An interactive visual analysis tool for investigating teleconnections in climate simulations

Teleconnections refer to links between regions that are distant to each other, but nevertheless exhibit some relation. The study of such teleconnections is a well-known task in climate research. Climate simulation shall model known teleconnections. Detecting teleconnections in climate simulations is a crucial aspect in judging the quality of the simulation output. It is common practice to run scripts to execute a sequence of analysis steps on the climate simulations to search for teleconnections. Such a scripting approach is not flexible and targeted towards one specific goal. It is desirable to have one tool that allows for a flexible analysis of all teleconnection patterns with a dataset. We present such a tool, where the extracted information is provided in an intuitive visual form to users, who then can interactively explore the data. We developed an analysis workflow that is modeled around four views showing different facets of the data with coordinated interaction. We present a teleconnection study with simulation ensembles and reanalysis data obtained by data assimilation to observe how well the teleconnectivity patterns match and to demonstrate the effectiveness of our tool

Hydrogen induced structural phase transformation in ScNiSn-based intermetallic hydride characterized by experimental and computational studies

Understanding an interrelation between the structure, chemical composition and hydrogenation properties of intermetallic hydrides is crucial for the improvement of their hydrogen storage performance. Ability to form the hydrides and to tune the thermodynamics and kinetics of their interaction with hydrogen is related to their chemical composition. Some features of the metal–hydrogen interactions remain however poorly studied, including chemistry of Sc-containing hydrides. ZrNiAl-type ScNiSn-based intermetallic hydride has been probed in the present work using a broad range of experimental techniques including Synchrotron and Neutron Powder Diffraction, $^{119}$Sn Möessbauer Spectroscopy, hydrogenation at pressures reaching several kbar H$_2$ and hydrogen Thermal Desorption Spectroscopy studies. Computational DFT calculations have been furthermore performed. This allowed to establish the mechanism of the phase-structural transformation and electronic structure changes causing a unique contraction of the metal lattice of intermetallic alloy and the formation of the ...H-Ni-H-Ni… chains in the structure with H atoms carrying a partial negative charge. Such hydrogen absorption accompanied by a formation of a covalent Ni-H bonding and causing an unusual behavior contracts to the conventionally observed bonding mechanism of hydrogen in metals as based on the metallic bonding frequently accompanied by a jumping diffusion movement of the inserted H atoms – in contrast to the directional Metal-Hydrogen bonding observed in the present work. At high applied pressures ScNiSnH$_{0.83}$ orthorhombic TiNiSi type hydride is formed with H atoms filling Sc$_3$Ni tetrahedra. Finally, this study shows that scandium closely resembles the behavior of the heavy rare earth metal holmium

Biological Earth observation with animal sensors

Space-based tracking technology using low-cost miniature tags is now delivering data on fine-scale animal movement at near-global scale. Linked with remotely sensed environmental data, this offers a biological lens on habitat integrity and connectivity for conservation and human health; a global network of animal sentinels of environmen-tal change

A simple model of an industrial catalytic cracking riser reactor

An ever-increasing complexity of the models of catalytic cracking (which is rarely justified by available monitoring data) makes “practical” modelling for industrial units challenging. In this work, we develop a simple numerical model for an industrial catalytic riser, the model with phenomenological parameters that are determined from an available monitoring data. The model is based on a four-lump reaction scheme (with coke being one of the lumps), with the kinetic parameters determined for an industrial reactor with zeolite-containing catalyst that is used for production of wet gases. The expression for the reaction rate reflects that reactions in gaseous phase occur in presence of solid (catalyst) phase. Hydrodynamics of non-isothermal reactive gas-solid mixtures is captured by a two-fluid model. Strong turbulence nature of the reactor flow makes possible to disregard the kinetic theory - based values for viscous, diffusion, and thermal conductivity coefficients (additionally reducing the number of needed empirical coefficients). The resultant model is applied for an in-depth analysis of the flow fields in the reactor, demonstrating a good agreement of the results with more sophisticated approaches. The model is also applied for calculation of optimal intakes of water vapour and catalyst

Interactive Visual Exploration of Teleconnections in Atmospheric Datasets

Traditional analyses of geoscientific data and their features require a lot of manual scripting to organize various tools and software libraries. We present a tool developed to cover the typical workflow of the task of analyzing dependencies between regions of the climate system. We propose an interactive visual analysis tool that uses a series of automated analysis steps combined with an interactive visual exploration of patterns in the data. We base our analysis on the statistical approach of strongest negative correlations for discovery of teleconnections. The interactive visual analysis process uses selecting, highlighting, and filtering in four coordinated views. The views represent teleconnectivity information within a teleconnectivity map and a teleconnectivity links list as well as correlation information within a correlation map and a projection view of the correlation space. We apply the tool to different datasets to demonstrate its capabilities for the analysis and comparison of correlation patterns

Measurement of magnetic noise in magnetoimpedance sensing element

A method for measurement of magnetic noise in magnetoimpedance sensing element is proposed. Glass-coated Co-based amorphous microwires with a slightly negative magnetostriction were used as the sensing element. The operation principle of the sensing element was based on the nonlinear off-diagonal magnetoimpedance, when field dependent higher harmonic components appeared in voltage in the pick-up coil wound around the microwire. The magnetic noise for the second harmonic in the pick-up coil voltage was studied. The dependences of the magnetic noise and the signal-to-noise ratio in the sensitive element on the current amplitude were analyzed. The noise performance of the second harmonic in the pick-up coil voltage was compared to that for a flux-gate sensing element

Development of a two-fluid hydrodynamic model for a riser reactor

We use ANSYS Fluent to examine the mixing of catalyst zeolite particles with petroleum feedstock and water vapor in a Fluid Catalytic Cracking (FCC) riser. We develop a two-fluid model for tracking catalyst particles and gas mixture in a riser, modelling the granular and gaseous phases as two interpenetrating continua. We analyze the hydrodynamic flows with the aim to single out the principal physical effects that determine the distribution of particles. We compare our results with a study that is based on a non-isothermal reactive model and demonstrate that our simplistic purely hydrodynamic model generates similar flow fields. The developed model is valuable for improvements of modern FCC risers. We apply the model for understanding the hydrodynamics of S-200 KT-1/1 industrial unit

Hydrogen induced structural phase transformation in ScNiSn-based intermetallic hydride characterized by experimental and computational studies

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