bluuebunny/crossref_metadata_2025 huggingface dataset:
Cosmic Rays in Intermittent Magnetic Fields
Authors: Shukurov Anvar , Snodin Andrew P. , Seta Amit , Bushby Paul J. , Wood Toby S.
Published: April 2017

The propagation of cosmic rays in turbulent magnetic fields is a diffusive process driven by the scattering of the charged particles by random magnetic fluctuations. Such fields are usually highly intermittent, consisting of intense magnetic filaments and ribbons surrounded by weaker, unstructured fluctuations. Studies of cosmic-ray propagation have largely overlooked intermittency, instead adopting Gaussian random magnetic fields. Using test particle simulations, we calculate cosmic-ray diffusivity in intermittent, dynamo-generated magnetic fields. The results are compared with those obtained from non-intermittent magnetic fields having identical power spectra. The presence of magnetic intermittency significantly enhances cosmic-ray diffusion over a wide range of particle energies. We demonstrate that the results can be interpreted in terms of a correlated random walk.
Voiding Urosonography with Second-Generation Ultrasound Contrast Agent for Diagnosis of Vesicoureteric Reflux: First Local Pilot Study
Authors: Kuzmanovska Dafina , Risteski Aleksandar , Kambovska Margarita , Trpcevski Tase , Sahpazova Emilija , Petrovski Mile
Published: April 2017

BACKGROUND: Vesicoureteric reflux (VUR) is an important association of paediatric urinary tract infection (UTI) found in 30-50% of all children presenting with first UTI. Contrast-enhanced voiding ultrasonography (ceVUS) has become an important radiation-free method for VUR detection in children. Its sensitivity in detecting VUR has greatly improved due to the development of the contrast-specific ultrasound techniques and the introduction of the second-generation ultrasound contrast agent, superseding the diagnostic accuracy of standard radiological procedures.AIM: This article aimed to summarise the current literature and discuss the first local pilot study performed in our institution on detection of vesicoureteric reflux by contrast-enhanced voiding ultrasonography with second- generation agent (SonoVue, Bracco, Italy).MATERIAL AND METHODS: Retrospective review of the first 31 ceVUS (24 girls, 7 boys) was presented.Â  Age range was 2 months to 18 years (mean = 6.4 Â± 4.9).RESULTS:Â  All examinations were well tolerated without any adverse incident. VUR was shown in 20 (64.5%) children in 32/62 (51.6) nephroureteral units (NUUs). In 18 NUUs, VUR was grade II/V, in 11 Grade III/V and in 3 grade IV/V, respectively. Urethra was shown in 19/31 children and in all boys, without pathological finding. In two girls spinning top urethra has been detected. Subsequent urodynamic studies revealed functional bladder problem in both.Â CONCLUSIONS: Contrast-enhanced voiding urosonography using intravesical second generation ultrasound contrast agent could be recommendÂ  as a valid alternative diagnostic modality for detecting vesicoureteral reflux and evaluation of the distal urinary tract in children, based on its radiation-free, highly efficacious, reliable, and safe characteristics.
Caïn et Abel
Authors: Grosberg Claude
Published: April 2017

Il était une fois, Caïn et Abel, les premiers frères de l’humanité balbutiante. Adonaï, père tout-puissant, fait le choix arbitraire des offrandes d’Abel, ce qui produit une envie d’une intensité ravageante chez Caïn : « Et son visage s’est défait », dit le texte de la Genèse. Caïn désire être aimé et reconnu par son père. L’angoisse suscitée par l’image de ce qui lui fait défaut et que posséderait son frère Abel, transforme son désir en une détresse muette. Passage d’un indicible à la décharge meurtrière. Caïn ne résistera pas à cette envie brûlante qui le taraude et accomplira le premier meurtre de la Genèse. L’envie, mère de la haine, engendre le meurtre fratricide, produisant un point de réel déclencheur de l’acting out et du meurtre psychique. C’est l’hypothèse que j’ai choisi de développer dans ce texte, avec les conséquences suivantes. Ce premier franchissement constituera le point d’origine des envies et rivalités fratricides,  frérocités qui se répéteront à l’envi dans les guerres à venir ; il sera le parangon de la mise en acte de la pulsion de mort inscrite au cœur de l’humain. A contrario, et dans l’après-coup, le geste de Caïn fait advenir une rupture radicale par rapport à un avant. Il construit la naissance de l’altérité, de la subjectivation et du lien social. Caïn peut dire je et avoir un point de vue sur son acte et sur l’ordre du monde ; en particulier, cela va éclairer la question de la finitude des humains et de la mort dorénavant représentable. Double mouvement, celui de l’avènement du travail de pensée et celui du travail de la culture, avec le fondement de la loi. Cette même discontinuité s’apparente à ce que nous rencontrons dans le travail analytique, effet de coupure et de franchissement dans la cure, repérable dans l’après-coup de ce qui s’est construit dans le transfert. Ce qui devient transgressif, c’est alors l’ouverture à une nouvelle réalité psychique vivante.
Il était une fois l’envie
Authors: Hassoun Pascale
Published: April 2017

L’auteur dresse trois figures de l’envie : celle du drame de l’identité, celle du refuge dans la maîtrise, et enfin, celle d’un effondrement qui, reconnu, nommé et élaboré dans le transfert, transforme le vécu de perte radicale en possibilité créatrice.
On tue Woyseck
Authors: Kaplan Leslie
Published: April 2017

