bluuebunny/crossref_metadata_2025 huggingface dataset:
Field and modeling studies of aquifer heterogeneity to improve remediation planning in a multilayered aquifer system
Authors: Gigliuto Andrea , Righetti Chiara , Vaccari Roberta , Moretti Leandro
Published: June 2016

This paper presents the work carried out at a coastal contaminated site to define the presence and nature of heterogeneities in a complex hydrogeological aquifer system. The aim of the studies was to identify the effects of acquifer heterogeneities affecting plume migration in order to support remediation strategies. The hydrogeology of the area is characterized by the presence of a multilayer aquifer and a close relationship between groundwater and surface water (tidal fluctuations, lake system). Different approaches were utilized to investigate the system, including field and modeling studies. Field investigations included continuous groundwater level monitoring system, the monitoring of multi-level wells and the installation and sampling of new monitoring wells in order to define the vertical distribution of the chlorinated solvents (CAHs) contamination. The complexity of the hydrogeological system required hydraulic tests and tracers tests in order to verify the hydraulic interactions between aquifer layers and their relationship with surface water. The modeling studies have included the implementation of 3 separate numerical models of groundwater flow, aiming to verify the effectiveness of the previous site emergency remedial actions and to support remediation strategies in different project phases. The studies allowed to understand the downward plume migration of the CAHs: vertical hydraulic gradients induced by the surface water system and the complexity of the multilayered aquifer system due to presence of heterogeneities mainly affected the CAHs transport in the first acquifer.
La simulazione degli scambi acque superficiali/acque sotterranee: alcuni codici numerici a confronto
Authors: Borsi Iacopo , Rossetto Rudy
Published: June 2016

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Geochimica dell’idrosfera: come, quando e perché
Authors: Fidelibus M. Dolores
Published: June 2016

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Contro i lambicchi. Antonio Vallisneri e l’origine delle sorgenti
Authors: Luzzini Francesco
Published: June 2016

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From Fourier to Darcy, from Carslaw to Theis: the analogies between the subsurface behaviour of water and heat
Authors: Banks David
Published: June 2016

The analogy between the behaviour of groundwater in an aquifer and the conductive behaviour of heat in an aestifer is almost perfect. The development of groundwater flow theory has consistently drawn upon thermal analogues to find mathematical solutions: Darcy’s Law is analogous to Fourier’s. Charles Theis drew on Horatio Scott Carslaw’s heat conduction equations to develop his analysis of radial groundwater flow. Ogata and Banks refer to Carslaw and Jaeger’s work on heat diffusion to solve the longitudinal dispersion of solutes in flowing groundwater. The hydrogeologist is thus admirably equipped with the necessary conceptual models, mathematical tools and computer codes to become a practising thermogeologist
Methodological approach for evaluating the geo-exchange potential: VIGOR Project
Authors: Galgaro Antonio , Di Sipio Eloisa , Destro Elisa , Chiesa Sergio , Uricchio Vito , Bruno Delia , Masciale Rita , Lopez Nicola , Iaquinta Pasquale , Teza Giordano , Iovine Giulio , Montanari Domenico , Manzella Adele , Soleri Sergio , Greco Roberto , Di Bella Guido , Monteleone Salvatore , Sabatino Maria , Iorio Marina , Petruccione Emanuela , Giaretta Aurelio , Tranchida Giorgio , Trumpy Eugenio , Gola Gianluca , D'Arpa Stefania
Published: June 2016

In the framework of VIGOR Project, a national project coordinated by the Institute of Geosciences and Earth Resources (CNR-IGG) and sponsored by the Ministry of Economic Development (MiSE), dedicated to the evaluation of geothermal potential in the regions of the Convergence Objective in Italy (Puglia, Calabria, Campania and Sicily), is expected to evaluate the ability of the territory to heat exchange with the ground for air conditioning of buildings. To identify the conditions for the development of low enthalpy geothermal systems collected and organized on a regional scale geological and stratigraphic data useful for the preparation of a specific thematic mapping, able to represent in a synergistic and simplified way the physical parameters (geological, lithostratigraphic, hydrogeological, thermodynamic) that most influence the subsoil behavior for thermal exchange. The litho-stratigraphic and hydrogeological database created for every region led to the production of different cartographic thematic maps, such as the thermal conductivity (lithological and stratigraphical), the surface geothermal flux, the average annual temperature of air, the climate zoning, the areas of hydrogeological restrictions. To obtain a single representation of the geo-exchange potential of the region, the different thematic maps described must be combined together by means of an algorithm, defined on the basis of the SINTACS methodology. The purpose is to weigh the contributions of the involved parameters and to produce a preliminary synthesis map able to identify the territorial use of geothermal heat pump systems, based on the geological characteristics and in agreement with the existing regulatory constraints.
Modelling groundwater recharge in an alluvial aquifer of Somaliland with the groundwater flow model YAGmod
Authors: Cattaneo Laura , Vassena Chiara , Giudici Mauro , Petrucci Bruno
Published: June 2016

