bluuebunny/crossref_metadata_2025 huggingface dataset:
Global warming projections derived from an observation-based minimal model
Authors: Rypdal K.
Published: January 2016

Abstract. A simple conceptual model for the global mean surface temperature (GMST) response to CO2 emissions is presented and analysed. It consists of linear long-memory models for the GMST anomaly response ΔT to radiative forcing and the atmospheric CO2-concentration response ΔC to emission rate. The responses are connected by the standard logarithmic relation between CO2 concentration and its radiative forcing. The model depends on two sensitivity parameters, αT and αC, and two "inertia parameters," the memory exponents βT and βC. Based on observation data, and constrained by results from the Climate Model Intercomparison Project Phase 5 (CMIP5), the likely values and range of these parameters are estimated, and projections of future warming for the parameters in this range are computed for various idealised, but instructive, emission scenarios. It is concluded that delays in the initiation of an effective global emission reduction regime is the single most important factor that influences the magnitude of global warming over the next 2 centuries. The most important aspect of this study is the simplicity and transparency of the conceptual model, which makes it a useful tool for communicating the issue to non-climatologists, students, policy makers, and the general public.
Linking snow depth to avalanche release area size: Measurements from the Vallée de la Sionne fieldsite
Authors: Veitinger J. , Sovilla B.
Published: January 2016

Abstract. One of the major challenges in avalanche hazard assessment is the correct estimation of avalanche release area size which is of crucial importance to evaluate the potential danger that avalanches pose to roads, railways or infrastructure. The assessment of potential release area size is nowadays mainly based on terrain analysis; however, it is assumed that with increasing snow accumulation and the attenuation of terrain irregularities larger release areas may form. To investigate this hypothesis, the relation between avalanche release area size, snow depth and surface roughness was investigated using avalanche observations of artificially triggered slab avalanches over a period of 15 years in a high-alpine fieldsite. High resolution, continuous snow depth measurements at times of avalanche release showed a decrease of mean surface roughness with increasing release area size both for the bed surface and the snow surface before avalanche release. Further, surface roughness patterns in snow covered winter terrain appeared to be well suited to demarcate release areas, suggesting an increase of potential release area size with greater snow depth. In this context, snow depth around terrain features that serve as potential delineation borders, such as ridges or trenches, appeared to be particularly relevant for release area size. Furthermore, snow depth measured at a nearby weather station was to a considerable extent related to potential release area size, as it was often representative for snow depth around those critical features where snow can accumulate over a long period before becoming susceptible for avalanche release. Snow depth – due to its link to surface roughness – could therefore serve as a highly useful variable with regard to potential release area definition for varying snow cover scenarios, as for example, the avalanche hazard assessment for transport ways or ski resorts.
Surface Energy Balance Sensitivity to Meteorological Variability on Haig Glacier, Canadian Rocky Mountains
Authors: Ebrahimi S. , Marshall S. J.
Published: January 2016

Abstract. Energy exchanges between the atmosphere and the glacier surface control the net energy available for snow and ice melt. Meteorological and glaciological observations are not always available to measure glacier energy and mass balance directly, so models of energy balance processes are often necessary to understand glacier response to meteorological variability and climate change. This paper explores the theoretical and empirical response of a mid-latitude glacier in the Canadian Rocky Mountains to the daily and interannual variations in the meteorological parameters that govern the surface energy balance. The model's reference conditions are based on 11 years of in situ observations from an automatic weather station at an elevation of 2660 m, in the upper ablation area of Haig Glacier. We use an energy balance model to run sensitivity tests to perturbations in temperature, specific humidity, wind speed, incoming shortwave radiation, and glacier surface albedo. The variables were perturbed one at a time for the duration of the glacier melt season, May to September, for the years 2002–2012. The experiments indicate that summer melt has the strongest sensitivity to interannual variations in incoming shortwave radiation, albedo, and temperature, in that order. To explore more realistic scenarios where meteorological variables and internal feedbacks such as the surface albedo co-evolve, we use the same perturbation approach using meteorological forcing from the North American Regional Reanalysis (NARR) over the period 1979–2014. These experiments provide an estimate of historical variability in Haig Glacier surface energy balance an d melt for years prior to our observational study. The methods introduced in this paper provide a methodology that can be employed in distributed energy balance modelling at regional scales. They also provide the foundation for theoretical framework that can be adapted to compare the climatic sensitivity of glaciers in different climate regimes, e.g., polar, maritime, or tropical environments.
Análisis de discurso a medios de comunicación digitales en Chile respecto al cambio climático: encuadres para la construcción de las agendas públicas y política
Authors: Hasbún Julio
Published: January 2016

Este estudio de caso busca conocer cómo los medios digitales representan el cambio climático en Chile, poniendo énfasis en la mitigación, adaptación y resiliencia. Se realizó un análisis de contenido a los cuatro medios digitales con mayor lectoría en Chile (2 liberales y 2 conservadores), durante el período que va desde la Segunda Comunicación Nacional de Cambio Climático (30/08/11) hasta la inauguración del Centro de Ciencia del Clima y la Resiliencia (31/10/13), con el fin de conocer los encuadres y narrativas predominantes en las noticias de cambio climático en Chile. Se obtuvo un corpus de 58 noticias nacionales, sobre el que se llevó a cabo un análisis de discurso crítico para comprender la presencia o ausencia de actores y narrativas, y así visibilizar las relaciones de poder. Los hallazgos más relevantes del análisis de contenido apuntan a: (i) bajo número de noticias de cambio climático en Chile (14,83%) en relación a las internacionales; (ii) a que los definidores primarios del tema son los actores gubernamentales; (iii) y a la invisibilización de las personas y organizaciones ciudadanas.
Rediseño del modelo de defensa penitenciaria para adultos privados de libertad en el nuevo sistema procesal penal
Authors: Lidebinsky Sofía
Published: January 2016

