bluuebunny/crossref_metadata_2025 huggingface dataset:
Terres et déserts, société et sauvagerie
Authors: Herzog Tamar
Published: May 2019

Cet article envisage le débat concernant le regroupement des Indiens en villages (réductions au Pérou,congregacionesen Nouvelle-Espagne) dans l’Amérique espagnole coloniale. Plutôt qu’une stratégie visant à l’extraction des ressources, cette politique correspond à une représentation selon laquelle ceux qui vivaient sans enracinement communautaire étaient une menace sociale, car ils vivaient sans roi, ni religion, ni terre. Et leur conduite, alléguait-on, était à l’origine d’un environnement physique lui-même dangereux. Une telle association entre espace sauvage et vie hors communauté opérait de la même manière en Castille, et, en Amérique, était appliquée aux Espagnols, aux métis et aux Noirs comme aux Indiens. Envisager en parallèle les débats concernant le traitement des Indiens et des autres secteurs sociaux permet de dépasser la fausse opposition entre le monde indien et le monde espagnol, et d’examiner les échos existant entre les colonisations interne et externe.
Modèles et modalités: les fêtes vice-royales au Mexique et au Pérou, xvie-xviie siècle
Authors: Alberro Solange
Published: May 2019

Les fêtes vice-royales du Mexique et du Pérou colonial suivirent les modèles en vigueur dans l’Espagne impériale. Inspirées de l’Antiquité gréco-romaine et de la tradition bourgui-gnonne, elle avaient un caractère mixte et universel. Unissant le religieux au profane, le lettré au populaire, elles mettaient en scène les dieux, héros et monarques fondateurs des imaginaires propres aux divers territoires constituant l’empire des Habsbourg et tous les acteurs de la société se devaient d’y participer. Par leur nécessaire adaptation aux contextes locaux, garantie de leur efficacité, ces fêtes en vinrent à exprimer les intérêts et les aspirations identitaires de secteurs particuliers à travers l’appropriation, la réhabilitation ou la réinterprétation qu’ils firent des figures, images et symboles dont le modèle festif prescrivait le déploiement.
« Nous vivons dans l’oubli de nos métamorphoses… »: La mort et la sculpture du vivant
Authors: Ameisen Jean Claude
Published: May 2019

Les nouvelles avancées de la biologie invitent à penser le vivant comme un ensemble permanent de métamorphoses. Cette conférence montre que des mécanismes comme celui de la mort cellulaire programmée, ou « suicide cellulaire », par lesquels sont sculptées les formes du vivant, conduisent à reconsidérer notre conception de la vie et de la mort, à distance à la fois de la tentation anthropomorphique et de la sociobiologie. C’est alors toute la complexité du vivant, de l’organisation cellulaire aux formes du social, qui est à repenser, à la lumière des nouveaux savoirs biologiques et médicaux.
Provincialiser l’empire: Chypre et la Méditerranée ottomane au XIXesiècle
Authors: Aymes Marc
Published: May 2019

D’un côté, l’immense ensemble appelé empire ottoman; de l’autre, infime en comparaison, la localité de Chypre. À l’intersection entre la panoramique globalité venue du « centre » et la singularité irréductible du « savoir local », la province est proposée ici comme outil de compréhension de la géométrie variable du monde ottoman. Provincialiser l’empire vise à éviter l’univocité des paradigmes dichotomiques (où s’opposent, par exemple,centreetpériphérie), pour mieux appréhender les flux non congruents qu’il enchevêtre. Ainsi se dessinent les profils démultipliés de personnages qui peuvent être considérés comme autant de figures de l’Ottoman de province.
Co-opting psychiatry: The alliance between academic psychiatry and the pharmaceutical industry
Authors: Moncrieff Joanna
Published: May 2019

The Editorial present the arguments that an alliance between academic psychiatry and the pharmaceutical industry is harmful through a critical review of the academic literature and media coverage of activities of the pharmaceutical industry. The industry and the psychiatric profession both gain advantages from promoting biomedical models of psychiatric disturbance and pharmacological treatment. This confluence of interests has lead to the exaggeration of the efficacy of psychiatric drugs and neglect of their adverse effects and has distorted psychiatric knowledge and practice. Academic psychiatry has helped the industry to colonise more and more areas of modern life in order to expand the market for psychotropic drugs. Persuading people to understand their problems as biological deficiencies obscures the social origin and context of distress and prevents people from seeking social or political solutions. Psychiatry has the power to challenge the dominance of the pharmaceutical industry and should put its efforts into developing alternatives to routine drug treatment. Psychiatry needs to disengage from the industry if it wants to make genuine advances in understanding psychiatric disorder and help reverse the harmful social consequences of the widening medicalisation of human experience.
Italian social psychiatry research: What gets published in peer reviewed journals?
Authors: Galeazzi Gian Maria , Priebe Stefan
Published: May 2019

Aims– To explore the current state of Italian social psychiatry research as evidenced by original papers published in peer-reviewed journals 2004-2006.Methods– Electronic databases and hand searches of leading peer-reviewed journals were used to identify original research papers published in 2004-2006, addressing a social psychiatric issue, having at least one Italian author, and reporting data from Italian samples.Results– A total of 174 papers were identified. A substantial proportion reported findings of international collaborative research. Quantitative methods dominated, with 86 papers on cross-sectional surveys. Only 18 papers showed results of intervention trials with pre and post measures. Most common target group were psychiatric patients in community mental health services which featured in 93 papers.Conclusions– There is a critical mass of Italian social psychiatry research, dominated by a few research centres and with considerable amount of international collaboration. The findings of this survey might reflect the relative shortage of national funding for social psychiatry research.

