A ring of traveling ionospheric disturbances around Moscow megapolis

Doklady Earth Sciences - According to interferometric data of radio waves from GPS satellites, which are received in Moscow region on the stations of the Moscow Navigation-Geodesic Support Network...     

Observations of the atmosphere composition in the Moscow megapolis from a mobile laboratory

Doklady Earth Sciences -     

Weekly cycle of meteorological parameters over Moscow region

Analysis of aerological radiosonde data in the period of 2000–2009 shows that, in the warm period of the year, the air temperature over Moscow region is higher in the first half of the week than in the second half. The statistically significant (at the α = 0.05 significance level) air temperature differences between Tuesday and Friday, as well as between Wednesday and Friday, reach 0.8°C and are manifested in the atmospheric boundary layer (according to nighttime observations) and in the middle troposphere (according to daytime observations). In the upper troposphere, the weekly temperature cycle positively correlates with the weekly cycle of air pressure, while in the lower troposphere, it positively correlates with the weekly cycle of water vapor content. In the upper troposphere, the southerly wind is strengthened in the middle of the week, and northerly wind is strengthened on the weekend. In the boundary layer, the temperature changes induce the weekly cycle of the static stability of the atmosphere.     

Peculiarities of electric and magnetic tipper variations caused by meteorological disturbances in the atmosphere

We present the results of the analysis of experimental data of synchronous observations of variations in the electric and magnetic fields as well as acoustic oscillations in the surface zone of the Earth compared with variations in the meteorological parameters. We demonstrate the synchronous variations in these fields and atmospheric parameters. We revealed, for the first time, not only synchronous but also advancing manifestations of the geomagnetic field perturbations. We introduce a new parameter: the inverse magnetic tipper whose variations during atmospheric perturbations are clearly manifested compared with the variations in the magnetic tipper.     

Extreme carbon monoxide pollution of the atmospheric boundary layer in Moscow region in the summer of 2010

Using data of spectroscopic measurements in Moscow and Moscow region and data of ecological monitoring from Ostankino TV Tower, it has been found that, in the period of intense smoke blanketing of the atmosphere in summer 2010 due to large-scale forest-peat fires on the territory of the European part of the Russian Federation, the carbon monoxide content in the boundary layer and in the atmospheric depth of Moscow region reached the extremely high level of 8 g/m², or 17 ×10¹⁸ mol/cm², and the carbon monoxide concentration in the near-ground atmospheric layer increased to 37.5 mg/m³, i.e., an unprecedentedly large value for Moscow and more than a factor of 7 larger than the one-time maximum permissible concentration for carbon monoxide MPC_ot = 5 mg/m³. In the first decade of August, when intense smoke blanketing of the Moscow region was observed, the average carbon monoxide concentrations varied in the range from approximately 3 to 7 m/g³, i.e., an order of magnitude larger than the annual average concentrations calculated according to data of measurements in 2009. The probabilities of exceeding MPC_ot and multiples of MPC_ot are calculated. Analysis of data of thermal sensing showed that an important feature of the atmospheric boundary layer over the city was a high stability of the lower atmospheric layer with the thickness of 150–200 m, and also long-term nighttime and morning inversions of the air temperature in this layer.     

A VES-IP survey near the geophysical station of Moscow State University, in the Kaluga region

Due to the progress in instrumentation and methods in the most recent decade apparent resistance curves have been supplemented by accurate apparent chargeability curves at some frequencies up to an electrode spacing of 500 m. The comparison of the induced polarization frequency characteristics makes it possible to arrive at additional conclusions on the nature of anomalies. The results of vertical electrical and induced polarization sounding survey (VES-IP) that were carried out under the geophysical field studies of the Moscow State University are described.     

The city of Moscow and the Moscow agglomeration

Lower rainfall and a longer dry season appear to have characterised SE Asia during the Quaternary Glacials. This had an important effect on vegetation and on landform development, particularly on weathering, river regimen, coastal features and planation. The low Glacial sea levels are generally thought not to have caused river incision and deposition of rather coarse-textured materials is considered more characteristic. Incision was mainly tied to the Interglacial and Holocene humic tropical conditions when vegetation interfered with non-concentrated surface wash. Clay blankets were deposited off-shore and also above the waterline. This concept has consequences for the Quaternary chronology in SE Asia.     