Since the 1970’s the Ged Deeble (GD) basin is exploited to supply water to the town of Hargeisa (Somaliland, East Africa, 350,000 inhabitants). The goal of this work is to improve the comprehension of the recharge mechanisms, by the simulation of groundwater flow, in order to assess the sustainability of present-day and future exploitation schemes that aim to satisfy the water demand of the city. For this goal, the exploration activities performed in the past were used to reconstruct the geological framework, the basin shape and the mechanisms of recharge and to define the conceptual model. The mathematical model YAGMod, that simulates groundwater steady flow in presence of head-dependent sources and boundary conditions, was applied to quantify the terms of the groundwater balance. Different management scenarios, accompanied by a sensitivity analysis, have been examined to verify if the future water demand of the city could be satisfied and to provide some indications about the land use planning and the management of water resources.
Corto circuito termico nei sistemi di geoscambio a circuito aperto
Authors: Cultrera Matteo
Published: June 2016

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I sistemi informativi di supporto alle decisioni (DSS) nell’attivita’ di pianificazione e valutazione ambientale degli impianti geotermici a bassa entalpia: attualita’ e prospettive di sviluppo
Authors: Bersano Begey Marco
Published: June 2016

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Il Signor Cestoni alla prova delle pignatte
Authors: Luzzini Francesco
Published: June 2016

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The groundwater intrinsic vulnerability map of S. Eufemia Lamezia Plain (Calabria)
Authors: Cuiuli Enzo
Published: June 2016

The study area is the plain of S. Eufemia Lamezia (Calabria) located in correspondence of the homonymous gulf, along the Tyrrhenian coast. The method used for the construction of the vulnerability map of the superficial acquifer of S. Eufemia Lamezia plain is the SINTACS. This method provides an estimate of vulnerability through the calculation of the Vulnerability Index, for each cell, with which it has been discretized the zone of study. The territory has been divided into areas characterized by vulnerability degree from medium to very high, passing through the intermediate terms. In the southern sector of the plain, where the depth of groundwater is variable, between 4,00 m and 0,50 m from the ground level, are located: the industrial/ handcrafted area of Lamezia Terme, the areas with the greatest agricultural and zootechnical yields, tourist facilities and private houses along the coast. They represent a potential pollution risk for the superficial aquifer. In the northern sector, where the depth of groundwater is variable between 38,00 m from ground level (inland areas) to 1,00 m from ground level (along the coast), the practiced agricultural activities, are different from those of the southern sector of the plain (olive trees, citrus groves, arable land, etc.), but here there are too tourist facilities and private houses along the coast. These various activities contribute, even in this area to outline a potential risk of pollution to the superficial aquifer of S. Eufemia Lamezia plain which, however, is slightly less worrying than in the south sector.
Il metodo AEM, un nuovo strumento per l'idrogeologia
Authors: Menghini Antonio , Viezzoli Andrea
Published: June 2016

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"Acque calde" ai congressi di Mórahalom (Ungheria) e a Idrovulc2013
Authors: Ducci Daniela , Petitta Marco
Published: June 2016

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Problemi di corrosione e incrostazione della colonna pozzo
Authors: Cempini Nicola
Published: June 2016

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Acque sotterranee in primo piano nell’agenda europea
Authors: Petitta Marco
Published: June 2016

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Proposta di metodo semiquantitavo per la valutazione dell’efficacia della manutenzione di un pozzo
Authors: Cempini Nicola
Published: June 2016

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Il paradosso di Kircher (che paradosso non è)
Authors: Luzzini Francesco
Published: June 2016

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L’iter normativo della definizione delle aree critiche e d’attenzione nel Lazio
Authors: Bianchini Antonio
Published: June 2016

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Il 40esimo Congresso Internazionale dell’IAH a Perth
Authors: Petitta Marco , Ducci Daniela , Re Viviana
Published: June 2016

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La modellazione numerica dei contesti vulcanici
Authors: Taviani Sara
Published: June 2016

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Archi in numero d’intorno a mille. L’Acquedotto Mediceo di Asciano
Authors: Luzzini Francesco
Published: June 2016

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Un dibattito lungo secoli. La galleria Adige-Garda
Authors: Luzzini Francesco
Published: June 2016

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Verso una gestione più efficiente delle acque meteoriche nelle città del Mediterraneo
Authors: Escuder-Bueno Ignacio , Andrés-Doménech Ignacio , Perales-Momparler Sara , Morales-Torres Adrián , Rossetto Rudy , Bonari E. , Ciabatti Sandro , Redini Marco
Published: June 2016

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Flowpath 2014 – National Meeting on Hydrogeology, Viterbo, 18-19 giugno 2014
Authors: Piscopo Vincenzo , Baiocchi Antonella , Lotti Francesca
Published: June 2016

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L’autarchia delle acque. Mario Bettini e il moto perpetuo
Authors: Luzzini Francesco
Published: June 2016

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Progetto life aquor: verso una strategia di riequilibrio quantitativo delle acque sotterranee dell’alta pianura vicentina attraverso la ricarica delle falde e il risparmio idrico
Authors: Gusmaroli G. , Muraro T.
Published: June 2016

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I mirabili discorsi di Monsieur Palissy
Authors: Luzzini Francesco
Published: June 2016

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Sfruttamento idropotabile e geotermico: una convivenza possibile?
Authors: Cempini Nicola
Published: June 2016

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I fanghi prodigiosi. Gli studi naturalistici sulle salse emiliane
Authors: Luzzini Francesco
Published: June 2016