Declaration of Interest: None.
The assessment of patient involvement across consultation. The Italian version of the Option Scale
Authors: Goss Claudia , Fontanesi Silvia , Mazzi Maria Angela , Piccolo Lidia Del , Rimondini Michela
Published: May 2019

Aim – To present the Italian version of the OPTION (observing patient involvement) rating scale, developed in UK by Elwyn et al. (2005), and its psychometric characteristics, together with some findings when applied on the consultations transcripts of a group of Italian General Practitioners. Methods – The OPTION scale assesses the extent to which clinicians involve patients in decisions and consists of 12 items to be rated on a 5 point scale (from 0 - behaviour not observed to 4 -high standard). The scale was applied to 235 transcripts of audiotaped consultations conducted by 6 male GPs. Interrater and test-retest reliability and internal validity indices were calculated on a subsample of 30 transcripts. Results – The Italian language version of OPTION showed good psychometric properties, similar to those reported for the original version. The ratings obtained for 235 consultations showed for each OPTION item a skewed distribution: the majority of scores (> 70%) were between 0 (behaviour absent) and 2 (minimum skill level). Conclusions – The Italian language version of OPTION seems a reliable instrument to assess patient involvement in primary care settings also in Italy. The clustering of low scores confirms previous findings that clinicians without a specific training obtain very low levels of patient involvement in the decision making process.

Declaration of Interest: None.
Residential facilities and day centres in mental health. Is there any difference?
Authors: D'Avanzo Barbara , Aliprandini Eugenia , Beghi Massimiliano , Cornaggia Cesare Maria , Erlicher Arcadio , Frova Maria , Mascarini Alessandra , Miragoli Paolo , Righi Augusto
Published: May 2019

Aims– We wanted to investigate to what extent and in what characteristics the patients cared in the psychiatric residential facilities (RF) were similar to those in the day-centres (DC), and whether 6-month improvements in the two settings were comparable.Methods– We described 141 patients admitted to the RF and 180 in DC of three mental health service networks in Milan and near Milan. They were evaluated again after six months.Results– In both groups, we identified subgroups of more intensive treatment: 45% of those in residential treatment were in high intensity rehabilitation facilities, and those who followed a residential program of >12 hours/week were 53%. The mean duration of treatment in the residential treatment was 40 months (SD 55.7) and in DC 49.6 months (49.3). The two groups differed in the overall scores of the HoNOS, but differences emerged in the subscales relative to daily life activities and living conditions. Among those in RF, about half had a house, versus 99% among those in DC. After six months, clinically significant modifications were small in both groups.Conclusions– Residential patients had more needs than DC patients. It is possible that some of the residential patients might be treated with intensive DC program, but the absence of a home for the majority of residential facilities patients makes this unlikely.

Declaration of Interest: None.
The communication of the diagnosis of schizophrenia. Focus group findings on psychiatrists' point of view
Authors: Paccaloni Monica , Rimondini Michela , Pozzan Tecla , Zimmermann Christa
Published: May 2019

Aims– Evidence from the literature show that patients affected by psychosis rarely are informed about their diagnosis and/or involved in the decision making process regarding the therapeutic program. The aim of the present study is to investigate psychiatrists' clinical experiences, beliefs and attitudes towards communicating the diagnosis to patients affected by psychosis.Method– Three focus groups were conducted with 28 psychiatrists of different levels of expertise (10 senior psychiatrists and 18 psychiatrists in training), all working at the South-Verona Community-based Mental Health Service. The group discussions were audiotaped and transcribed. The authors derived different thematic categories which were used by two raters to classify all contributions of the psychiatrists.Results– The main themes of interest which emerged were: experience with the communication of the diagnosis of psychosis and main communication strategies used; obstacles and personal difficulties in giving such information.Conclusions– In the psychiatric setting the disclosure of the diagnosis of psychosis implies different clinical and ethical issues and is felt as highly problematic. These findings suggest a need of psychiatrists to involve the psychotic patient in the information giving process in order to learn his/her informative needs which are the starting point for individually tailored information.

