Groundwater Hydrochemistry of Suprapermafrost–Intrapermafrost Flow in Their Discharge Areas in Central Yakutia

Water Resources - The results of long-term studies of a group of aufeis-forming Buluus groundwater sources are given. A stow, which has been formed by the spring, contains the drainage area of the...     

Increase of brightness and radiation temperature in a non-inverted medium: does this work in astrophysical masers?

The general conditions for the increase of brightness and radiation temperature are discussed. It is shown that such an increase is possible in a non-inverted medium, and perhaps actually takes place even in some cases of bright hydroxyl sources, which are usually treated as masers.     

The structure of the radio galaxy 3C388 at decameter wavelengths

Observations of the structure of the radio galaxy 3C338 at decameter wavelengths obtained using the URAN-1 and URAN-2 radio interferometers are presented. The structure of this object at these wavelengths differs appreciably from images obtained at higher frequencies. The most probable simple models for the radio brightness distributions at 25 and 20 MHz are determined: two extended components with sizes from 40″ to 50″ whose centers are separated by 90″–100″ in position angle about 100°, and a single compact component 9″×4″ in size, whose flux density does not exceed 10% of the total flux density of the radio galaxy.     

Interferometric Observations of the Quiet Sun at 20 and 25 MHz in May 2014

We present the results of solar observations at 20 and 25 MHz with the Ukrainian T-shaped Radio telescope of the second modification (UTR-2) in the interferometric session from 27 May to 2 June 2014. In this case, the different baselines 225, 450, and 675 m between the sections of the east–west and north–south arms of UTR-2 were used. On 29 May 2014, strong sporadic radio emission consisting of Type III, Type II, and Type IV bursts was observed. On other days, there was no solar radio activity in the decameter range. We discuss the observation results of the quiet Sun. Fluxes and sizes of the Sun in east–west and north–south directions were measured. The average fluxes were 1050?–?1100 Jy and 1480?–?1570 Jy at 20 and 25 MHz, respectively. The angular sizes of the quiet Sun in equatorial and polar directions were \(55'\) and \(49'\) at 20 MHz and \(50'\) and \(42'\) at 25 MHz. The brightness temperatures of the radio emission were \({T_{\mathrm{b}}} = 5.1 \times{10^{5}}~\mbox{K}\) and \({T_{\mathrm{b}}} = 5.7 \times{10^{5}}~\mbox{K}\) at 20 and 25 MHz, respectively.     

An investigation of the Cassiopeia A radio-image in the decameter range

The observation results of the supernova remnant Cassiopeia A, obtained with the aid of two decameter radio interferometers at 20 and 25 MHz, are presented. The so obtained dependences of the visibility function modulus on the hour angle are compared with calculations based on the brightness distribution measurements of this source using the VLA at 1381 MHz. Discrepancies between the experimental data and the calculations considerably increase with the decrease in the frequency. It is suggested that interstellar medium absorption, causing a distortion in the source spectrum over the decameter range, may be responsible for changes in the Cas A brightness distribution at these frequencies as well.     

Spatial and Temporal Dynamics of Sources and Water Regime of the Ugol’naya-Dionisiya River (Anadyr Lowland,Chukotka)

Water Resources - For the first time, by analyzing the spatial variations and diurnal dynamics of the water regime of the small river of the Anadyr Lowland, the main sources were studied and the...     

Extended component in the quasar 3C 380

Results of radio interferometric observations of the quasar 3C 380 carried out on the URAN interferometers at decameter wavelengths and on the aperture synthesis radio telescope VLA at meter wavelengths are reported. The spectral index of an extended lobe about 10″ in size is considerably lower than at decimeter wavelengths. Below ～ 100 MHz, the ratio of the emission from the compact components associated with hot spots in the radio lobe to the total flux of the source decreases due to synchrotron self-absorption at hot spots, whose flux density at 20 MHz does not exceed 65 Jy. A halo with a full width at a half-maximum of about 40″ was detected, whose angular extent considerably exceeds the total source size measured at shorter wavelengths.     

Comparison of ground-based and satellite measurements of total ozone

Presented are the results of studies dealing with the analysis of discrepancies in the data on total ozone measurements carried out using different instruments. The results of measurements with ground-based spectral (UV and visible) and filter instruments and spaceborne nadir scanning instruments are used as initial data. As a result of the analysis of relative systematic and random discrepancies, it is concluded that the data of filter instruments are of insufficient accuracy for diagnosing total ozone values. The analysis of linear trends revealed the presence of considerable differences in the data series obtained by spectral instruments. It is concluded that there is every reason to hope for obtaining the most homogeneous measurement data in Russia using the instruments operating in the Chappuis band.     

Suprapermafrost waters of the cryolithosphere and their classification

A classification scheme for suprapermafrost waters is suggested, which was developed by this author. Under this scheme, the suprapermafrost waters are divided, according to the conditions of their occurrence, into three main subtypes: suprapermafrost vadose water, waters of the seasonally thawed layer, and suprapermafrost groundwater. The subtypes and kinds of suprapermafrost waters identified in this study are briefly outlined.     

On the Cycle of Natural Waters

The role of the phase transition and interphase transfer of water in its circulation are considered and accounted for in the proposed unified scheme of the natural water cycle. Four types of water-exchange cycles are singled out, and each of these is subdivided into particular subcycles. The calculated energy characteristics of some subcycles testify to a great effect of the subcycles associated with the water phase transitions on the formation of the earth's heat balance, the planetary gas exchange, and other global processes.