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971.
The methods are considered to solve the problem of secure isolation of radioactive waste containing long-lived products of nuclear fuel processing with a half-life of tens of thousands years (plutonium etc.). The methodology of long-term projection of average annual surface air temperature and total precipitation is proposed. Taking into account the possible scenarios of the development of the global socioeconomic system, variations due to the anthropogenic impact in average annual temperature at the Northern Hemisphere mid-latitudes for the period till 2300 are estimated. Based on paleoclimatic data, projections of natural trends in global average annual temperature and total precipitation till the year 3000 are developed. Taking into account the anthropogenic component, the projective ranges of these climatic parameters in the Vyatka River basin in 2100-3000 are evaluated. 相似文献
972.
E. V. Kharyutkina S. V. Loginov Yu. V. Martynova 《Russian Meteorology and Hydrology》2016,41(6):435-438
The estimates of spatiotemporal variability of climatic parameters in West Siberia are obtained over the period of 1976-2014. It is revealed that this variability is affected by the parameters of atmospheric circulation such as wind speed components, relative vorticity, and large-scale circulation indices. It is found that in winter the warming changed into the cooling that is particularly associated with the change in atmospheric circulation patterns described by the SCAND index. 相似文献
973.
A. M. Zvyagintsev N. S. Ivanova I. N. Kuznetsova V. A. Lapchenko N. V. Tereb 《Russian Meteorology and Hydrology》2016,41(9):662-664
The review is compiled on the basis of the operation of the total ozone (TO) monitoring system in the CIS and Baltic countries that functions in the operational regime at the Central Aerological Observatory. The monitoring system uses the data from the national network equipped with M-124 filter ozonometers under methodological supervision of the Main Geophysical Observatory. The quality of the functioning of the entire system is under the operational control based on the observations obtained from the OMI satellite equipment (NASA, the United States). The basic TO observation data are generalized for each month of the second quarter of 2016 and for the quarter as a whole. The data of routine observations of surface ozone content carried out in the Moscow region and Crimea are also presented. 相似文献
974.
E. V. Gorbarenko 《Russian Meteorology and Hydrology》2016,41(11-12):789-797
Variations in radiation fluxes and the factors that define them and their redistribution in the atmosphere are analyzed using the data of long-term ground-based measurements at the Meteorological Observatory of Lomonosov Moscow State University. It is demonstrated that since the middle of the 1990s trends in many atmospheric radiation parameters have changed as compared to the trends observed in the previous years. For some parameters the trends are significant, are kept for a long period of time, and. hence, can be considered as climate changes. The potential effects of these changes on the regional warming are assessed. 相似文献
975.
D. A. Yarovaya 《Russian Meteorology and Hydrology》2016,41(8):535-543
The statistical study of intense mesoscale cyclones formed in the Black Sea region in 1979-2013 is carried out using the surface wind data of the RegCM climate model. Such cyclone parameters as intensity, lifetime, area, height, and trajectories over the sea as well as the place and time of origin are considered. The distribution of mesocyclones by months and times of day is considered. The obtained results are compared with the results of a statistical study on the Black Sea mesocyclones based on the PRECIS climate model. Possible causes for differences in data on the intensity and number of mesocyclones simulated by RegCM and PRECIS models are considered. 相似文献
976.
M. G. Aleksanina A. S. Eremenko A. A. Zagumennov V. A. Kachur 《Russian Meteorology and Hydrology》2016,41(9):620-628
The results are presented of using a new approach that helps to detect and compute the parameters of eddies in the ocean and tropical cyclones in the atmosphere based on satellite imagery. The approach is based on the concept of dominant orientation of thermal contrasts (DOTC). DOTC is an angle of the statistically significant orientation of brightness contrast in the specified vicinity of the image. DOTC highly correlates with the directions of flows; it is a base for construction of models for identification of eddy motions, namely, synoptic eddies in the oceans and tropical cyclones in the atmosphere. The model-based identification of one or another eddy allows estimating such parameters as the center position, shape, size, and sign (cyclone or anticyclone) of the eddy, and the size of the tropical cyclone eye. Based on the proposed approach, technologies of automatic identification and monitoring of oceanic eddies and tropical cyclones are developed. The results of the practical use of these technologies are presented for the recent years. 相似文献
977.