El presente estudio de caso tiene como objeto central rediseñar aspectos del “Programa de Defensa Penal Pública Penitenciaria” a partir de un análisis de su diseño original y funcionamiento actual, utilizando la metodología de marco lógico. La pregunta de investigación busca revisar si este programa contribuye a fortalecer el acceso a la justicia de las personas condenadas privadas de libertad. El estudio se desarrolló a través de la realización y posterior análisis de entrevistas a los actores claves del programa provenientes de la Defensoría Penal Pública y de Gendarmería de Chile. La visión de ambas instituciones resulta fundamental en la detección de los problemas y aciertos en la implementación del programa a fin de poder proponer algunos cambios y mejoras. Asimismo, se realizó un taller con condenados y se analizaron entrevistas de percepción de usuarios en las tres regiones en funcionamiento, con el propósito de poder contar con la percepción de los beneficiarios de este programa.
Una política pública para el desarrollo del capital humano de funcionarios municipales: aprendizajes para el caso de la Academia de Capacitación Municipal y Regional
Authors: Rebolledo Edgar
Published: January 2016

Este estudio desarrolló un exhaustivo análisis de la experiencia internacional, a fin de dilucidar las distintas estrategias, abordadas por tres escuelas de formación de funcionarios públicos, en el desarrollo del capital humano dentro de la Administración Pública de sus respectivos países, y contrastar dicha experiencia con el caso chileno, dándole especial atención a la formación y capacitación de los funcionarios de gobiernos locales. Se propone que, a raíz de la nueva Ley, la institucionalidad de la Academia de Formación debe articular esfuerzos, recursos, actores y voluntades, a fin de que la formación y capacitación entregada por la Academia esté asociada al ascenso, aumento de grados y sean prioridad para el reclutamiento y selección, para cubrir cargos disponibles en las municipalidades que ingresen al sistema, tal como ocurre con las escuelas internacionales estudiadas.
Approximate Inertial Coordinate System Selections for Rotation Problems - The Gravitational Field of the Celestial Body Higher than the Object Being Rotated
Authors: Li Zifeng
Published: January 2016

Selection of the coordinate system is essential for rotation problems. Otherwise, mistakes may occur due to inaccurate measurement of angular speed. Approximate inertial coordinate system selections for rotation problems should be the gravitational field of the celestial body higher than the object being rotated: (1) the Earth fixed Cartesian coordinate system for normal rotation problem; (2) heliocentric - geocentric Cartesian coordinate system for satellites orbiting the Earth; (3) the Galaxy Heart - heliocentric Cartesian coordinates for Earth's rotation around the Sun. In astrophysics, mass calculation error and angular velocity measurement error lead to a black hole conjecture.
Comprehensive Analysis of the Failure of Intuition in Elementary Rigid Body Dynamics
Authors: Ricardo Bernard
Published: January 2016

This article provides a thorough and comprehensive analysis of an elementary problem in rigid body dynamics, involving a projectile and a rod on a smooth table. The problem presented is an extension of a problem taken from an undergraduate physics textbook. This paper presents some generalisations to the problem, namely the unevenness (non-uniformity) of the rod’s mass distribution, the elasticity of the collision, and the case where the rod is pivoted. This paper presents nice analytical steps that address some misconceptions in students’ way of thinking as well as the failure of intuition when it comes to solving physics problems which necessarily require mathematical approach. The result is quite surprising and counterintuitive as it goes against our intuition with daily experience involving doors and levers.
Parity Indices and Two-Line Matrix Representation for Partitions
Authors: Craveiro Irene Magalhães , Wagner Adriana , Domingues Deborah
Published: January 2016

In this work we present a solution for Andrews's Problem 5 [1], by establishing a bijection between the sets and defined in Fine's Theorem [8] and the sets of partitions indexed by their lower parity index [1]. We provide two combinatorial interpretations for [1], determining another solution for Problem 5. We also solve Andrews's Problem 6, conjectured in [1].
Feature Extraction of Structures in Sea Water Using Self-Organizing Maps and Electromagnetic Waves
Authors: Silva Murilo Teixeira , Batista Lurimar Smera , De Albuquerque Frederico Medeiros Vasconcelos
Published: January 2016

The use of Self-Organizing Map (SOM) algorithm for feature extraction and dimensionality reduction applied to underwater object detection with Low Frequency Electromagnetic Waves is presented. Computer simulation is used to generate a direct model for the study region, and a Self Organizing Map Algorithm is used to fit the data and return a similar model, with smaller dimensionality and same characteristics. Results show that virtual sensors are created by the SOM algorithm with consistent predictions, filling the resolution gap of the input data. These results are useful for fastening decision making algorithms by reducing the number of inputs to a group of significant data.
Preliminary studies of fungi in the Biebrza National Park. Part IV. Macromycetes – new data and the synthesis
Authors: Kujawa Anna , Gierczyk Błażej , Domian Grażyna , Wrzosek Marta , Stasińska Małgorzata , Szkodzik Jarosław , Leski Tomasz , Karliński Leszek , Pietras Marcin , Dynowska Maria , Henel Agnieszka , Ślusarczyk Dominika , Kubiak Dariusz
Published: January 2016

