate conditions of Mongolia
Ayuna L. Dementeva, Galina S. Zhamsueva, Alexander S. Zayahanov, et al.
In given article results of experimental researches of meteorological parameters in atmosphere of arid and semiarid territories of Mongolia received during scientific expedition 2006 are resulted. Meteorological fond data 2003-2005 of st. Sainshand and st. Baruun-Urt for the analysis of dust storms conditions and ways of distant transport small gaseous impurities in atmosphere of desert Gobi are analyzed.
Automated data processing and acquisition system for experimental physical mounts
G. E. Kulikov
In the present paper the structure of data processing and acquisition system for experimental physical mounts is proposed. The structure of the offered system is invariant relatively conditions of the experiment. The system may be realized as single-host system, or as distributed system. The problem of correctly sharing of the computational resources between the time-consuming subroutines is solved by using of a multithread model. The present work may be used as a building basis of various data processing and acquisition systems for widely range of experimental physical units due to using of rigorously hierarchical, device-independent construction of the system and by using a simple abstract data acquisition model. The system provides long-term observations, necessary for geophysical research.
The features of continuous wavelet transform for physiological pressure signal
V. V. Boronoyev, B. Z. Garmaev, I. V. Lebedintseva
The paper shows the possibility of continuous wavelet transform application for the analysis of pulse model signals. It has been found that wavelet analysis is capable of defining local characteristics of a signal and investigating any changes in the spectral distribution of a pulse signal. The wavelet spectra of pulse signals of healthy people and of people with functional disorders have been investigated. It has been shown that the shape of pulse signals of people with functional disorders is changing, which brings about change in the wavelet spectra. The paper describes a new wavelet-based detection method for physiologic pressure signal components.
Lidar measurements for the short-term forecast of meterorological stability
Yury Polkanov, A. K. Zhdanovichy
It is proposed to predict a reduction of the meteorological situation stability, as more inertial process, from an anticipatory change of the revealed structure character of optical inhomogeneities of a ground layer concerning a steady atmosphere. It opens up possibilities to use in forecast the method of optical anomalies detection which occurrence is caused by powerful local breaking of the atmosphere thermodynamic stability non-connected with the daily meteorological situation. They can be caused by sharp atmospheric processes of spontaneous-catastrophic character as well as man-caused disasters outside of the measurement zone when a possibility to predict a mechanical trajectory of such a distortion on the basis of similar predictors becomes a vital importance.
Medium sensing by low-power strobe pulse
Yury Polkanov, A. K. Zhdanovichy
At the present time laser systems for atmospheric remote sensing assume the use of powerful pulse lasers in most cases and a signal backscattered from a medium is recorded with a certain step digitization corresponding to the required spatial resolution. Moreover a distance extension of sounding requires essentially disproportionate increase in radiation power and use of complex methods to extend a dynamic range of receiving devices; it also causes the multiple scattering effects which can be difficult to take into account. Qualitatively new approach which allows many by-effects to be avoided is proposed. The approach is based on use of a low-power radiation source (for example, white light) with specified gating, when time of source radiation interruption is equal to a pulse duration of an ordinary lidar (about 10-8 c), and frequency corresponds to a propagation time of radiation in a zone where the multiple scattering can be neglected. Digitization of the recorded backscattered signal can produce by ordinary digital systems as a discrete readout of signals with the same duration. However to increase a reconstruction accuracy for the medium characteristics we propose to reconstruct the average values of these characteristics over the parts commensurable with the sounding path length. The algorithm proposes creation of recording system with corresponding gating for incoming signal. Estimations1 have shown that the measurements with accuracy of ~ 1...10 % become possible in the single scattering over the wide range of atmospheric conditions and for safety source power up to 10-20 watt. Moreover, a linear operating mode for photoelectric multiplier can be easily provided and measurements can be carried out in the daytime with the specified accuracy. Such an approach allows us to increase a precision of measurements and can be applied in various areas from the lidar and radar systems to biological and medical devices.
