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Vitreous basalts and plagioclase lapilli from Tolbachik Volcano studied by high-temperature gas chromatography reveal features of a fluid regime uncommon to suprasubduction melts. Prominent depletion in volatiles confirms the anomalous behavior of the Tolbachik fluid systems. Vitreous basalts contain minor amounts of water (0.16-0.27 wt.%) and carbon dioxide (95-440 ppm). New data on volatiles in the Tolbachik plagioclase lapilli show very low contents of CO2 and total gas (exclusive of H2O) and enrichment in reduced fluids (CO and CH4) relative to the basalts. In general, analysis of basalts and plagioclase lapilli from different eruptions trace a progressive increase in reduced fluids (CO and CH4) and decrease in CO2 and total gas from past to present events. The concentrations of CO2 decrease, while those of CO and CH4 in basalts and plagioclase lapilli increase systematically with an increase in FeO/MgO ratios and K2O contents in the lavas and in anorthite component in plagioclase.

The influence of parental melts on the chemical composition of rock-forming minerals of alkaline lamprophyres (monchiquites) referred to as the volcanic series of porphyritic potassic alkaline-ultrabasic rocks was studied in the Tomtor alkaline-ultrabasic carbonatite massif (Yakutia) hosting a unique deposit of Sc-REE-Y-Nb ores. Previous fluid-melt inclusion study showed that these rocks formed from two mixing alkaline-basic melts of different alkalinity. A detailed study of the chemical composition of minerals revealed a repeated irregular zoning in most of phenocrysts, which reflects the influence of different parental magmas and their mixing. It was established that the cores of diopside phenocrysts (Di I) with inclusions of Na-Fe-rich silicate melts have a low Mg-number and low contents of Ti, Al, and Ca and high contents of Na and Mn. The intermediate zones of phenocrysts (Di II) containing inclusions of K-Mg-rich silicate melts show a high Mg-number and are rich in Ti and Al and poor in Mn and Na. Groundmass grains and rims (and, sometimes, intermediate zones) of diopside phenocrysts often have a mixed Di I-Di II composition with slightly elevated contents of Mg, Ti, and Al. Amphibole phenocrysts, like the diopside ones, have both zones with low Mg contents and high Na/K ratios and Mn contents and zones with high Mg contents, low Na/K ratios, and low Mn and elevated Ti contents. Phlogopites are also of two varieties: highly magnesian, with high contents of Si and K and low content of Mn, and lowly magnesian, with low contents of Si and K and high content of Mn. Ilmenite, titanomagnetite, and fine grains of femic minerals are mostly of mixed varying composition. The chemical composition of rock-forming minerals, especially zoned phenocrysts, evidences that they crystallized with the participation of two alkaline-basic melts: Na-Fe-rich silicate melt enriched in Mn and K-Mg-rich silicate melt enriched in Ti but depleted in Mn.

Geochemical and U-Pb geochronological studies have shown that the alkali syenites of the China massif have an age of 311.4 ± 1.8 Ma and potassic specialization in contrast to most massifs of the Vitim alkaline-magmatism zone. The rocks are similar in geochemistry to the nepheline syenites of the Synnyr massif, dated at 289.5 ± 3.5 Ma. The alkali syenites of the China massif formed, most likely, from crustal protoliths.

According to the long-term (1963-2000) observational data on depth of the Secchi Disk visibility, the main peculiarities of the annual cycle of transparency distribution in the surface water layer of the north-western Black Sea are considered. The statistical estimates of the seasonal variations in the areas differing in the degree of influence of river and open-sea water flow on their hydrophysical parameters are derived. Intra-annual transparency variations in these areas are in a good agreement with the intra-annual variations in phytoplankton biomass and water salinity. It is shown that long-term (1950-2013) intra-annual seasonal transparency variations (according to the data measured and reconstructed by means of a neural network model) show a satisfactory agreement with the intra-annual variations in the hydrobiological parameters. The dependences of the variations in these parameters on the regional meteorological conditions within El Niño - Southern Oscillation period and within the period of its absence are studied.