The paper presents the last part of the results of the short-term inventory of fungi species in the Biebrza National Park and synthesises all the data gathered during two surveys, including the information published by other authors. The main body of research is focused on a survey of macrofungi identified with morphology-based methods. In case of some specimens molecular technics have been applied. In total 346 macrofungal taxa (21 belonging to ascomycetes and 325 to basidiomycetes) were found during the survey, including 186 species unobserved during the previous inventory in 2012. As a result of previous and ongoing studies, the current number of macrofungi recorded from the Biebrza National Park reached 508 species. Among them eight taxa are newly reported for Poland (Conocybe velutipes var. nitrophila, Entoloma caeruleum, E. plebejoides, Inocybe rennyi, I. vulpinella, Pholiota pityrodes, Pholiotina utricystidiata, and Tomentella pilosa). The next seven species (Bovista paludosa, Fistulina hepatica, Ganoderma lucidum, Geastrum schmidelii, Inonotus obliquus, Tulostoma kotlabae, and Xerocomus parasiticus) are protected by law and 95 species belong to red-listed species. The results of two intensive, but relatively short-term survey clearly indicate the Biebrza National Park as a hot spot of macrofungi and suggest the need to undertake extended and regular inventories also in other Polish national parks.
Preparation and Characteristics of a Novel Sorptive Extraction Stir Bar Based on Cd-Imprinted Polymer Monoliths
Authors: Wang Shiru , Wang Sui
Published: January 2016

A novel monolithic stir-bar for Cd(II) sorption extraction was prepared by ion-imprinting technology and in situ stepwise polymerization of epoxy resin (EP). The condensation product of diethylenetriamine and thiourea (DETATUC) was used as a curing agent, with Cd ions as template ions and polyethylene glycol 1540 as a porogenic agent. The main parameters of the stir-bar sorption extraction-EP-DETATUC material for the extraction and desorption of Cd(II) in aqueous solution were investigated, and inductively coupled plasma-atomic emission spectrometry was performed. The results showed that the monolithic material possessed good permeability and reusability. The maximum adsorption capacity was 136.58 μmol g−1 at pH 6.0. The optimized conditions were the following: stirring rate at 300 rpm, adsorption time at 40 min, elution media at 0.25 mol L−1 EDTA, and elution time at 20 min. The accuracy of the method was assessed by spiking two water samples and one plant sewage sample with Cd at two concentration levels. Recoveries of 96–102% were obtained.
Determination of Chloride in Infant Formula and Adult/Pediatric Nutritional Formula by Potentiometric Titration: Single-Laboratory Validation, First Action 2015.07
Authors: Bolong Wu , Fengxia Zhang , Xiaoning Ma , Fengjuan Zhou , Brunelle Sharon L
Published: January 2016

A potentiometric method for determination of chloride was validated against AOAC Standard Method Performance Requirement (SMPR®) 2014.015. Ten AOAC Stakeholder Panel on Infant Formula and Adult Nutritionals (SPIFAN) matrixes, including National Institute of Standards and Technology (NIST) Standard Reference Material (SRM) 1849a, were tested in duplicate on 6 independent days. The repeatability (RSDr) ranged from 0.43 to 1.34%, and the intermediate reproducibility (RSDiR) ranged from 0.80 to 3.04%. All results for NIST SRM 1849a were within the range of the certified concentration (701 ± 17 mg/100 g). Recovery was demonstrated with two overspike levels, 50 and 100%, in the 10 SPIFAN matrixes. Samples were tested in duplicate on 3 different days, and all results were within the SMPR requirement of 95 to 105%. The LOQs of the method for powdered products and ready-to-feed or reconstituted products were 20 mg/100 g and 2.2 mg/100 mL, respectively. A wide analytical range from the LOQ to 99.5% chlorine content can be reached with an appropriate dilution factor, but in practice, the upper analytical value observed in routine matrix testing was approximately 1080 mg/100 g in skim milk powder. This is a rapid, simple, and reliable chlorine-testing method applicable to infant formula, adult nutritionals, and ingredients used in these dairy-based products, such as skim milk powder, desalted whey powder, whey protein powder, and whole milk powder.
Un territoire de cent pas de côté : récits de la création d’une réserve indienne en territoire innu au milieu du XXe siècle1
Authors: Maltais-Landry Aude
Published: January 2016

Cet article se base sur des récits recueillis dans le cadre d’un projet de recherche en histoire orale mené avec des membres de la communauté innue de Nutashkuan, sur la Côte-Nord, et qui portait sur la création de leur réserve dans les années 1950. Il se veut un exemple d’une utilisation possible de l’histoire orale où les récits, placés au coeur de la trame narrative, permettent d’écrire une histoire des Autochtones qui soit portée par leur propre compréhension des événements. Au-delà de leur ancrage dans des lieux très précis, les récits présentés ici ouvrent la porte à une histoire plus vaste de l’imposition de la Loi sur les Indiens aux communautés autochtones du Québec.
« Au-delà du syndrome de la ‘‘citation payante’’ » : les archives vivantes et la recherche réciproque en histoire orale1
Authors: High Steven , McNeil Françoise
Published: January 2016

