Distribution and diversity of microbial communities in meromictic soda Lake Doroninskoe (Transbaikalia,Russia) during winter

Meromictic soda and saline lakes are unique ecosystems characterized by the stability of physical,chemical and biological parameters,and they are distributed all over the world.Lakes located in regions with average annual negative air temperature are of particular interest because of the presence of two periods with intensive and dynamic processes:the so-called biological summer and the long ice season with the biological spring.Soda Lake Doroninskoe is located in Eastern Transbaikalia(51°14′N,112°14′E) in the permafrost zone in an extreme continental climate,and is covered by ice for seven months per year.The structure and diversity of the microbial communities throughout the water column of the lake was studied by 16 S r RNA gene amplicon metasequencing.Different species with specific functions were found to dominate at different depths.Metabolically flexible bacteria with a capacity to switch between anoxygenic photosynthesis and aerobic chemotrophic metabolism dominate in soda Lake Doroninskoe.     

Characterizing proteases in an Antarctic Janthinobacterium sp. isolate：Evidence of a protease horizontal gene transfer event

We report the isolation of a cold-adapted bacterium belonging to the genus Janthinobacterium (named AU11), from a water sample collected in Lake Uruguay (King George Island, South Shetlands). AU11 (gro...     

Discovering Landmark Preferences and Movement Patterns from Photo Postings

This article presents a geovisual analytics approach to discovering people's preferences for landmarks and movement patterns from photos posted on the Flickr website. The approach combines an exploratory spatio‐temporal analysis of geographic coordinates and dates representing locations and time of taking photos with basic thematic information available through the Google Maps Web mapping service, and interpretation of the analyzed area. The article describes data aggregation and filtering techniques to reduce the size of the dataset and focuses on information addressing research questions. The results of analysis for the Seattle metropolitan area help to distinguish between sites that are occasionally popular among the photographers and can be considered as potential attractions from sites that are regularly visited and already known as city landmarks. The analysis of photographers' movements across the metropolitan area shows that most photographers' itineraries are short and highly localized.     

ULF wave indices to characterize the solar wind-magnetosphere interaction and relativistic electron dynamics

To quantify the level of low-frequency wave activity of the magnetosphere and IMF, a set of the ULF wave power indices has been introduced. We demonstrate that the ULF activity global level can be very useful in space weather related problems. The application of the interplanetary index to an analysis of auroral activity driving has shown that a turbulent IMF drives auroral activity more strongly than the laminar solar wind does. The enhancements of relativistic electrons at the geosynchronous orbit are known not to be directly related to the intensity of magnetic storms. We found that the electron dynamics correlated well with long-lasting intervals of elevated ground ULF wave index. This fact confirms the importance of magnetospheric ULF turbulence in energizing electrons up to relativistic energies. The time-integrated ULF index demonstrates a significantly higher correlation with electron fluxes, which implies the occurrence of a cumulative effect in the electron energization.     

Strong tidal currents over two shallow banks in the western subarctic Pacific

The south-flowing waters of the Kamchatka and Oyashio currents are key components of the western subarctic Pacific gyre. The dissipation of tidal energy in shallow and coastal regions of these currents and the attendant mixing are the important processes that affect the upper layer temperature and salinity. Examples of the impact of tidal currents on water temperature and salinity are the persistent tide-driven mixing around the Kashevarov and Kruzenshtern banks. The Kruzenshtern Bank is a shallow submarine bank stretching along the eastern continental slope of the Kuril Islands with the minimum depth of 86 m. Surface drifters observations are used to determine the characteristics of tidal currents and the circulation over these banks. New software that allows more versatility in the harmonic analysis is used for drifter’s data. The two banks have similar features. The variations in current velocities are dominated by the diurnal signals. The K₁ and O₁ tidal ellipses over the banks are the largest and clockwise. The enhanced tidal currents suggest that the formation of cold and saline water in summer is due to mixing of water column over the banks with intermediate waters. Variations of tidal ellipses over the bank may explain the formation of polynya at the western end of the Kashevarov Bank. We found that the 18.6-year lunar nodal cycle is a significant characteristic of salinity variation at the temperature minimum in the eddies eastward of the Boussole Strait over the period 1990–2015.     

Experimental shock metamorphism of terrestrial basalts: Agglutinate-like particle formation,petrology, and magnetism

Hypervelocity impacts occur on bodies throughout our solar system, and play an important role in altering the mineralogy, texture, and magnetic properties in target rocks at nanometer to planetary scales. Here we present the results of hypervelocity impact experiments conducted using a two-stage light-gas gun with 5 mm spherical copper projectiles accelerated toward basalt targets with ~6 km s⁻¹ impact velocities. Four different types of magnetite- and titanomagnetite-bearing basalts were used as targets for seven independent experiments. These laboratory impacts resulted in the formation of agglutinate-like particles similar in texture to lunar agglutinates, which are an important fraction of lunar soil. Materials recovered from the impacts were examined using a suite of complementary techniques, including optical and scanning electron microscopy, micro-Raman spectroscopy, and high- and low-temperature magnetometry, to investigate the texture, chemistry, and magnetic properties of newly formed agglutinate-like particles and were compared to unshocked basaltic parent materials. The use of Cu-projectiles, rather than Fe- and Ni-projectiles, avoids magnetic contamination in the final shock products and enables a clearer view of the magnetic properties of impact-generated agglutinates. Agglutinate-like particles show shock features, such as melting and planar deformation features, and demonstrate shock-induced magnetic hardening (two- to seven-fold increases in the coercivity of remanence B_cr compared to the initial target materials) and decreases in low-field magnetic susceptibility and saturation magnetization.     

The Impacts of Climate Variability on Near-Term Policy Choices and the Value of Information

Variability is one of the most salient features of the earth's climate, yet quantitative policy studies have generally ignored the impact of variability on society's best choice of climate-change policy. This omission is troubling because an adaptive emissions-reduction strategy, one that adjusts abatement rates over time based on observations of damages and abatement costs, should perform much better against extreme uncertainty than static, best-estimate policies. However, climate variability can strongly affect the success of adaptive-abatement strategies by masking adverse trends or fooling society into taking too strong an action. This study compares the performance of a wide variety of adaptive greenhouse-gas-abatement strategies against a broad range of plausible future climate-change scenarios. We find that: i) adaptive strategies remain preferable to static, best-estimate policies even with very large levels of climate variability; ii) the most robust strategies are innovation sensitive, that is, adjust future emissions reduction rates on the basis of small changes in observed abatement costs but only for large changes in observed damages; and iii) information about the size of the variability is about a third to an eighth as valuable as information determining the value of the key parameters that represent the long-term, future climate-change state-of-the-world.     

Country-Specific Market Impacts of Climate Change

We develop a new climate-impact model, theGlobal Impact Model (GIM), which combines futurescenarios, detailed spatial simulations by generalcirculation models (GCMs), sectoral features,climate-response functions, and adaptation to generatecountry-specific impacts by market sector. Estimatesare made for three future scenarios, two GCMs, andtwo climate-response functions – a reduced-form modeland a cross-sectional model. Combining empiricallybased response functions, sectoral data by country,and careful climate forecasts gives analysts a morepowerful tool for estimating market impacts. GIMpredicts that country specific results vary, implyingthat research in this area is likely to bepolicy-relevant.