bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of Fines Content on the Mechanical Behavior of Methane Hydrate‐Bearing Sediments
Authors: Hyodo Masayuki , Wu Yang , Nakashima Koji , Kajiyama Shintaro , Nakata Yukio 
Published: September 2017

AbstractMethane hydrate‐bearing sediments with different amounts of fines content and at three densities were artificially prepared under controlled temperature and pressure conditions. The void ratios of specimens after isotropic consolidation tend to decrease with a rise in fines content. The fines particles enter into the pore space between sand grains and densify the specimens. A series of triaxial compression tests were performed to systematically investigate the influences of fines content and density on the shear properties of hydrate‐free sediments and methane hydrate‐bearing sediments. The test results demonstrate that a rise in fines content within methane hydrate‐bearing sediments significantly enhances peak shear strength and promotes dilation behavior. These influences are particularly prominent for specimens at loose packing state. A decrease in void ratio increases the shear strength and stiffness of hydrate‐free sediments and methane hydrate‐bearing sediments containing fines content of 0% and 8.9%. It is noted that the formation of methane hydrate in samples with varying amounts of fines content increases the stress ratios at the critical state. The addition of fines particles into coarse‐grained sand grains alters the internal microstructure of sand matrix and the hydrate formation pattern in the pore space between sand grains and fines particles.
Seismicity Induced by Hydraulic Fracturing in Shales: A Bedding Plane Slip Model
Authors: Staněk František , Eisner Leo 
Published: September 2017

AbstractPassive seismic monitoring of microseismic events induced in oil or gas reservoirs is known as microseismic monitoring. Microseismic monitoring is used to understand the process of hydraulic fracturing, which is a reservoir stimulation technique. We use a new geomechanical model with bedding plane slippage induced by hydraulic fractures within shale reservoirs to explain seismicity observed in a typical case study of hydraulic fracturing of a shale gas play in North America. Microseismic events propagating from the injection point are located at similar depths (within the uncertainty of their locations), and their source mechanisms are dominated by shear failure with both dip‐slip and strike‐slip senses of motion. The prevailing dip‐slip mechanisms have one nearly vertical nodal plane perpendicular to the minimum horizontal stress axis, while the other nodal plane is nearly horizontal. Such dip‐slip mechanisms can be explained by slippage along bedding planes activated by the aseismic opening of vertical hydraulic fractures. The model explains the observed prevailing orientation of the shear planes of the microseismic events, as well as the large difference between seismic and hydraulic energy.
Locating Microseism Sources Using Spurious Arrivals in Intercontinental Noise Correlations
Authors: Retailleau Lise , Boué Pierre , Stehly Laurent , Campillo Michel 
Published: September 2017

AbstractThe accuracy of Green's functions retrieved from seismic noise correlations in the microseism frequency band is limited by the uneven distribution of microseism sources at the surface of the Earth. As a result, correlation functions are often biased as compared to the expected Green's functions, and they can include spurious arrivals. These spurious arrivals are seismic arrivals that are visible on the correlation and do not belong to the theoretical impulse response. In this article, we propose to use Rayleigh wave spurious arrivals detected on correlation functions computed between European and United States seismic stations to locate microseism sources in the Atlantic Ocean. We perform a slant stack on a time distance gather of correlations obtained from an array of stations that comprises a regional deployment and a distant station. The arrival times and the apparent slowness of the spurious arrivals lead to the location of their source, which is obtained through a grid search procedure. We discuss improvements in the location through this methodology as compared to classical back projection of microseism energy. This method is interesting because it only requires an array and a distant station on each side of an ocean, conditions that can be met relatively easily.
Mapping of a Typhoon‐Driven Coastal Upwelling by Assimilating Coastal Acoustic Tomography Data
Authors: Chen Minmo , Kaneko Arata , Lin Ju , Zhang Chuanzheng 
Published: September 2017