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Il passato è la chiave del presente: Vittorio Novarese e l’eruzione di gas a Fiumicino del 1925
Authors: Argentieri Alessio , Pantaloni Marco
Published: June 2016

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Physico-chemical model as a tool to explain the composition of thermal waters in tectonically active regions
Authors: Kuz’mina Elena A. , Veshcheva Svetlana V. , Zarubina Olga V.
Published: June 2016

In the present work, we address the structural-hydrogeological conditions for the Baikal Rift System (BRS) natural water formation in terms of lithospheric plate tectonics. A comparative analysis for the trace-element composition of thermal waters of rift and island-arc systems was made. We analyzed the thermal water trace elements to better understand the water origin through physico-chemical modeling. The results of different simulations of thermodynamic modeling are herein presented, in order to investigate the formation processes of thermal waters according to the geodynamic activity in the BRS region. Modeling results for the Alginsky Thermal Spring in BRS showed that all the elements can be accumulated in the waters from granites except for U, Li, Rb, B, Mo, Sr, S. These elements may have endogenous nature.
Dall’AIGA ad AQUA (con la collaborazione di ANIPA)
Authors: Petitta Marco , Ducci Daniela
Published: June 2016

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Methodological approach for a sustainable management of water inflow and geothermal energy in tunnels
Authors: Furno Fabio , Barla Marco , Dematteis Antonio , Lo Russo Stefano
Published: June 2016

It is quite unusual to consider the exploitation of geothermal resources during at the tunnel design stage. This paper is intended to analyse the nature and the potential of the geothermal resources. These are essentially the hot or cold water inflow and the temperature of the surrounding ground itself. A methodological approach is proposed to face the problem, determine relevant information and estimate the attractiveness of the application. The approach is then applied to the case study of the metro line Dudullu-Bostanci in Istanbul, currently under design, by identifying a possible application of heat exchangers integrated into the tunnel lining and evaluating preliminarily the environmental and economical aspects.
Remarks on the hydrogeological setting of S. Eufemia Lamezia plain through the development of the top surface of the intermediate confined aquifer (central Calabria)
Authors: Cuiuli Enzo
Published: June 2016

The S. Eufemia Lamezia plain, located in central Calabria, is characterized by the presence of a multi-layered aquifer. In particular, it was studied the intermediate artesian aquifer, content in the Pliocene sands and sandstones. The collection of new lithostratigraphic data, related to drilling for water supplies, allowed to draw the map of the top of intermediate artesian aquifer underlying in the study area. The top surface of sands and sandstones map, presented here, seems to confirm the structural-geological data of the surface showing, also in depth, the conditioning of tectonics on the study area and on the groundwater flow. The analysis of the selected stratigraphic data shows that the studied aquifer is constituted by Pliocene deposits of sand and sandstones, confined to the top by Pliocene clay. Therefore locally hydraulic connections with the shallow aquifer for leackage phenomena are possible. The supply of the studied aquifer happens mainly for lateral recharge because the clay horizon that borders with the top of the aquifer prevents direct transfer of rainfall recharge. However, a reduced recharge rate is due to the meteoric recharge, which is possible in limited parts of the territory to the east of the study area and over. Therefore, this study aims to implement the knowledge of the groundwater flow of S. Eufemia plain by returning the top intermediate confined aquifer map which, is little studied but strongly exploited because, respect to the shallow aquifer, is more productive and more protected by potential contamination due to the presence of the aquiclude/aquitard which isolates it by the top.
L’APD. Lgs. n.152/2006 - La messa in sicurezza di siti contaminati: la difficoltà di applicazione di efficaci barriere idrauliche in Italia
Authors: Bonfà Isidoro
Published: June 2016

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Ugo Ventriglia, pioniere dell'idrogeologia delle aree urbane nel laboratorio naturale di Roma.
Authors: Argentieri Alessio
Published: June 2016

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Retention in care outcomes for HIV pre‐exposure prophylaxis implementation programmes among men who have sex with men in three US cities
Authors: Chan Philip A , Mena Leandro , Patel Rupa , Oldenburg Catherine E , Beauchamps Laura , Perez‐Brumer Amaya G , Parker Sharon , Mayer Kenneth H , Mimiaga Matthew J , Nunn Amy
Published: June 2016

Introduction

Despite the efficacy of pre‐exposure prophylaxis (PrEP) in preventing HIV transmission, few studies have evaluated PrEP use and retention in care outcomes in real‐world settings outside of clinical trials.

Methods

Data were collected from PrEP clinical care programmes in three mid‐size US cities: Providence, Rhode Island (RI); Jackson, Mississippi (MS); and St. Louis, Missouri (MO). We assessed the demographic and social characteristics of patients prescribed PrEP and documented their insurance and copayment experiences. We assessed retention in PrEP care at three and six months. Multivariate analyses were used to predict retention in care among men who have sex with men (MSM). HIV acquisition among the cohort was also assessed.