Ce texte revisite la pièce fragmentaire de Büchner en la confrontant à la question de l’envie, et tente de saisir les correspondances entre l’écriture de Büchner, son parti pris esthétique fait de renversement et de condensation, et sa position éthique.
La projection de l’envie dans certaines formes de préjugés
Authors: Landa Eva
Published: April 2017

La superstition du « mauvais œil » a été examinée par Freud en lien avec le sentiment d’inquiétante étrangeté, en tant que projection de l’envie sur des porteurs de différences frappantes, cibles de préjugés. Dans la mythologie grecque, Némésis surveillait déjà l’hybris, l’orgueil démesuré. La notion d’identification projective apporte un éclairage à ces processus, dont on retrouve toujours la trace de nos jours, comme dans le cas des difficultés liées à la procréation.
Sur l’impossibilité de postuler une envie primaire
Authors: de Macedo Heitor O’Dwyer
Published: April 2017

L’auteur démontre l’impossibilité de postuler une envie primaire. Pour cela, il part de la conception freudienne de la haine, où il pointe une aporie, sinon un paradoxe : comment considérer la haine comme primaire si elle s’adresse à des objets totaux – ce qui suppose une organisation complexe et secondaire de l’espace du Moi ? Il conclut en proposant de concevoir la haine comme un opérateur primaire chez la mère dans le travail de séparation de son bébé. Et que l’envie, sœur jumelle de la haine, serait le stigmate du ratage de cette opération de séparation, de cette carence primaire, qui installe l’envieux dans le mensonge et dans l’orgueil. Concevoir l’envie primaire suppose donc de la situer dans l’espace psychique de la mère dans sa rencontre avec son nourrisson – nourrisson qui deviendra psychotique.
« My love to Yvette »
Authors: Kamieniak Jean-Pierre
Published: April 2017

Si la belle amitié liant Sigmund Freud et Yvette Guilbert est bien connue, son éclosion et sa nature le sont beaucoup moins, faisant l’objet d’un formidable malentendu : celui d’une légende inaugurée par Jones, colportée jusqu’à ce jour, laquelle vient totalement en dénaturer l’essence. Loin d’être fondé sur la séduction d’un soir par le monde interlope de la nuit parisienne, l’attachement de l’analyste à la chanteuse se construit tardivement, autour de valeurs et de souffrances partagées, face auxquelles Yvette déploie de remarquables capacités sublimatoires propres à émouvoir le savant. Aussi est-ce la naissance et l’épanouissement de cette amitié qui se voient restitués ici.
Propositions pour un programme d’agir spatial : la didactique de la géographie à l’épreuve de changements curriculaires
Authors: Thémines Jean-François
Published: April 2017

Le texte propose une analyse des cadres de référence en didactique de la géographie. L’auteur classe et répertorie les analyses didactiques de changements curriculaires en rapport avec les compétences en géographie. Puis il livre une clé de lecture de ces approches et caractérise deux topos structurants (Berthelot, 2001) : celui de la discipline scolaire et celui de l’agir spatial. L’enjeu de cette confrontation est d’établir un programme de recherche didactique concurrentiel de celui qui a été précédemment établi à partir du topos de discipline scolaire pour construire, dans le champ élargi des recherches en éducation, un programme émergent à partir du topos de l’agir spatial.
La gestion partagée des bassins hydrographiques transfrontaliers en Mésoamérique, source d’innovation dans la gouvernance de la coopération
Authors: Kauffer Edith , Medina Lucile , Rodríguez Tania
Published: April 2017

Cet article analyse les dynamiques de conflits et de coopération observables sur les bassins hydrographiques transfrontaliers, à travers des exemples pris dans la région mésoaméricaine (sud du Mexique et Amérique centrale). La gestion partagée de ces bassins constitue un enjeu majeur pour les frontières concernées. Il s’agit ici de questionner la dimension politique et sociale de la gestion des bassins transfrontaliers tant à travers les initiatives de coopération étudiées que les conflits qui peuvent opposer les acteurs en présence.
Notre djihad
Authors: Soriano Paul
Published: April 2017

L’EI conduit une guerre de mille ans dans un nouveau monde des réseaux où c’est l’ennemi qui lui fournit ses ressources, comme à un alien. Pour reconquérir nos âmes et nos territoires aliénés, nous devons à notre tour, en échange, faire notre djihad. Sur nous-mêmes.
L’éloquence du massacre
Authors: Salazar Philippe-Joseph
Published: April 2017

Le Califat inscrit la rhétorique au cœur de sa stratégie. Chaque acte de violence porte un message. Le massacre, c’est le médium.
Théâtres de guerre
Authors: Lhuisset Émeric , de Luigi Lana
Published: April 2017

Quand on photographie un combattant il prend la pose, il joue son propre rôle. Même la violence la plus crue appelle une mise en scène.
1918 : quelle victoire ?
Authors: Lecarme Jacques
Published: April 2017

Après une terrible guerre, une drôle de victoire : les vainqueurs doutent et les vaincus espèrent.
Pierre Loti
Authors: Vercier Bruno
Published: April 2017

