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71.
E. I. Terez G. A. Terez A. V. Kozak S. V. Kuz’min 《Bulletin of the Crimean Astrophysical Observatory》2013,109(1):80-85
Water-vapor content determination via solar-radiation absorption measurement in the watervapor absorption band ρ is described. The investigation was carried out with an automatic solar photometer, making it possible to record solar radiation in the band ρ and adjacent absorption-free spectrum sections. Regular observations have been performed in Crimea (Simferopol, 44.7 N and 34.1 E) from 2001 to the present. According to the observation data, the water-vapor content W in the atmosphere of Crimea is seasonally dependent, while the annual average value is almost constant. 相似文献
72.
Tymon Zieliński Tomasz Petelski Przemysław Makuch Agata Strzałkowska Agnieszka Ponczkowska Krzysztof M. Markowicz Georgius Chourdakis George Georgoussis Susanne Kratzer 《Acta Geophysica》2012,60(5):1359-1385
This paper presents the results of the studies of aerosol optical properties measured using lidars and sun photometers. We describe two case studies of the combined measurements made in two coastal zones in Crete in 2006 and in Rozewie on the Baltic Sea in 2009. The combination of lidar and sun photometer measurements provides comprehensive information on both the total aerosol optical thickness in the entire atmosphere as well as the vertical structure of aerosol optical properties. Combination of such information with air mass back-trajectories and data collected at stations located on the route of air masses provides complete picture of the aerosol variations in the study area both vertically and horizontally. We show that such combined studies are especially important in the coastal areas where depending on air mass advection directions and altitudes the influence of fine or coarse mode (in this case possibly sea-salt) particles on the vertical structure of aerosol optical properties is an important issue to consider. 相似文献
73.
Krzysztof M. Markowicz Tymon Zieliński Sandra Blindheim Michael Gausa Anna K. Jagodnicka Aleksandra E. Kardas Wojciech Kumala Szymon P. Malinowski Tomasz Petelski Michał Posyniak Tadeusz Stacewicz 《Acta Geophysica》2012,60(5):1308-1337
This paper presents the measurements of a vertical structure of aerosol optical properties performed during the MACRON (Maritime Aerosol, Clouds and Radiation Observation in Norway) campaign, which took place in July and August 2007 at ALOMAR observatory on Andøya island (69.279°N, 16.009°E, elevation 380 m a.s.l.). The mean value of the aerosol optical thickness (AOT) at 500 nm during campaign was 0.12. Significant increase of the AOT above longtime mean value was observed on 7 and 8 August 2007 when the AOT exceeded 0.4 at 500 nm. Analyses of back trajectories show the aerosol transported from over Africa and Central Europe. The aerosol extinction coefficient obtained from the synergy of ceilometer and sun photometer observations reached 0.05–0.08 km?1 (at 1064 nm) in the dust layer. The single scattering albedo at the ALOMAR observatory decreased during the dust episode to 0.93–0.94, which indicates some absorptive aerosols in the lower PBL. 相似文献
74.
The aim of this paper is to analyse the influence of the source of various elevation data on hydraulic modelling in open channels. In the research, digital terrain models from different datasets were evaluated and used in two-dimensional hydraulic models. The following aerial and satellite elevation data were used to create the representation of terrain–digital terrain model: airborne laser scanning, image matching, elevation data collected in the LPIS, EuroDEM, and ASTER GDEM. From the results of five 2D hydrodynamic models with different input elevation data, the maximum depth and flow velocity of water were derived and compared with the results of the most accurate ALS data. For such an analysis a statistical evaluation and differences between hydraulic modelling results were prepared. The presented research proved the importance of the quality of elevation data in hydraulic modelling and showed that only ALS and photogrammetric data can be the most reliable elevation data source in accurate 2D hydraulic modelling. 相似文献
75.
L. V. Kozak S. P. Savin V. P. Budaev V. A. Pilipenko L. A. Lezhen 《Geomagnetism and Aeronomy》2012,52(4):445-455
The statistical features of the magnetic field and ion flux fluctuations in the boundary regions of the Earth’s magnetosphere have been studied on different timescales based on the Interball satellite measurements. Changes in the form and parameters of the probability density function have been studied for the periods when the satellite was in the solar wind plasma, different magnetosheath regions, and the turbulent boundary layer (TBL) at the polar cusp outer boundary. Variations in the probability density function maximum (P 0) and the kurtosis value as characteristics of the turbulence property evolution on different timescales have been studied. Two asymptotic regimes of P 0, which are characterized by different power laws, have been found. The structural functions of different orders and the types of diffusion processes in different regions, depending on time variations in the generalized diffusion coefficient, have been studied in order to analyze the character of diffusion processes. For the magnetosheath regions, TBL, and polar cusp, it has been found that the diffusion coefficient increases in the course of time (i.e., the regime of superdiffusion has been obtained). In the foreshock region before the main shock, turbulent processes are described by the Kolmogorov model of classical diffusion. 相似文献
76.