Results

A total of 267 (RI: 117; MS: 88; MO: 62) patients were prescribed PrEP; 81% filled prescriptions (RI: 73%; MS: 82%; MO: 94%; p<0.001). Patients in MS and MO were more commonly African American than in RI (72% and 26% vs. 7%, respectively), but less frequently Latino (2% and 3% vs. 24%, respectively). More patients reported living below the federal poverty line in MS (52%) compared to MO (23%) and RI (26%). Most patients were MSM (RI: 92%; MS: 88%; MO: 84%). The majority of MSM reported recent condomless anal sex (RI: 70%; MS: 65%; MO: 75%). Among 171 patients prescribed PrEP at least six months beforehand, 72% were retained in care at three months (RI: 68%; MS: 70%; MO: 87%; p=0.12) and 57% were retained in PrEP care at six months (RI: 53%: MS: 61%; MO: 63%; p=0.51). Insurance status and medication costs were not found to be significant barriers for obtaining PrEP. Three patients became infected with HIV during the six‐month period after being prescribed PrEP (1.1%; 3/267), including one in RI (suspected acute HIV infection), one in MO (confirmed poor adherence) and one in MS (seroconverted just prior to initiation).

Conclusions

PrEP initiation and retention in care differed across these distinct settings. In contrast, retention in PrEP care was consistently suboptimal across sites. Further research is needed to identify the individual, social and structural factors that may impede or enhance retention in PrEP care
Study on the application of shear-wave elastography to thin-layered media and tubular structure: Finite-element analysis and experiment verification
Authors: Jang Jun-keun , Kondo Kengo , Namita Takeshi , Yamakawa Makoto , Shiina Tsuyoshi
Published: June 2016

Shear-wave elastography (SWE) enables the noninvasive and quantitative evaluation of the mechanical properties of human soft tissue. Generally, shear-wave velocity (C
S) can be estimated using the time-of-flight (TOF) method. Young’s modulus is then calculated directly from the estimated C
S. However, because shear waves in thin-layered media propagate as guided waves, C
S cannot be accurately estimated using the conventional TOF method. Leaky Lamb dispersion analysis (LLDA) has recently been proposed to overcome this problem. In this study, we performed both experimental and finite-element (FE) analyses to evaluate the advantages of LLDA over TOF. In FE analysis, we investigated why the conventional TOF is ineffective for thin-layered media. In phantom experiments, C
S results estimated using the two methods were compared for 1.5 and 2% agar plates and tube phantoms. Furthermore, it was shown that Lamb waves can be applied to tubular structures by extracting lateral waves traveling in the long axis direction of the tube using a two-dimensional window. Also, the effects of the inner radius and stiffness (or shear wavelength) of the tube on the estimation performance of LLDA were experimentally discussed. In phantom experiments, the results indicated good agreement between LLDA (plate phantoms of 2 mm thickness: 5.0 m/s for 1.5% agar and 7.2 m/s for 2% agar; tube phantoms with 2 mm thickness and 2 mm inner radius: 5.1 m/s for 1.5% agar and 7.0 m/s for 2% agar; tube phantoms with 2 mm thickness and 4 mm inner radius: 5.3 m/s for 1.5% agar and 7.3 m/s for 2% agar) and SWE measurements (bulk phantoms: 5.3 m/s ± 0.27 for 1.5% agar and 7.3 m/s ± 0.54 for 2% agar).
A unique mating strategy without physical contact during fertilization in Bombay Night Frogs (Nyctibatrachus humayuni) with the description of a new form of amplexus and female call
Authors: Willaert Bert , Suyesh Robin , Garg Sonali , Giri Varad B. , Bee Mark A. , Biju S.D.
Published: June 2016

Anurans show the highest diversity in reproductive modes of all vertebrate taxa, with a variety of associated breeding behaviours. One striking feature of anuran reproduction is amplexus. During this process, in which the male clasps the female, both individuals’ cloacae are juxtaposed to ensure successful external fertilization. Several types of amplexus have evolved with the diversification of anurans, and secondary loss of amplexus has been reported in a few distantly related taxa. WithinNyctibatrachus, a genus endemic to the Western Ghats of India, normal axillary amplexus, a complete loss of amplexus, and intermediate forms of amplexus have all been suggested to occur, but many species remain unstudied. Here, we describe the reproductive behaviour ofN. humayuni, including a new type of amplexus. The dorsal straddle, here defined as a loose form of contact in which the male sits on the dorsum of the female prior to oviposition but without clasping her, is previously unreported for anurans. When compared to known amplexus types, it most closely resembles the form of amplexus observed in Mantellinae. Furthermore, we prove that, opposed to the situation in most anurans, male semen release happens before egg deposition. We hypothesize that the male ejaculates on the female’s dorsum and that sperm subsequently runs from her back and hind legs before fertilizing the eggs. A second feature characterizing anuran breeding is the advertisement call, mostly produced solely by males. Despite recent descriptions of several newNyctibatrachusspecies, few studies have explored their vocal repertoire. We describe both the male advertisement call and a female call forN. humayuni. The presence of a female call has not been reported within Nyctibatrachidae, and has been reported in less than 0.5% of anuran species. Altogether, our results highlight a striking diversity and several unique aspects ofNyctibatrachusbreeding behaviour.
Transient turbid water mass reduces temperature-induced coral bleaching and mortality in Barbados
Authors: Oxenford Hazel A. , Vallès Henri
Published: June 2016