Aujourd’hui 20 août et en prévision de ma mort, j’arrête définitivement ce journal de ma vie, commencé depuis environ quarante-cinq ans. Il ne m’intéresse plus, et n’intéresserait plus personne.
Romain Rolland
Authors: Reliquet Philippe
Published: April 2017

Il est, par son génie et pour le caractère, le plus grand homme de ce temps, l’un des plus nobles exemplaires d’humanité de tous les siècles. Deux fois grand, et par l’esprit et par le cœur, nul n’a porté plus haut, dans le mépris de l’outrage et le dédain de l’opinion, le respect de soi-même.
L’impasse criminelle
Authors: de Mijolla-Mellor Sophie
Published: April 2017

L’auteur reprend et complète des hypothèses développées dans son livre La mort donnée (Paris, PUF, 2011) au sujet de la mort donnée comme acte individuel et comme acte collectif. Elle rappelle trois motivations principales soit : tuer pour une identité, tuer pour survivre, tuer par ivresse de la toute-puissance.
À qui la faute ?
Authors: Chapellon Sébastien , Gontier Élisabeth
Published: April 2017

Freud a montré qu’une culpabilité inconsciente pouvait préexister à certains actes criminels. Selon lui, le sujet matérialise ainsi une culpabilité diffuse et très intense en la fixant sur un fait réel propre à lui valoir une punition. Toutefois, l’origine de certains crimes doit être située en-deçà de cette question de la culpabilité. À l’instar du cas présenté dans cet article, les sujets utilisent l’acte pour répéter les exactions dont ils ont eux-mêmes été victimes par le passé. Inconsciemment, ils essaient de faire sanctionner après-coup le préjudice qu’ils ont auparavant subi passivement et qu’ils ont incorporé à leur insu. En commettant leur délit, ils mettent sans le savoir en scène une position de victime qui n’a pas été reconnue en tant que telle. Seule la maîtrise active par l’acte semble permettre à ces sujets de renouer avec l’expérience insupportable de leur passivité de jadis. Ils défléchissent ainsi vers le dehors un noyau traumatique dont l’existence leur demeure inconnue. La procédure judiciaire joue en conséquence un rôle clef en permettant à ces sujets de se réapproprier les éléments traumatiques de leur histoire.
Antioxidant, Enzyme-Inhibitory and Antitumor Activity of the Wild Dietary Plant Muscari comosum (L.) Mill.
Authors: Casacchia Teresa , Sofo Adriano , Casaburi Ivan , Marrelli Mariangela , Conforti Filomena , Statti Giancarlo
Published: April 2017

Conventional medicines used to treat obesity and cancer frequently exhibit high side effects, so that researchers are focusing on new therapies and drugs based on natural products. Total extracts from bulbs of Muscari comosum were tested for (i) free radical scavenging activity, (ii) in vitro enzymatic inhibition of pancreatic α-amylase and lipase, and (iii) inhibition of the growth of breast adenocarcinoma cells. Three treatments were considered: bulbs boiled in water for 15 min (traditional cooking method; BB); bulbs steam-cooked for 15 min (alternative cooking method; SB); raw bulbs (RB). The polyphenol content and antioxidant capacity of bulb extracts were related to the inhibition of pancreatic lipase and α-amylase, whose activities have been found to have a half maximal inhibitory concentration (IC50) of 0.28, 2.14 and 3.22 mg/mL for lipase, and 0.16, 0.73 and 0.69 mg/mL for α-amylase in RB, SB and BB, respectively. The analysis on breast adenocarcinoma MCF-7 cells revealed that RB extracts, and in a lesser extent BB, exerted a dose-dependent inhibition on cell proliferation. Considering that the potential of natural products for the treatment of obesity are under exploration, M. comosum could be an excellent plant for the development of future anti-obesity drugs, also able to prevent cancer.
The role of cooperatives in sustaining the livelihoods of rural communities: The case of rural cooperatives in Shurugwi District, Zimbabwe
Authors: Mhembwe Smart , Dube Ernest
Published: April 2017

The main focus of the research was to analyse the role of cooperatives in sustaining the livelihoods of local rural communities in Shurugwi District in Zimbabwe. Descriptive survey design was used in this mixed method approach to the study. A questionnaire, interviews and observation methods were employed as the main research instruments. Purposive sampling technique was adopted and data were collected from government officials and from members of the six cooperatives in Shurugwi District. A total of 50 research participants were involved in the study. It was found that cooperatives were established as a strategy to sustain livelihoods of rural communities. With the adoption of cooperatives, people in the rural communities managed to generate employment, boost food production, empower the marginalised, especially women, and promote social cohesion and integration, thereby improving their livelihoods and reducing poverty. Most cooperatives face a number of challenges that include lack of financial support, poor management and lack of management skills, and lack of competitive markets to sell their produce. The study recommends that the government and the banking sector render financial support to cooperatives in rural communities to allow them to expand and diversify their business operations; constant training on leadership and management skills is provided to cooperatives’ members. There is also a need for cooperatives, especially those in the agricultural sector, to form some producer associations so as to easily market their produce. Lastly, the study recommends that future research should focus on investigating issues that hinder the growth of the cooperative movement in rural communities of Zimbabwe. It is hoped that policy-makers, the academia and communities would benefit from the study.
A metaphysical and neuropsychological assessment of musical tones to affect the brain, relax the mind and heal the body
Authors: Pretorius Mark
Published: April 2017

