Rainwater propagation through snowpack during rain-on-snow sprinkling experiments under different snow conditions

The mechanisms of rainwater propagation and runoff generation during rain-on-snow (ROS) events are still insufficiently known. Understanding storage and transport of liquid water in natural snowpacks is crucial, especially for forecasting of natural hazards such as floods and wet snow avalanches. In this study, propagation of rainwater through snow was investigated by sprinkling experiments with deuterium-enriched water and applying an alternative hydrograph separation technique on samples collected from the snowpack runoff. This allowed us to quantify the contribution of rainwater, snowmelt and initial liquid water released from the snowpack. Four field experiments were carried out during winter 2015 in the vicinity of Davos, Switzerland. Blocks of natural snow were isolated from the surrounding snowpack to inhibit lateral exchange of water and were exposed to artificial rainfall using deuterium-enriched water. The experiments were composed of four 30 min periods of sprinkling, separated by three 30 min breaks. The snowpack runoff was continuously gauged and sampled periodically for the deuterium signature. At the onset of each experiment antecedent liquid water was first pushed out by the sprinkling water. Hydrographs showed four pronounced peaks corresponding to the four sprinkling bursts. The contribution of rainwater to snowpack runoff consistently increased over the course of the experiment but never exceeded 86 %. An experiment conducted on a non-ripe snowpack suggested the development of preferential flow paths that allowed rainwater to efficiently propagate through the snowpack limiting the time for mass exchange processes to take effect. In contrast, experiments conducted on ripe isothermal snowpack showed a slower response behaviour and resulted in a total runoff volume which consisted of less than 50 % of the rain input

Semantic Web integration of Cheminformatics resources with the SADI framework

<p>Abstract</p> <p>Background</p> <p>The diversity and the largely independent nature of chemical research efforts over the past half century are, most likely, the major contributors to the current poor state of chemical computational resource and database interoperability. While open software for chemical format interconversion and database entry cross-linking have partially addressed database interoperability, computational resource integration is hindered by the great diversity of software interfaces, languages, access methods, and platforms, among others. This has, in turn, translated into limited reproducibility of computational experiments and the need for application-specific computational workflow construction and semi-automated enactment by human experts, especially where emerging interdisciplinary fields, such as systems chemistry, are pursued. Fortunately, the advent of the Semantic Web, and the very recent introduction of RESTful Semantic Web Services (SWS) may present an opportunity to integrate all of the existing computational and database resources in chemistry into a machine-understandable, unified system that draws on the entirety of the Semantic Web.</p> <p>Results</p> <p>We have created a prototype framework of Semantic Automated Discovery and Integration (SADI) framework SWS that exposes the QSAR descriptor functionality of the Chemistry Development Kit. Since each of these services has formal ontology-defined input and output classes, and each service consumes and produces RDF graphs, clients can automatically reason about the services and available reference information necessary to complete a given overall computational task specified through a simple SPARQL query. We demonstrate this capability by carrying out QSAR analysis backed by a simple formal ontology to determine whether a given molecule is drug-like. Further, we discuss parameter-based control over the execution of SADI SWS. Finally, we demonstrate the value of computational resource envelopment as SADI services through service reuse and ease of integration of computational functionality into formal ontologies.</p> <p>Conclusions</p> <p>The work we present here may trigger a major paradigm shift in the distribution of computational resources in chemistry. We conclude that envelopment of chemical computational resources as SADI SWS facilitates interdisciplinary research by enabling the definition of computational problems in terms of ontologies and formal logical statements instead of cumbersome and application-specific tasks and workflows.</p

SAWSDL: Semantic Annotations for WSDL and XML Schema

Web services are important for creating distributed applications on the Web. In fact, they're a key enabler for service-oriented architectures that focus on service reuse and interoperability. The World Wide Web Consortium (W3C) has recently finished work on two important standards for describing Web services the Web Services Description Language (WSDL) 2.0 and Semantic Annotations for WSDL and XML Schema (SAWSDL). Here, the authors discuss the latter, which is the first standard for adding semantics to Web service descriptions

Adapting SAWSDL for semantic annotations of RESTful services

RESTful services are increasingly been adopted as a suitable lightweight solution for creating service-based applications on the Web. However, most often these services lack any machine-processable description and therefore a significant human labour has to be devoted to locating existing services, understanding their documentation, and implementing software that uses them. In order to increase the automation of these tasks, we present an integrated lightweight approach for the creation of semantic RESTful service descriptions. Our work is based on hRESTS, a microformat for including machine-readable descriptions of RESTful service within existing HTML service documentation. We complement hRESTS by the MicroWSMO microformat, which uses SAWSDL-like hooks to add semantic annotations. Finally, we present SWEET–Semantic Web sErvices Editing Tool–which effectively supports users in creating semantic descriptions of RESTful services based on the aforementioned technologies