Kiran Chand Thumaty Rakesh Fararoda Suresh Middinti Rajashekar Gopalakrishnan C. S. Jha V. K. Dadhwal 《Journal of the Indian Society of Remote Sensing》2016,44(1):31-39
Reliable and accurate estimates of tropical forest above ground biomass (AGB) are important to reduce uncertainties in carbon budgeting. In the present study we estimated AGB of central Indian deciduous forests of Madhya Pradesh (M.P.) state, India, using Advanced Land Observing Satellite – Phased Array type L-band Synthetic Aperture Radar (ALOS-PALSAR) L-band data of year 2010 in conjunction with field based AGB estimates using empirical models. Digital numbers of gridded 1?×?1° dual polarization (HH & HV) PALSAR mosaics for the study area were converted to normalized radar cross section (sigma naught - σ0). A total of 415 sampling plots (0.1 ha) data collected over the study area during 2009–10 was used in the present study. Plot-level AGB estimates using volume equations representative to the study area were computed using field inventory data. The plot-level AGB estimates were empirically modeled with the PALSAR backscatter information in HH, HV and their ratios from different forest types of the study area. The HV backscatter information showed better relation with field based AGB estimates with a coefficient of determination (R2) of 0.509 which was used to estimate spatial AGB of the study area. Results suggested a total AGB of 367.4 Mt for forests of M.P. state. Further, validation of the model was carried out using observed vs. predicted AGB estimates, which suggested a root mean square error (RMSE) of ±19.32 t/ha. The model reported robust and defensible relation for observed vs. predicted AGB values of the study area. 相似文献
978.
979.
Kunlun Yan Nesreen I. Ziedan Hongping Zhang Wenfei Guo Xiaoji Niu Jingnan Liu 《GPS Solutions》2016,20(2):225-237
An open loop tracking architecture, which tracks GPS signals under weak and challenging conditions, is analyzed. The in-phase and quadrature-phase integration pair is regarded as a single tone complex signal. An FFT-based method is used as a frequency discriminator to estimate the Doppler frequency residual of the single tone signal. Another FFT-based method applies complex squaring to eliminate the effect of the navigation data bits polarities. The performance of the FFT-based discriminators is assessed in three criteria. Those criteria are the signal strength and dynamic range that can be tracked and the accuracy of the estimated Doppler frequency. In addition, the performance of the discriminators is analyzed to provide the theoretical and simulated peak detection probability. The results indicate that the FFT discriminator can track signals about 5 dB weaker than the signals that can be tracked by the complex squared FFT discriminator. In a quasi-static environment, the Doppler frequency residual can be assumed to be around zero, which can enable the FFT-based discriminators to track signals with approximately 2 dB less power. Moreover, the performance of the FFT-based discriminators is compared with the performance of two other frequency discriminators, namely the fast–slow and power-based. The comparison results indicate that these two frequency discriminators give higher frequency estimation accuracy, but they have a narrower dynamic range. 相似文献
980.
A. A. Borisov 《Petrology》2016,24(2):117-126
Mutual interaction of redox pairs resulting in the origin or decomposition of a metal phase is analyzed based on the concept of intrinsic oxygen fugacity. Reactions are suggested that may be responsible for the synthesis (or decomposition) of submicrometer-sized metal nuggets when experimental melts are quenched and can explain the possible crystallization of Pt—Fe alloys when basaltic melts cool and elucidate the nature of color of Au-bearing ruby glass. Possible disproportionation reactions of certain lower oxides into a higher oxide and respective metal in cooled silicate melts are discussed. 相似文献