Les organismes subventionnaires nord-américains et européens se sont engagés à promouvoir une culture de partage des données qualitatives et ce changement de perspective a suscité des controverses dans certaines disciplines, en particulier dans les cas où la propriété intellectuelle et l’identité disciplinaire reposent sur le travail de terrain plutôt que sur une réutilisation ou une analyse secondaire des données récoltées par d’autres chercheurs. Cet article vise principalement la valeur interprétative et créative des bases de données numériques d’histoire orale, ou archives vivantes, ainsi que leur valeur publique ou politique. Les archives d’histoire orale doivent être des sites de circulation de données et de conservation numérique ainsi que des dépôts dynamiques visant la préservation à long terme.
Le contentieux de la Cour supérieure, 1880-1890 : droit, marché et société durant la transition au capitalisme industriel
Authors: Nootens Thierry
Published: January 2016

Dans un article précédent, nous avons analysé la condition socioprofessionnelle des demandeurs et défendeurs impliqués dans les litiges entendus par la Cour supérieure dans le district de Trois-Rivières, durant la décennie 18801. Il s’agit maintenant d’examiner plus précisément l’éventail de ces affaires. Les conflits mettant en scène deux groupes spécifiques, soit les cultivateurs et les industriels, sont aussi mis en relief. Ce faisant, nous serons en mesure d’établir si le monde de la terre et l’entrepreneuriat capitaliste présentent un rapport au droit très spécifique à l’époque considérée. La question des interactions entre droit positif et expérience ordinaire du droit est abordée en conclusion générale.
Les perspectives humaniste et politique sur les droits humains
Authors: Gilabert Pablo , Bandini Aude
Published: January 2016

Cet article s’intéresse au lien entre deux perspectives qui concernent la nature des droits humains. Selon la perspective « politique » ou « pratique », les droits humains sont des revendications que les individus entretiennent face à un certain nombre de structures institutionnelles, dans certains États modernes, en vertu des intérêts qui sont les leurs selon les contextes qui les mettent en jeu. Selon la perspective « humaniste » ou « naturaliste », plus traditionnelle, les droits humains sont des revendications pré-institutionnelles que les individus entretiennent face à tous les autres individus, en vertu d’intérêts propres à l’humanité qu’ils ont tous en partage. Cet article soutient qu’une fois qu’on identifie ces deux perspectives sous leur meilleur jour, on peut voir qu’elles sont complémentaires et qu’on a en réalité besoin de chacune d’elles pour donner sens, sur le plan normatif, à la pratique contemporaine des droits humains. J’y explique comment des considérations humanistes et politiques peuvent et même doivent travailler main dans la main si on veut rendre compte du concept, du contenu et de la justification des droits humains.
FORMAÇÃO DE PROFESSORES (DE MATEMÁTICA): TEXTOS E CONTEXTOS DE UMA CAMPANHA
Authors: Baraldi Ivete Maria , Gaertner Rosinéte
Published: January 2016

Neste artigo apresentamos traços históricos gerais sobre a Campanha de Aperfeiçoamento e Difusão do Ensino Secundário (Cades) e sobre suas publicações. De total desconhecida à multifacetada, a Cades mostrou-se como um importante veículo dos ideais da época, décadas de 1950 e 1960, no que diz respeito à formação de professores e uma maneira dos docentes se aperfeiçoarem, discutirem e formalizarem sua prática quando ainda, no Brasil, era raro um lócus para tal exercício. Essa Campanha, até os dias atuais, foi quase que totalmente ignorada pelos pesquisadores da História da Educação (Matemática), o que nos leva a acreditar que, muitas vezes, quando se estuda a formação de professores, se adota uma postura elitista e centralizadora, focando somente os grandes centros e partindo de instituições de ensino consideradas tradicionais.
UM RELATO DE VIVÊNCIA DA UTILIZAÇÃO DO SOFTWARE MODELLUS E DE MAPAS CONCEITUAIS NO ENSINO DE FÍSICA
Authors: Oliveira Humberto Da Silva , Freire Morgana Ligia de Farias , Moita Filomena Maria G. da S. Cordeiro
Published: January 2016

Este texto tem como objetivo relatar uma vivência em sala de aula, feita na tentativa de aplicar a Teoria da Aprendizagem significativa de Ausubel, utilizando o software Modellus, em conjunto com a aplicação de mapas conceituais no estudo do movimento dos projéteis. Foi aplicado em uma turma do 1º ano do ensino médio, seguindo-se as orientações do PCN+ para o ensino de Física. Os resultados revelaram que a abordagem utilizada no processo de ensino e aprendizagem, para a apresentação do conteúdo, possibilitou uma participação mais ativa dos alunos, que demonstraram interesse e curiosidade em manusear o computador para explorar os conceitos estudados em sala de aula.
EXPLORANDO A IDEIA DE ACASO NOS FENÔMENOS ALEATÓRIOS, A PARTIR DE UMA SEQUÊNCIA DE ENSINO
Authors: Vargas Saulo , Moretto Geraldo
Published: January 2016

