Everyday parables: learnings from life

Reviewed Book: Taylor, James. Everyday parables: learnings from life. Winfield, BC: Wood Lake Bks, 1995

Praying the catechism

Reviewed Book: Johnson, Donald W. Praying the catechism. Winnipeg: Evangelical Lutheran Church in Canada, 1995

Analysis of a Research-Based Show Choir Competition Adjudication Rubric: Reliability and User Perceptions

A weighted rubric, created in a prior pilot study, used for adjudicating nine show choir competitions was statistically analyzed to determine reliability. A survey and ten interviews with adjudicators were examined to ascertain user perceptions. Results from an intraclass correlation coefficient indicate that the Tyson Rubric has excellent inter-rater reliability. Survey respondents indicated that the Tyson Rubric provides a step towards standardization in the genre of show choir, though improvements were suggested. Interviews were transcribed and coded, revealing themes of bias in show choir adjudication, the need for standardization in the genre, and the need for improved adjudication training. The study suggests that further research is needed to determine better practices in show choir adjudication due to a lack of empirical research in the genre

Preface "Nonlinear processes in oceanic and atmospheric flows"

Nonlinear phenomena are essential ingredients in many oceanic and atmospheric processes, and successful understanding of them benefits from multidisciplinary collaboration between oceanographers, meteorologists, physicists and mathematicians. The present Special Issue on ``Nonlinear Processes in Oceanic and Atmospheric Flows'' contains selected contributions from attendants to the workshop which, in the above spirit, was held in Castro Urdiales, Spain, in July 2008. Here we summarize the Special Issue contributions, which include papers on the characterization of ocean transport in the Lagrangian and in the Eulerian frameworks, generation and variability of jets and waves, interactions of fluid flow with plankton dynamics or heavy drops, scaling in meteorological fields, and statistical properties of El Ni\~no Southern Oscillation.Comment: This is the introductory article to a Special Issue on "Nonlinear Processes in Oceanic and Atmospheric Flows'', published in the journal Nonlinear Processes in Geophysics, where the different contributions are summarized. The Special Issue itself is freely available from http://www.nonlin-processes-geophys.net/special_issue103.htm

Comparison between Eulerian diagnostics and finite-size Lyapunov exponents computed from altimetry in the Algerian basin

Transport and mixing properties of surface currents can be detected from altimetric data by both Eulerian and Lagrangian diagnostics. In contrast with Eulerian diagnostics, Lagrangian tools like the local Lyapunov exponents have the advantage of exploiting both spatial and temporal variability of the velocity field and are in principle able to unveil subgrid filaments generated by chaotic stirring. However, one may wonder whether this theoretical advantage is of practical interest in real-data, mesoscale and submesoscale analysis, because of the uncertainties and resolution of altimetric products, and the non-passive nature of biogeochemical tracers. Here we compare the ability of standard Eulerian diagnostics and the finite-size Lyapunov exponent in detecting instantaneaous and climatological transport and mixing properties. By comparing with sea-surface temperature patterns, we find that the two diagnostics provide similar results for slowly evolving eddies like the first Alboran gyre. However, the Lyapunov exponent is also able to predict the (sub-)mesoscale filamentary process occuring along the Algerian current and above the Balearic Abyssal Plain. Such filaments are also observed, with some mismatch, in sea-surface temperature patterns. Climatologies of Lyapunov exponents do not show any compact relation with other Eulerian diagnostics, unveiling a different structure even at the basin scale. We conclude that filamentation dynamics can be detected by reprocessing available altimetric data with Lagrangian tools, giving insight into (sub-)mesoscale stirring processes relevant to tracer observations and complementing traditional Eulerian diagnostics