AbstractA typhoon‐driven upwelling event was observed with coastal acoustic tomography in Hiroshima Bay during September 2013. The tomography data were used to obtain state estimates from an ocean model, employing the ensemble Kalman filter (EnKF) for data assimilation. Hiroshima Bay was represented as a two‐layer system with a fresh, near‐surface layer overlaying a more saline, lower layer. Wind from the typhoon forced the surface layer southward, thus drawing the lower layer northward and causing upwelling. After the upwelling, these currents reversed for a period. During the upwelling, the total volume transports for the upper and lower layers were well balanced, showing continuity of the two layers. However, the total upper layer volume transported northward during the reverse‐flow period was significantly smaller than the total upper layer volume transported southward during the upwelling, and significantly larger than the total lower layer volume transported southward during the reverse‐flow period. The downstream reductions of transported volume indicated mixing fractions of 24%–30%, with water mixing at the interface of the upper and lower layers. Errors in state estimates were less than the changes in current and salinity associated with the upwelling.
Air‐Sea CO2 Exchange in the Ross Sea, Antarctica
Authors: DeJong Hans B. , Dunbar Robert B. 
Published: September 2017

AbstractAlthough the Ross Sea is one of the most productive regions in Antarctica, it is not clear to what extent this region is an atmospheric CO2 sink. We calculate instantaneous CO2 flux rates with in situ pCO2 and wind speed data from 20 cruises in the Ross Sea. In addition, we estimate annual CO2 fluxes into the Ross Sea with nutrient budgets from a late summer cruise. We find that the Ross Sea is a lesser atmospheric CO2 sink (–7.5 ± 0.5 Tg C yr−1, −1.3 ± 0.1 mol C m−2 yr−1) than previously reported (–13 Tg C yr−1, −1.7 to −4.2 mol C m−2 yr−1). One exception is Terra Nova Bay (TNB) in the western Ross Sea, with CO2 flux rates (–4.8 ± 0.3 mol C m−2, January–March) that are 3–4 times greater than the Ross Sea mean. The majority of the CO2 flux into TNB occurs during the late summer with instantaneous CO2 flux rates up to −246 mmol C m−2 d−1. These extraordinary CO2 flux rates are caused by the unique coupling of strong katabatic winds and low surface pCO2 values. Although strong katabatic winds deepen the mixed layer and entrain CO2‐rich water from below, late season net community productivity maintains low surface water pCO2 levels. While TNB only covers ∼1% (3,600 km2) of the Ross Sea continental shelf, extraordinary air‐to‐sea CO2 fluxes during the late summer may be regular features in many of the major sea ice production polynyas (148,000 km2 combined), including Antarctic Bottom Water formation regions.
Internal Solitary Wave Reflection Near Dongsha Atoll, the South China Sea
Authors: Bai Xiaolin , Li Xiaofeng , Lamb Kevin G. , Hu Jianyu 
Published: September 2017

AbstractInternal solitary wave (ISW) reflection is rarely observed in satellite images, even in the South China Sea (SCS), where the strongest and most energetic ISWs in the world have been observed. Compared to the large number of satellite images showing shoaling ISW in the SCS, fewer than 10 satellite images have been reported showing ISW reflection. In this study, we collect recent satellite images and implement a numerical model to analyze ISW reflection near Dongsha Atoll, in the SCS. Satellite observations show that the reflection appears to be associated with the large‐amplitude ISWs generated by strong tidal currents in Luzon Strait. Numerical simulations show that ISWs break when reaching the sloping bottom. Part of ISW energy is reflected by mode‐1 waves and their trailing mode‐2 waves. The mode‐1 waves have two types: long inertia‐gravity waves and breaking ISW‐induced short waves. They propagate quickly but induce weak vertical velocity and surface imprints. Mode‐2 waves induce strong vertical velocity, showing visible signature in satellites. Horizontal distribution of the energy indicates that a maximum energy of about 2% of the incident energy is contained in a single reflected wave. This could explain why the reflected waves are rarely observed, because reflected waves must be sufficiently large to be detected in satellite images. Although individual wave's energy is small, in total up to 20% of the incident wave is reflected by the groups of mode‐1 and mode‐2 waves. This suggests that ISW reflection has a significant impact on energy distribution over the continental slopes.
The Dynamics of Cuba Anticyclones (CubANs) and Interaction With the Loop Current/Florida Current System
Authors: Kourafalou Vassiliki , Androulidakis Yannis , Le Hénaff Matthieu , Kang HeeSook 
Published: September 2017