It has been empirically established through many controlled studies that one of the most rewarding experiences known to humanity is listening to music, especially because it affects various parts of the brain and causes emotional arousal. The aim of this article is to do a succinct study on music and its effect on, especially, the nervous system, by referring to various empirical studies undertaken on the subject. The article, therefore, has a twofold purpose: (1) to show that throughout history, music has played a special role in various cultures and religions, especially as a healing tool and (2) to demonstrate that sound frequencies and vibrations found in music have the potential to realign the emotions of the nervous system and bring the body back into harmony by reducing stress.Intradisciplinary and/or interdisciplinary implications: The article�s challenge and purpose are to show that science and religion are not in conflict, but rather that together they can benefit both disciplines and make better sense of complicated topics, especially those related to how natural science and religion deal with the human body and health, and its relationship to the mind.
Emission factors and light absorption properties of brown carbon from household coal combustion in China
Authors: Sun Jianzhong , Zhi Guorui , Hitzenberger Regina , Chen Yingjun , Tian Chongguo , Zhang Yayun , Feng Yanli , Cheng Miaomiao , Zhang Yuzhe , Cai Jing , Chen Feng , Qiu Yiqin , Jiang Zhiming , Li Jun , Zhang Gan , Mo Yangzhi
Published: April 2017

Abstract. Brown carbon (BrC) draws increasing attention due to its effects on climate and other environmental factors. In China, household coal burned for heating and cooking purposes releases huge amounts of carbonaceous particles every year; however, BrC emissions have rarely been estimated in a persuasive manner due to the unavailable emission characteristics. Here, seven coals jointly covering geological maturity from low to high were burned in four typical stoves as both chunk and briquette styles. The optical integrating sphere (IS) method was applied to measure the emission factors (EFs) of BrC and black carbon (BC) via an iterative process using the different spectral dependence of light absorption for BrC and BC and using humic acid sodium salt (HASS) and carbon black (CarB) as reference materials. The following results have been found: (i) the average EFs of BrC for anthracite coal chunks and briquettes are 1.08 ± 0.80 and 1.52 ± 0.16 g kg−1, respectively, and those for bituminous coal chunks and briquettes are 8.59 ± 2.70 and 4.01 ± 2.19 g kg−1, respectively, reflecting a more significant decline in BrC EFs for bituminous coals than for anthracites due to briquetting. (ii) The BrC EF peaks at the middle of coal's geological maturity, displaying a bell-shaped curve between EF and volatile matter (Vdaf). (iii) The calculated BrC emissions from China's residential coal burning amounted to 592 Gg (1 Gg  =  109 g) in 2013, which is nearly half of China's total BC emissions. (iv) The absorption Ångström exponents (AAEs) of all coal briquettes are higher than those of coal chunks, indicating that the measure of coal briquetting increases the BrC ∕ BC emission ratio and thus offsets some of the climate cooling effect of briquetting. (v) In the scenario of current household coal burning in China, solar light absorption by BrC (350–850 nm in this study) accounts for more than a quarter (0.265) of the total absorption. This implies the significance of BrC to climate modeling.
Consistent regional fluxes of CH4 and CO2 inferred from GOSAT proxy XCH4 : XCO2 retrievals, 2010–2014
Authors: Feng Liang , Palmer Paul I. , Bösch Hartmut , Parker Robert J. , Webb Alex J. , Correia Caio S. C. , Deutscher Nicholas M. , Domingues Lucas G. , Feist Dietrich G. , Gatti Luciana V. , Gloor Emanuel , Hase Frank , Kivi Rigel , Liu Yi , Miller John B. , Morino Isamu , Sussmann Ralf , Strong Kimberly , Uchino Osamu , Wang Jing , Zahn Andreas
Published: April 2017

Abstract. We use the GEOS-Chem global 3-D model of atmospheric chemistry and transport and an ensemble Kalman filter to simultaneously infer regional fluxes of methane (CH4) and carbon dioxide (CO2) directly from GOSAT retrievals of XCH4 : XCO2, using sparse ground-based CH4 and CO2 mole fraction data to anchor the ratio. This work builds on the previously reported theory that takes into account that (1) these ratios are less prone to systematic error than either the full-physics data products or the proxy CH4 data products; and (2) the resulting CH4 and CO2 fluxes are self-consistent. We show that a posteriori fluxes inferred from the GOSAT data generally outperform the fluxes inferred only from in situ data, as expected. GOSAT CH4 and CO2 fluxes are consistent with global growth rates for CO2 and CH4 reported by NOAA and have a range of independent data including new profile measurements (0–7 km) over the Amazon Basin that were collected specifically to help validate GOSAT over this geographical region. We find that large-scale multi-year annual a posteriori CO2 fluxes inferred from GOSAT data are similar to those inferred from the in situ surface data but with smaller uncertainties, particularly over the tropics. GOSAT data are consistent with smaller peak-to-peak seasonal amplitudes of CO2 than either the a priori or in situ inversion, particularly over the tropics and the southern extratropics. Over the northern extratropics, GOSAT data show larger uptake than the a priori but less than the in situ inversion, resulting in small net emissions over the year. We also find evidence that the carbon balance of tropical South America was perturbed following the droughts of 2010 and 2012 with net annual fluxes not returning to an approximate annual balance until 2013. In contrast, GOSAT data significantly changed the a priori spatial distribution of CH4 emission with a 40 % increase over tropical South America and tropical Asia and a smaller decrease over Eurasia and temperate South America. We find no evidence from GOSAT that tropical South American CH4 fluxes were dramatically affected by the two large-scale Amazon droughts. However, we find that GOSAT data are consistent with double seasonal peaks in Amazonian fluxes that are reproduced over the 5 years we studied: a small peak from January to April and a larger peak from June to October, which are likely due to superimposed emissions from different geographical regions.
Ice nucleating particles over the Eastern Mediterranean measured by unmanned aircraft systems
Authors: Schrod Jann , Weber Daniel , Drücke Jaqueline , Keleshis Christos , Pikridas Michael , Ebert Martin , Cvetković Bojan , Nickovic Slobodan , Marinou Eleni , Baars Holger , Ansmann Albert , Vrekoussis Mihalis , Mihalopoulos Nikos , Sciare Jean , Curtius Joachim , Bingemer Heinz G.
Published: April 2017