Lensless methods to transform small angular displacement of a laser beam into circular scanning and to receive radiation by the small-sized device within the limits of a spatial hemisphere
Yury Polkanov, A. K. Zhdanovichy
Presented radiating device transforms an angular displacement of a laser beam in limits of several degrees into circular movement on forming a cone which axis coincides with an optical axis of an emitter. Speed of such circular scanning does not depend on a corner of a scanning cone, and is determined by time mentioned small (within the limits of several degrees) linear moving of a laser beam with the help of standard methods. The suggested device basis is represented with a simple optical element with small losses of transformation on reflection. The reception device having a similar reception element provides gathering radiation from a wide spatial zone (close to a hemisphere), with proportional dependence of intensity of a registered signal on a corner of falling of a corresponding light beam, for example scattering back certain object of laser radiation. The radiation falling from a determined direction will be transformed to a corresponding ring zone on the receiver. Proceeding from position of a scanning beam and a ring zone on the receiver which direction reflected signal and distance up to a source of reflection is defined has come. The given devices can find application in compact systems of scanning for a wide range of systems of ecology, cartography, high technologies, medicine and biology. Absence of complex optical elements allows to avoid expensive manufacturing techniques, inaccessibility of direct influence on a working zone allows to provide high reliability of functioning of system.
Robust criteria
The problem of testing the hypothesis H0: θ = θ0 against the alternative hypothesis H1l0+▵(√N)-1 is examined for the Shurygin noise model, where θ =T(Fθ) is an unknown parameter. In the present report, a class of criteria robust in the sense of the significance value and power density function is considered for parametric and nonparametric problem formulation on statistics of the form SN=√N((θN-θ)/(√V(θN))), where V(θN) is the θN variance and θN =T(FN) is the robust parametric or nonparametric estimate of the parameter θ =T(Fθ) obtained by the weighted maximum likelihood method.
Possibility of supervision over detailed structure of ocean currents by MODIS
V. E. Sklyarov
The report focuses on the analysis of the detail structure of ocean currents in areas of dust storms distribution or intensive phytoplankton's development. Dust storms represent the global phenomenon occurring regularly and, thus, atmospheric streams transfer a significant amount of the sand and dust (more than 2000 million tons) from deserts of Gobi, Sahara, Namibia, and Arabian Peninsula etc. The dust from Sahara achieves Caribbean Sea and southeast areas of USA for 5-7 days, and traces of the Asian dust storm, which have crossed Pacific Ocean, were found out in Great Lakes. For the purposes of our research the influence of sand and a dust dropping out from atmosphere on optical properties of the top layer of the ocean is represented especially significant. We shall note, that this question is poorly covered in the scientific literature. On our data, there are only separate certificates that return dispersion in green area of a spectrum for the top layer of the ocean is considerably increased after passage of a dust storm. It occurs due to saturation of the ocean top layer sand particles were sunlight diffusion is good. On the other hand, these particles, being a passive tracer, are easily involved by separate jets of currents in local circulation. These factors create a real basis for space observations on details mesoscale ocean circulation. As a trial experiment, author of the report have leaded the multispectral analysis data from MODIS (satellite AQUA), received on a northwest part Indian Ocean and Gulf of Aden. Results of the analysis confirm the made hypothesis.
Seasonal dynamics of the physical characteristics of the atmosphere aerosol layers in transitional ocean-continent zone near the city of Vladivostok during 2006-2007
O. A. Bukin, A. N. Pavlov, K. A. Shmirko, et al.
Aerosol layers stratification in transitional ocean-continent zone are presented. Seasonal dynamics of aerosol optical thickness is shown. Aerosol dust impact on the phytoplankton community's state estimated.
Atmosphere Physics
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Dynamic-stochastic method of modelling of climate of the atmosphere
A. V. Protasov
A dynamic-stochastic method of modeling of climatic ensembles of fields of meteorological elements is considered The results of numerical experiments on application of climatic ensembles for research of properties of an atmosphere dynamics are presented.
