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11.
We study several high kinetic energy density jets observed during a traversal of the dayside magnetosheath by the Cluster spacecraft on March 17, 2001, at various distances from the magnetopause, generally characterised by anomalously high values of the local magnetosonic Mach number. We concentrate on two jets observed just outside the magnetopause, the first almost parallel to the GSM x axis and the second directed northward-tailward along the nominal magnetopause surface. We present evidence that none of them can be ascribed to magnetic reconnection at the magnetopause and show that the magnetopause is severely deformed by the jets, so that its local normal forms an angle of 97° with the quiet time magnetopause normal. On these grounds, we suggest that the indentation of the magnetopause is caused by an anti-sunward jet ramming into the magnetopause slightly equatorward of the northern cusp and that the northward-tailward jet is the result of its reflection at the deformed magnetopause. Finally, we briefly discuss our results by comparing them with past studies of events which in some way recall the one analysed herein.  相似文献   
12.
The results of the first stage of the pilot project on the complex monitoring of the atmospheric and ionospheric parameters, conducted on the instructions of the Russian Federation Government in order to decrease risk of destructive earthquakes in the Far East, are presented. The experiment was performed before and during a strong (M = 6.3) earthquake that occurred on August 2, 2007, on Sakhalin. The meteorological data (relative humidity and temperature), cloudiness anomalies according to the TERRA and AQUA satellite data, thermal anomalies of outgoing IR radiation according to the NOAA satellite data, variations in the total electron content according to the GPS data, and tomographic reconstructions of the ionosphere vertical structure according to the TRANSIT satellite data have been analyzed. The indications, typical of earthquake preparation and previously presented in the publications devoted to studying earthquake precursors, have been detected in all analyzed parameters. Synchronism and localization of the anomalies, registered using different methods in different geophysical fields, make it possible to assume that these anomalies have a common source, which could be the earthquake preparation process that is explained using the developed complex model of the lithosphere-atmosphere-ionosphere coupling (LAIC).  相似文献   
13.
The satellite ionosondes in highly elliptical orbits are proposed to be used for the task of continuous monitoring of the Arctic ionosphere. The monitoring scheme with the ionosonde location aboard the Arktika-M satellites is presented. The calculations of the vertical topside and transionospheric sounding using the SIMP1 ionospheric model are performed, which show the feasibility of continuous monitoring.  相似文献   
14.
The Baraba and Kulunda steppes are located in southwestern Siberia in an area with an arid continental climate. This paper presents results of the first study of the hypersaline Lake Krasnovishnevoye(Baraba steppe, TDS(total dissolved solids)=297 g/L, pH 7.88). The major chemical, mineralogical and biological features of the lake were studied and compared to those of Lake Malinovoe, a typical saline neutral lake of Kulunda steppe(TDS=396 g/L, pH 7.63). The phytoplankton composition and the culturable diversity of anoxygenic phototrophic bacteria from Lake Krasnovishnevoye correspond to the ones in the Kulunda lakes. Nevertheless, the peculiarities of water composition and regime of Lake Krasnovishnevoye reduce the biodiversity to prokaryotes and unicellular algae.  相似文献   
15.
On the basis of the experimental data accumulated in 1998–2005, we analyzed the space and time variations of the carbonate system of waters and the content of organic carbon in bottom sediments of the Sevastopol Bay. The intensity of gas exchange through the water-atmosphere interface was quantitatively estimated. It was shown that the partial pressure of carbon dioxide pCO2 in waters of the bay became much higher for the period of observations. The maximum changes were observed in summer. They were especially pronounced for the bottom layer of waters. For the entire period of observations, the invasion of carbon dioxide CO2 was predominant in the major part of the bay, and the content of organic carbon in the bottom sediments increased. The ability of waters in the bay to absorb CO2 is explained by the synthesis of organic substances, which becomes possible due to the presence of the equivalent load of nutrients. __________ Translated from Morskoi Gidrofizicheskii Zhurnal, No. 2, pp. 57–67, March–April, 2008.  相似文献   
16.
Air pollution by industry and motor vehicles, the use of coal ash for the construction of residential and nonresidential buildings, and the presence of dead zones in the residential sector are the main factors of carcinogenic risk to human health. Natural factors (such as topography and prevailing wind directions) can weaken or strengthen technogenic factors. Based on the estimate of pollutant concentrations in the snow cover of Barnaul, we reveal residential areas that are located at the crossroads of atmospheric transport of carcinogenic substances and characterized by concentrations considerably exceeding the maximum allowable concentration. These areas are characterized by the integral accumulation of carcinogenic substances concurrently from multiple sources; for almost any wind rose, the impact of one of the pollution sources is observed throughout the year. The assessment of the carcinogenic risk for a territory depends much on the correlation between local topography and the height of apartments above ground level. Using cancer register data for Barnaul, we reveal an increased level of the incidence of malignant neoplasms in people living in high-rise buildings located in areas with a sharp change in topography (such as ledges, hills, and lowlands). This may occur due to stagnant zones and wind shadows; under certain correlation between topography and the height and shape of buildings, carcinogenic substances accumulate maximally.  相似文献   
17.
The characteristic features of the surface temperature variability in the Northern Hemisphere are studied on the secular time scale. The trends of the temperature anomalies over the continents and oceans were found to be opposite. The present global warming is concluded to be caused by the large-scale redistribution of heat in climatic system, indicating a compensative character of the variations observed. The dynamics of the longitudinal and latitudinal gradients of the surface temperature anomalies were analyzed. It was found that the dynamics of these gradients and the changes in the climate phases on the scales of the Northern Hemisphere are correlated. The present state of the climatic system is discussed, and it is concluded that a change in the climatic scenario in the nearest future is possible.  相似文献   
18.
Doklady Earth Sciences - In the present work, several results of repeated sounding of bottom ice gouging microrelief within the area of the underwater pipeline crossing of the Baydaratskaya Bay,...  相似文献   
19.
The Rwenzori Mountains are a high alpine mountain chain, about 40 × 80 km in size, just north of the equator in the western branch of the East African Rift System in Africa. The central part of the mountain chain is located in Uganda, and the highest peak, the Margherita Peak with 5119 m, lies on the border to the Democratic Republic of Congo. Topography is very pronounced, with steeply incised valleys and clear glacial landforms in the upper part of the mountain chain. The Rwenzori Mountains are an unusually high mountain chain located in the extensional setting of the East African Rift System, and the large elevation poses a challenging problem for geodynamists to explain.We have used the landscape evolution model ULTIMA THULE, which combines hillslope diffusion, fluvial erosion, and glacial abrasion and is driven by a climate driver, simulating the variations in temperature, precipitation, and relief over several glacial cycles. With a simulation time of 800 ka, we test the hypothesis of climate-tectonic interactions on the uplift of the Rwenzori Mountains.Our results show that a moderate cooling of around 6° causes widespread glaciation of the high mountain regions as observed during the peak glacial phases, and that morphological processes degrading the landscape allow for a tectonic uplift rate of around 0.5 mm a− 1.  相似文献   
20.
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