Abstract. During an intensive field campaign on aerosol, clouds, and ice nucleation in the Eastern Mediterranean in April 2016, we measured the abundance of ice nucleating particles (INPs) in the lower troposphere from unmanned aircraft systems (UASs). Aerosol samples were collected by miniaturized electrostatic precipitators onboard the UASs at altitudes up to 2.5 km. The number of INPs in these samples, which are active in the deposition and condensation modes at temperatures from −20 to −30 °C, were analyzed immediately after collection on site using the ice nucleus counter FRIDGE (FRankfurt Ice nucleation Deposition freezinG Experiment). During the 1-month campaign, we encountered a series of Saharan dust plumes that traveled at several kilometers' altitude. Here we present INP data from 42 individual flights, together with aerosol number concentrations, observations of lidar backscattering, dust concentrations derived by the dust transport model DREAM (Dust Regional Atmospheric Model), and results from scanning electron microscopy. The effect of the dust plumes is reflected by the coincidence of INPs with the particulate matter (PM), the lidar signal, and the predicted dust mass of the model. This suggests that mineral dust or a constituent related to dust was a major contributor to the ice nucleating properties of the aerosol. Peak concentrations of above 100 INPs std L−1 were measured at −30 °C. The INP concentration in elevated plumes was on average a factor of 10 higher than at ground level. Since desert dust is transported for long distances over wide areas of the globe predominantly at several kilometers' altitude, we conclude that INP measurements at ground level may be of limited significance for the situation at the level of cloud formation.
Near real time processing of ceilometer network data: characterizing
an extraordinary dust outbreak over the Iberian Peninsula
Authors: Cazorla Alberto , Casquero-Vera Juan Andrés , Román Roberto , Guerrero-Rascado Juan Luis , Toledano Carlos , Cachorro Victoria E. , Orza José Antonio G. , Cancillo María Luisa , Serrano Antonio , Titos Gloria , Pandolfi Marco , Alastuey Andrés , Hanrieder Natalie , Alados-Arboledas Lucas
Published: April 2017

Abstract. The interest on the use of ceilometers for optical aerosol characterization has increased in the last few years. They operate continuously almost unattended and are also much less expensive than lidars, hence they can be distributed in dense networks over large areas. However, due to the low signal-to-noise-ratio it is not always possible to obtain particle backscatter coefficient profiles, and the vast amount of data generated requires an automated and unsupervised method that ensures the quality of the profiles inversions. In this work a method that uses aerosol optical depth (AOD) measurements from the AERONET network is applied for the calibration and automated quality assurance of inversion of ceilometer profiles. The method is compared with independent inversions obtained by co-located multiwavelength lidar measurements and a difference up to 15 % in backscatter is found between both instruments. This method is continuously and automatically applied to the Iberian Ceilometer Network (ICENET) and a case example during an unusually intense dust outbreak that affected the Iberian Peninsula on 20 February 2016 and lasted until 24 February 2016 is shown. Results reveal that it is possible to obtain a quantitative optical aerosol characterization (particle backscatter coefficient) with ceilometers over large areas and this information has a great potential for alert systems and model assimilation and evaluation.
Biomass burning CCNs enhance the dynamics of a Mesoscale
Convective System over the La Plata Basin: a numerical approach
Authors: Camponogara Gláuber , Silva Dias Maria Assunção Faus , Carrió Gustavo G.
Published: April 2017

Abstract. High aerosol loadings are discharged into the atmosphere every year by biomass burning in the Amazon and Central Brazil during the dry season (July–December). These particles, suspended in the atmosphere, can be carried via a low level jet toward the La Plata Basin, one of the largest hydrographic basins in the world. Once they reach this region, the aerosols can affect mesoscale convective systems (MCS), whose frequency is higher during the spring and summer over the basin. The present study is one of the first that seeks to understand the microphysical effects of biomass burning aerosols from the Amazon Basin on mesoscale convective systems over the La Plata Basin. We performed numerical simulations initialized with idealized CCN profiles for an MCS case observed over the La Plata Basin on 21 September 2010. The experiments reveal an important link between CCN number concentration and MCS dynamics, where stronger downdrafts were observed under higher amounts of aerosols, generating more updraft cells in response. Moreover, the simulations show higher amounts of precipitation as the CCN concentration increases. Despite the model’s uncertainties and limitations, these results represent an important step toward the understanding of possible impacts on the Amazon biomass burning aerosols over neighboring regions such as the La Plata Basin.
An intercalibrated dataset of total column water vapour and wet tropospheric correction based on MWR on board ERS-1, ERS-2, and Envisat
Authors: Bennartz Ralf , Höschen Heidrun , Picard Bruno , Schröder Marc , Stengel Martin , Sus Oliver , Bojkov Bojan , Casadio Stefano , Diedrich Hannes , Eliasson Salomon , Fell Frank , Fischer Jürgen , Hollmann Rainer , Preusker Rene , Willén Ulrika
Published: April 2017