Mesoscale modeling of thermal circulation forced by airflow and urban heat island
A. F. Kurbatskiy, L. I. Kurbatskaya
The modified three-parameter model of turbulence for a thermally stratified atmospheric boundary layer (ABL) is developed. The model is based on tensor-invariant parameterizations for the pressure-strain and pressure-temperature correlations that are more complete than the parameterizations used in the Mellor-Yamada model. The turbulent momentum and heat fluxes are calculated with explicit algebraic models obtained with the aid of symbol algebra from the transport equations for momentum and heat fluxes in the approximation of weakly equilibrium turbulence. The three-parameter model of thermally stratified turbulence is employed to obtain closed form algebraic expressions for the fluxes. The effects of urban roughness are parameterized. Results of 2D computational test of a 24-hour of the ABL evolution are presented. Comparison of the computed results with the available observational data and other numerical models shows that the proposed model is able to reproduce both the most important structural features of the turbulence in an urban canopy layer near the urbanized PBL surface and the effect of urban roughness on a global structure of the fields of wind and temperature over a city.
A response of the mid-latitude ionosphere to propagation of the atmospheric gravity wave
E. L. Afraimovich, A. F. Yakovets, V. V. Vodyannikov, et al.
This study reports observations of the response of the mid-latitude ionospheric F-layer to the passage of the atmospheric gravity wave (AGW) produced by the July 2004 geomagnetic storm, using data from the ground ionosonde located at Alma-Ata (43.25°N, 76.92°E). Ionograms were recorded every 5 min. They were analysed for temporal variations of virtual heights of specific frequencies (the virtual heights of a constant electron density), critical frequencies of the F-layer (fo,xF) and height profiles of the electron density (N(h)-profiles). The temporal behaviour of all F-layer parameters such as the altitude of its peak (hmF), the electron density at the peak (NmF) and the half thickness of the layer (ΔhF) revealed well-defined wave structures throughout the entire night of 24-25 July 2004. A comprehensive understanding of the relationship between phases of various parameters of the F-layer is established. It is shown that the relationship between phases of hmF, NmF and ΔhF variations is determined by the value of the wave front tilt. As a rule, the certain phase of ΔhF precedes that of hmF, and NmF anticorrelates with ΔhF. Last result contrast with previous investigations, which have frequently assumed a negative correlation between NmF and hmF. A small amplitude of NmF variations compared with N(t) at certain altitudes may be largely explained in terms of the height gradient of AGW amplitudes.
Influence of the Earth's diurnal rotation on the propagation of large-scale disturbances in the upper atmosphere
Nataly P. Perevalova, Edward L. Afraimovich, Sergey V. Voeykov, et al.
Influence of the Earth's diurnal rotation on dynamic parameters of large-scale disturbance of Total Electron Content (TEC) was investigated. For this purpose TEC data from the international GPS network were used. We have examined TEC disturbance generated in the northern hemisphere during strong magnetic storm on October 29, 2003. This disturbance is characterized as a large-scale wave of a solitary type with the annular front shape whose center is located near the geomagnetic pole. It was shown that the velocity and travel direction of the disturbance had a strongly pronounced longitudinal dependence. The least velocity (700 m/s) was detected in the night hemisphere, where TEC value was minimum. The greatest velocity (1600 m/s) was detected in the day hemisphere, where TEC value was maximum. In general the disturbance traveled equatorward. But we found out "swirling" effect of disturbance travel in the direction opposite to the Earth's rotation. The zonal projection of the disturbance velocity directed westward causes this "swirling" effect. In the morning and evening sectors the zonal projection was exceeded the meridional one. In the night and day sectors disturbance traveled in the meridional direction nearly. Comparison with the Global Ionospheric Maps (GIM) data showed that zonal transfer of disturbance is probably caused by the movement of the ionization maximum due to the Earth's diurnal rotation.
Variations of 557.7 nm and 630 nm atmospheric emissions in the 23rd solar cycle
Alexander V. Mikhalev, Irina V. Medvedeva, Nadezhda V. Kostyleva, et al.