The forced regime of groundwater development is an efficient method of enhancing the reliability of water supply to cities, where it is based on the joint use of surface water and groundwater and suffers from their deficiency in dry years that occur with certain probability. To solve the problem of water supply to Vladivostok, it is planned to use groundwater of the Razdol??ninskii Area of the Pushkinskoe Groundwater Deposit. The possibility to cover water deficiency by changing the operation regime of water intake is proved. The total reserves explored in 1983 are 124.5 thous. m3/day. Mathematical modeling was used to substantiate the possibility of the use of periodic forced regime of water intake operation with the capacity of 250 thous. m3/day with its subsequent decrease to 60 thous. m3/day. 相似文献
77.
78.
Delphine Yeghicheyan Dominique Aubert Martine Bouhnik‐Le Coz Jrme Chmeleff Sophie Delpoux Irina Djouraev Guy Granier Franois Lacan Jean‐Luc Piro Tristan Rousseau Christophe Cloquet Aurlie Marquet Christophe Menniti Catherine Pradoux Rmi Freydier Emmanoel Vieira da Silva‐Filho Krzysztof Suchorski 《Geostandards and Geoanalytical Research》2019,43(3):475-496
The natural river water reference material SLRS‐6 (NRC‐CNRC) is the newest batch of a quality control material routinely used in many international environmental laboratories. This work presents a nine‐laboratory compilation of measurements of major and trace element concentrations and their related uncertainties, unavailable in the NRC‐CNRC certificate (B, Cs, Li, Ga, Ge, Hf, Nb, P, Rb, Rh, Re, S, Sc, Se, Si, Sn, Th, Ti, Tl, W, Y, Y, Zr and REEs). Measurements were mostly made using inductively coupled plasma‐mass spectrometry. The results are compared with equivalent data for the last batch of the material, SLRS‐5, measured simultaneously with SLRS‐6 in this study. In general, very low concentrations, close to the quantification limits, were found in the new batch. The Sr isotopic ratio is also reported. 相似文献
79.
The paper describes results of microgravity measurements made on the surface over an underground geo reactor where experimental coal gasification was performed in a shallow seam of coal. The aim of the research was to determine whether, and to what extent, the microgravity method can be used to detect and image a coal gasification zone, especially caverns where the coal was burnt out. In theory, the effects of coal gasification process create caverns and cracks, e.g., zones of altered bulk density. Before the measurements, theoretical density models of completely and partially gasified coal were analysed. Results of the calculations of gravity field response showed that in both cases on the surface over the gasification zone there should be local gravimetric anomalies. Over the geo reactor, two series of gravimetric measurements prior to and after gasification were conducted. Comparison of the results of two measurement series revealed the presence of gravimetric anomalies that could be related to the cavern formation process. Data from these measurements were used to verify theoretical models. After the experiment, a small cavern was detected at the depth of the coal seam by the test borehole drilled in one of the anomalous areas. 相似文献
80.
Krzysztof Godziewski Sawomir Breiter Wojciech Borczyk 《Monthly notices of the Royal Astronomical Society》2008,383(3):989-999
We describe numerical tools for the stability analysis of extrasolar planetary systems. In particular, we consider the relative Poincaré variables and symplectic integration of the equations of motion. We apply the tangent map to derive a numerically efficient algorithm of the fast indicator Mean Exponential Growth factor of Nearby Orbits (MEGNO), a measure of the maximal Lyapunov exponent, that helps to distinguish chaotic and regular configurations. The results concerning the three-planet extrasolar system HD 37124 are presented and discussed. The best-fitting solutions found in earlier works are studied more closely. The system involves Jovian planets with similar masses. The orbits have moderate eccentricities, nevertheless the best-fitting solutions are found in dynamically active region of the phase space. The long-term stability of the system is determined by a net of low-order two-body and three-body mean motion resonances. In particular, the three-body resonances may induce strong chaos that leads to self-destruction of the system after Myr of apparently stable and bounded evolution. In such a case, numerically efficient dynamical maps are useful to resolve the fine structure of the phase space and to identify the sources of unstable behaviour. 相似文献