Este artigo apresenta os resultados de uma pesquisa de mestrado, e seu objetivo é mostrar uma sequência de ensino que explore a ideia de acaso nos fenômenos aleatórios. Essa sequência de ensino é constituída de um questionário aberto para investigar como os alunos consideram o acaso nos eventos aleatórios e de quatro atividades para explorar a ideia de acaso em experimentos aleatórios. A sequência foi aplicada com alunos dos cursos superiores de Biologia e Medicina Veterinária. Com base nos resultados da sequência de ensino, constatou-se que houve uma melhora significativa na concepção dos alunos de como consideram o acaso nos fenômenos aleatórios.
ECOFORMAÇÃO E TRANSDISCIPLINARIDADE NA REDE DE ESCOLAS CRIATIVAS
Authors: De La Torre Saturnino , De Souza e Silva Vera Lúcia
Published: January 2016

A transformação da prática educativa em convergência com as necessidades de sustentabilidade planetária e o estímulo a relações de convivência solidária e criativa são aspectos fundamentais em projetos de instituições educativas preocupadas em qualificar a vida no planeta. Nesta perspectiva baseia-se o Programa Institucional Rede de Escolas Criativas-RIEC, que objetiva auxiliar profissionais da educação em busca de práticas educativas que contemplem a ecoformação e a transdisciplinaridade. A experiência apresentada neste trabalho, concebida como uma possibilidade de ação em rede para promoção de ensino, pesquisa e extensão é reflexo de implementações de propósitos realizados pelos membros da RIEC.
A MATLAB toolbox and Excel workbook for calculating the densities, seismic wave speeds, and major element composition of minerals and rocks at pressure and temperature
Authors: Abers Geoffrey A. , Hacker Bradley R.
Published: January 2016

To interpret seismic images, rock seismic velocities need to be calculated at elevated pressure and temperature for arbitrary compositions. This technical report describes an algorithm, software, and data to make such calculations from the physical properties of minerals. It updates a previous compilation and Excel® spreadsheet and includes new MATLAB® tools for the calculations. The database of 60 mineral end‐members includes all parameters needed to estimate density and elastic moduli for many crustal and mantle rocks at conditions relevant to the upper few hundreds of kilometers of Earth. The behavior of α and β quartz is treated as a special case, owing to its unusual Poisson's ratio and thermal expansion that vary rapidly near the α‐β transition. The MATLAB tools allow integration of these calculations into a variety of modeling and data analysis projects.
Alignment between seafloor spreading directions and absolute plate motions through time
Authors: Williams Simon E. , Flament Nicolas , Müller R. Dietmar
Published: January 2016

The history of seafloor spreading in the ocean basins provides a detailed record of relative motions between Earth's tectonic plates since Pangea breakup. Determining how tectonic plates have moved relative to the Earth's deep interior is more challenging. Recent studies of contemporary plate motions have demonstrated links between relative plate motion and absolute plate motion (APM), and with seismic anisotropy in the upper mantle. Here we explore the link between spreading directions and APM since the Early Cretaceous. We find a significant alignment between APM and spreading directions at mid‐ocean ridges; however, the degree of alignment is influenced by geodynamic setting, and is strongest for mid‐Atlantic spreading ridges between plates that are not directly influenced by time‐varying slab pull. In the Pacific, significant mismatches between spreading and APM direction may relate to a major plate‐mantle reorganization. We conclude that spreading fabric can be used to improve models of APM.
The impact of an ICME on the Jovian X‐ray aurora
Authors: Dunn William R. , Branduardi‐Raymont Graziella , Elsner Ronald F. , Vogt Marissa F. , Lamy Laurent , Ford Peter G. , Coates Andrew J. , Gladstone G. Randall , Jackman Caitriona M. , Nichols Jonathan D. , Rae I. Jonathan , Varsani Ali , Kimura Tomoki , Hansen Kenneth C. , Jasinski Jamie M.
Published: January 2016

We report the first Jupiter X‐ray observations planned to coincide with an interplanetary coronal mass ejection (ICME). At the predicted ICME arrival time, we observed a factor of ∼8 enhancement in Jupiter's X‐ray aurora. Within 1.5 h of this enhancement, intense bursts of non‐Io decametric radio emission occurred. Spatial, spectral, and temporal characteristics also varied between ICME arrival and another X‐ray observation two days later. Gladstone et al. (2002) discovered the polar X‐ray hot spot and found it pulsed with 45 min quasiperiodicity. During the ICME arrival, the hot spot expanded and exhibited two periods: 26 min periodicity from sulfur ions and 12 min periodicity from a mixture of carbon/sulfur and oxygen ions. After the ICME, the dominant period became 42 min. By comparing Vogt et al. (2011) Jovian mapping models with spectral analysis, we found that during ICME arrival at least two distinct ion populations, from Jupiter's dayside, produced the X‐ray aurora. Auroras mapping to magnetospheric field lines between 50 and 70 RJ were dominated by emission from precipitating sulfur ions (S7+,…,14+). Emissions mapping to closed field lines between 70 and 120 RJ and to open field lines were generated by a mixture of precipitating oxygen (O7+,8+) and sulfur/carbon ions, possibly implying some solar wind precipitation. We suggest that the best explanation for the X‐ray hot spot is pulsed dayside reconnection perturbing magnetospheric downward currents, as proposed by Bunce et al. (2004). The auroral enhancement has different spectral, spatial, and temporal characteristics to the hot spot. By analyzing these characteristics and coincident radio emissions, we propose that the enhancement is driven directly by the ICME through Jovian magnetosphere compression and/or a large‐scale dayside reconnection event.
Using a genetic algorithm to estimate the details of earthquake slip distributions from point surface displacements
Authors: Lindsay A. , McCloskey J. , Nic Bhloscaidh M.
Published: January 2016