Vortices of the Mediterranean Sea: An Altimetric Perspective

17 pages, 12 figures, 2 tablesThe presence of coherent vortices makes observed mesoscale fields of the ocean resemble two-dimensional turbulence. Using this analogy, a common definition of a coherent structure has been used to study the statistical properties of Mediterranean Sea vortices observed by satellite altimeters over a 7-yr period. A vortex has been defined as the simply connected region with values of the Okubo–Weiss parameter W < −0.2σW, where σW is the spatial standard deviation of W, and the same sign of vorticity. This definition is shown to be appropriate to detect and characterize, statistically, properties such as size, mean kinetic energy, and amplitude of vortices in the Mediterranean basin from sea level anomaly maps corresponding to the period from October 1992 to October 1999. The distribution of such properties for the Mediterranean vortices suggests a heuristic criterion to extract and select very coherent and long-lived vortices from the whole set of structures identified in altimetric maps. Such coherent vortices appear to be selected for amplitudes greater than 2σW, where the amplitude has been defined in terms of the Okubo–Weiss parameter rather than vorticity, and strongly correspond to those reported from observations with independent data. Systematic locating and tracking of such vortices provide, for the first time, a general picture of their preferential paths in the Mediterranean basin, which are characterized by complex but rather well defined patternsThis is a contribution to the IMAGEN project funded by the Spanish R+D Plan (REN2001-0802-C02-02) and MERSEA project funded by the European Union 6th Framework Program (AIP3-CT-2003-502885). Jordi Isern-Fontanet has been partially supported by contracts from IMAGEN and MERSEA projects. Altimetric maps for the period analyzed were elaborated and provided by CLS (Toulouse, France) under contract of the MATER project funded by the European Union MAST Program (MAS3-CT96-0051)Peer reviewe

Image registration techniques with multiresolution analysis in satellite oceanography

En aquest article es fa una descripció dels procediments realitzats per enregistrar dues imatges geomètricament, de forma automàtica, si es pren la primera com a imatge de referència. Es comparen els resultats obtinguts mitjançant tres mètodes. El primer mètode és el d’enregistrament clàssic en domini espacial maximitzant la correlació creuada (MCC)[1]. El segon mètode es basa en aplicar l’enregistrament MCC conjuntament amb un anàlisi multiescala a partir de transformades wavelet [2]. El tercer mètode és una variant de l’anterior que es situa a mig camí dels dos. Per cada un dels mètodes s’obté una estimació dels coeficients de la transformació que relaciona les dues imatges. A continuació es transforma per cada cas la segona imatge i es georeferencia respecte la primera. I per acabar es proposen unes mesures quantitatives que permeten discutir i comparar els resultats obtinguts amb cada mètode.In this paper we present processing techniques for automated image-to-image geometrical registration. One reference image is used to register the working image. Three methods are used. The first method is the classical image registration method using the maximum cross-correlation (MCC) in the spatial domain [1]. The second method is based on MCC and multiscale analysis through wavelet multiresolution techniques [2]. The third one is a fusion of the two previous methods. For each technique the transformation coefficients relating both images are estimated. Finally, the second image is transformed and georeferenced to the first one. In the conclusion, a proposal of quantitative parameters leads to a final discussion on the results.En este artículo se describen los procedimientos realizados para registrar geométricamente dos imágenes de forma automática si se toma la primera como imagen de referencia. Se comparan los resultados obtenidos mediante tres métodos. El primero es el método clásico para registrar dos imágenes en el dominio espacial maximizando la correlación cruzada (MCC) [1]. En el segundo se trata de aplicar de forma conjunta técnicas de análisis multiescalar, basadas en las transformaciones wavelet y el método MCC [2]. El tercero es una variación del segundo situada a medio camino de los dos métodos anteriores. Para cada método se obtiene una estimación de los coeficientes de la transformación que relaciona las dos imágenes. A continuación, se transforma la segunda imagen que se georreferencia respecto a la primera para cada caso. Para finalizar se proponen unas medidas cuantitativas que nos permiten discutir y comparar los resultados obtenidos en cada uno de los método

Multifractal Method for the Instantaneous Evaluation of the Stream Function in Geophysical Flows

4 pages, 3 figuresMultifractal or multiaffine analysis is a promising new branch of methods in nonlinear physics for the study of turbulent flows and turbulentlike systems. In this Letter we present a new method based on the multifractal singularity extraction technique, the maximum singular stream-function method (MSSM), which provides a first order approximation to the stream function from experimental data in 2D turbulent systems. The essence of MSSM relies in relating statistical properties associated with the energy cascade in flows with geometrical properties. MSSM is a valuable tool to process sparse collections of data and to obtain instant estimates of the velocity field. We show an application of MSSM to oceanography as a way to obtain the current field from sea surface temperature satellite images; we validate the result with independent dynamical information obtained from sea level measurements. © 2005 The American Physical SocietyThis is a contribution to IMAGEN (Spanish R+D Plan: REN2001-0802-C02-02) and MERSEA projects (EU AIP3-CT-2003-502885). A. Turiel is contracted under the Ramon y Cajal program by the Spanish Ministry of Education. J. Isern-Fontanet is funded by the IMAGEN and MERSEA projectsPeer Reviewe