Analysis of the effect of megalopolises on water quality in surface water bodies by ecological-toxicological characteristics

Data of long-term observations of Roshydromet and the studies of the authors’ studies of hydrochemical, hydrobiological, and bioassaying characteristics and appropriate publications in the areas of megalopolises—the cities of Rostov-on-Don and Novosibirsk are analyzed. Similar and distinctive characteristics of water quality by these ecological-toxicological characteristics are identified; trends in the long-term year-to-year variations in water quality are established, criteria and characteristics reflecting the effect of cities on water bodies in their territory are determined. The identity of some chemical-toxicological criteria and the characteristics of the influence of cities in southern Russia and Siberia on water bodies suggest that they can also be used in urban area in other regions. The Lower Don is used as an example to show that water pollution by metals is mostly due to wastewater discharge, while water pollution by petroleum products and sulfates has no direct relation to that.     

Lava tube shatter rings and their correlation with lava flux increases at Kīlauea Volcano,Hawai‘i

Shatter rings are circular to elliptical volcanic features, typically tens of meters in diameter, which form over active lava tubes. They are typified by an upraised rim of blocky rubble and a central depression. Prior to this study, shatter rings had not been observed forming, and, thus, were interpreted in many ways. This paper describes the process of formation for shatter rings observed at Kīlauea Volcano during November 2005–July 2006. During this period, tilt data, time-lapse images, and field observations showed that episodic tilt changes at the nearby Pu‘u ‘Ō‘ō cone, the shallow magmatic source reservoir, were directly related to fluctuations in the level of lava in the active lava tube, with periods of deflation at Pu‘u ‘Ō‘ō correlating with increases in the level of the lava stream surface. Increases in lava level are interpreted as increases in lava flux, and were coincident with lava breakouts from shatter rings constructed over the lava tube. The repetitive behavior of the lava flux changes, inferred from the nearly continuous tilt oscillations, suggests that shatter rings form from the repeated rise and fall of a portion of a lava tube roof. The locations of shatter rings along the active lava tube suggest that they form where there is an abrupt decrease in flow velocity through the tube, e.g., large increase in tube width, abrupt decrease in tube slope, and (or) sudden change in tube direction. To conserve volume, this necessitates an abrupt increase in lava stream depth and causes over-pressurization of the tube. More than a hundred shatter rings have been identified on volcanoes on Hawai‘i and Maui, and dozens have been reported from basaltic lava fields in Iceland, Australia, Italy, Samoa, and the mainland United States. A quick study of other basaltic lava fields worldwide, using freely available satellite imagery, suggests that they might be even more common than previously thought. If so, this confirms that episodic fluctuation in lava effusion rate is a relatively common process at basaltic volcanoes, and that the presence of shatter rings in prehistoric lava flow fields can be used as evidence that such fluctuations have occurred.     

Evaluation of stratospheric ozone,temperature, and aerosol profiles from the LOANA lidar in Antarctica

We present an evaluation of observations from the Lidar Ozone and Aerosol for NDACC in Antarctica (LOANA) at the Dumont d’Urville station, Antarctica. This instrument is part of the Network for the Detection of Atmospheric Composition Change (NDACC), and ensures continuity with lidar measurements made since 1989 with the previous instrument at this site. This study is based on the dataset from 2008 to 2009, and comparisons are made with observations from balloon soundings, and from three satellite experiments: Aura/MLS, TIMED/SABER, and CALIOP/CALIPSO. The lidar ozone data are in very good agreement with the balloon sounding data (ECC sensor), revealing a bias of less than 3% between 17 and 34 km. For temperature, the lidar shows a low bias of ?3 K at 20 km when compared with Aura/MLS. Between 30 and 50 km, the bias is less than 2 K. We also present our initial results showing diurnal variations in temperature. The amplitude of these diurnal cycles is on the order of 1 K and is unlikely to account for the temperature biases between LOANA and the reference instruments. Comparisons of total attenuated backscatter reveal good qualitative agreement between LOANA and CALIOP, with differences of less than 30% in the derived optical depth.     

Large-Scale Atmospheric–Oceanic Interaction Regimes in the Norwegian and Barents Seas

Doklady Earth Sciences - Large-scale atmosphere–ocean interaction in the Atlantic sector of the Arctic Ocean is analyzed. New studies demonstrate that the variability of Atlantic water inflow...     

Comparison Analysis of Recognition Algorithms of Forest-Cover Objects on Hyperspectral Air-Borne and Space-Borne Images

Izvestiya, Atmospheric and Oceanic Physics - The basic model for the recognition of natural and anthropogenic objects using their spectral and textural features is described in the problem of...     

Investigation of dynamic response of masonry minaret structures

Almost all historical minarets in Turkey were constructed using cut stone, masonry blocks or combination of these two materials. The structural and geometrical properties of each masonry minaret, or slender tower structure, depend on many factors including the structural knowledge and applications at the time of construction, experience of the architect or engineer, seismicity of the region, and availability of construction materials in that area. Recent earthquakes in Turkey have shown that most masonry minarets in high seismic regions are vulnerable to structural damage and collapse. In this study, in order to investigate the dynamic behavior of historical unreinforced masonry minarets, three representative minarets with 20, 25, and 30 m height were modeled and analyzed using two ground motions recorded during the 1999 Kocaeli and Duzce, Turkey earthquakes. The modal analyses of the models have shown that the structural periods and the overall structural response are influenced by the minaret height and spectral characteristics of the input motion. The dynamic displacement and axial stress time histories are computed at the critical points on the minarets. During recent earthquakes, most minaret failures occurred above the base of the structure. Consistent with the observed response, the largest stresses were calculated at the same location.