Water Quality Assessment Based on Chemical and Biological Characteristics: An Example of Classification of Characteristics for the Cheremushnyi Creek–Yenisey River Water System

A six-class scale for a complex classifier of water quality is applied to the Cheremushnyi Creek–Yenisey River water system. The classifier incorporates a chemical index of water pollution and biological characteristics with autotrophic and heterotrophic periphyton groups and macrozoobenthos used as biological indicators. The oligochaeta index and Woodiwiss biotic index are shown to have low indicator capacity. Bioassay studies were based on recording acute and chronic toxic effects for three test species at different trophic levels. The level of biologically safe dilution is proposed as a quantitative index of toxicity. Saprobity and toxicity (saprotoxobity) characteristics are given for individual species. Water of the Cheremushnyi Creek–Yenisey River water system is referred to the IV–VI quality class.     

Variations of the Blazar AO 0235+164 in 2006–2015

The results of optical, radio, and gamma-ray observations of the blazar AO 0235+16 are presented, including photometric (BV RIJHK) and polarimetric (R)monitoring carried out at St. Petersburg State University and the Central (Pulkovo) Astronomical Observatory in 2007–2015, 43 GHz Very Long Baseline Interferometry radio observations processed at Boston University, and a gamma-ray light curve based on observationswith the Fermi space observatory are presented. Two strong outbursts were detected. The relative spectral energy distributions of the variable components responsible for the outbursts are determined; these follow power laws, but with different spectral indices. The degree of polarization was high in both outbursts; only an average relationship between the brightness and polarization can be found. There was no time lag between the variations in the optical and gamma-ray, suggesting that the sources of the radiation in the optical and gamma-ray are located in the same region of the jet.     

Effect of Changes in Global Temperature and Radiative Forcing on the General Atmospheric Circulation

Izvestiya, Atmospheric and Oceanic Physics - Possible connections are studied between the monthly average values of the wind angular moment module and the anomaly of the globally averaged surface...     

Plasma magnetosphere of rotating magnetized neutron star in the braneworld

Plasma magnetosphere surrounding rotating magnetized neutron star in the braneworld has been studied. For the simplicity of calculations Goldreich-Julian charge density is analyzed for the aligned neutron star with zero inclination between magnetic field and rotation axis. From the system of Maxwell equations in spacetime of slowly rotating star in braneworld, second-order differential equation for electrostatic potential is derived. Analytical solution of this equation indicates the general relativistic modification of an accelerating electric field and charge density along the open field lines by brane tension. The implication of this effect to the magnetospheric energy loss problem is underlined. It was found that for initially zero potential and field on the surface of a neutron star, the amplitude of the plasma mode created by Goldreich-Julian charge density will increase in the presence of the negative brane charge. Finally we derive the equations of motion of test particles in magnetosphere of slowly rotating star in the braneworld. Then we analyze particle motion in the polar cap and show that brane tension can significantly change conditions for particle acceleration in the polar cap region of the neutron star.     

Landslides triggered by the 1949 Khait earthquake, Tajikistan, and associated loss of life

Earthquake-triggered landslides are a major geological hazard in Central Asia. In July 1949, the M7.4 Khait earthquake triggered many hundreds of landslides in a mountainous region near the southern limit of the Tien Shan Mountains, central Tajikistan. These landslides involved widespread rock-slope failure as well as large numbers of flowslides in loess that mantles the steep slopes of the region. In the Yasman valley hundreds of loess landslides coalesced to form a massive loess flow (est. vol. 245 Mm³) that travelled up to 20 km on a slope of only 2°. In an adjacent valley, the Khait landslide involved transformation of an earthquake-triggered rockslide into a very rapid flow by the entrainment of saturated loess into its movement. It travelled 7.41 km over a vertical distance of 1421 m with an estimated average velocity of ~30 m/s. We estimate its volume as 75 Mm³, an order of magnitude less that previously published estimates. The Khait landslide was simulated using DAN. The number of casualties due to earthquake-triggered landslides in the epicentral region was considerable. Approximately 4000 people were killed in the Yasman valley loess flow as 20 villages (kishlaks) were overwhelmed. In the Khait landslide alone we estimate ca. 800 people lost their lives when the villages of Khait and Khisorak were overrun by rapidly moving debris. Our data indicates that a total of approximately 7200 people were killed by earthquake-triggered landslides in the epicentral region of the Khait earthquake and that, in terms of loss of life, the 1949 Yasman valley loess flow was one of the most destructive landslides in recent history.     

Reconstruction of Climate of the Eemian Interglacial Using an Earth System Model. Part 2. The Response of the Greenland Ice Sheet to Climate Change

In the framework of the study of the Eemian interglacial we consider the role of the Greenland ice sheet in the rise of the mean level of the World Ocean. Its contribution estimated as 2 m confirms the newest estimates based on the model results and on the proxy data analysis. In the beginning of the Eemian interglacial (earlier than 126 thousand years ago) mass lost occurs through the marine margin of the sheet. During the next five millennia, the negative surface mass balance plays the leading role. Taking into account the contribution of Greenland ice sheet, ocean thermal expansion, and the melting of mountain glaciers and ice caps, it is very probable that the West Antarctic ice sheet was the main source of the global sea level growth equal to 6–9 m the compared to the present.     

Water Budget of the Caspian Sea in the Last Glacial Maximum by Data of Experiments with Mathematical Models

Water Resources - Variations of Caspian Sea water budget in the epoch of the Last Glacial Maximum (LGM, ~21 thousand years ago) relative to the preindustrial conditions (~1850 CE) are considered...     

Relating 27-Day Averages of Solar,Interplanetary Medium Parameters,and Geomagnetic Activity Proxies in Solar Cycle 24

Solar Physics - During solar minimum, the Sun is relatively inactive with few sunspots observed on the solar surface. Consequently, we observe a smaller number of highly energetic events such as...     

Suspended matter in the estuaries of the Guinean shelf

The paper discusses the data on distribution and composition of suspended matter in Guinea’s coastal zone (Tonkima and Tabunsu river estuaries) during November–December 1990. Tidal events, bottom topography and coast-line configuration are shown to influence sediments’ biochemical composition and distribution. The content of the organic carbon, nitrogen, total phosphate and chlorophyll in the particulate organic matter has been determined. Translated by Vladimir A. Puchkin.     

Comparison of Borehole Geoacoustic and Electromagnetic Data with Data of Earthquake Focal Mechanisms

Doklady Earth Sciences - The results of comparing the data of two methods of geophysical monitoring of the stress-strain state of a borehole of the geoenvironment in the zone of...