The authors have no potential conflict of interest related to the subject of the paper. No economic support has been received for this study.
Psychoeducational family interventions for schizophrenia in the last decade: from explanatory to pragmatic trials
Authors: Magliano Lorenza , Fiorillo Andrea
Published: May 2019

A number of explanatory RCT studies published since the 1980s have demonstrated the clinical efficacy of Psychoeducational Family Interventions (PFI) for schizophrenia when provided in combination with drug therapy. In recent years, there has been a shift from efficacy to effectiveness studies and great attention by the researchers in developing training programmes in these interventions for ordinary staff. In this paper, we will provide an overview of the studies on PFI for schizophrenia which have been carried out in the last decade in routine clinical settings or with at least a partial involvement of ordinary staff. These studies have been grouped into: a) studies comparing PFI with standard care; b) studies comparing PFI with individual integrated interventions; c) studies comparing different PFI strategies; d) implementation studies. The results of these studies reveal that, when provided in clinical settings, PFI have positive middle-term effects on patients' clinical status and disability, and limited impact on family burden. From a methodological viewpoint, these studies had several similarities, such as homogeneity of PFI models and mid-term follow-up assessments, and several differences, mainly in the intensity and duration of the family exposure to the intervention. Future studies are needed to identify the “best dose” at which PFI can be provided in routine conditions at the most convenient cost-benefit ratio.
CME: UpDate Aktinische Keratosen
Authors: Angehrn Susanne , Tschernitz Sebastian
Published: May 2019

Zusammenfassung. Aktinische Keratosen (AK) sind durch chronische UVB-Schädigung verursachte Hautveränderungen, die durch gesteigerte Verhornung und Dysplasie der Hautzellen gekennzeichnet sind. AK können in ein Plattenepithelkarzinom übergehen. Die Prävalenz dieser an Sonnenlicht-exponierten Hautstellen auftretenden Erkrankung steigt mit zunehmendem Alter. Die Diagnose ist häufig eine Blickdiagnose. In Rezidiv- oder Zweifelsfällen sollte eine histologische Sicherung erfolgen. Therapeutisch kommen verschiedene Behandlungsmöglichkeiten zur Anwendung, von ablativen bis topisch-medikamentösen Verfahren. Die Prävention hat einen hohen Stellenwert. Dieser Artikel will über das Krankheitsbild informieren, Hilfestellung bei der Erkennung bieten und therapeutische Möglichkeiten aufzeigen.
Spatiotemporal Variations in Crustal Seismic Anisotropy Surrounding Induced Earthquakes Near Fox Creek, Alberta
Authors: Li Tianyang , Gu Yu Jeffrey , Wang Zizhen , Wang Ruijia , Chen Yunfeng , Song Teh‐Ru Alex , Wang Ruihe
Published: May 2019

This study analyzes earthquake recordings from four near‐source (<10 km) stations near Fox Creek, Alberta, a region known for hydraulic fracturing‐induced seismicity. We examine the spatiotemporal variations of focal mechanisms and seismic anisotropy in the sedimentary strata. The focal mechanisms of surrounding earthquake swarms are generally consistent with the strike‐slip mechanism of the ML4.6 earthquake, favoring a flower type of fault structure. The NE‐SW‐orientated fast splitting direction, determined from the shear wave splitting measurements, reflects the combined effects of (1) N‐S faults and (2) NE‐SW time‐dependent hydraulically stimulated fractures. The latter effect dominates the apparent anisotropy during the days leading to the mainshock, while its contributions are reduced by 60–70% after the mainshock. Loss of fluid into the fault damage zone, which causes the closure of fractures, is responsible for the observed spatiotemporal variation of seismic anisotropy near the hydraulic fracturing well.
Boundary Detection in Three Dimensions With Application to the SMILE Mission: The Effect of Model‐Fitting Noise
Authors: Jorgensen Anders M. , Sun Tianran , Wang Chi , Dai Lei , Sembay Steve , Zheng Jianhua , Yu Xizheng
Published: May 2019

The magnetosheath and near‐Earth solar wind emit X‐rays due to charge‐exchange between the extended atmosphere and highly ionized particles in the solar wind. These emissions can be used to remotely sense the dynamic processes in this region. The Solar Wind Magnetosphere Ionosphere Link Explorer mission will carry out these measurements. In a previous paper, we looked at the effect of photon counting statistics on determining the location of the magnetopause and bow shock. In this paper we explore, through simulations, the more challenging question of orbital viewing geometry bias when the model and the emissions do not match each other exactly. Our simulations conclude that while care must be taken to avoid false minima in the fitting, there is very little to no orbital bias in extracting the position and large‐scale shape of the magnetopause and bow shocks from 2‐D X‐ray images from the future Solar Wind Magnetosphere Ionosphere Link Explorer mission.
The Role of Current Sheet Scattering in the Proton Isotropic Boundary Formation During Geomagnetic Storms
Authors: Haiducek John D. , Ganushkina Natalia Y. , Dubyagin Stepan , Welling Daniel T.
Published: May 2019

There is considerable evidence that current sheet scattering (CSS) plays an important role in isotropic boundary (IB) formation during quiet time. However, IB formation can also result from scattering by electromagnetic ion cyclotron waves, which are much more prevalent during storm time. The effectiveness of CSS can be estimated by the parameter, the ratio of the field line radius of curvature to the particle gyroradius. Using magnetohydrodynamic and empirical models, we estimated the parameterKassociated with storm time IB observations on the nightside. We used magnetic field observations from spacecraft in the magnetotail to estimate and correct for errors in theKvalues computed by the models. We find that the magnetohydrodynamic and empirical models produce fairly similar results without correction and that correction increases this similarity. Accounting for uncertainty in both the latitude of the IB and the threshold value ofKrequired for CSS, we found that 29–54% of the IB observations satisfied the criteria for CSS. We found no correlation between the correctedKand magnetic local time, which further supports the hypothesis that CSS played a significant role in forming the observed IBs.
Long‐Term Variations in Solar Wind Parameters, Magnetopause Location, and Geomagnetic Activity Over the Last Five Solar Cycles
Authors: Samsonov A. A. , Bogdanova Y. V. , Branduardi‐Raymont G. , Safrankova J. , Nemecek Z. , Park J.‐S.
Published: May 2019