Abstract. The microwave radiometers (MWRs) on board the European Remote Sensing Satellites 1 and 2 (ERS-1 and ERS-2) and Envisat provide a continuous time series of brightness temperature observations between 1991 and 2012. Here we report on a new total column water vapour (TCWV) and wet tropospheric correction (WTC) dataset that builds on this time series. We use a one-dimensional variational approach to derive TCWV from MWR observations and ERA-Interim background information. A particular focus of this study lies on the intercalibration of the three different instruments, which is performed using constraints on liquid water path (LWP) and TCWV. Comparing our MWR-derived time series of TCWV against TCWV derived from Global Navigation Satellite System (GNSS) we find that the MWR-derived TCWV time series is stable over time. However, observations potentially affected by precipitation show a degraded performance compared to precipitation-free observations in terms of the accuracy of retrieved TCWV. An analysis of WTC shows further that the retrieved WTC is superior to purely ERA-Interim-derived WTC for all satellites and for the entire time series. Even compared to the European Space Agency's (ESA) operational WTC retrievals, which incorporate in addition to MWR additional observational data, the here-described dataset shows improvements in particular for the mid-latitudes and for the two earlier satellites, ERS-1 and ERS-2. The dataset is publicly available under doi:10.5676/DWD_EMIR/V001 (Bennartz et al., 2016).
Inverse-model estimates of the ocean's coupled phosphorus, silicon,
and iron cycles
Authors: Pasquier Benoît , Holzer Mark
Published: April 2017

Abstract. The ocean's nutrient cycles are important for the carbon balance of the climate system and for shaping the ocean's distribution of dissolved elements. Dissolved iron (dFe) is a key limiting micronutrient, but iron scavenging is observationally poorly constrained leading to large uncertainties in the external sources of iron and hence in the state of the marine iron cycle. Here we build a model of the ocean's coupled phosphorus, silicon, and iron cycles embedded in a data-assimilated steady-state global ocean circulation. The model includes the redissolution of scavenged iron, parameterization of subgrid topography, and small, large, and diatom phytoplankton functional classes. Phytoplankton concentrations are implicitly represented in the parameterization of biological nutrient utilization through an equilibrium logistic model. Our coupled nutrient model thus carries only three nutrient tracers whose three-dimensional steady-state distributions can be found efficiently using a Newton solver. The very efficient numerics allow us to use the model in inverse mode to objectively constrain many biogeochemical parameters by minimizing the mismatch between modelled and observed nutrient and phytoplankton concentrations. We consider a family of possible solutions corresponding to a wide range of external iron source strengths. Iron source and sink parameters cannot jointly be optimized because of local compensation between regeneration, recycling, and scavenging. All optimized solutions have a similar mismatch with the observed nutrient concentrations and very similar large-scale dFe distributions. However, the relative contributions of aeolian, sedimentary, and hydrothermal iron to the total dFe concentration differ widely depending on the sources. Both the magnitude and pattern of carbon and opal export are well constrained with global values of (10.3 ± 0.4) Pg C yr−1 and (171. ± 3.) Tmol Si yr−1. We diagnose the carbon and opal export supported by aeolian, sedimentary, and hydrothermal iron. The geographic patterns of the export supported by each iron type are well constrained across the family of solutions. Sedimentary-iron supported export is important in shelf and large-scale upwelling regions, while hydrothermal iron contributes to export mostly in the Southern Ocean. The globally integrated export supported by a given iron type varies systematically with the fractional contribution of its source to the total iron source. Aeolian iron is most efficient in supporting export in the sense that its fractional contribution to export exceeds its fractional contribution to the total source by as much as ~ 30 % for carbon and ~ 20 % for opal export. Conversely, sedimentary and hydrothermal iron are less efficient with a fractional export that is less than their fractional sources. For the same fractional contribution to the total source, hydrothermal iron is less efficient than sedimentary iron for supporting carbon export but about equally efficient for supporting opal export.
High organic inputs explain shallow and deep SOC storage in a long-term agroforestry system – Combining experimental and modeling approaches
Authors: Cardinael Rémi , Guenet Bertrand , Chevallier Tiphaine , Dupraz Christian , Cozzi Thomas , Chenu Claire
Published: April 2017