We present preliminary analysis of experimental data of the nightglow observation of the atomic oxygen 557.7 nm (emitting layer height is 85-115 km) and 630 nm (180-250 km) lines emissions in the 23-rd solar cycle. The experimental data were obtained at ISTP Geophysical observatory near Irkutsk (52° N, 103° E). The 557.7 nm and 630 nm emissions observational data are compared with atmospheric, solar and geophysical parameters. Generally, the 630 nm emission intensity in the 23-rd solar cycle changed in a phase with the solar cycle, increasing from the period of low solar activity to the period of high solar activity. The difference of correlation coefficient between green line intensity and F10.7 solar radio flux in various phases of the 23-rd solar cycle was marked. During the increasing and maximum phases of the solar cycle the negative correlation between monthly mean values of the 557.7 nm emission intensity and the F10.7 was revealed. The correlation became positive during the descending phase. Broken phase synchronism of 557.7 nm emission behavior and F10.7 during the growth and maximum phase of the 23-rd solar cycle is preliminary interpreted by high sensitivity of the atmospheric parameters determining 557.7 nm emission intensity to atmospheric dynamics and various disturbances including the effects from lower atmospheric layers.
Density gradients at evening ionospheric troughs in the East sector
Olga M. Pirog, Nelly M. Polekh, Anatoly V. Tashchilin, et al.
Abrupt decreases of ionization in the F2-layer maximum in afternoon hours have long been observed and associated with a motion of the main ionospheric trough to the equator during geomagnetic storms. A sudden increase of electron density followed by its fall is at times observed in afternoon and evening hours. This phenomenon, well-known as the "dusk" effect, appears during strong storms which commence in early evening hours LT at stations located at subauroral and middle latitudes. An explanation for abrupt decreases of critical frequencies of F2 layer in afternoon and evening hours can be the effect of plasma fast convection in a westward direction caused by intense electric fields. The results of the simultaneous satellite and ground measurements of the effects of fast subauroral ion drifts show that the development of a narrow band of a westward drift with high velocities causes the intensive depletion of electron density in the F2 layer for 15-20 min. This is consistent with the fast formation or deepening of the trough in the background ionization. The purpose of this paper is to investigate peculiarities of this phenomenon in the East-Asian region. Ionospheric storms with different intensities are examined based on the data of the meridional chain of ionospheric stations located in the region of East Siberia and China. It has been determined that afternoon troughs can be observed either during the growth and main phases of strong and moderate storms if their commencements fall on evening hours or during the recovery phase if they begin some other time. They are mainly observed in the period between equinox and summer. Model calculations of electron density variations during the storm on April 3-6, 2004 are carried out. It is shown that the location of minimum and polar wall of afternoon trough coincides with the band of the westward drift in the time sector 13÷17 MLT at geomagnetic latitudes 55° ÷ 65°.
Manifestation of large geomagnetic storms in ionosphere of East Asia
E. B. Romanova, A. V. Tashchilin, O. M. Pirog, et al.
The ionospheric response to a geomagnetic disturbance is a complex set of events caused by both the upper atmosphere and ionosphere parameters and characteristics of the magnetosphere and solar wind. A situation is particularly complicated during the large geomagnetic storm. We present the results derived from investigating of the ionospheric response to large geomagnetic storms with the values of index Dst < (-200 ÷ -300nT) observed during two last cycles of solar activity. Our analysis of the behavior of the ionosphere is based on using the measurements from a network of ionospheric stations located at different latitudes in the longitudinal sector of 60-150°E. Also there are presented the results of numerical modeling of ionospheric parameters during the geomagnetic storm on April, 2000δ which show a good agreement of calculations and measurements. As the results modeling illustrates prolonged negative ionospheric disturbances observed during geomagnetic storms may be produced by the change of thermosphere composition.
Total electron content variations during the strong typhoon 5-11 August 2006 near southeastern coast of China
S. V. Voeykov, A. B. Ishin, N. P. Perevalova
The analysis of total electron content (TEC) variations as deduced from GPS data of 11 sites in the region (5°S-80°N; 110-160°E) during 2-15 August 2006 was carried out to find possible ionospheric effects of the strong typhoon SAOMAI (5-11 August 2006) near south-eastern coast of China. For this purpose we used also Global Ionospheric Maps (GIM). The intensification of TEC variations in the time period range 32-128 min for evening local time was found in the region of the typhoon activity during magnetic storm of August 7, 2006. However this effect more likely was caused by dynamics of the equatorial anomaly irregularities as well as by disturbed geomagnetic situation (Kp was up to 5-6, Dst varied from -74 to -153 nT). The analysis of absolute TEC diurnal variations and TEC variations in the time period range 2-25 min didn't show evident change of spectrum of TEC variations during typhoon in comparison with neighbor days. Therefore we didn't find ionospheric disturbances that were caused by typhoon SAOMAI. Perhaps the ionospheric typhoon effects were too weak to be picked out from background ionospheric variations using TEC measurements.