Anthropogenic changes in the hydrosphere

After a short review of the development of the concept of anthropogenic changes in the hydrosphere and their classification the authors show that man's impact on water chiefly concerns dynamically renewed water storage.The paper deals with the following problems: the hydrological importance of non-irrigation farming, the effect of water resourcès use for irrigation and water supply, intrazonal water transportation, streamflow regulation with the help of surface and underground reservoirs, water quality management which is more effectively achieved by combatting pollution at cause.In conclusion the authors consider there is a real possibility of improving the water component of the environment.     

Impact of global warming on cyclonic disturbances over south Asian region

A state-of-the-art regional climate modelling system, known as PRECIS (Providing REgional Climates for Impacts Studies) developed by the Hadley Centre for Climate Prediction and Research, UK is applied over the Indian domain to investigate the impact of global warming on the cyclonic disturbances such as depressions and storms. The PRECIS simulations at 50 × 50 km horizontal resolution are made for two time slices, present (1961–1990) and the future (2071–2100), for two socioeconomic scenarios A2 and B2. The model simulations under the scenarios of increasing greenhouse gas concentrations and sulphate aerosols are analysed to study the likely changes in the frequency, intensity and the tracks of cyclonic disturbances forming over north Indian Ocean (Bay of Bengal and Arabian Sea) and the Indian landmass during monsoon season. The model overestimates the frequency of cyclonic disturbances over the Indian subcontinent in baseline simulations (1961–1990). The change is evaluated towards the end of present century (2071–2100) with respect to the baseline climate. The present study indicates that the storm tracks simulated by the model are southwards as compared to the observed tracks during the monsoon season, especially for the two main monsoon months, viz., July and August. The analysis suggests that the frequency of cyclonic disturbances forming over north Indian Ocean is likely to reduce by 9% towards the end of the present century in response to the global warming. However, the intensity of cyclonic disturbances is likely to increase by about 11% compared to the present.     

Anthropogenic contamination of groundwater with nitrate in arid region: case study of southern Hodna (Algeria)

In southern Hodna, an arid region of Algeria, the extension of irrigated agriculture and overexploitation of groundwaters have led to a rupture with traditional land use by pastoralism. Due to the arid conditions, groundwaters are the only water resources for man and irrigation. This study focuses on nitrate contamination of groundwaters and its increase since the last 40 years, on the basis of two archives and recent analyses. The chemical facies of waters is sulphate-chloride, the risk of salinity is moderate to large. The sodicity risk, as estimated by the SAR, is low due to the large salinity and the sandy soil texture. Nitrate contamination of deep groundwater is a clear evidence when recent data are compared to the historical data. From 1996 to 2008, the proportion of samples with NO ₃ ^? concentrations larger than 50 mg/L increases from 24 to 61 %, the proportion of samples with NO ₃ ^? concentrations larger than 100 mg/L increases from 12 to 27 %. The study points at a general contamination of aquifers from anthropic origin: phreatic water was already contaminated when pastoralism was dominant (1967); as population increased and irrigation agriculture developed with large use of N-fertilizers and organic amendments, contamination extended spatially and vertically to deep aquifer. To remediate this contamination, fertilizers should be fractionated and limited to plant requirements on the basis of soil and plant analyses. Excess of irrigation should be avoided. Soil surface should be continuously covered to prevent nitrate leaching. Secondly, more efficient irrigation techniques, such as localized irrigation, should be implemented, with adaptation of crop systems and fertilizer inputs to arid conditions. Farmers should then be trained; simultaneously, local agronomic references that are presently lacking should be acquired.     