We use both solar wind observations and empirical magnetopause models to reconstruct time series of the magnetopause standoff distance for nearly five solar cycles. Since the average annual interplanetary magnetic field (IMF) Bz is about zero, and the annual IMF cone angle varies between 54.0° and 61.2°, the magnetopause standoff distance on this timescale depends mostly on the solar wind dynamic pressure. The annual IMF magnitude well correlates with the sunspot number (SSN) with a zero time lag, while the annual solar wind dynamic pressure (Pdyn) correlates reasonably well with the SSN but with 3‐year time lag. At the same time, we find an anticorrelation between Pdyn and SSN in cycles 20–21 and a correlation in cycles 22–24 with 2‐year time lag. Both the annual solar wind density and velocity well correlate with the dynamic pressure, but the correlation coefficient is higher for density than for velocity. The 11‐year solar cycles in the dynamic pressure variations are superimposed by an increasing trend before 1991 and a decreasing trend between 1991 and 2009. The average annual solar wind dynamic pressure decreases by a factor of 3 from 1991 to 2009. Correspondingly, the predicted standoff distance in Lin et al.'s (2010, https://doi.org/10.1029/2009JA014235) magnetopause model increases from 9.7 RE in 1991 to 11.6 RE in 2009. The annual SSN, IMF magnitude, and magnetospheric geomagnetic activity indices display the same trends as the dynamic pressure. We calculate extreme solar wind parameters and magnetopause standoff distance in each year using daily values and find that both extremely small and large standoff distances during a solar cycle preferably occur at solar maximum rather than at solar minimum.
Formation of Plasma Around a Small Meteoroid: Electrostatic Simulations
Authors: Sugar G. , Oppenheim M. M. , Dimant Y. S. , Close S.
Published: May 2019

Obtaining meteoroid mass from head echo radar cross section depends on the assumed plasma density distribution around the meteoroid. An analytical model presented in Dimant and Oppenheim (2017a, https://doi.org/10.1002/2017JA023960; 2017b, https://doi.org/10.1002/2017JA023963) and simulation results presented in Sugar et al. (2018, https://doi.org/10.1002/2018JA025265) suggest the plasma density distribution is significantly different than the spherically symmetric Gaussian distribution used to calculate meteoroid masses in many previous studies. However, these analytical and simulation results ignored the effects of electric and magnetic fields and assumed quasi‐neutrality. This paper presents results from the first particle‐in‐cell simulations of head echo plasma that include electric and magnetic fields. The simulations show that the fields change the ion density distribution by less than ∼2% in the meteor head echo region, but the electron density distribution changes by up to tens of percent depending on the location, electron energies, and magnetic field orientation with respect to the meteoroid path.
Texture Development of Clay‐Rich Sediments Across the Costa Rica Subduction Zone
Authors: Kuehn Rebecca , Stipp Michael , Leiss Bernd
Published: May 2019

During sedimentation, burial, and deformation at active continental margins, clay‐rich sediments develop crystallographic preferred orientations (textures) due to the progressive alignment of phyllosilicates. Such textures help to interpret sedimentation and compaction conditions as well as tectonic processes at convergent margins. At the Costa Rica Trench, subduction and plate boundary deformation between the downgoing oceanic Cocos Plate and the overriding Caribbean Plate was investigated during Integrated Ocean Drilling Program Expeditions 334 and 344 within the Costa Rica Seismogenesis Project. Samples of varying depths from the Cocos Plate, the frontal prism, and the slope of the Caribbean Plate were analyzed regarding their composition and texture. Composition is quite similar for all sample locations of the hemipelagic section across the trench as determined by X‐ray powder analysis. Texture analysis reveals that phyllosilicates in samples from the incoming plate show in general weaker textures than those from upper and middle slope of the overriding plate. Samples from the frontal accretionary prism, however, mostly correspond to the incoming plate fabric according to their oceanic origin. Texture intensity depends on the internal parameters grain size and shape, porosity, and composition as well as compaction and tectonics. In samples from the continental wedge and the frontal accretionary prism, we are able to distinguish tectonically undisturbed compacted sediments from core sections that suffered faulting and folding due to subduction‐related deformation. This helps to constrain a more detailed image of sedimentary compaction and localized as well as distributed deformation across the active continental margin offshore Costa Rica.
Long‐Time Relaxation Induced by Dynamic Forcing in Geomaterials
Authors: Ostrovsky L. , Lebedev A. , Riviere J. , Shokouhi P. , Wu C. , Stuber Geesey M. A. , Johnson P. A.
Published: May 2019