Results of natural objects research by methods of ultra-wide band location
D. D. Darizhapov, B. Ch. Dorjiev, O. N. Ochirov, et al.
For ultra-wide band (UWB) of a radar-location by most important meaning is the correlation of used signals with a frequencies band, occupied by them. In this context one may use next concepts- narrow-band, "wideband" and UWB signals. The borders between these concepts are conditional enough.
About structure of bank polarimetric data and atlas polarizing signature of natural objects of the Baikal region
N. V. Yumozhapova, D. D. Darizhapov, I. I. Kirbighekova
Last decades radar-tracking methods of research of terrestrial covers intensively develop. The analysis of polarizing properties of reflecting covers gives additional opportunities by way of research of spatial structure and scattering mechanisms, which improves a quality of classification of natural objects. Review of the radar remote sensing data of Buryatia submitted scanner by the images in a microwave range received by synthesized aperture radars ERS1, ERS2, JERS and Shuttle with 1994 for 2000 is submitted. The analysis coordinated and cross-polarizing signature for various areas of a wood, farmland, bogs, water surface has revealed potential opportunities on an illustration polarimetric of properties of terrestrial objects, and for their classification. Construction of the atlas polarizing signature and their characteristics in the near future is supposed.
Maps of geoelectric sections of Turkey, Iran, Afghanistan, Pakistan, Korea, and Japan
V. S. Dorzhiev, Yu. B. Bashkuev, V. R. Advokatov, et al.
Results of geoelectric mapping of the some countries of Asia with high seismic activity are presented. The methodology of the geoelectric mapping is considered. Maps of geoelectric sections of Turkey, Iran, Afghanistan, Pakistan, Korea, and Japan on a scale of 1:5 000 000 are constructed. The scale of ρj and hj has three gradations per decade.
Electrodynamics of the forest medium
Yuriy L. Lomukhin, Evgeniy B. Atutov
The model of forest is proposed as the layer of discrete random medium on the semi-conducting base layer. It are studied the absorbing and reflecting properties of forest cover in VHF range.
The concept of an atmosphere monitoring above the Baikal natural territory
Alexander V. Bazarov, Dashi D. Darizhapov, Irina I. Kirbizhekova
One of the important components of atmospheric air is ozone, which reliably protects the human and the creature on the Earth from surplus of ultra-violet radiation. As well as all other atmospheric components, the total ozone contents (TOC) varies on size, both in space, and in time. The character of these variations is formed under influence of a lot of processes both inside the atmosphere, and under influence of the external factors. The quantity of ozone depends on a lot of various circumstances: a season, latitude and longitude, conditions of atmospheric circulation, and also on solar and geomagnetic activity. It is quite probably, that ozone is one of determining climate elements of the top atmosphere, as it participates in various chemical reactions, determining thermal balance of atmosphere. The significant change TOC entails infringement of thermal balance, so also the stability of Earth atmosphere, and can cause unpredictable global accidents. With increase of volume of supervision allowing more and more in detail quantitatively to describe evolution a ozone layer, there are new certificates that the occurring changes are connected with not only anthropogenous influences, but substantially with changes of atmosphere circulation.
On the role of air temperature in humidity variations in the Northern Hemisphere in the second part of XX Century
Ashkhen A. Karakhanyan, Geliy A. Zherebtsov, Vladimir A. Kovalenko, et al.
A water vapor is the most important greenhouse gas in the atmosphere. Therefore, variations of the water vapor content can be one of the important factors determining observable changes of a climate. Based on NCEP/NCAR Reanalysis data (http://www.cdc.noaa.gov/), a complex analysis of humidity and air temperature is carried out at standard isobaric levels at middle and high latitudes in the Northern hemisphere. It is shown that atmospheric water vapor variations are produced, for the most part, by air temperature variations caused by radiation balance variations.
Experimental check of technique for calculation of critical frequency and peak height values from oblique sounding data
Anton G. Kim, Galina V. Kotovich, Viktor P. Grozov, et al.