The creation of a geophysical observatory at the Aleksandrovka research base of the geological faculty of Moscow State University in the Kaluga region

Since May 2011, long-period magnetotelluric (MT) data have been collected in the non-magnetic pavilion at the geophysical base of Moscow University in the Kaluga Region. The non-magnetic pavilion was constructed in compliance with the following conditions: selection of non-magnetic materials, control of local magnetic field anomalies, and setting the basement for magnetometers separately from the main building. Recording equipment with fluxgate and optomechanical magnetometers with three sets of electric lines with different electrodes was installed. The parallel testing of channels was performed. Currently, the seismo-logical equipment and meteorological station are being prepared for installation.     

Satellite-based analysis of the spatial patterns of fire- and storm-related forest disturbances in the Ural region,Russia

Natural Hazards - Large-scale wildfires and windstorms are the most important disturbance agents for the Russian boreal forests. The paper presents an assessment of fire-related and wind-induced...     

Anomalies of the ozone and nitrogen dioxide contents in the stratosphere over Moscow region as a manifestation of the dynamics of the stratospheric polar vortex

Measurements of the stratospheric contents of O₃ and NO₂ in the Moscow region were used to analyze the anomalies of these species related to the sudden stratospheric warming in the winter and the following deformation of the stratospheric circumpolar vortex in early February 2010 and the latitudinal displacement of the vortex towards the European sector in late March 2011 before the final warming in the spring. In the first case, an increase in the O₃ and NO₂ contents up to 85% and by two times, respectively, was recorded. In the second case, the O₃ content decreased by one-fourth and the NO₂ content dropped by two times as compared to the average values for the periods that preceded the beginning of the anomalies.     

Telecommunication computer networks in Moscow

This research note considers the development structure of world-wide computer communications by city territorial divisions, as well as the extent and special factors affecting the use of computer communication services for both providers and consumers. A survey of over 120 Moscow businesses, engaged in a wide range of activities, provided the basis for an analysis of the spread and importance of computer telecommunications systems.     

The economic restructuring of Moscow in the international context

This paper deals with the trends of economic restructuring in Moscow in the 1990s under globalization and reforms. The comparison of structural shifts in Moscow with the largest cities of the West gives an idea about the position of the Russian capital on the trajectory of post-industrial transformation. The analysis covers three dimensions: a) general trends of post-industrial restructuring, b) the role of large cities in national economies, and c) universal and special trends of intra-urban transformation. The reforms of the 1990s initiated many new developments in the economic life of Moscow, making it more similar to the Western cities, both in general sectoral structure and intra-urban landscape. Nevertheless, Moscow still lags far behind the world cities as regards the stage of the most important post-industrial processes. The conflict between new market developments and the inherited patterns of the socialist city becomes one of the driving forces of the economic transformation in Moscow as a whole and in different types of its districts.     

不同人为干扰方式对桂西北喀斯特草丛群落土壤种子库组成与分布的影响

采用野外调查和室内萌发相结合的方法,对桂西北典型喀斯特峰丛洼地刈割、开垦和火烧3种不同人为干扰方式下草丛群落的土壤种子库进行了比较研究。结果表明: ① 3种不同干扰方式草丛群落土壤种子库密度存在显著差异,其种子密度大小为: 刈割群落> 开垦群落> 火烧群落;②刈割、开垦、火烧干扰草丛种子主要分布在0～ 2cm ( 67% )、2～ 5cm ( 55% )、5～ 10cm ( 37% )的土层中;③刈割群落土壤种子库中乔、灌、草生活型的物种比例大于开垦和火烧干扰群落;④ 3种不同干扰方式草丛群落土壤种子库的丰富度指数、Sha nno n-Wie ner 指数和Simpson指数的大小顺序均为: 刈割群落> 开垦群落> 火烧群落,同群落物种数变化趋势一致,与生态优势度呈相反趋势;均匀度指数大小顺序为: 刈割群落> 火烧群落> 开垦群落。⑤从土壤种子库与地面植被物种组成相似性系数来看,刈割群落和开垦群落相似性系数较大,而火烧群落地上与地下物种组成有较大区别,相似性系数为0.296。研究结果表明,刈割干扰相对开垦和火烧更有利于喀斯特地区草丛群落土壤种子库的维持与保护。