AbstractMesoscale anticyclonic eddies along the northern Cuban coast (CubANs) have been identified in the Straits of Florida, associated with the northward shift of the Florida Current (FC) and the anticyclonic curvature of the Loop Current (LC) at the western entrance of the Straits. The dynamics of CubAN eddies and their interaction with the LC/FC system are described for the first time using satellite, drifter and buoy data, and a high‐resolution model. It is shown that the evolution of CubANs to the south of the FC front complements the evolution of cyclonic eddies to the north of the FC, advancing previous studies on synergy between FC meandering and eddy activity. Two types of CubAN eddies are characterized: (a) a main anticyclonic cell (type “A”) within the core of the LC during retracted phase conditions, associated with the process of LC Eddy (LCE) shedding from an extended LC, and (b) an individual, distinct anticyclonic eddy that is released from the main LC core and is advected eastward, along the northern Cuban coast (type “B”). There are also mixed cases, when the process of LCE shedding has started, so a type “A” CubAN is being formed, in the presence of one or more eastward progressing type “B” eddies. CubAN evolution is associated with an increased mixed layer and weaker stratification of the upper ocean along the eddy's track. The cyclonic activity along the Cuban coast and wind‐induced upwelling events also contribute to the evolution and fate of the CubAN eddies.
The 2004 Sumatra tsunami in the Southeastern Pacific Ocean: New Global Insight from Observations and Modeling
Authors: Rabinovich A. B. , Titov V. V. , Moore C. W. , Eblé M. C. 
Published: September 2017

AbstractThe 2004 Sumatra tsunami was an unprecedented global disaster measured throughout the world oceans. The present study focused on a region of the southeastern Pacific Ocean where the “westward” circumferentially propagating tsunami branch converged with the “eastward” branch, based on data from fortuitously placed Chilean DART 32401 and tide gauges along the coast of South America. By comparison of the tsunami and background spectra, we suppressed the influence of topography and reconstructed coastal “spectral ratios” that were in close agreement with a ratio at DART 32401 and spectral ratios in other oceans. Findings indicate that even remote tsunami records carry spectral source signatures (“birth‐marks”). The 2004 tsunami waves were found to occupy the broad frequency band of 0.25–10 cph with the prominent ratio peak at period of 40 min related to the southern fast‐slip source domain. This rupture “hot‐spot” of ∼350 km was responsible for the global impact of the 2004 tsunami. Data from DART 32401 provided validation of model results: the simulated maximum tsunami wave height of 2.25 cm was a conservative approximation to the measured height of 2.05 cm; the computed tsunami travel time of 25 h 35 min to DART 32401, although 20 min earlier than the actual travel time, provided a favorable result in comparison with 24 h 25 min estimated from classical kinematic theory. The numerical simulations consistently reproduced the wave height changes observed along the coast of South America, including local amplification of tsunami waves at the northern stations of Arica (72 cm) and Callao (67 cm).
The Mass‐Dimensional Properties of Cirrus Clouds During TC4
Authors: Mascio Jeana , Xu Zhuocan , Mace Gerald G. 
Published: September 2017