Global warming is seen as one of the greatest threats to the world's coral reefs, and with the continued rise in sea surface temperature predicted into the future, there is a great need for further understanding of how to prevent and address the damaging impacts. This is particularly so for countries whose economies depend heavily on healthy reefs, such as those of the eastern Caribbean. Here, we compare the severity of bleaching and mortality for five dominant coral species at six representative reef sites in Barbados during the two most significant warm-water events ever recorded in the eastern Caribbean, i.e., 2005 and 2010, and describe prevailing island-scale sea water conditions during both events. In so doing, we demonstrate that coral bleaching and subsequent mortality were considerably lower in 2010 than in 2005 for all species, irrespective of site, even though the anomalously warm water temperature profiles were very similar between years. We also show that during the 2010 event, Barbados was engulfed by a transient dark green turbid water mass of riverine origin coming from South America. We suggest that reduced exposure to high solar radiation associated with this transient water mass was the primary contributing factor to the lower bleaching and mortality observed in all corals. We conclude that monitoring these episodic mesoscale oceanographic features might improve risk assessments of southeastern Caribbean reefs to warm-water events in the future.
Phosphorus mobilizing consortium Mammoth P™enhances plant growth
Authors: Baas Peter , Bell Colin , Mancini Lauren M. , Lee Melanie N. , Conant Richard T. , Wallenstein Matthew D.
Published: June 2016

Phosphorus (P) is a critical nutrient used to maximize plant growth and yield. Current agriculture management practices commonly experience low plant P use efficiency due to natural chemical sorption and transformations when P fertilizer is applied to soils. A perplexing challenge facing agriculture production is finding sustainable solutions to deliver P more efficiently to plants. Using prescribed applications of specific soil microbial assemblages to mobilize soil bound—P to improve crop nutrient uptake and productivity has rarely been employed. We investigated whether inoculation of soils with a bacterial consortium developed to mobilize soil P, named Mammoth PTM, could increase plant productivity. In turf, herbs, and fruits, the combination of conventional inorganic fertilizer combined with Mammoth PTMincreased productivity up to twofold compared to the fertilizer treatments without the Mammoth PTMinoculant. Jalapeño plants were found to bloom more rapidly when treated with either Mammoth P. In wheat trials, we found that Mammoth PTMby itself was able to deliver yields equivalent to those achieved with conventional inorganic fertilizer applications and improved productivity more than another biostimulant product. Results from this study indicate the substantial potential of Mammoth PTMto enhance plant growth and crop productivity.
Admission Test as Predictor of Performance of Students in the English Subject
Authors: Ocbian Magdalena M. , Gamba Michael P. , Ricafort Jhonner D.
Published: June 2016

Admission testing is an integral part of higher education institutions (HEIs) in maintaining the quality educational standards. Through testing, the HEI's can objectively select applicants that are likely to succeed in their intended course. The study was conducted to determine the predictive validity of the admission Tests of the secondary and college levels to their performance in English subjects using the descriptive-correlational designs. The respondents were the secondary students of the SSC Laboratory High School and First-Year college students from school years 2009-2012. The Pearson Correlation was used to determine the relationship of the admission test results and the performance of the identified respondents on the English subject. The GPA on English and SSC Admission test results on college level shows a moderate positive relationship. Also, high school level denotes a strong positive relationship. This relationship had been manifested in 40% of the respondents in secondary level, and 13% of the respondents in college level. This significant relationship suggests that admission test determines the potential performance of the students in their English subject in both secondary and tertiary level. Thus, it was concluded that SSC Admission Test is a valid predictor of the students' performance in English subject.
LA FIGURA JURÍDICA DE LA ENSEÑANZA RELIGIOSA ESCOLAR
Authors:   Universidad Católica de Salta (Argentina), Méndez Julio Raúl
Published: June 2016

El trabajo propone una visión articulada de las normas, especialmente de derecho convencional, que resultan aplicables a la Enseñanza Religiosa Escolar (ERE). De ellas extrae siete principios jurídicos, que conforman la figura de dicho instituto. Si bien la ERE es una realidad vigente en la mayor parte de los países miembros de la UNESCO, sin embargo, es objeto de una fuerte oposición política. Ésta suele proyectarse en planteos legales que postulan su supresión. El autor señala que una adecuada aplicación de la figura delineada responde al ejercicio de los derechos fundamentales, y sería razonablemente suficiente para oponer a esos planteos adversos.
Uncertainties in the attribution of greenhouse gas warming and implications for climate prediction
Authors: Jones Gareth S. , Stott Peter A. , Mitchell John F. B.
Published: June 2016