We present a theoretical model and experimental evidence of the long‐time relaxation process (slow dynamics) in rocks and other geomaterials following a dynamic wave excitation, at scales ranging from the laboratory to the Earth. The model is based on the slow recovery of an ensemble of grain contacts and asperities broken by a mechanical impact. It includes an Arrhenius‐type equation for recovery of the metastable, broken contacts. The model provides a characteristic size of the broken contacts (order 10−9 m) and predicts that their number increases with impact amplitude. Theoretical results are in good agreement with the laboratory and field data in that they predict both the logarithmic law of recovery rate and deviations from this law.
Spatial and Intergeneric Variation in Physiological Indicators of Corals in the South China Sea: Insights Into Their Current State and Their Adaptability to Environmental Stress
Authors: Qin Zhenjun , Yu Kefu , Wang Yinghui , Xu Lijia , Huang Xueyong , Chen Biao , Li Yang , Wang Wenhuan , Pan Ziliang
Published: May 2019

It is well known that coral thermal bleaching is mainly caused by abnormally high temperatures, but the spatial/intergeneric variation in coral‐algal symbiosis and its linkage to coral bleaching susceptibility is not well understood. In this study, 654 coral samples were collected from six coral reef regions (CRRs) in the South China Sea (SCS), between the Nansha Islands (~10°N) and Daya Bay (22°50′N). They were analyzed to explore how geographical/environmental variation affects coral bleaching susceptibility. The results showed significant spatial and intergeneric variation in zooxanthellae density, Chlacontent, and tissue biomass. Massive corals generally showed higher values than branching corals for all three parameters across CRRs. Spatial analysis showed that these parameters were lowest in the Nansha Islands and highest in Daya Bay, indicating increases with latitude. Several factors may have accounted for this trend, with the most important being sea surface temperature and nutrients. Additionally, we observed a relationship between physiological parameters and bleaching susceptibility, which was that branching corals had greater bleaching susceptibility than massive corals. Coral community composition and live coral cover data showing increasing dominance of massive corals in the SCS support the above inference. Relatively high‐latitude areas have been proposed as potential refuges for corals under continued global warming and the physiological parameters in the present study seem to support this. However, in spite of the aforementioned results, the smallest live coral cover was found in the northern CRRs. This suggests that this refuge function is currently compromised, mainly due to increasing destructive anthropogenic actions.
Radiative Convective Equilibrium and Organized Convection: An Observational Perspective
Authors: Jakob C. , Singh M. S. , Jungandreas L.
Published: May 2019

Radiative convective equilibrium (RCE) describes a balance between the cooling of the atmosphere by radiation and the heating through latent heat release and surface heat fluxes. While RCE is known to provide an energetic constraint on the atmosphere at the global scale, little is known about the proximity of the atmosphere to RCE at smaller spatial and temporal scales, despite the common use of RCE in idealized modeling studies. Here we provide the first observational evaluation of the scales at which the atmosphere is near RCE. We further use observations of cloud characteristics to investigate the role played by organized convection in the RCE state. While the tropical atmosphere as a whole is near RCE on daily time scales and longer, this is not the case for any given location. Rather, areas in excess of 5,000 × 5,000 km2 must be considered to ensure the atmosphere remains near RCE at least 80% of the time, even for monthly averaged conditions. We confirm that RCE is established through the interplay of regions of active deep convection with high precipitation and weak radiative cooling and regions of subsiding motions leading to shallow cloud states that allow strong radiative cooling with no precipitation. The asymmetry in the maximum amount of radiative cooling and latent heating leads to the well‐known ratio of small areas of precipitation and large regions of subsidence observed in the tropics. Finally, we show that organized deep convection does not occur when regions smaller than 1,000 × 1,000 km2 are near RCE.
Morphological Response of an Alpine Braided Reach to Sediment‐Laden Flow Events
Authors: Bakker Maarten , Antoniazza Gilles , Odermatt Eliott , Lane Stuart N.
Published: May 2019

Braided gravel‐bed rivers show characteristic temporal and spatial variability in morphological change and bedload transport under steady flow and sediment supply rates. Their morphodynamic behavior and long‐term evolution in response to nonstationary external forcing is less well known. We studied daily morphological changes in a well‐constrained reach of an Alpine braided river that is subject to regulated sediment‐laden flows, associated with hydroelectric power exploitation, as well as occasional floods. We found that net reach erosion and deposition were forced by upstream sediment supply, albeit in a nonlinear fashion. The spatial distribution of morphological change and inferred spatially‐distributed sediment transport rates varied strongly along the braided reach and between successive sequences of flushing. Local morphological change was driven by two factors: (1) local relief, leading to the preferential filling of topographic lows and erosion of highs, particularly during longer duration floods, which allow braided dynamics to be maintained; and (2) system memory, leading to a negative autocorrelation in bed level changes where erosion was followed by deposition of similar magnitude and vice versa. This effect was associated with the temporary storage of high sediment loads from flushing due to the abrupt on‐off nature of these flows and reveals the relatively efficient transport of sediment in a river that is heavily impacted upon by flow abstraction. In general, the internal morphodynamics of the braided river condition their own response to external forcing events and thus sediment transfer.
Reconstructing Coastal Sediment Budgets From Beach‐ and Foredune‐Ridge Morphology: A Coupled Field and Modeling Approach
Authors: Ciarletta Daniel J. , Shawler Justin L. , Tenebruso Christopher , Hein Christopher J. , Lorenzo‐Trueba Jorge
Published: May 2019