Abstract. Agroforestry is an increasingly popular farming system enabling agricultural diversification and providing several ecosystem services. In agroforestry systems, soil organic carbon (SOC) stocks are generally increased, but it is difficult to disentangle the different factors responsible for this storage. Organic carbon (OC) inputs to the soil may be larger, but SOC decomposition rates may be modified owing to microclimate, physical protection, or priming effect from roots, especially at depth. We used an 18-year-old silvoarable system associating hybrid walnut trees (Juglans regia × nigra) and durum wheat (Triticum turgidum L. subsp. durum), and an adjacent agricultural control plot to quantify all OC inputs to the soil – leaf litter, tree fine root senescence, crop residues, and tree row herbaceous vegetation –, and measure SOC stocks down 2 m depth at varying distances from the trees. We then proposed a model that simulates SOC dynamics in agroforestry accounting for both the whole soil profile and the lateral spatial heterogeneity. OC inputs to soil were increased by about 40 % (+1.11 t C ha−1 yr−1) down to 2 m depth in the agroforestry plot compared to the control, resulting in an additional SOC stock of 6.3 t C ha−1 down to 1 m depth. The model described properly the measured SOC stocks and distribution with depth. It showed that the increased inputs of fresh biomass to soil explained the observed additional SOC storage in the agroforestry plot. Moreover, modeling revealed a strong priming effect that would reduce the potential SOC storage due to higher organic inputs in the agroforestry system by 75 to 90 %. This result questions the potential of soils to store large amounts of carbon, especially at depth. Deep-rooted trees modify OC inputs to soil, a process that deserves further studies given its potential effects on SOC dynamics.
An Evaluation and Implementation of the Regional Coupled
Ice-Ocean Model of the Baltic Sea
Authors: Jakacki Jaromir , Meler Sebastian
Published: April 2017

Abstract. A three dimensional, regional coupled ice-ocean model based on the open-source Community Earth System Model has been developed and implemented for the Baltic Sea. The model consists of 66 vertical levels and has a horizontal resolution of approx. 2.3 km. The paper focuses on sea ice component results but the main changes have been introduced in the ocean part of the coupled model. The hydrodynamic part, being one of the most important components, has been also presented and validated. The ice model results were validated against the radar and satellite data, and the method of validation based on probability was introduced. In the last two decades satellite and model results show an increase in the ice extent over the whole Baltic Sea, which is an evidence of a negative trend in air temperature in recent decades and increasing of winter discharge from the catchment area.
Structure and functioning of the acid-base system in the Baltic Sea
Authors: Kuliński Karol , Schneider Bernd , Szymczycha Beata , Stokowski Marcin
Published: April 2017

Abstract. The marine acid-base system is relatively well understood for oceanic waters. Its structure and functioning is less obvious for the coastal and shelf seas due to the number of regionally specific anomalies. In this review article we collect and integrate existing knowledge on the acid-base system in the Baltic Sea. Hydrographical and biogeochemical characteristics of the Baltic Sea, as manifested in horizontal and vertical salinity gradients, permanent stratification of the water column, eutrophication, high organic matter concentrations and high anthropogenic pressure, makes the acid-base system complex. We summarize in this study the general knowledge on the marine acid-base system as well as we describe the peculiarities identified and reported for the Baltic Sea specifically. In this context we discuss issues such as: dissociation constants in the brackish water, different chemical alkalinity models including contributions by organic acid-base systems, long term changes of total alkalinity, anomalies of borate alkalinity and thee acid-base effects of biomass production and mineralization. Finally, we identify research gaps and specify bottlenecks concerning Baltic Sea acid-base system.
Assessment of extreme hydrological conditions in the Bothnian Bay, Baltic Sea, and the impact of the nuclear power plant “Hanhikivi-1” on the local thermal regime
Authors: Dvornikov Anton Y. , Martyanov Stanislav D. , Ryabchenko Vladimir A. , Eremina Tatjana R. , Isaev Alexey V. , Sein Dmitry V.
Published: April 2017

Abstract. The results of the study aimed to assess the influence of future nuclear power plant Hanhikivi-1 upon the local thermal conditions in the Bothnian Bay in the Baltic Sea are presented. A number of experiments with different numerical models were also carried out in order to estimate the extreme hydro-meteorological conditions in the area of the construction. The numerical experiments were fulfilled both with analytically specified external forcing and with real external forcing for 2 years: a cold year (2010) and a warm year (2014). The study has shown that the extreme values of sea level and water temperature and the characteristics of wind waves and sea ice in the vicinity of the future nuclear power plant can be significant and sometimes catastrophic. Permanent release of heat into the marine environment from an operating nuclear power plant will lead to a strong increase in temperature and the disappearance of ice cover within a 2 km vicinity of the station. These effects should be taken into account when assessing local climate changes in the future.
Geomorphometric delineation of floodplains and
terraces from objectively defined topographic
thresholds
Authors: Clubb Fiona J. , Mudd Simon M. , Milodowski David T. , Valters Declan A. , Slater Louise J. , Hurst Martin D. , Limaye Ajay B.
Published: April 2017