Using optimal detection techniques with climate model simulations, most of the observed increase of near‐surface temperatures over the second half of the twentieth century is attributed to anthropogenic influences. However, the partitioning of the anthropogenic influence to individual factors, such as greenhouse gases and aerosols, is much less robust. Differences in how forcing factors are applied, in their radiative influence and in models' climate sensitivities, substantially influence the response patterns. We find that standard optimal detection methodologies cannot fully reconcile this response diversity. By selecting a set of experiments to enable the diagnosing of greenhouse gases and the combined influence of other anthropogenic and natural factors, we find robust detections of well‐mixed greenhouse gases across a large ensemble of models. Of the observed warming over the twentieth century of 0.65 K/century we find, using a multimodel mean not incorporating pattern uncertainty, a well‐mixed greenhouse gas warming of 0.87 to 1.22 K/century. This is partially offset by cooling from other anthropogenic and natural influences of −0.54 to −0.22 K/century. Although better constrained than recent studies, the attributable trends across climate models are still wide, with implications for observational constrained estimates of transient climate response. Some of the uncertainties could be reduced in future by having more model data to better quantify the simulated estimates of the signals and natural variability, by designing model experiments more effectively and better quantification of the climate model radiative influences. Most importantly, how model pattern uncertainties are incorporated into the optimal detection methodology should be improved.
Changes in precipitating snow chemistry with location and elevation in the California Sierra Nevada
Authors: Creamean Jessie M. , Axson Jessica L. , Bondy Amy L. , Craig Rebecca L. , May Nathaniel W. , Shen Hongru , Weber Michael H. , Pratt Kerri A. , Ault Andrew P.
Published: June 2016

Orographic snowfall in the Sierra Nevada Mountains is an important source of water for California and can vary significantly on an annual basis. The microphysical properties of orographic clouds and subsequent formation of precipitation are impacted, in part, by aerosols of varying size, number, and chemical composition, which are incorporated into clouds formed along the Sierra barrier. Herein, the physicochemical properties and sources of insoluble residues and soluble ions found in precipitation samples were explored for three sites of variable elevation in the Sierra Nevada during the 2012–2013 winter season. Residues were characterized using a suite of physicochemical techniques to determine the size‐resolved number concentrations and associated chemical composition. A transition in the aerosol sources that served as cloud seeds or were scavenged in‐cloud and below‐cloud was observed as a function of location and elevation. Anthropogenic influence from the Central Valley was dominant at the two lowest elevation sites (1900 and 2200 m above mean sea level (AMSL)), whereas long‐range transported mineral dust was a larger contributor at the highest elevation site where cleaner conditions were observed (2600 m AMSL). The residues and soluble ions observed provide insight into how multiple aerosol sources can impact cloud and precipitation formation processes, even over relatively small spatial scales. The transition with increasing elevation to aerosols that serve as ice nucleating particles may impact the properties and extent of snowfall in remote mountain regions where snowpack provides a vital supply of water.
Validating a mass balance accounting approach to using 7Be measurements to estimate event‐based erosion rates over an extended period at the catchment scale
Authors: Porto Paolo , Walling Des E. , Cogliandro Vanessa , Callegari Giovanni
Published: June 2016

Use of the fallout radionuclides cesium‐137 and excess lead‐210 offers important advantages over traditional methods of quantifying erosion and soil redistribution rates. However, both radionuclides provide information on longer‐term (i.e., 50–100 years) average rates of soil redistribution. Beryllium‐7, with its half‐life of 53 days, can provide a basis for documenting short‐term soil redistribution and it has been successfully employed in several studies. However, the approach commonly used introduces several important constraints related to the timing and duration of the study period. A new approach proposed by the authors that overcomes these constraints has been successfully validated using an erosion plot experiment undertaken in southern Italy. Here, a further validation exercise undertaken in a small (1.38 ha) catchment is reported. The catchment was instrumented to measure event sediment yields and beryllium‐7 measurements were employed to document the net soil loss for a series of 13 events that occurred between November 2013 and June 2015. In the absence of significant sediment storage within the catchment's ephemeral channel system and of a significant contribution from channel erosion to the measured sediment yield, the estimates of net soil loss for the individual events could be directly compared with the measured sediment yields to validate the former. The close agreement of the two sets of values is seen as successfully validating the use of beryllium‐7 measurements and the new approach to obtain estimates of net soil loss for a sequence of individual events occurring over an extended period at the scale of a small catchment.
Revisiting extreme storms of the past 100 years for future safety of large water management infrastructures
Authors: Chen Xiaodong , Hossain Faisal
Published: June 2016

Historical extreme storm events are widely used to make Probable Maximum Precipitation (PMP) estimates, which form the cornerstone of large water management infrastructure safety. Past studies suggest that extreme precipitation processes can be sensitive to land surface feedback and the planetary warming trend, which makes the future safety of large infrastructures questionable given the projected changes in land cover and temperature in the coming decades. In this study, a numerical modeling framework was employed to reconstruct 10 extreme storms over CONUS that occurred during the past 100 years, which are used by the engineering profession for PMP estimation for large infrastructures such as dams. Results show that the correlation in daily rainfall for such reconstruction can range between 0.4 and 0.7, while the correlation for maximum 3‐day accumulation (a standard period used in infrastructure design) is always above 0.5 for post‐1948 storms. This suggests that current numerical modeling and reanalysis data allow us to reconstruct big storms after 1948 with acceptable accuracy. For storms prior to 1948, however, reconstruction of storms shows inconsistency with observations. Our study indicates that numerical modeling and data may not have advanced to a sufficient level to understand how such old storms (pre‐1948) may behave in future warming and land cover conditions. However, the infrastructure community can certainly rely on the use of model reconstructed extreme storms of the 1948‐present period to reassess safety of our large water infrastructures under assumed changes in temperature and land cover.
S−to−P heterogeneity ratio in the lower mantle and thermo‐chemical implications
Authors: Tesoniero Andrea , Cammarano Fabio , Boschi Lapo
Published: June 2016