Examining fault activity over several earthquake cycles is necessary for long‐term modeling of the fault strain budget and stress state. While this requires knowledge of coseismic slip distributions for successive earthquakes along the fault, these exist only for the most recent events. However, overlying the Sunda Trench, sparsely distributed coral microatolls are sensitive to tectonically induced changes in relative sea levels and provide a century‐spanning paleogeodetic and paleoseismic record. Here we present a new technique called the Genetic Algorithm Slip Estimator to constrain slip distributions from observed surface deformations of corals. We identify a suite of models consistent with the observations, and from them we compute an ensemble estimate of the causative slip. We systematically test our technique using synthetic data. Applying the technique to observed coral displacements for the 2005 Nias‐Simeulue earthquake and 2007 Mentawai sequence, we reproduce key features of slip present in previously published inversions such as the magnitude and location of slip asperities. From the displacement data available for the 1797 and 1833 Mentawai earthquakes, we present slip estimates reproducing observed displacements. The areas of highest modeled slip in the paleoearthquake are nonoverlapping, and our solutions appear to tile the plate interface, complementing one another. This observation is supported by the complex rupture pattern of the 2007 Mentawai sequence, underlining the need to examine earthquake occurrence through long‐term strain budget and stress modeling. Although developed to estimate earthquake slip, the technique is readily adaptable for a wider range of applications.
The rock physics and geochemistry of carbonates exposed to reactive brines
Authors: Clark Anthony C. , Vanorio Tiziana
Published: January 2016

When carbonate‐rich rocks are brought into contact with an acidic brine their mechanical and acoustic responses depend on many factors including pH, porosity, permeability, effective stress, and time. These complexities hinder the understanding of processes such as hydrothermal fluid circulation, seismicity, and deep burial diagenesis. The present study addresses how different lithofacies exposed to the same reactive brine undergo varying degrees of transformation and whether it is possible to remotely detect these phenomena in the Earth. Results are presented from fluid injections carried out on a large and varied set of calcareous rocks under hydrostatic stress. The output brine was analyzed for dissolved mineral concentrations and the rock porosity, permeability, axial strain, ultrasonic velocity, and images from electron microscopy were contrasted before and after injection. Microbialites were found to be the lithofacies most vulnerable to changes in their transport properties. However, all samples irreversibly compacted with the greatest strain in the most porous and permeable cores. The most extreme structural changes discovered through imaging were the welding of microporous zones, grain sliding, and the fracturing of various phases. Observations are consistent with a chemically enhanced weakening of the rock frame that generated compliant pores. The associated decrease in velocity of the dry rock can be approximated with linear relations that depend on both porosity and effective stress.
The characteristics and dynamics of wave‐driven flow across a platform coral reef in the Red Sea
Authors: Lentz S. J. , Churchill J. H. , Davis K. A. , Farrar J. T. , Pineda J. , Starczak V.
Published: January 2016

Current dynamics across a platform reef in the Red Sea near Jeddah, Saudi Arabia, are examined using 18 months of current profile, pressure, surface wave, and wind observations. The platform reef is 700 m long, 200 m across with spatial and temporal variations in water depth over the reef ranging from 0.6 to 1.6 m. Surface waves breaking at the seaward edge of the reef cause a 2–10 cm setup of sea level that drives cross‐reef currents of 5–20 cm s−1. Bottom stress is a significant component of the wave setup balance in the surf zone. Over the reef flat, where waves are not breaking, the cross‐reef pressure gradient associated with wave setup is balanced by bottom stress. The quadratic drag coefficient for the depth‐average flow decreases with increasing water depth from Cda = 0.17 in 0.4 m of water to Cda = 0.03 in 1.2 m of water. The observed dependence of the drag coefficient on water depth is consistent with open‐channel flow theory and a hydrodynamic roughness of zo = 0.06 m. A simple one‐dimensional model driven by incident surface waves and wind stress accurately reproduces the observed depth‐averaged cross‐reef currents and a portion of the weaker along‐reef currents over the focus reef and two other Red Sea platform reefs. The model indicates the cross‐reef current is wave forced and the along‐reef current is partially wind forced.
Airborne quantification of upper tropospheric NOx production from lightning in deep convective storms over the United States Great Plains
Authors: Pollack I. B. , Homeyer C. R. , Ryerson T. B. , Aikin K. C. , Peischl J. , Apel E. C. , Campos T. , Flocke F. , Hornbrook R. S. , Knapp D. J. , Montzka D. D. , Weinheimer A. J. , Riemer D. , Diskin G. , Sachse G. , Mikoviny T. , Wisthaler A. , Bruning E. , MacGorman D. , Cummings K. A. , Pickering K. E. , Huntrieser H. , Lichtenstern M. , Schlager H. , Barth M. C.
Published: January 2016