Abstract. Floodplain and terrace features can provide information about current and past fluvial processes, including channel response to varying discharge and sediment flux; sediment storage; and the climatic or tectonic history of a catchment. Previous methods of identifying floodplain and terraces from digital elevation models (DEMs) tend to be semi-automated, requiring the input of independent datasets or manual editing by the user. In this study we present a new, fully automated method of identifying floodplain and terrace features based on two thresholds: local gradient, and elevation compared to the nearest channel. These thresholds are calculated statistically from the DEM using quantile-quantile plots and do not need to be set manually for each landscape in question. We test our method against field-mapped floodplain initiation points, published flood hazard maps, and digitised terrace surfaces from seven field sites from the US and one field site from the UK. For each site, we use high-resolution DEMs derived from light detection and ranging (LiDAR) where available, as well as coarser resolution national datasets to test the sensitivity of our method to grid resolution. We find that our method is successful in extracting floodplain and terrace features compared to the field-mapped data from the range of landscapes and grid resolutions tested. The method is most accurate in areas where there is a contrast in slope and elevation between the feature of interest and the surrounding landscape, such as confined valley settings. Our method provides a new tool for rapidly and objectively identifying floodplain and terrace features on a landscape scale, with applications including flood risk mapping, reconstruction of landscape evolution, and quantification of sediment storage routing.
A representation of the phosphorus cycle for ORCHIDEE (revision
3985)
Authors: Goll Daniel S. , Vuichard Nicolas , Maignan Fabienne , Jornet-Puig Albert , Sardans Jordi , Violette Aurelie , Peng Shushi , Sun Yan , Kvakic Marko , Guimberteau Matthieu , Guenet Bertrand , Zaehle Soenke , Peñuelas Josep , Janssens Ivan , Ciais Philippe
Published: April 2017

Abstract. Land surface models rarely incorporate the terrestrial phosphorus cycle and its interactions with the carbon cycle, despite the extensive scientific debate about the importance of nitrogen and phosphorus supply for future land carbon uptake. We describe a representation of the terrestrial phosphorus cycle for the land surface model ORCHIDEE, and evaluate it with data from nutrient manipulation experiments along a soil formation chronosequence in Hawaii. ORCHIDEE accounts for influence of nutritional state of vegetation on tissue nutrient concentrations, photosynthesis, plant growth, biomass allocation, biochemical (phosphatase-mediated) mineralization and biological nitrogen fixation. Changes in nutrient content (quality) of litter affect the carbon use efficiency of decomposition and in return the nutrient availability to vegetation. The model explicitly accounts for root zone depletion of phosphorus as a function of root phosphorus uptake and phosphorus transport from soil to the root surface. The model captures the observed differences in the foliage stoichiometry of vegetation between an early (300yr) and a late stage (4.1 Myr) of soil development. The contrasting sensitivities of net primary productivity to the addition of either nitrogen, phosphorus or both among sites are in general reproduced by the model. As observed, the model simulates a preferential stimulation of leaf level productivity when nitrogen stress is alleviated, while leaf level productivity and leaf area index are stimulated equally when phosphorus stress is alleviated. The nutrient use efficiencies in the model are lower as observed primarily due to biases in the nutrient content and turnover of woody biomass. We conclude that ORCHIDEE is able to reproduce the shift from nitrogen to phosphorus limited net primary productivity along the soil development chronosequence, as well as the contrasting responses of net primary productivity to nutrient addition.
Initiation of a major calving event on the Bowdoin Glacier captured by UAV photogrammetry
Authors: Jouvet Guillaume , Weidmann Yvo , Seguinot Julien , Funk Martin , Abe Takahiro , Sakakibara Daiki , Seddik Hakime , Sugiyama Shin
Published: April 2017

Abstract. In this paper, we analyse the calving activity of the Bowdoin Glacier, north-western Greenland, in 2015 by combining satellite images, UAV (unmanned aerial vehicle) photogrammetry and ice flow modelling. In particular, a high-resolution displacement field is inferred from UAV orthoimages taken immediately before and after the initiation of a large fracture, which induced a major calving event. A detailed analysis of the strain rate field allows us to accurately map the path taken by the opening crack. Modelling results reveal (i) that the crack was more than half-thickness deep, filled with water and getting irreversibly deeper when it was captured by the UAV and (ii) that the crack initiated in an area of high horizontal shear caused by a local basal bump immediately behind the current calving front. The asymmetry of the bed at the front explains the systematic calving pattern observed in May and July–August 2015. As a corollary, we infer that the calving front of the Bowdoin Glacier is currently stabilized by this bedrock bump and might enter into an unstable mode and retreat rapidly if the glacier keeps thinning in the coming years. Beyond this outcome, our study demonstrates that the combination of UAV photogrammetry and ice flow modelling is a promising tool to horizontally and vertically track the propagation of fractures responsible for large calving events.
Progressive Damage Modeling of Fiberglass/Epoxy Composites
with Manufacturing Induced Waves Common to Wind Turbine Blades
Authors: Nelson Jared W. , Riddle Trey W. , Cairns Douglas S.
Published: April 2017

Abstract. As part of the Blade Reliability Collaborative, the Montana State University Composites Group has investigated the effects of manufacturing defects. To better understand and predict these effects, various progressive damage modeling approaches were investigated. While the use of damage modeling has increased with improved computational capabilities, they are often performed for worst-case scenarios where damage or defects are replaced with notches or holes. To contribute to the establishment of a protocol understanding and quantifying the effects of these defects, a three-round study was performed using continuum, discrete, and combined damage modeling. This approach relied on a systematically comparing consistency, accuracy and predictive capability for each model. These models were constructed to match the coupons from, and compare the results to, the characterization and material testing study. A standard defect case was chosen and initially used for each modeling approach to perform the qualitative and quantitative comparisons. It was found that while each model was able to show certain attributes, the most consistent, accurate, and predictive model was based on a combined continuum/discrete method. Overall, the results indicate that this combined approach may provide insight into blade performance with known defects when used in conjunction with a probabilistic flaw framework.