Uso de isótopos estáveis da água para um melhor entendimento dos processos hidrogeológicos no Haiti: visão geral de dados de δ18O e δ2H existentes

International audienceIsotope hydrological studies carried out since 1987 in Haiti have proven to be effective in improving conceptual models of the principal aquifers in this Caribbean island nation. However, many of these studies have been limited and are mostly unpublished. It is, therefore, important to share the available datasets with scientists and water managers to support further studies and guide decision-making. Eleven datasets were compiled in a unique database for continued advancement and application. This dataset now contains 248 δ 18 O and δ 2 H results from water samples collected at 190 locations throughout the country. δ 18 O and δ 2 H values range, respectively, from –3.8 to –8.95‰ and –67.4 to –16.8‰ for precipitation ( n = 5), 0.9 to 2.76‰ and 8.8 to 18.4‰ for lakes ( n = 4), –2.61 to 4.98‰ and –26.63 to 28.2‰ for rivers ( n = 11), –5.11 to –2.6‰ and –29.8 to –6.9‰ for springs ( n = 82) excluding hot springs, and –5.1 to –1.37‰ and –29.4 to –2.9‰ for boreholes ( n = 142). The overall presentation of the available data is complemented with an overview of the studies in which stable isotope data acquisition was performed. The global dataset is presented under three primary contexts: (1) elaboration of a local isotope meteoric water line of equation δ 2 H = 7.2δ 18 O + 8.8 supported with data predominately from the Ouest jurisdictional department, (2) spatial variability analysis of the dataset, and (3) definition of the altitude gradient (per 100 m) using freshwater springs of the Plaine du Cul-de-Sac/Massif de la Selle area of –6.67‰ for δ 2 H and –0.09‰ for δ 18 O.Los estudios hidrológicos isotópicos realizados desde 1987 en Haití han demostrado ser eficaces para mejorar los modelos conceptuales de los principales acuíferos de esta nación insular del Caribe. Sin embargo, muchos de estos estudios han sido limitados y en su mayoría no se han publicado. Por lo tanto, es importante compartir los conjuntos de datos disponibles con los científicos y los gestores del agua para apoyar nuevos estudios y orientar la toma de decisiones. Se recopilaron once conjuntos de datos en una base de datos única para su avance y aplicación ulterior. Este conjunto de datos contiene ahora 248 resultados de δ 18 O y δ 2 H de muestras de agua recogidas en 190 lugares de todo el país. Los valores de δ 18 O y δ 2 H varían, respectivamente, de –3.8 a –8.95‰ y de –67.4 a –16.8‰ para las precipitaciones ( n = 5), de 0.9 a 2.76‰ y de 8.8 a 18.4‰ para los lagos ( n = 4), de –2.61 a 4.98‰ y de –26.63 a 28.2‰ para los ríos ( n = 11), –5.11 a –2.6‰ y –29.8 a –6.9‰ para los manantiales ( n = 82), excluyendo las fuentes termales, y –5.1 a –1.37‰ y –29.4 a –2.9‰ para los pozos de sondeo ( n = 142). La presentación global de los datos disponibles se complementa con un resumen de los estudios en los que se realizó la adquisición de datos de isótopos estables. El conjunto de datos globales se presenta en tres contextos principales: (1) elaboración de una línea local de isótopos del agua meteórica de ecuación δ 2 H = 7.2 δ 18 O + 8.8 apoyada con datos predominantemente del departamento jurisdiccional Ouest, (2) análisis de la variabilidad espacial del conjunto de datos, y (3) definición del gradiente de altitud (por 100 m) utilizando manantiales de agua dulce de la zona de Plaine du Cul-de-Sac/Massif de la Selle de –6.67‰ para δ 2 H y –0.09‰ para δ 18 O.Les études hydrogéologiques menées depuis 1987 à Haïti ont montré leur intérêt pour l’amélioration des modèles conceptuels des principaux aquifères de ce pays insulaire des Caraïbes. Il est donc important de partager ces données avec les scientifiques et les gestionnaires de la ressource en eau pour appuyer d’autres projets et guider la prise de décision. Onze jeux de données ont été compilés dans une base de données unique évolutive à visée opérationnelle. Ce jeu de données contient aujourd’hui 248 résultats d’analyses de δ 18 O et δ 2 H provenant d’échantillons d’eau collectés sur 190 sites répartis dans tout le pays. Les valeurs de δ 18 O et δ 2 H s’étendent respectivement de –3.8 à –8.95‰ et –67.4 à –16.8‰ pour les pluies ( n = 5), 0.9 à 2.76‰ et 8.8 à 18.4‰ pour les lacs ( n = 4), –2.61 à 4.98‰ et –26.63 à 28.2‰ pour les rivières ( n = 11), –5.11 à –2.6‰ et –29.8 à –6.9‰ pour les sources ( n = 82) en excluant les sources chaudes, et –5.1 à –1.37‰ et –29.4 à –2.9‰ pour les forages ( n = 142). La présentation générale des données est complétée par un résumé des études ayant permis l’acquisition des données en isotopes stables. Le jeu de données complet est présenté à l’aide de trois principaux aspects: (1) élaboration de la droite météorique locale des pluies d’équation δ 2 H = 7.2δ 18 O + 8.8 s’appuyant sur des données principalement du département de l’Ouest, (2) analyse de la variabilité spatiale du jeu de données, et (3) définition d’un gradient d’altitude (par 100 m) utilisant les eaux douces des sources de la plaine du Cul-de-Sac/Massif de la Selle de –6.67‰ pour le δ 2 H et –0.09‰ pour le δ 18 O.Estudos hidrológicos isotópicos conduzidos no Haiti desde 1987 têm provado serem eficientes para melhorar os modelos conceituais dos principais aquíferos dessa nação das ilhas caribenhas. Porém, muitos destes estudos têm sido limitados e são majoritariamente não publicados. É importante, portanto, compartilhar os conjuntos de dados disponíveis com cientistas e gestores hídricos para incentivar mais estudos e guiar tomadas de decisão. Onze conjuntos de dados foram compilados em um único banco de dados para continuar seu avanço e aplicação. Este novo conjunto de dados agora contém 248 resultados de δ 18 O e δ 2 H de amostras de água, coletadas em 190 locais pelo país. Os valores de δ 18 O e δ 2 H variam, respectivamente, de 3.8 a –8.95‰ e –67.4 a 16.8‰ para precipitação ( n = 5), 0.9 a 2.76‰ e 8.8 a 18.4‰ para lagos ( n = 4), –2.61 a 4.98‰ e –26.63 a 28.2‰ para rios ( n = 11), –5.11 a –2.6‰ e –29.8 a –6.9‰ para nascentes ( n = 82), excluindo fontes termais, e –5.1 a –1.37‰ e –29.4 a 2.9‰ para poços ( n = 142). A apresentação geral dos dados disponíveis é complementada com uma visão geral dos estudos em que houveram coleta de dados de isótopos estáveis. O conjunto global dos dados é apresentado sob três contextos primários: (1) elaboração de uma reta meteórica local de equação δ 2 H = 7.2δ 18 O +8.8 baseada predominantemente nos dados do departamento jurisdicional de Ouest, (2) análise da variabilidade espacial do conjunto de dados, e (3) definição da altitude do gradiente (a cada 100 m) utilizando fontes de água doce da área do Plaine du Cul-de-Sac/Massif de la Selle de –6.67‰ para δ 2 H e –0.09‰ para δ 18 O

