Geologic structure and correlation of the Berriasian-Lower Aptian productive beds of the Gydan Peninsula (Russian Arctic)

We discuss the geologic structure of the Berriasian-Lower Aptian deposits of the Gydan Peninsula. Eight seismic sequences have been distinguished; most of them are associated with Lower Cretaceous regional clinoforms of West Siberia, their characteristics are given. A correlation of productive beds was based on the stratotype sections of the Yamal and Gydan Peninsulas as well as seismic and well data. A sequence stratigraphic model of the Berriasian-Lower Aptian complex is proposed.     

Influence of Biogenous Elements on Components of the Lake Baikal Plankton Community

Fertilization experiments in mesocosms of 1 … 2,000 1 containing up to 0.32 mg/l P and 1.7 mg/l N in summer and in winter did not show any significant changes of the hydrochemical conditions and in the bacterio-plankton. CO₂-assimilation (14-C method) is reduced by circa 10= by nutrient doses, whereas the chlorophyll concentration increases significantly due to addition of P and N at the same time in summer, a decrease taking place in winter. The different courses of development are connected with different reactions of individual species of phytoplankton.     

Experience of Studying the Turbulent Structure of the Atmospheric Boundary Layer Using an Unmanned Aerial Vehicle

Izvestiya, Atmospheric and Oceanic Physics - The growing relevance of the use of unmanned aerial vehicles (UAVs) for studying turbulence in the atmospheric boundary layer (ABL) is associated with...     

Observations of the dust radial velocity field in the F-corona on March 29, 2006

The results of interferometer observations of the dust radial velocity field in the F-corona during the total solar eclipse of March 29, 2006, are presented. The observations were performed in the Mugalzhar settlement, Aqtobe region, Kazakhstan. The observation results indicated that the dust orbital motion is opposite to the planetary motion and is inclined at an angle of about 105° with respect to the ecliptic plane. It is assumed that the observed dust is genetically related to Kreutz comets falling on the Sun and registered with the SOHO spacecraft on March 28 and 31, 2006.     

Numerical simulation of storm waves near the northeastern coast of the Black Sea

The results ofnumerical simulation of storm waves near the northeastern coast ofthe Black Sea using different wind forcing (CFSR reanalysis, GFS forecast, and WRF reanalysis and forecast) are presented. The wave modeling is based on the SWAN spectral wave model and the high-resolution unstructured grid for the Tsemes Bay. The quality estimates of wave simulation results for various wind forcing are provided by comparing the model results with the instrumental data on wind waves in the Tsemes Bay. It is shown that the forecast of the maximum wave height for some storms using the WRF wind forcing is more accurate than that based on the GFS forcing.     

The impact of radar data assimilation on atmosphere state analysis in the Moscow region

The results of numerical experiments with the data assimilation system including the WRF-ARW mesoscale atmospheric model and WRFDA analysis package in the 3D-Var mode are considered. The focus is on the impact of Doppler weather radar data on the quality of short-range weather forecasting. The maps of weather events and cloud top constructed from the modeling by GIMET-2010 software package are analyzed using the web-GIS METEORAD. The experiments in the Moscow region demonstrated that if only radial wind is assimilated, the intensity of simulated cloud and precipitation formation is the closest to the observed one; however, the spatial mismatches of simulated and observed cloud systems are possible. If Doppler radar data on radial wind and reflectivity are assimilated, the general pattern and location of clouds and precipitation are simulated more accurately, but there is a certain overestimation of convection intensity which leads to the overestimation of the number of thunderstorms and rainfall rate.     

Interferometric observations of the H II region around ξ Per

A Fabry-Perot spectrometer was used to map the H II region around the O star ξ Per in the Hβ emission line. The angular size of the region is \(9_.^ \circ 1 \times 6_.^ \circ 0\). The region-boundary contour drawn at the double background level is centered on the star. The accuracy of our emission intensity measurements is 0.2 rayleigh. The proximity of the nebula NGC 1499 has virtually no effect on the measured emission measure toward the star. The star excitation parameter derived from observations corresponds to the spectral type O7.5 III and is U(Sp)=56.0±8.4 pc cm^?2; the mean electron density in the region is n_e=3.1±0.4 cm^?3.     

Microelements Speciations in Bottom Sediments of Udomlya and Pes’vo Lakes

Water Resources - Microelements in bottom sediments may enter different compounds; however, of greatest interest are their mobile forms as the most bioavailable. The microelements speciation in the...     

Orbital Evolution of Dust Particles in the Sublimation Zone near the Sun

We have performed the calculations of the orbital evolution of dust particles from volcanic glass (p-obsidian), basalt, astrosilicate, olivine, and pyroxene in the sublimation zone near the Sun. The sublimation (evaporation) rate is determined by the temperature of dust particles depending on their radius, material, and distance to the Sun. All practically important parameters that characterize the interaction of spherical dust particles with the radiation are calculated using the Mie theory. The influence of radiation and solar wind pressure, as well as the Poynting–Robertson drag force effects on the dust dynamics, are also taken into account. According to the observations (Shestakova and Demchenko, 2016), the boundary of the dust-free zone is 7.0–7.6 solar radii for standard particles of the zodiacal cloud and 9.1–9.2 solar radii for cometary particles. The closest agreement is obtained for basalt particles and certain kinds of olivine, pyroxene, and volcanic glass.