The work is devoted to experimental check of operative technique for calculation of F2-layer parameters in path's midpoint (critical frequency and peak height) using oblique sounding data. In this work experimental data obtained in 2003-2006 by FMCW-ionosounder in Irkutsk (over different paths with different length and orientation) were used. The IRI data and experimental vertical sounding data (nearest to path's midpoint) were used for verifying of calculated values. Experimental oblique sounding data recalculation into the path's midpoint parameters was performed on the basis of the modified Smith method without consideration of Earth's magnetic field.
Comparative analysis of different methods for reconstruction of electron density profile from vertical sounding data
Anton G. Kim, Galina V. Kotovich
Electron density N(h)-profile is important geophysical characteristic and is the aim of many radiophysical methods of upper atmosphere investigation. The work is devoted to comparative analysis of the four different methods of electron density reconstruction from vertical sounding (vertical-incidence) data. The digisondes make good use of the Huang-Reinisch method for N(h)-profile reconstruction from measured vertical sounding data. The Guliaeva technique of N(h)- profile reconstruction is also widely distributed in the science environment. But this technique asks for complete height-frequency characteristic. And calculation of the peak height of the F2-layer in critical frequencies region requires the very small frequency step. The Mikhailov method (reducing this disadvantage in hmF2 calculation) was examined too. Among other things, the N(h)-profile reconstruction can be carried out via capability of the International Reference Ionosphere model to adapt by parameters which can be received from measured height-frequency characteristic. In the work comparison of the mentioned methods of N(h)-profile reconstruction was carried out on the basis of vertical sounding data obtained by DPS-4 Digisonde in Irkutsk in 2006.
Preliminary results of technique for electron density profile reconstruction from weakly oblique sounding data
Anton G. Kim, Galina V. Kotovich
In this work the technique for reconstruction of height profile of electron density N(h) from oblique sounding data was applied to weakly oblique sounding data. During the calculations it was supposed that height-frequency characteristics (HFC), obtained at the short path (the path length is ~126 km), is equal to distance-frequency characteristics (DFC), which can be recalculated into HFC of path mid-point. Recalculating of DFC into HFC was made according to modified Smith method in frames of spherically symmetric ionosphere without consideration of Earth's magnetic field. The profile N(h) was reconstructed from recalculated HFC according to Huang-Reinisch method, which is widely used in world digisonde network. Results of comparison between reconstructed N(h)-profiles with profiles obtained according to observations data of FMCW-ionosonde of ISTP, obtained at weakly oblique sounding path Usolie-Tory, and Digisonde DPS-4 in Irkutsk, near the path mid-point, are presented.
One way to universalization of vertical radio sounding data obtained by different ionospheric stations
Anton G. Kim
In practice it often is that experimental data collected during long period of time have different forms, formats and they are separately each other but it in its turn prevents their full processing the results and analysis. We need common information system to work with data as a whole for doing complex researches based on data of last periods of time but it is impossible in this situation. In case if there is the necessity of exchanging data with other observers there is also the problem of different forms. This work shows that universalization of data of the vertical ionosphere sounding, access and way of processing of experimental data obtained with the help of different ionosondes may be technically done with a success. For that we offer to transform ionograms in common form, which is matched with the software of digital ionosondes-Digisondes which are the world leaders in ground-based radiophysical researches. The scaled data in this case are saved in SAO Format which is in fact the standard among formats of archiving the data of processing, it is known in the world, and so it is very convenient for interchange of data between different researchers. Such way was successfully approbated with the data of FMCW-ionosonde obtained in condition of weak-oblique sounding and in ionograms of pulsed ionospheric stations.
Formation of positive and negative disturbances in the topside ionosphere during solar flares
L. A. Leonovich, A. V. Taschilin
The results of studies of the ionospheric response to solar flares are presented. The results are based on the observations of GPS signals and at incoherent scatter radars and on theoretical calculations. Analyzing the GPS data, the method based on a partial "shadowing" of the atmosphere by the Earth was used. This method made it possible to estimate the value of the electron content variations in the topside ionosphere during the solar flare on 14 July 2000. We obtained that according to the GPS data at altitudes of the topside ionosphere (h > 300 km) a flare is able to cause a decrease of the electron content. Similar effects of formation of a negative disturbance in the ionospheric F region were observed also during the solar flares on 21 and 23 May 1967 by the Arecibo radar. Using the theoretical model of ionosphere-- plasmasphere interaction, we study in this paper the mechanism of formation of negative disturbances in the topside ionosphere during solar flares. It is shown that the intense transport of O+ ions into the above-situated plasma caused by a sharp increase in the ion production rate and thermal expansion of the ionospheric plasma is a cause of the formation of the negative disturbance in the electron concentration in the topside ionosphere.