A comparative study in modelling runoff and its components in two mountainous catchments

In mountainous catchments the quality of runoff modelling depends strongly on the assessment of the spatial differences in the generation of the various runoff components and of the flow paths as coupled with the amount and intensity of precipitation and/or the snow melting. These catchments are also suitable for the intercomparison of different kinds of hydrological models, particularly of different approaches for the simulation of runoff generation. Two differently structured catchment models were applied on the pre-alpine Rietholzbach research catchment (3·2 km2) within the period 1981-98 and on the high-alpine Dischmabach catchment (43 km2) within the period 1981-96 for the simulation of hydrological processes and of the runoff hydrographs. The models adopted are the more physically based WaSiM-ETH model, with grid-oriented computation of the water balance elements, and the rather conceptual PREVAH model, based on hydrological response units. The simulation results and the differences resulting from the application of the two models are discussed and compared with the observed catchment discharges, with measurements of evapotranspiration, soil moisture, outflow of a lysimeter, and of groundwater levels in three access tubes. The model intercomparison indicates that the two approaches for determining runoff generation with different degrees of complexity performed with similar statistical efficiency over a period longer than 15 years. The analysis of the simulated runoff components shows that the interflow is the main runoff component and that the portion of the runoff components depends strongly on the approach used. The snowmelt model component is of decisive importance in the snowmelt season and needs to take into account the role of air temperature and radiation for simulating runoff generation in a spatially distributed manne