AbstractRemote sensing retrievals and ice microphysical parameterizations in global climate models typically use assumptions about the distribution of ice mass as a function of particle size using mass‐dimensional (m‐D) relationships. This study investigates the ice crystal m‐D properties of tropical anvil cirrus during the Tropical Composition, Cloud and Climate Coupling Experiment (TC4) to better document the distribution of ice mass with size in this particular class of tropical ice clouds. Two optimal estimation algorithms (XIWC and MZ) are used to estimate the m‐D relationship for each particle size distribution (PSD) collected in situ. The XIWC algorithm minimizes the difference between measured ice water content (IWC) and PSD calculated IWC, while the MZ algorithm minimizes the difference between measured radar reflectivity factors and those calculated from the in situ PSDs. Results from these algorithms are compared to previous studies to establish consistency of the methodologies. The XIWC results show that both parameters in the m‐D relationship increase with temperature. Changes in m‐D with temperature have substantial implications for remote sensing retrievals. With the prefactor varying by a factor of 5 and the exponent varying by some 16% over a typical range of ice cloud temperatures, forward modeling errors in radar reflectivity could be typically in excess of 5 dB, further suggesting that retrievals of IWC and precipitation rates from radar measurements in ice clouds be in error by factors easily exceeding 3.
Subtropical Dust Storms and Downslope Wind Events
Authors: Pokharel Ashok Kumar , Kaplan Michael L. , Fiedler Stephanie 
Published: September 2017

AbstractWe performed detailed mesoscale observational analyses and Weather Research and Forecasting (WRF) model simulations to study the terrain‐induced downslope winds that generated dust‐emitting winds at the beginning of three strong subtropical dust storms in three distinctly different regions of North Africa and the Arabian Peninsula. We revisit the Harmattan dust storm of 2 March 2004, the Saudi dust storm of 9 March 2009, and the Bodélé Depression dust storm of 8 December 2011 and use high‐resolution WRF modeling to assess the dynamical processes during the onset of the storms in more depth. Our results highlight the generation of terrain‐induced downslope winds in response to the transition of the atmospheric flow from a subcritical to supercritical state in all three cases. These events precede the unbalanced adjustment processes in the lee of the mountain ranges that produced larger‐scale dust aerosol mobilization and transport. We see that only the higher‐resolution data sets can resolve the mesoscale processes, which are mainly responsible for creating strong low‐level terrain‐induced downslope winds leading to the initial dust storms.
Mutual Dependence Between Sedimentary Organic Carbon and Infaunal Macrobenthos Resolved by Mechanistic Modeling
Authors: Zhang Wenyan , Wirtz Kai 
Published: September 2017

AbstractThe mutual dependence between sedimentary total organic carbon (TOC) and infaunal macrobenthos is here quantified by a mechanistic model. The model describes (i) the vertical distribution of infaunal macrobenthic biomass resulting from a trade‐off between nutritional benefit (quantity and quality of TOC) and the costs of burial (respiration) and mortality, and (ii) the variable vertical distribution of TOC being in turn shaped by bioturbation of local macrobenthos. In contrast to conventional approaches, our model emphasizes variations of bioturbation both spatially and temporally depending on local food resources and macrobenthic biomass. Our implementation of the dynamic interaction between TOC and infaunal macrobenthos is able to capture a temporal benthic response to both depositional and erosional environments and provides improved estimates of the material exchange flux at the sediment‐water interface. Applications to literature data for the North Sea demonstrate the robustness and accuracy of the model and its potential as an analysis tool for the status of TOC and macrobenthos in marine sediments. Results indicate that the vertical distribution of infaunal biomass is shaped by both the quantity and the quality of OC, while the community structure is determined only by the quality of OC. Bioturbation intensity may differ by 1 order of magnitude over different seasons owing to variations in the OC input, resulting in a significant modulation on the distribution of OC. Our relatively simple implementation may further improve models of early diagenesis and marine food web dynamics by mechanistically connecting the vertical distribution of both TOC and macrobenthic biomass.
Sources, Sinks, and Subsidies: Terrestrial Carbon Storage in Mid‐latitude Fjords
Authors: Smeaton Craig , Austin William E. N. 
Published: September 2017

