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https://www.readbyqxmd.com/read/28448809/recent-land-use-and-land-cover-changes-and-its-driving-factors-in-a-fire-prone-area-of-southwestern-turkey
#1
Olga Viedma, José M Moreno, Cumhur Güngöroglu, Ufuk Cosgun, Ali Kavgacı
During the last decades, contrasted trends in forest fires among countries around the Mediterranean basin have been observed. In the northern/western countries, Land Use-Land Cover (LULC) changes led to more hazardous landscapes, with consequent increases in fires. This contrasted with fire trends in southern/eastern countries. The recent incidence of large fires in some of the latter prompted the question of whether they are now following the path of their neighbors decades earlier. In this study, we investigated recent LULC changes in southwestern Turkey, focusing on those that could affect fire, and the factors driving them...
April 24, 2017: Journal of Environmental Management
https://www.readbyqxmd.com/read/28442237/long-term-ert-monitoring-of-biogeochemical-changes-of-an-aged-hydrocarbon-contamination
#2
David Caterina, Adrian Flores Orozco, Frédéric Nguyen
Adequate management of contaminated sites requires information with improved spatio-temporal resolution, in particular to assess bio-geochemical processes, such as the transformation and degradation of contaminants, precipitation of minerals or changes in groundwater geochemistry occurring during and after remediation procedures. Electrical Resistivity Tomography (ERT), a geophysical method sensitive to pore-fluid and pore-geometry properties, permits to gain quasi-continuous information about subsurface properties in real-time and has been consequently widely used for the characterization of hydrocarbon-impacted sediments...
April 10, 2017: Journal of Contaminant Hydrology
https://www.readbyqxmd.com/read/28434821/an-overview-of-geophysical-technologies-appropriate-for-characterization-and-monitoring-at-fractured-rock-sites
#3
Frederick D Day-Lewis, Lee D Slater, Judy Robinson, Carole D Johnson, Neil Terry, Dale Werkema
Geophysical methods are used increasingly for characterization and monitoring at remediation sites in fractured-rock aquifers. The complex heterogeneity of fractured rock poses enormous challenges to groundwater remediation professionals, and new methods are needed to cost-effectively infer fracture and fracture-zone locations, orientations and properties, and to develop conceptual site models for flow and transport. Despite the potential of geophysical methods to "see" between boreholes, two issues have impeded the adoption of geophysical methods by remediation professionals...
April 20, 2017: Journal of Environmental Management
https://www.readbyqxmd.com/read/28422184/sea-level-proxies-in-holocene-raised-beach-ridge-deposits-greenland-revealed-by-ground-penetrating-radar
#4
Lars Nielsen, Mette Bendixen, Aart Kroon, Mikkel Ulfeldt Hede, Lars B Clemmensen, Ronny Weβling, Bo Elberling
Identification of sea-level proxies is important for reconstruction of past sea-level variation. Methods for reconstructing Holocene relative sea-level curves are crucial for quantification of the impact of Greenland ice thickness variation on global sea level and vertical land movement. Arctic beach ridges constitute important potential archives of sea-level variation. However, their surface morphology may have undergone modification since deposition due to freezing/thawing processes and erosion, and their morphology may therefore not be trustworthy for sea-level reconstruction...
April 19, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28417925/a-cost-effective-geodetic-strainmeter-based-on-dual-coaxial-cable-bragg-gratings
#5
Jihua Fu, Xu Wang, Tao Wei, Meng Wei, Yang Shen
Observations of surface deformation are essential for understanding a wide range of geophysical problems, including earthquakes, volcanoes, landslides, and glaciers. Current geodetic technologies, such as global positioning system (GPS), interferometric synthetic aperture radar (InSAR), borehole and laser strainmeters, are costly and limited in their temporal or spatial resolutions. Here we present a new type of strainmeters based on the coaxial cable Bragg grating (CCBG) sensing technology that provides cost-effective strain measurements...
April 12, 2017: Sensors
https://www.readbyqxmd.com/read/28413357/introduction-for-perspectives-in-geophysical-and-astrophysical-fluids
#6
EDITORIAL
Steven Tobias
No abstract text is available yet for this article.
March 2017: Proceedings. Mathematical, Physical, and Engineering Sciences
https://www.readbyqxmd.com/read/28413355/a-computational-continuum-model-of-poroelastic-beds
#7
U Lācis, G A Zampogna, S Bagheri
Despite the ubiquity of fluid flows interacting with porous and elastic materials, we lack a validated non-empirical macroscale method for characterizing the flow over and through a poroelastic medium. We propose a computational tool to describe such configurations by deriving and validating a continuum model for the poroelastic bed and its interface with the above free fluid. We show that, using stress continuity condition and slip velocity condition at the interface, the effective model captures the effects of small changes in the microstructure anisotropy correctly and predicts the overall behaviour in a physically consistent and controllable manner...