We evaluate the thermo‐chemical state of the lower mantle by analysing the differences in the pattern of heterogeneity between shear and compressional velocity variations and the
heterogeneity ratio (
) as mapped in our model SPani and in alternative joint models. Robust structural differences between VP and VS evidence the presence of compositional heterogeneity within the two Large Low Shear Velocity Provinces (LLSVPs). We find also an increasing decorrelation with depth that can be associated with compositional layering of the LLSVPs. In addition, our model shows heterogeneity in the transition zone and mid mantle by complex morphology of subducting slabs and further differences between VP and VS that point to an unexpected heterogeneous lower mantle. Precise estimates of compositional heterogeneities are not yet affordable because of the difficulty to provide quantitative measure of
, making it difficult to use this ratio to evaluate chemical heterogeneity. For instance,
global median value (
) drops from
to
, at 2500 km depth when the VP component of SPani is replaced by a VP model resulting from a differently regularized inversion and obtaining an equally good data fit. An increase of 20% of the SPani VP anomalies also drastically reduces
without significantly degrading the data fit. Noise in model parameters also leads to overestimate
in the two LLSVPs as we show with synthetic tests. Additional mineral physics uncertainties for compositional effects on
and for the conversion of
and
into density further complicates a precise chemical interpretation.
Meteoritic influence on sodium and potassium abundance in the lunar exosphere measured by LADEE
Authors: Szalay Jamey R. , Horányi Mihály , Colaprete Anthony , Sarantos Menelaos
Published: June 2016

The Lunar Atmosphere and Dust Environment Explorer (LADEE) orbited the Moon for approximately 6 months, taking data with the Lunar Dust Experiment (LDEX), Ultraviolet‐Visible Spectrometer (UVS), and Neutral Mass Spectrometer (NMS). Here we compare coincident LDEX measurements of meteoritic influx to exospheric column densities of Na and K derived by UVS. We report a strong correlation of exospheric potassium and meteoroid ejecta during the Geminids meteoroid shower, exhibiting a much stronger response than sodium. With the exception of the Geminids, we find a weak correlation between the sporadic meteoroid influx as measured by LDEX and exospheric density as measured by UVS.
Modeling 3‐D crustal velocities in the United States and Canada
Authors: Snay Richard A. , Freymueller Jeffrey T. , Craymer Michael R. , Pearson Chris F. , Saleh Jarir
Published: June 2016

A numerical model for three‐dimensional (3‐D) crustal velocities has been derived for most of the United States and Canada, primarily from repeated geodetic data. This model provides a foundation for a prototype of the TRANS4D software. TRANS4D is being developed to enable geospatial professionals and others to transform 3‐D positional coordinates across time. The derived model reveals several macroscopic features of the 3‐D velocity field, including the pervasive presence of the glacial isostatic adjustment associated with the past melting of the ice fields that formed more than 19,000 years ago during the Last Glacial Maximum. In this study, the present‐day 3‐D velocity field associated with this melting (as estimated via the recently published ICE‐6G_C (VM5a) model) was subtracted from this study's total 3‐D velocity field to identify features of the residual velocity field. In particular, this study introduces the NA_ICE‐6G reference frame in which residual horizontal velocities have magnitudes that are less than 2 mm/yr everywhere east of longitude 104°W and south of latitude 60°N, except in southern Texas. Residual horizontal velocities of greater magnitude are found west and/or north of these two boundaries, and they are due mostly to interactions among tectonic plates with localized pockets due to other geophysical phenomena. Large residual vertical velocities, some with values exceeding 30 mm/yr, are found in southeastern Alaska. The uplift occurring here is due to present‐day melting of glaciers and ice fields formed during the Little Ice Age glacial advance that occurred between 1550 A.D. and 1850 A.D.
Interannual variability of winter‐spring temperature in the Middle Atlantic Bight: Relative contributions of atmospheric and oceanic processes
Authors: Chen Ke , Kwon Young‐Oh , Gawarkiewicz Glen
Published: June 2016

Relative contributions between the local atmospheric and oceanic processes on the interannual variability of winter‐spring shelf temperature in the Middle Atlantic Bight (MAB) are investigated based on a regional ocean model. The model demonstrates sufficient capability to realistically simulate the interannual temperature changes during 2003–2014. On interannual time scales, the mean winter/spring temperature in the MAB is determined by the combination of the initial temperature at the beginning of the season and the mean cumulative air‐sea flux, while the mean cumulative ocean advective flux plays a secondary role. In spite of the overall importance of air‐sea flux in determining the winter and spring temperature, the relative contributions between air‐sea flux and ocean advective flux on the evolution of the temperature anomaly in each individual year varies. The predictability of spring (April–June) temperature based on winter (January–March) temperature is weak because the temporal decorrelation time scale changes significantly from year to year. Both the highly variable shelf temperature and its decorrelation time scale are affected by the changes in the relative contributions between the air‐sea flux and ocean advective flux.
Impact of current speed on mass flux to a model flexible seagrass blade
Authors: Lei Jiarui , Nepf Heidi
Published: June 2016