AbstractFjords are recognized as globally important sites for the burial and long‐term storage of carbon (C) within sediments. The proximity of fjords to the terrestrial environment in combination with their geomorphology and hydrography results in the fjordic sediments being subsidized with organic carbon (OC) from the terrestrial environment. It has been well documented that terrestrial OC (OCterr) is an important component of coastal sediments, yet our understanding of the quantity of OCterr stored in these sediments remains poorly constrained. Utilizing Bayesian isotopic sediment fingerprinting techniques to the surface sediments of Loch Sunart, we estimate that 42.0 ± 10.1% of the OC is terrestrial in origin. Through combining these outputs with sedimentary OC stock estimates, we have calculated that the surface sediments (0–15 cm) hold 0.1 megaton (Mt) OCterr and estimate that the postglacial sediment held within the fjord contains 3.96 Mt OCterr. When these totals are compared to the quantity of OC stored in the adjacent terrestrial environment, it is clear that the fjord's catchment stores a greater amount of OCterr in the form of vegetation and soil. Though when normalized for area the results suggest that the marine sediments are a more effective long‐term store of OCterr than the adjacent terrestrial environment. This striking result highlights the importance of the terrestrial environment as a source of OC to the coastal ocean and that the OCterr subsidy to the marine sediments is a significant mechanism for the long‐term storage of OC in coastal marine sediments.
Food Waste
Authors: Reynolds Christian , Mavrakis Vicki 
Published: September 2017

Abstract
Food waste is more than just an unwarranted economic and environmental problem. Food waste provides information on societal values, norms, and beliefs through the classification of what is and what is not considered food waste. This entry discusses the evolution of the “hidden” practice of food waste, and how different conceptions and theories of food waste have emerged over the last 50 years.
Voluntary Simplicity Movement
Authors: Alexander Samuel 
Published: September 2017

AbstractThe voluntary simplicity movement can be understood broadly as a diverse social movement made up of people who are resisting high consumption lifestyles and who are seeking, in various ways, a lower consumption but higher quality of life alternative. Variously defended by its advocates on personal, social, humanitarian, ecological, and even spiritual grounds, voluntary simplicity is based on the assumption that human beings can live meaningful, free, happy, and infinitely diverse lives while consuming no more than a sustainable and equitable share of nature.
Cultural Dopes
Authors: Lynch Michael 
Published: September 2017

Abstract
The term “cultural dope” was first used by Harold Garfinkel, the founder of ethnomethodology (a research program for investigating the social and interactional production of actions in specific circumstances). The term “cultural dope” invites criticism of social scientific models that place specific actions in a dependent relationship to general cultural norms and institutional structures. According to such models, “actors” are unreflective rule followers who reproduce patterns of action without being aware of how they do so. However, the implied critique of deterministic cultural models does not imply a contrary model of the individual as a fully conscious, self‐reflexive rational agent, but instead suggests that specific actions and interactions are bound up in particular situations and interpersonal relations that do not simply follow from generalized rules, plans, ideologies, or other stable cultural conditions.
Cyberlibertarianism
Authors: Dahlberg Lincoln 
Published: September 2017

Abstract
Cyberlibertarianism is the name given to any discourse that sees the Internet and related digital media technology as paving the way to individual liberty, free from centralized bureaucratic systems. Many digital media commentators and practitioners who can be categorized as cyberlibertarian argue that liberty is realized through Internet communication escaping governments and enhancing free markets. However, there are also other forms of cyberlibertarianism that do not so readily embrace free markets, including an anarchist variety that sees the Internet as enabling freedom through bypassing not just governments but also capitalist systems. This entry discusses the meaning of the term “cyberlibertarianism” by sketching its various historical articulations.
B
achelard,
G
aston (1884–1962)
Authors: Chimisso Cristina 
Published: September 2017

Abstract
Gaston Bachelard (1884–1962) was a French philosopher who wrote on science and the imagination. He is the main representative of the French tradition in the philosophy of science that has been named historical epistemology. Of particular importance for subsequent scholars have been his concepts of epistemological break, epistemological obstacle, and regional rationalism. His views of knowledge as rectified error, and of scientific object as sharply distinct from the natural object, have also been influential. The philosophers Michel Foucault and Louis Althusser and the sociologist Pierre Bourdieu have drawn significantly on his philosophy.