We describe a new algorithm for retrieving the atmospheric fine particulate matter total column (particles less than 1.0 and 2.5 μm) from multi-spectral satellite images in visible and IR regions of the electromagnetic spectrum. The algorithm is based on the regression relations between the top of atmosphere (TOA) reflectance, microphysical parameters of aerosol, and geometrical parameters of satellite scene. The regression equations are derived from the TOA reflectance calculations in the spectral channels of the satellite instrument for the ensemble of random generated parameters of the atmospheric radiative transfer model and the geometrical parameters of the satellite scene. Subsequently, this allows real-time mapping the fine particulate matter pollutions directly from the satellite images without solving ill-posed inverse problems of the solar radiation transfer in the atmosphere and aerosol light scattering. The proposed algorithm is implemented and tested for MERIS (Medium Resolution Imaging Spectrometer) satellite instrument. The comparison of the MERIS-retrieved total fine particulate matter content in the atmosphere with AERONET (Aerosol Robotic Network) data shows the standard deviation ~ 0.5 μg/cm². The application of the developed algorithm to real-time monitoring of the regional and transboundary transport of the atmospheric particulate matter pollutants during the wildfires is demonstrated.

A model of the solar radiation transfer in the Earth's atmosphere is developed for explicit calculations of the transfer characteristics of the atmosphere (reflectance, transmission, and spherical albedo) in its visible and near-IR transparency windows depending on the surface air pressure (or terrain elevation), the aerosol optical parameters, and angles indicating the position of the Sun and the satellite system with respect to the Earth's target. The model is based on the spectrally dependent approximations obtained using the atmospheric radiative transfer code DISORT. The sensitivity of underlying surface spectral albedo retrieval from top-of-atmosphere reflectance to vertical distribution of atmosphere optical parameters is investigated. The algorithm is designed for the atmospheric correction of multispectral satellite images with the developed model and applied to MERIS instrument (Medium Resolution Imaging Spectrometer). It is shown that accounting of optical properties of the atmosphere and adjacency effects in the processing of satellite images substantially improves visibility of underlining surface targets and rendering their spectral reflectance parameters

The possibilities and limitations of determining the skewness and kurtosis of sea surface slopes by spaceborne optical scanners are analysed. It is shown that these data do not allow precise retrieval of the values of skewness and kurtosis. The empirical probability density of slopes, determined according to the optical scanner data, is defined in a limited range of slopes. The Cox-Munk model used in the calculations is also defined in a limited area.

The feasibility of Levenberg-Marquardt method, modified for the case of inaccessibility of a priori covariance matrices for methane vertical profiles, for atmospheric methane total column amount retrieval from the spectra measured by IASI/METOP is studied. The method and algorithm were implemented into software package together with iterative evaluation of a posteriori covariance matrices and averaging kernels for each individual case of retrieval. This allows selection of the results on the basis of properties of both matrices. The comparison between our results and IASI standard methane products retrieved from the same spectra shows their satisfactory agreement.

The action of enhanced UV radiation at the 308 nm wavelength on the photosynthetic apparatus of Siberian spruce seedlings (Picea obovata Ledeb.) from June to August has been studied in two-year experiment. The negative effect on the photosynthetic apparatus of spruce needles is ascertained, with a pronounced cumulative effect. The suppression of the photosynthesis rate and transpiration intensity in the radiation-exposed two-year spruce needles and current-year spruce needles, primordia formed in July-September of the previous vegetation period, is shown to be deeper during the second vegetation period as compared to the first one. We revealed that the water balance of spruce needles corresponded to seasonal norms in the both groups during the experiment. The decrease of the transpiration intensity in the spruce seedlings exposed to radiation as compared to the control group is conditioned by a need in maintaining the water homeostasis in the needles. The experimental group of spruce seedlings showed a weaker correlation between the photosynthesis rate and transpiration intensity than the control group, which is clearly pronounced in the two-year needles exposed to the radiation.

We have measured the sedimentation rates of the pollen particles of several species of anemogamous plants (including those introduced by a man) growing in Western Siberia (pine trees: ordinary, Siberian, mountain, Crimean; inoculum hemp, rib grass). It is shown that upon spraying, the anemophilous pollen particles are represented by both single pollen grains and agglomerates of two or more grains. The portion of agglomerates in the total number of particles deposited is estimated. The sedimentation rates of the pollen particles are determined. The sedimentation rates of the pollen agglomerates of one or more grains are measured. The dependence of the sedimentation rate on the number of grains in an agglomerate is established.