Preserved beach and foredune ridges may serve as proxies for coastal change, reflecting alterations in sea level, wave energy, or past sediment fluxes. In particular, time‐varying shoreface sediment budgets have been inferred from the relative size of foredune ridges through application of radiocarbon and optically stimulated luminescence dating to these systems over the last decades. However, geochronological control requires extensive field investigation and analysis. Purely field‐based studies might also overlook relationships between the mechanics of sediment delivery to the shoreface and foredune ridges, missing insights about sensitivity to changes in sediment budget. We therefore propose a simple geomorphic model of beach/foredune‐ridge and swale morphology to quantify the magnitude of changes in cross‐shore sediment budget, employing field measurements of ridge volume, ridge spacing, elevation, and shoreline progradation. Model behaviors are constrained by the partitioning of sediment fluxes to the shoreface and foredune ridge and can be used to reproduce several cross‐shore patterns observed in nature. These include regularly spaced ridges (“washboards”), large singular ridges, and wide swales with poorly developed ridges. We evaluate our model against well‐preserved ridge and swale systems at two sites along the Virginia Eastern Shore (USA): Fishing Point, for which historical records provide a detailed history of shoreline progradation and ridge growth, and Parramore Island, for which a relatively more complex morphology developed over a poorly constrained period of prehistoric growth. Our results suggest this new model could be used to infer the sensitivity of field sites across the globe to variations in sediment delivery.
A Statistical Study of Anomalous VHF Propagation Due to the Sporadic‐E Layer in the Air‐Navigation Band
Authors: Sakai J. , Hosokawa K. , Tomizawa I. , Saito S.
Published: May 2019

The sporadic‐E (Es) layer is an ionospheric layer which appears occasionally near 100‐km heights with extremely high electron density. The Es layer may reflect very high‐frequency radio signals when the incident angle is shallow (Es layer anomalous propagation [EsAP]). It is known that radio signals with frequencies above 100 MHz sometimes reach distant locations, more than 600 km apart from the transmitters, due to EsAP. Since air‐navigation radio channels are allocated on frequencies between 108 and 118 MHz, EsAP may interfere with directly propagating wave (ground wave) signals. However, as the occurrence and strength of EsAP on these frequencies have not been studied well, it is difficult to assess the impact of EsAP on the air navigation. In this paper, we report the statistics of the occurrence and strength of EsAP based on a 3‐year continuous monitoring of very high‐frequency air‐navigation radio signal strength on the ground. The statistics show that strong EsAPs occur frequently in summer. The occurrence pattern of EsAP is generally consistent with ionosonde observations of Es layer: Most Es layers appear during summer, primary peak in daytime, with a second peak in the evening. During an extreme EsAP event, in a particular channel, an EsAP signal was superposed on a ground wave signal which resulted in a fluctuation of ground wave signal by more than ±10 dB. Our statistical results suggest that the Es layer has a potential impact on air‐navigation applications.
Stokes‐Brinkman Flow Simulation Based on 3‐D μ‐CT Images of Porous Rock Using Grayscale Pore Voxel Permeability
Authors: Kang Dong Hun , Yang Eomzi , Yun Tae Sup
Published: May 2019

The direct flow simulation using high‐resolution micro‐computed tomographic (μ‐CT) images of porous rock can be used to help understand the flow characteristics at the pore‐scale and to estimate fluid properties; however, segmentation of pore space in grayscale 3‐D μ‐CT images, a necessary step in this process, is challenging because of issues related to the image resolution and pore‐filling matrix in the gray‐level images. We present a novel process for determining the voxel porosity and permeability of the gray‐level regime and evaluating the bulk permeability using the Brinkman force lattice Boltzmann method. In this study, μ‐CT images of Berea sandstone are acquired with two spatial resolutions. After the pore size distribution curve is experimentally obtained, the “apparent pore” voxels and “gray pore” voxels are determined based on the designated gray‐level values in the gray‐level (CT number) histogram, the cumulative and fractional pore volumes, and the linear relationship between CT number and individual voxel porosity. The results show that the boundary between apparent and gray pores in terms of size determines the volumetric fraction and specific surface area. Additionally, the permeability computed by considering the gray pore regime based on the proposed method is more similar to the experimentally measured value than the results of other segmentation methods because the gray pore domain is fully incorporated into the flow domain while preserving the pore connectivity. The proposed sequence of pore segmentation presents a method for handling gray‐level pore space without compromising pore connectivity.
Effect of Hydrogeologic and Climatic Variability on Performance of a Groundwater Market
Authors: Khan Hassaan Furqan , Brown Casey M.
Published: May 2019