March 2017: Proceedings. Mathematical, Physical, and Engineering Sciences
https://www.readbyqxmd.com/read/28405963/multidimensional-investigation-of-bedrock-heterogeneity-unconformities-at-a-dnapl-impacted-site
#8
Colby M Steelman, Jessica R Meyer, Beth L Parker
Organic solvent (i.e., dense nonaqueous phase liquid, DNAPL) migration in the subsurface is known to be extremely sensitive to geologic heterogeneity. There is often a focus on heterogeneity that results from changing depositional conditions over short spatial scales. Similar or even more extreme spatial heterogeneity can result postdeposition due to erosional processes. This study applies a synergistic approach based on a combination of high-resolution lithologic logs of continuous cores, borehole geophysical logs, surface electrical resistivity, and seismic refraction tomography models to assess spatial heterogeneity in a shallow bedrock sequence subject to multiple unconformities and contaminated with a mixture of organic chemicals...
April 12, 2017: Ground Water
https://www.readbyqxmd.com/read/28386482/long-term-global-temperature-variations-under-total-solar-irradiance-cosmic-rays-and-volcanic-activity
#9
Lilia Biktash
The effects of total solar irradiance (TSI) and volcanic activity on long-term global temperature variations during solar cycles 19-23 were studied. It was shown that a large proportion of climate variations can be explained by the mechanism of action of TSI and cosmic rays (CRs) on the state of the lower atmosphere and other meteorological parameters. The role of volcanic signals in the 11-year variations of the Earth's climate can be expressed as several years of global temperature drop. Conversely, it was shown that the effects of solar, geophysical, and human activity on climate change interact...
July 2017: Journal of Advanced Research
https://www.readbyqxmd.com/read/28372076/auditory-display-of-seismic-data-on-the-use-of-experts-categorizations-and-verbal-descriptions-as-heuristics-for-geoscience
#10
Arthur Paté, Lapo Boschi, Danièle Dubois, Jean-Loïc Le Carrou, Benjamin Holtzman
Auditory display can complement visual representations in order to better interpret scientific data. A previous article showed that the free categorization of "audified seismic signals" operated by listeners can be explained by various geophysical parameters. The present article confirms this result and shows that cognitive representations of listeners can be used as heuristics for the characterization of seismic signals. Free sorting tests are conducted with audified seismic signals, with the earthquake/seismometer relative location, playback audification speed, and earthquake magnitude as controlled variables...
March 2017: Journal of the Acoustical Society of America
https://www.readbyqxmd.com/read/28366622/chronobiological-studies-on-body-search-oviposition-and-emergence-of-megaselia-scalaris-diptera-phoridae-in-controlled-conditions
#11
Esta Bostock, Edward W Green, Charalambos P Kyriacou, Stefano Vanin
Circadian clocks have evolved to synchronize physiology, metabolism and behaviour to the 24-h geophysical cycles of the Earth. Understanding the circadian clock mechanism could play an important role in forensic entomology because it temporally gates behaviour such as locomotor activities, feeding, mating, egg laying and adult emergence which could provide useful information for crime reconstruction. The scuttle fly Megaselia scalaris colonises both exposed and buried bodies, whether indoors or outdoors. Locomotor activity, oviposition and adult emergence of this species have been investigated using technologies employed in many previous Drosophila circadian studies...
March 18, 2017: Forensic Science International
https://www.readbyqxmd.com/read/28364772/a-perturbation-theoretic-approach-to-lagrangian-flow-networks
#12
Naoya Fujiwara, Kathrin Kirchen, Jonathan F Donges, Reik V Donner
Complex network approaches have been successfully applied for studying transport processes in complex systems ranging from road, railway, or airline infrastructures over industrial manufacturing to fluid dynamics. Here, we utilize a generic framework for describing the dynamics of geophysical flows such as ocean currents or atmospheric wind fields in terms of Lagrangian flow networks. In this approach, information on the passive advection of particles is transformed into a Markov chain based on transition probabilities of particles between the volume elements of a given partition of space for a fixed time step...
March 2017: Chaos
https://www.readbyqxmd.com/read/28364756/spatio-temporal-organization-of-dynamics-in-a-two-dimensional-periodically-driven-vortex-flow-a-lagrangian-flow-network-perspective
#13
Michael Lindner, Reik V Donner
We study the Lagrangian dynamics of passive tracers in a simple model of a driven two-dimensional vortex resembling real-world geophysical flow patterns. Using a discrete approximation of the system's transfer operator, we construct a directed network that describes the exchange of mass between distinct regions of the flow domain. By studying different measures characterizing flow network connectivity at different time-scales, we are able to identify the location of dynamically invariant structures and regions of maximum dispersion...
March 2017: Chaos
https://www.readbyqxmd.com/read/28364754/edge-anisotropy-and-the-geometric-perspective-on-flow-networks
#14
Nora Molkenthin, Hannes Kutza, Liubov Tupikina, Norbert Marwan, Jonathan F Donges, Ulrike Feudel, Jürgen Kurths, Reik V Donner
Spatial networks have recently attracted great interest in various fields of research. While the traditional network-theoretic viewpoint is commonly restricted to their topological characteristics (often disregarding the existing spatial constraints), this work takes a geometric perspective, which considers vertices and edges as objects in a metric space and quantifies the corresponding spatial distribution and alignment. For this purpose, we introduce the concept of edge anisotropy and define a class of measures characterizing the spatial directedness of connections...
