On the processes of mass transport in rotating gas-dust clouds

A model of motion of gaseous matter flowing into a rotating gas-dust cloud from a central body is considered. The authors suggest an equation of matter transport and the boundary conditions for a number of cases, and also deduce relations governing the variations of concentration of the flowing matter particles in the pre-planetary gas-dust cloud, depending on distance and time. It is demonstrated that the motion of matter in rotating gas-dust clouds is governed by the classical law of mass transfer.The results obtained confirm a physico-chemical hypothesis about the formation of the planetary systems which was suggested earlier, and which is based on diffusion mechanisms of the appearance of the primary rings of the condensed matter, the rings later becoming accumulated into planets and satellites.     

Variation Trend and Characteristics of Anthropogenic CO Column Content in the Atmosphere over Beijing and Moscow

The anthropogenic CO column content in the atmosphere is derived from measurements with infrared grating spectrometers in Beijing, China, and Moscow, Russia, during 1992-2012. Some specific variation char- acteristics and long-term variation trends of the CO col- umn content in the atmosphere in these regions are dis- cussed. An evident variation trend of anthropogenic CO in the atmosphere for the Beijing region is not observed during 1992-2012, while for the Moscow region, it de- creases yearly by about 1.4% for the same period. High CO concentrations appear quite frequently in Beijing, but much less frequently in Moscow, except during the natu- ral fire events in summer 2010. From back trajectory analysis, the high CO concentration observed in Beijing can be attributed to the intensive CO emission sources in its surrounding areas.     

Average annual structure and transport of waters eastward of Greenland by the system of western boundary currents

The results of calculating the values of average annual transport of waters eastward of Greenland in 2007–2015 by the system of western boundary currents are discussed. It is shown that the values of the average annual transport of waters estimated by different methods for measuring the velocity of currents and the different calculation methods differ by 20%. The role of friction in the bottom jets of the northwestern deep water, which were discovered for the first time during long-term observations, is discussed. The considerable contribution of the shelf water cascading across the continental slope to the formation of the structure and transport of the East Greenland Current is established. The significant influence of vertical mixing on the physicochemical properties of the bottom layer waters is shown. The biological arguments of the contribution made by the Irminger current and the subsurface waters to the formation of the northwestern deep water are presented.     

Spatial Variability of Phytoplankton Primary Production Characteristics in the North Atlantic in Summer 2013

Oceanology - The spatial variability of phytoplankton primary production characteristics has been studied along transects between the Shetland Islands and Iceland (transect I) and along 59.5°...     

Distribution and migration of metals in trophic chains of the Yenisei ecosystem near Krasnoyarsk City

Methods of atomic absorption, flame photometry, and emission spectral analysis were used to study the concentrations of metals in water and major ecosystem components of the Yenisei River upstream of Krasnoyarsk City (conventionally background area). The mean bulk concentrations of Al and Cu in water exceeded the MAC for water bodies used for fishery. Cu concentration in freshwater shrimp was found to be reliably higher than that in the link of primary producers (periphyton), and Cd concentration in caddis fly larvae was found to exceed that in water moss. The maximal concentrations of metals among the examined aquatic organisms were recorded in periphyton. Cr concentration in the muscles of Arctic grayling was found to exceed some international standards.     

Currents in the drake passage based on the observations in November of 2010

The currents in the central part of the Drake Passage are investigated by analyzing the CTD and SADCP data over the section across the Drake Passage occupied in November 2010 and satellite altimetry data. All eight of the jets of the Antarctic Circumpolar Current, which are currently identidifed, were resolved by the section. The velocities and water transports of these jets are estimated. Three synoptic scale eddies with different vertical structures were revealed; hypotheses on the physical nature of these eddies are discussed.     

KMAH index and separation of PSP-waves from streamer data

The presence of triplications (caustics) can be a serious problem in seismic data processing and analysis. The travel-time curve becomes multi-valued and the geometrical spreading correction factor tends to zero due to energy focusing. To select the regions of possible triplications (caustics) of travel-times, which can arise during the propagation of reflected seismic waves, we use the Keller–Maslov–Arnol’d-Hörmander (KMAH) index. The identification of such regions improves the selection of signals associated with target reflecting horizons and their use in solving various inverse dynamic problems, including amplitude-versus-offset (AVO) and full-waveform inversions. The importance of the KMAH index increases in 4D surveys when the structure of the model is already known, and it is necessary to conduct a detailed analysis of the shapes of seismic signals with increasing accuracy when solving inverse seismic problems. In addition, this index can be valuable when solving various marine seismic problems associated with single and converted waves, in particular with PSP-waves. The present work is dedicated to the separation of signals associated with this type of wave using surface marine seismic data. However, the proposed algorithm has a wider application. It is based on: (i) a priori information on the medium under study; (ii) ray tracing method. The ray tracing method enables the identification of the corresponding signals and the determination of the time and space intervals, in which such signals are most accurately traced. These intervals are used in the selection of target signals, particularly signals related to PSP-waves. In order to select optimal areas of observation with higher amplitudes of target signals, we use the \(\tau -p\) transform. To improve the stability of the signal separation, KMAH index is used. This approach allows the elimination of possible triplications (caustics) in the travel-time curve from the selected intervals.