Incentive‐based policies, such as the cap‐and‐trade system, have been shown to be useful in the context of groundwater management. This study compares the performance of a groundwater market with water quotas when assumptions of perfect information are violated due to climate change and hydrogeologic heterogeneity and explores how changes in future climate affect market performance. A subbasin of the Republican River Basin, overlying the Ogallala aquifer in the High Plains of the United States, is used as a case study. Building on a previously developed model, a multiagent system model simulating a groundwater market is developed where self‐interested agents can trade water use permits to maximize individual benefits subject to irrigation and land constraints. This economic model is coupled with a calibrated physically based groundwater model for the study region that allows for an evaluation of streamflow depletion impacts, which has been the focus of management efforts in the basin. Results show that trading of permits between farmers results in increased economic benefits and, in some cases, reduced environmental violations. However, the benefits of a groundwater market are distributed unequally resulting in “winners” and “losers” across the system. Future changes in climate are shown to significantly influence farmers willingness to pay for groundwater and thus increase the variation in groundwater price and pumping. These findings emphasize the importance of addressing hydroclimatologic variability and change in the design of groundwater markets.
Modeling Influence of Sediment Heterogeneity on Nutrient Cycling in Streambeds
Authors: Pescimoro Eugenio , Boano Fulvio , Sawyer Audrey H. , Soltanian Mohamad Reza
Published: May 2019

Rivers and their hyporheic zones play an important role in nutrient cycling. The fate of dissolved inorganic nitrogen is governed by reactions that occur in the water column and streambed sediments. Sediments are heterogeneous both in term of physical (e.g., hydraulic conductivity) and chemical (e.g., organic carbon content) properties, which influence water residence times and biogeochemical reactions. Yet few modeling studies have explored the effects of both physical and chemical heterogeneity on nutrient transport in the hyporheic zone. In this study, we simulated hyporheic exchange in physically and chemically heterogeneous sediments with binary distributions of sand and silt in a low‐gradient meandering river. We analyzed the impact of different silt/sand patterns on dissolved organic carbon, oxygen, nitrate, and ammonium. Our results show that streambeds with a higher volume proportion of silt exhibit lower hyporheic exchange rates but more efficient nitrate removal along flow paths compared to predominantly sandy streambeds. The implication is that hyporheic zones with a mixture of inorganic sands and organic silts have a high capacity to remove nitrate, despite their moderate permeabilities.
Evaporation Suppression From Water Bodies Using Floating Covers: Laboratory Studies of Cover Type, Wind, and Radiation Effects
Authors: Lehmann Peter , Aminzadeh Milad , Or Dani
Published: May 2019

Water reservoirs have been used to mitigate seasonal water shortages since the dawn of civilization. Present day use of water reservoirs continues to expand to meet the increasing demand for irrigation water and to mitigate effects of climate change and droughts. Losses to evaporation are an important challenge to water storage efficiency in arid regions. We study the use and efficiency of self‐assembling floating covers as a simple and scalable solution to evaporation suppression. We report laboratory‐scale studies of evaporation suppression using different cover types under various external conditions that jointly affect surface flux partitioning. Experiments using floating spheres and disks of different colors, sizes, and materials were conducted for a range of external conditions (radiation, wind, and wind + radiation) over a 1.44 m2 water basin placed in a wind tunnel. Considering maximum cover density using spherical and disk‐shaped elements (91% surface cover), the evaporation was suppressed by 80% (for disks) and 70% (for spheres) relative to uncovered water surfaces in agreement with physically based model estimates. Surprisingly, evaporation suppression using black and white floating covers was similar despite significantly different surface energy partitioning pathways. The observed similarity was attributed to thermal decoupling between the top of cover elements and water surfaces. The study shows a high and nearly constant evaporation suppression efficiency of floating covers for a range of external conditions supporting the potential of such simple and scalable solution of evaporation suppression for regions with limited infrastructure or alternative water solutions.
Quantifying Process Connectivity With Transfer Entropy in Hydrologic Models
Authors: Bennett Andrew , Nijssen Bart , Ou Gengxin , Clark Martyn , Nearing Grey
Published: May 2019

Quantifying the behavior and performance of hydrologic models is an important aspect of understanding the underlying hydrologic systems. We argue that classical error measures do not offer a complete picture for building this understanding. This study demonstrates how the information theoretic measure known as transfer entropy can be used to quantify the active transfer of information between hydrologic processes at various timescales and facilitate further understanding of the behavior of these systems. To build a better understanding of the differences in dynamics, we compare model instances of the Structure for Unifying Multiple Modeling Alternatives (SUMMA), the Variable Infiltration Capacity (VIC) model, and the Precipitation Runoff Modeling System (PRMS) across a variety of hydrologic regimes in the Columbia River Basin in the Pacific Northwest of North America. Our results show differences in the runoff of the SUMMA instance compared to the other two models in several of our study locations. In the Snake River region, SUMMA runoff was primarily snowmelt driven, while VIC and PRMS runoff was primarily influenced by precipitation and evapotranspiration. In the Olympic mountains, evapotranspiration interacted with the other water balance variables much differently in PRMS than in VIC and SUMMA. In the Willamette River, all three models had similar process networks at the daily time scale but showed differences in information transfer at the monthly timescale. Additionally, we find that all three models have similar connectivity between evapotranspiration and soil moisture. Analyzing information transfers to runoff at daily and monthly time steps shows how processes can operate on different timescales. By comparing information transfer with correlations, we show how transfer entropy provides a complementary picture of model behavior.
Spatial Sequential Modeling and Predication of Global Land Use and Land Cover Changes by Integrating a Global Change Assessment Model and Cellular Automata
Authors: Cao Min , Zhu Yanhui , Quan Jinling , Zhou Sheng , Lü Guonian , Chen Min , Huang Mengxue
Published: May 2019