The reported range for global production of nitrogen oxides (NOx = NO + NO2) by lightning remains large (e.g., 32 to 664 mol NOx flash−1), despite incorporating results from over 30 individual laboratory, theoretical, and field studies since the 1970s. Airborne and ground‐based observations from the Deep Convective Clouds and Chemistry experiment in May and June 2012 provide a new data set for calculating moles of NOx produced per lightning flash, P(NOx), in thunderstorms over the United States Great Plains. This analysis utilizes a combination of in situ observations of storm inflow and outflow from three instrumented aircraft, three‐dimensional spatial information from ground‐based radars and satellite observations, and spatial and temporal information for intracloud and cloud‐to‐ground lightning flashes from ground‐based lightning mapping arrays. Evaluation of two analysis methods (e.g., a volume‐based approach and a flux‐based approach) for converting enhancements in lightning‐produced NOx from volume‐based mixing ratios to moles NOx flash−1 suggests that both methods equally approximate P(NOx) for storms with elongated anvils, while the volume‐based approach better approximates P(NOx) for storms with circular‐shaped anvils. Results from the more robust volume‐based approach for three storms sampled over Oklahoma and Colorado during DC3 suggest a range of 142 to 291 (average of 194) moles NOx flash−1 (or 117–332 mol NOx flash−1 including uncertainties). Although not vastly different from the previously reported range for storms occurring in the Great Plains (e.g., 21–465 mol NOx flash−1), results from this analysis of DC3 storms offer more constrained upper and lower limits for P(NOx) in this geographical region.
Surfactant effect on cloud condensation nuclei for two‐component internally mixed aerosols
Authors: Petters Sarah Suda , Petters Markus Dirk
Published: January 2016

This work presents experimental data on the cloud condensation nuclei (CCN) activity of two‐component mixtures containing surfactants. Nine binary systems were tested combining strong ionic (sodium dodecyl sulfate) and nonionic surfactants (Zonyl FS‐300 and Triton X‐100) with nonsurfactant compounds (glucose, ammonium sulfate, or sodium chloride). Control tests were performed for systems combining organic (glucose) and inorganic compounds (ammonium sulfate or sodium chloride). Results show that CCN activity deviates strongly relative to predictions made from measurements of bulk surface tension. Köhler theory accounting for surface tension reduction and surface partitioning underpredicts the CCN activity of particles containing Zonyl FS‐300 and Triton X‐100. Partitioning theory better describes data for Zonyl FS‐300 and Triton X‐100 when limiting surface adsorption to 1.5 monolayers of the growing drop. Deviations from predictions were observed. Likely explanations include solute‐solute interactions and nonspherical particle shape. The findings presented here examine in detail the perturbation of CCN activity by surfactants and may offer insight into both the success and limitations of physical models describing CCN activity of surface active molecules.
Can increasing albedo of existing ship wakes reduce climate change?
Authors: Crook Julia A. , Jackson Lawrence S. , Forster Piers M.
Published: January 2016

Solar radiation management schemes could potentially alleviate the impacts of global warming. One such scheme could be to brighten the surface of the ocean by increasing the albedo and areal extent of bubbles in the wakes of existing shipping. Here we show that ship wake bubble lifetimes would need to be extended from minutes to days, requiring the addition of surfactant, for ship wake area to be increased enough to have a significant forcing. We use a global climate model to simulate brightening the wakes of existing shipping by increasing wake albedo by 0.2 and increasing wake lifetime by ×1440. This yields a global mean radiative forcing of −0.9 ± 0.6 Wm−2 (−1.8 ± 0.9 Wm−2 in the Northern Hemisphere) and a 0.5°C reduction of global mean surface temperature with greater cooling over land and in the Northern Hemisphere, partially offsetting greenhouse gas warming. Tropical precipitation shifts southward but remains within current variability. The hemispheric forcing asymmetry of this scheme is due to the asymmetry in the distribution of existing shipping. If wake lifetime could reach ~3 months, the global mean radiative forcing could potentially reach −3 Wm−2. Increasing wake area through increasing bubble lifetime could result in a greater temperature reduction, but regional precipitation would likely deviate further from current climatology as suggested by results from our uniform ocean albedo simulation. Alternatively, additional ships specifically for the purpose of geoengineering could be used to produce a larger and more hemispherically symmetrical forcing.
Lithospheric flexure and gravity spreading of Olympus Mons volcano, Mars
Authors: Musiol S. , Holohan E. P. , Cailleau B. , Platz T. , Dumke A. , Walter T. R. , Williams D. A. , van Gasselt S.
Published: January 2016

The structural architecture of large volcanoes is governed substantially by gravity‐driven deformation that is manifest as distinct processes such as basement flexure or volcanic spreading. Temporal effects and the mutual interplay of these processes have been investigated only to a limited extent, and so we present novel numerical models of the time‐dependent deformation associated with them. The models simulate the combined effects of lithospheric flexure and volcanic spreading during growth increments of an elastoplastic volcanic cone. Different spreading scenarios are considered by a variable coupling decoupling behavior at the interface between volcano and basement. We apply our models to Olympus Mons on Mars, which is characterized by upper to middle flank terraces on the shield, is encircled by a basal scarp that has an average slope of 30° and is surrounded by distant deposits that resemble large‐scale slumping features on Earth. Our results are consistent with the interpretation that terraces on Olympus Mons' flanks form by thrust faulting that results from lithospheric flexure. The presence and expression of terraces depend on the coupling of volcano and basement, on the time of volcano growth relative to mantle relaxation, and on the cohesion of the edifice. The encircling scarp may be related to a very low friction detachment at the edifice base, which leads to a normal fault regime on the lowermost flanks. With time and volcano growth, predicted stress and faulting regimes migrate only slightly, indicating that the structural architecture of volcanoes is largely set in the very early stages of formation.
Landscape response to late Pleistocene climate change in NW Argentina: Sediment flux modulated by basin geometry and connectivity
Authors: Schildgen Taylor F. , Robinson Ruth A. J. , Savi Sara , Phillips William M. , Spencer Joel Q. G. , Bookhagen Bodo , Scherler Dirk , Tofelde Stefanie , Alonso Ricardo N. , Kubik Peter W. , Binnie Steven A. , Strecker Manfred R.
Published: January 2016