Seagrass and other freshwater macrophytes can acquire nutrients from surrounding water through their blades. This flux may depend on the current speed (U), which can influence both the posture of flexible blades (reconfiguration) and the thickness of the flux‐limiting diffusive layer. The impact of current speed (U) on mass flux to flexible blades of model seagrass was studied through a combination of laboratory flume experiments, numerical modeling and theory. Model seagrass blades were constructed from low‐density polyethylene (LDPE), and 1, 2‐dichlorobenzene was used as a tracer chemical. The tracer mass accumulation in the blades was measured at different unidirectional current speeds. A numerical model was used to estimate the transfer velocity (K) by fitting the measured mass uptake to a one‐dimensional diffusion model. The measured transfer velocity was compared to predictions based on laminar and turbulent boundary layers developing over a flat plate parallel to flow, for whichand, respectively. The degree of blade reconfiguration depended on the dimensionless Cauchy number,Ca, which is a function of both the blade stiffness and flow velocity. For largeCa, the majority of the blade was parallel to the flow, and the measured transfer velocity agreed with laminar boundary layer theory,. For smallCa, the model blades remained upright, and the flux to the blade was diminished relative to the flat‐plate model. A meadow‐scale analysis suggests that the mass exchange at the blade scale may control the uptake at the meadow scale.
Basal melt, seasonal water mass transformation, ocean current variability, and deep convection processes along the Amery Ice Shelf calving front, East Antarctica
Authors: Herraiz‐Borreguero L. , Church J. A. , Allison I. , Peña‐Molino B. , Coleman R. , Tomczak M. , Craven M.
Published: June 2016

Despite the Amery Ice Shelf (AIS) being the third largest ice shelf in Antarctica, the seasonal variability of the physical processes involved in the AIS‐ocean interaction remains undocumented and a robust observational, oceanographic‐based basal melt rate estimate has been lacking. Here we use year‐long time series of water column temperature, salinity, and horizontal velocities measured along the ice shelf front from 2001 to 2002. Our results show strong zonal variations in the distribution of water masses along the ice shelf front: modified Circumpolar Deep Water (mCDW) arrives in the east, while in the west, Ice Shelf Water (ISW) and Dense Shelf Water (DSW) formed in the Mackenzie polynya dominate the water column. Baroclinic eddies, formed during winter deep convection (down to 1100 m), drive the inflow of DSW into the ice shelf cavity. Our net basal melt rate estimate is 57.4 ± 25.3 Gt yr−1 (1 ± 0.4 m yr−1), larger than previous modeling‐based and glaciological‐based estimates, and results from the inflow of DSW (0.52 ± 0.38 Sv; 1 Sv = 106 m3 s−1) and mCDW (0.22 ± 0.06 Sv) into the cavity. Our results highlight the role of the Mackenzie polynya in the seasonal exchange of water masses across the ice shelf front, and the role of the ISW in controlling the formation rate and thermohaline properties of DSW. These two processes directly impact on the ice shelf mass balance, and on the contribution of DSW/ISW to the formation of Antarctic Bottom Water.
Solid‐State Reactions of SiC/W–25Re Alloy and Thermal Stability of SiC/Ti/W–25Re Alloy under High‐Temperature Annealing
Authors: Han Jun Sae , Jang Seung Sik , Park Dong Yong , Oh Yong Jun , Park Seong Jin
Published: June 2016

Solid‐state reactions of SiC/W–25Re alloy and SiC/Ti/W–25Re alloy are investigated under the high‐temperature annealing at1 500 °C. The interface reaction layer between SiC and W–25Re alloy is composed of WC– WSi2– W5Si3– W–Re sigma phase – dendrite microstructure. Solid‐state reactions between W and SiC form two types of W‐silicides and the relative depletion of W brings formation of the W–Re sigma phase. In order to prevent direct interfacial reactions, Ti layer is intercalated as a secondary buffer layer. Compared to the original interface, thicknesses of both reaction layer and dendrite layer are significantly decreased. Although the thermal reaction of Ti and W brings inhomogeneous characteristics, the proposed functionally graded structure is expected to enhance the thermal stability.
Multi‐Material Tissue Engineering Scaffold with Hierarchical Pore Architecture
Authors: Morgan Kathy Ye , Sklaviadis Demetra , Tochka Zachary L. , Fischer Kristin M. , Hearon Keith , Morgan Thomas D. , Langer Robert , Freed Lisa E.
Published: June 2016

Multi‐material polymer scaffolds with multiscale pore architectures are characterized and tested with vascular and heart cells as part of a platform for replacing damaged heart muscle. Vascular and muscle scaffolds are constructed from a new material, poly(limonene thioether) (PLT32i), which meets the design criteria of slow biodegradability, elastomeric mechanical properties, and facile processing. The vascular–parenchymal interface is a poly(glycerol sebacate) (PGS) porous membrane that meets different criteria of rapid biodegradability, high oxygen permeance, and high porosity. A hierarchical architecture of primary (macroscale) and secondary (microscale) pores is created by casting the PLT32i prepolymer onto sintered spheres of poly(methyl methacrylate) (PMMA) within precisely patterned molds followed by photocuring, de‐molding, and leaching out the PMMA. Prefabricated polymer templates are cellularized, assembled, and perfused in order to engineer spatially organized, contractile heart tissue. Structural and functional analyses show that the primary pores guide heart cell alignment and enable robust perfusion while the secondary pores increase heart cell retention and reduce polymer volume fraction.