Characterizing land use and land cover change (LUCC) is critical for understanding the interaction between human activities and global environmental changes, such as in biological diversity and the carbon cycle. Both natural cycles and human activities can be better examined with more accurate sources of land use data with higher spatial resolution. More importantly, it is crucial to consider spatial heterogeneity to simulate future changes in LUCC. In this paper, a modeling strategy (hereinafter referred to as GCAM‐CA) that combines a global change assessment model (GCAM) with cellular automata (CA) is proposed. This modeling strategy is designed to sequentially spatialize global LUCCs with 1‐km spatial resolution and 5‐year temporal resolution from 2010 to 2100. The GCAM model is employed to predict the land use and land cover area demands for 283 world regions, which are divided by intersecting 32 geopolitical and socioeconomic regions and 18 agroecological zones. The spatialization rules of CA is trained separately for each world region to distinguish global land use and land cover types. The different spatialization rules and trends in land use and land cover demand for each of the 283 regions reflect the spatial heterogeneity in the GCAM‐CA model. We implement and validate the model for the simulation from 2000 to 2010. Next, the model is used to simulate three future scenarios, REF, G26, and G45, demonstrating that the GCAM‐CA model is effective for future global‐scale simulation of LUCCs. GCAM‐CA is freely available at the open geographic modeling and simulation platform (OpenGMS, http://geomodeling.njnu.edu.cn/GCAM‐CA.jsp).
Toward a Resilient Global Society: Air, Sea Level, Earthquakes, and Weather
Authors: Anenberg Susan C. , Dutton Andrea , Goulet Christine A. , Swain Daniel L. , van der Pluijm Ben
Published: May 2019

Society's progress along the four corners of prepare, absorb, respond and adapt resilience square is uneven, in spite of our understanding of the foundational science and a growing sense that urgent action is needed. The resilience vignettes describe the meaning and impact of current and near‐term change in four major domains: human health impacts from air pollution, coastal inundation from sea‐level rise, damaging earthquakes in populated areas, and impacts from extreme precipitation. Given our understanding of the scientific principles, societal action, from preparation to adaption, will be critical in minimizing the negative impacts of change. The unprecedented rates of change in today's Earth system argue for urgent action in support of a resilient global society.
New Eyes on Wildfires
Authors: Kelvey Jon
Published: May 2019

Onboard machine learning and compact thermal imaging could turn satellites into real-time fire management tools to help officials on the ground.
Ural Blocking as a Driver of Early‐Winter Stratospheric Warmings
Authors: Peings Y.
Published: May 2019

This study explores the early‐winter atmospheric response to Ural blocking anomalies in November, using a nudging technique to constrain the temperature and dynamics in a high‐top atmospheric model. Persistent Ural blocking anomalies in November are associated with a warm Arctic/cold Siberia pattern and increased upward planetary waves entering the stratosphere, leading to a warming of the polar vortex. This stratospheric response then propagates in the troposphere, leading to increased occurrence of the negative North Atlantic Oscillation in December and January. In contrast, simulations with perturbed Barents‐Kara sea ice and Siberian snow in November do not reproduce a significant atmospheric response. In simulations including a slab ocean, the Ural blocking induces Barents‐Kara sea ice and Siberia snow anomalies that resemble composite analyses from observations. These results highlight Ural blocking variability in November as a robust driver of early‐winter stratospheric warming while questioning causality between sea ice/snow and Ural blocking anomalies.
Lake Water Depth Controlling Archaeal Tetraether Distributions in Midlatitude Asia: Implications for Paleo Lake‐Level Reconstruction
Authors: Wang H. , He Y. , Liu W. , Zhou A. , Kolpakova M. , Krivonogov S. , Liu Z.
Published: May 2019

Lake‐level reconstructions, related to terrestrial hydrological changes, are important for our understanding of past and future climates. Currently, however, reliable lake‐level proxies are still limited. Here we report distributions of archaeal tetraether lipids in 70 surface sediment samples collected from 55 lakes in midlatitude Asia. We have found that among various lake physico‐chemical characteristics, the relative abundances of crenarchaeol and Hydroxylated isoprenoid glycerol dialkyl glycerol tetraethers (%cren and %OH‐GDGTs) are best correlated with lake water depth, due to a preference of Thaumarchaeota, the producer of these biomarkers, for a niche in subsurface lake water. This supports the recent hypothesis based on single‐lake investigations that %cren and %OH‐GDGTs are potentially novel lake‐level proxies. Our results also suggest that %OH‐GDGTs is less affected by soil input than %cren. Nevertheless, other confounding factors should be well constrained and local/site‐specific calibrations are needed before the two molecular proxies are used quantitatively in down‐core applications.