Astroclimate inside the dome of AZT-14 telescope of Sayan Solar Observatory
V. V. Nosov, V. M. Grigoriev, P. G. Kovaldo, et al.
This work presents the results of measurements of intradome astroclimate parameters of the AZT-14 telescope of Sayan solar observatory of the ISTP SB. The picture of airflows concerned with the warm air run-out though leaky connections and air mixing inside the telescope after dome opening is obtained. It is shown that the value of the structure characteristic of the refractive index Cn2 in closed and open dome can 1.5-2 times differ. Essential turbulence intensification in front of the entrance telescope mirror when dome opening is ascertained. Strongly unstable stratification near the receiver is observable, caused by the stair opening in the concrete floor of the dome, which can result in intensification of the refractive index fluctuations in the presence of even small heat sources. Conclusions are drawn from the measurements, which can be related to all telescope of the considered class. It is necessary to prevent foreign heat sources in the dome and block warmer airflows from the stair opening; astronomical observations are to be carried out after completion of transient processes related to the dome opening.
The peculiarities of the manifestation of long-time oscillations in variations of critical frequency of an ionosphere F2-layer
G. V. Vergasova, E. S. Kazimirovsky, N. M. Polekh
On a database of vertical sounding of the ionosphere, received on middle-latitude stations Irkutsk (52.5°N, 103°E), Moscow (55.5°N, 37.3°E), and Boulder (40.0°N, 254.7°E) we investigated features of display of the long-period fluctuations (with the periods of internal atmospheric planetary waves) in variations of critical frequency of a F2-layer for a maximum and a minimum of solar activity. Existence of fluctuations with the periods ~7, ~10, ~16, ~22 and ~27 days has been revealed. Their amplitude and time of existence essentially depend on a level of solar activity, a season and regional features. It is shown, that in a minimum of solar activity fluctuations with the shorter periods (<15 days), and within a maximum - with longer (> 20 days) were more often observed. Fluctuations with the periods ~ 16 days are most on a regular basis shown, in the summer they can be present during two months. It is established, that fluctuations such as planetary waves in Eastern Siberia are observed approximately in 2 times more often, than in Northern America.
Influence of the ionosphere on radio astronomical signals according to GPS sounding and ionospheric modeling
E. L. Afraimovich, G. Ya. Smolkov, P. V. Tatarinov, et al.
VHF signals are widely used for observations of the Sun and pulsars. Nowadays huge VHF radio astronomical arrays (LOFAR, 30-240 MHz; MIRA, 80-300 MHz) are being constructed to record pulsar radiation at maximum possible distance. Registration of VHF solar radio emission is very important along with other methods of monitoring of coronal mass ejections. At the interpretation of the data it is necessary to take into account possible distortions of these signals at the Earth ionosphere. We have developed a method and software for calculation of the ionosphere measure of rotation (RM), and the measure of dispersion (DM). We used the ionosphere model IRI-2001, magnetic field model IGRF-10 and values of ionosphere total electron content as deduced from GPS measurements. The obtained values of the ionosphere DM and RM were recalculated into characteristics of phase delay, Faraday amplitude modulation and polarization changes. In the paper we made calculations for different levels of geomagnetic activity and for different angular position of radio sources as well.
Measurements of the thermal emission of Chita atmosphere in the magnetic storm of 2006 December 14
G. S. Bordonskiy, A. A. Gurulev
Strong emission of atmosphere at magnetic storm of 2006 December 14 at 8.6 mm, 3.3 mm, and 8-12 micron wavelengths in Chita (Trans Baikal Region) was observed. Hypothesis of appearance of charged particles streams and its influence on atmospheric emissivity are discussed.