Fluvial fill terraces preserve sedimentary archives of landscape responses to climate change, typically over millennial timescales. In the Humahuaca Basin of NW Argentina (Eastern Cordillera, southern Central Andes), our 29 new optically stimulated luminescence ages of late Pleistocene fill terrace sediments demonstrate that the timing of past river aggradation occurred over different intervals on the western and eastern sides of the valley, despite their similar bedrock lithology, mean slopes, and precipitation. In the west, aggradation coincided with periods of increasing precipitation, while in the east, aggradation coincided with decreasing precipitation or more variable conditions. Erosion rates and grain size dependencies in our cosmogenic 10Be analyses of modern and fill terrace sediments reveal an increased importance of landsliding compared to today on the west side during aggradation, but of similar importance during aggradation on the east side. Differences in the timing of aggradation and the 10Be data likely result from differences in valley geometry, which causes sediment to be temporarily stored in perched basins on the east side. It appears as if periods of increasing precipitation triggered landslides throughout the region, which induced aggradation in the west, but blockage of the narrow bedrock gorges downstream from the perched basins in the east. As such, basin geometry and fluvial connectivity appear to strongly influence the timing of sediment movement through the system. For larger basins that integrate subbasins with differing geometries or degrees of connectivity (like Humahuaca), sedimentary responses to climate forcing are likely attenuated.
Modeling the interference environment in the HF band
Authors: Pederick L. H. , Cervera M. A.
Published: January 2016

The performance of systems using high frequency (HF) radio waves, such as over‐the‐horizon radars (OTHR), can be strongly affected by external interferers at great distances (thousands of kilometers) from the systems receiver. However, the propagation of interference has complex behavior and is known to vary with location, time, season, sunspot number, and radio frequency. Understanding how the level of interference varies with all of these factors is important for the design of new systems such as next generation OTHR. By combining databases of known transmitters, ray‐tracing propagation, and a model ionosphere, a model of the behavior of interference at HF has been developed.
The Longriqu fault zone, eastern Tibetan Plateau: Segmentation and Holocene behavior
Authors: Ansberque Claire , Bellier Olivier , Godard Vincent , Lasserre Cécile , Wang Mingming , Braucher Régis , Talon Brigitte , de Sigoyer Julia , Xu Xiwei , Bourlès Didier L.
Published: January 2016

The dextral Longriba fault system (LFS), ~300 km long and constituting of two fault zones, has recently been recognized as an important structure of the eastern Tibetan plateau (Sichuan province), as it accommodates a significant amount of the deformation induced by the ongoing Indo‐Asian collision. Although previous paleoseismological investigations highlighted its high seismogenic potential, no systematic quantification of the dextral displacements along the fault system has been undertaken so far. As such information is essential to appraise fault behavior, we propose here a first detailed analysis of the segmentation of the Longriqu fault, the northern fault zone of the LFS, and an offset inventory of morphological features along the fault, using high‐resolutionPleiadessatellite images. We identify six major segments forming a mature fault zone. Offsets inventory suggests a characteristic coseismic displacement of ~4 m. Two alluvial fans, with minimum ages of 6.7 and 13.2 ka, respectively displaced by 23 ± 7 m and 40 ± 5 m, give an estimate of the maximal horizontal slip rate on the Longriqu fault of 3.2 ± 1.1 mm yr−1. As a result, a minimum ~1340 year time interval between earthquakes is expected.
Further study of circulating IgG antibodies to CD25‐derived peptide antigens in nonsmall cell lung cancer
Authors: Chen Cairen , Wang Weili , Meng Qingyong , Wu Ning , Wei Jun
Published: January 2016

A recent study reported that circulating antibodies to CD25‐derived peptide antigens were significantly higher in patients with nonsmall cell lung cancer (NSCLC) than control subjects. The present study was, thus, undertaken to replicate the initial finding with different sample sets. An in‐house ELISA was applied to determine circulating IgG antibodies to linear peptide antigens derived from CD25. A total of 111 patients with NSCLC and 216 control subjects were recruited and divided into the discovery sample (51 vs 108) and the validation sample (60 vs 108) based on the time of sampling. Student's t test showed that circulating anti‐CD25 IgG levels were significantly higher in the patient group than the control group (t = 2.23, P = 0.027) and the validation sample replicated this finding (t = 3.31, P = 0.0012), generating a combined P value of 0.0004 (χ2 = 20.8, df = 4). Fisher's combining probability revealed that patients with stage IV NSCLC had a significant increase in anti‐CD25 IgG levels compared with control subjects (χ2 = 22.1, df = 4, P = 0.0002) but those with the other three stages did not. This study suggests that circulating anti‐CD25 IgG antibodies may have prognostic rather than early diagnostic values for lung cancer.