March 2017: Chaos
https://www.readbyqxmd.com/read/28360005/origin-of-hexavalent-chromium-in-groundwater-the-example-of-sarigkiol-basin-northern-greece
#15
N Kazakis, N Kantiranis, K Kalaitzidou, E Kaprara, M Mitrakas, R Frei, G Vargemezis, P Tsourlos, A Zouboulis, A Filippidis
Hexavalent chromium constitutes a serious deterioration factor for the groundwater quality of several regions around the world. High concentrations of this contaminant have been also reported in the groundwater of the Sarigkiol hydrological basin (near Kozani city, NW Greece). Specific interest was paid to this particular study area due to the co-existence here of two important factors both expected to contribute to Cr(VI) presence and groundwater pollution; namely the area's exposed ophiolitic rocks and its substantial fly ash deposits originating from the local lignite burning power plant...
March 28, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28332561/inertial-bioluminescence-rhythms-at-the-capo-passero-km3net-italia-site-central-mediterranean-sea
#16
J Aguzzi, E Fanelli, T Ciuffardi, A Schirone, J Craig
In the deep sea, the sense of time is dependent on geophysical fluctuations, such as internal tides and atmospheric-related inertial currents, rather than day-night rhythms. Deep-sea neutrino telescopes instrumented with light detecting Photo-Multiplier Tubes (PMT) can be used to describe the synchronization of bioluminescent activity of abyssopelagic organisms with hydrodynamic cycles. PMT readings at 8 different depths (from 3069 to 3349 m) of the NEMO Phase 2 prototype, deployed offshore Capo Passero (Sicily) at the KM3NeT-Italia site, were used to characterize rhythmic bioluminescence patterns in June 2013, in response to water mass movements...
March 23, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28332519/simultaneous-tracking-of-spin-angle-and-amplitude-beyond-classical-limits
#17
Giorgio Colangelo, Ferran Martin Ciurana, Lorena C Bianchet, Robert J Sewell, Morgan W Mitchell
Measurement of spin precession is central to extreme sensing in physics, geophysics, chemistry, nanotechnology and neuroscience, and underlies magnetic resonance spectroscopy. Because there is no spin-angle operator, any measurement of spin precession is necessarily indirect, for example, it may be inferred from spin projectors at different times. Such projectors do not commute, and so quantum measurement back-action-the random change in a quantum state due to measurement-necessarily enters the spin measurement record, introducing errors and limiting sensitivity...
March 22, 2017: Nature
https://www.readbyqxmd.com/read/28325934/cordillera-zealandia-a-mesozoic-arc-flare-up-on-the-palaeo-pacific-gondwana-margin
#18
L A Milan, N R Daczko, G L Clarke
Two geochemically and temporally distinct components of the Mesozoic Zealandia Cordilleran arc indicate a shift from low to high Sr/Y whole rock ratios at c. 130 Ma. Recent mapping and a reappraisal of published Sr-Nd data combined with new in-situ zircon Hf isotope analyses supports a genetic relationship between the two arc components. A reappraisal of geophysical, geochemical and P-T estimates demonstrates a doubling in thickness of the arc to at least 80 km at c. 130 Ma. Contemporaneously, magmatic addition rates shifted from ~14 km(3)/my per km of arc to a flare-up involving ~100 km(3)/my per km of arc...
March 21, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28319845/surface-transport-processes-in-charged-porous-media
#19
Jorge Gabitto, Costas Tsouris
Surface transport processes are very important in chemistry, colloidal sciences, engineering, biology, and geophysics. Natural or externally produced charges on surfaces create electrical double layers (EDLs) at the solid-liquid interface. The existence of the EDLs produces several complex processes including bulk and surface transport of ions. In this work, a model is presented to simulate bulk and transport processes in homogeneous porous media comprising big pores. It is based on a theory for capacitive charging by ideally polarizable porous electrodes without Faradaic reactions or specific adsorption of ions...
March 3, 2017: Journal of Colloid and Interface Science
https://www.readbyqxmd.com/read/28303951/enhancing-the-sensitivity-of-magnetic-sensors-by-3d-metamaterial-shells
#20
Carles Navau, Rosa Mach-Batlle, Albert Parra, Jordi Prat-Camps, Sergi Laut, Nuria Del-Valle, Alvaro Sanchez
Magnetic sensors are key elements in our interconnected smart society. Their sensitivity becomes essential for many applications in fields such as biomedicine, computer memories, geophysics, or space exploration. Here we present a universal way of increasing the sensitivity of magnetic sensors by surrounding them with a spherical metamaterial shell with specially designed anisotropic magnetic properties. We analytically demonstrate that the magnetic field in the sensing area is enhanced by our metamaterial shell by a known factor that depends on the shell radii ratio...
March 17, 2017: Scientific Reports
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