Theoretical description of the temperature distribution in the Earth atmosphere
S. O. Gladkov
The temperature dependence T(z) from high z of Earth surface is described. It's shown that T(z) is a result of solving of the strong nonlinear differential equation.
Microwave radiation scattering measurements of different types of lake ice covers
G. S. Bordonskij, A. A. Gurulev, S. D. Krylov, et al.
The results of radar measurements of ice covers at 2.2 cm and 5.6 cm wavelengths were presented. It is shown that from measurements of backscattering coefficient one can determined concentration of highest water vegetation which is freezing in fresh-water ice cover. For the case of saline ice, the state of upper layers can be determined.
Ionospheric F2-layer approaches new wave closure
The concentric structure of closed waves of the space-mass continuum carrying the Earth is discovered and shown by means of the self-organizing algorithm based on the law of increment symmetry conservation. As a result of the Universe expansion, the positive phases of this structure are also subjected to the expansion tensions, and that of negative the contraction tensions. The tensions are directed to the medium with the reverse sign, reinduced by the neighboring waves as natural. They also form the fine structure manifested by layers in the atmosphere, ionosphere and space in superposition. Cases of the negative continuum achievement by fragments are expressed by the radiomirrors. Cases of the negative value achievement from all sides (cases of the new waves closure) are expressed by nova and supernova stars, explosions and sharp contraction of the planet (depends on position of the layer, i.e., lower or higher the surface). The proximity of the ionospheric F2-layer to the new wave closure is shown. The possibilities of tension extinction or decrease in the layer to the safe value are discussed.
The neural network prediction dynamics of the ozone layer
Irina Yu. Sakash, Juliy P. Lankin
The study data on the adaptive neural network modeling are represented. The networks trained using the back-propagation algorithm, widespread in the contemporary neural automatics. Stratospheric and tropospheric ozone concentration forecast issues are addressed. The neural networks have been used for the purposes of developing ozone concentration prognostic models as well as of forecasting TOC (total ozone concentration) values within a week period.
Evolution of the basic micrometeorological parameters during the total solar eclipse of 29 March 2006 at Manavgat, Turkey
Alexey D. Stoev, Penka V. Stoeva, Nadya Kiskinova, et al.
Changes in the physical state of the 10m ground atmospheric layer owing to a sharp drop in the direct solar radiation have been observed during the March 29, 2006 total solar eclipse (TSE). Observations were conducted near the town of Manavgat, Turkey. Temperature, humidity, barometric pressure, speed and direction of the wind were measured with a fast automatic meteorological station with high resolution specially designed for this event. In addition, temperature in the 20 cm soil layer were measured. The difference in temperature changes at different heights before, during and after the total phase was in the interval 16°C - 17°C. Minimum of the air temperature during the TSE was measured 2 min after the end of the total phase. Atmospheric pressure was sharply changed from 1021 hPa - at the beginning of the eclipse (09h 38min 28s) to 1028 hPa - 1 min 26 s after the end of the total phase (10h 58min 49s). The relative humidity increases from 72% up to ~76% after the total phase. Speed of the wind was measured in 5 minutes during the partial phases and in 1 min during the total phase. It decreases with 3m/s just before the total phase and increases after the end of the total phase changing its direction from south-east to north-east, which coincides with the motion of the lunar shade on the earth.
Spatial and temporal variations of electric field of the atmosphere at the Lake Baikal coastal area
P. G. Kovadlo, A. A. Krechetov, V. A. Obolkin, et al.
The main purpose of this investigation was to estimate the influence of local natural condition on behavior of electric field of the atmosphere. Observations were conducted nearby Listvyanka settlement at a south-west coast of the Lake Baikal at three sites with different natural conditions and with minimal anthropogenic influence. The main permanent observation site was organized at the territory of Baikal Astrophysical observatory (BAO) - at one of coastal hills about 220 meters above lake level. Temporally measurements were conducted (synchrony with the main site): in September - inside the narrow and deep stream valley, at the distance about 2 km from the main observation site; in March - at the lake ice, at the distance 5 km from the shore. Observations at the main site were conducted also at two levels: near ground surface and at the top of solar telescope tower (26 meters above the ground).