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Spatial and Temporal Characteristics of Precipitation Variability and Drought Patterns in the Eastern Mediterranean
Full text linkAs precipitation is a very important parameter of climate and hydrology, exploring spatial and temporal distribution and variation of this variable can give an idea about climate conditions and water resources in the future. Therefore accurate mapping of the temporal and spatial distributions of precipitation is important for many applications in hydrology, climatology, agronomy, ecology and other environmental sciences. In this thesis, spatiotemporal distributions and variations of total annual, seasonal and monthly precipitation of the Eastern Mediterranean (EM) are analysed. The Eastern Mediterranean is one of the most prominent hot spot of climate change in the world further; extreme climatic events such as drought are expected to become more frequent and intense in this region.
Main data source is instrumental data of monthly and daily precipitation at 103 and 70 meteorological stations, respectively.
Spatial coherence analysis, coefficient of variation (CV), rainfall seasonality index (SI), incomplete gamma distribution and precipitation concentration index (PCI) are applied to evaluate the seasonality and variability of annual, seasonal and monthly precipitation amounts and their distribution. Daily precipitation concentration index (CI) is used as an important index for specifying daily rainfall characteristics. Additionally, rainfall entropy is also calculated for monthly and daily data for finding the most suitable probability distribution under the available information. High to moderate irregularity and rainfall concentration are the two very characteristic features of rainfall in the EM. Highest values of daily CI are detected in the southern parts of the EM. Distribution of annual precipitation CI trends indicate a statistically significant increase in the northern and northwestern regions of the EM.
Four meteorological drought indices (DIs) are calculated at monthly time scale, the Standardized Precipitation Index (SPI), the Modified China Z Index (MCZI), the Statistical Z -scores and the Rainfall Decile based Drought Index (DI) while the Effective Drought Index (EDI) is calculated at daily time scale. All selected DIs with multiple time steps are applied to compute the severity for five time steps of 3, 6, 9, 12 and 24-month, and compared with each other and EDI.
The most significant factor affecting the spatial accuracy of drought indices is seasonality. Study of DIs shows that the DIs are highly correlated at same time steps and can alternatively be used and the DIs computed for 6 and 9-month time step are best correlated with each other. SPI and MCZI are more consistent in detecting droughts for different time steps. EDI is found to be best correlated with other DIs when considering all time steps. The investigation shows that the use of an appropriate time step is as important as the type of DI used to identify drought severities.
Principal Component Analysis (PCA) is employed and reveals the main modes and spatiotemporal variability of seasonal and annual precipitation and droughts over the EM. The preliminary analysis indicated tendencies towards a drier climate due to a statistically significant decrease in annual precipitation over the EM.
The analysis of indicators of extreme events reveals a much more complex transformation of the climatic pattern with strong regional and seasonal variation.
The results demonstrated that an extreme wet spells in the EM will shorten in all seasons, except autumn. Precipitation extremes are projected to become more pronounced in the northern parts of the EM than in southern ones and tend to be more significant during autumn. Extreme and heavy precipitation events showed a statistically significant decrease in whole parts of the
EM and in the southern ones, respectively with a significant decreasing in total precipitation amount. A significant increase in daily intense precipitation events in the northern parts of the EM. In addition, climate extreme indices recommended by the joint World Meteorological Organization (CCL/CLIVAR/JCOMM) Expert Team on Climate Change Detection and Indices (ETCCDI) are also calculated for daily precipitation data.
Finally, Mann- Kendall test, cumulative sum chart (CUSUM), regime shift index (RSI) calculated by a sequential algorithm are applied for detecting the shifts in the means of seasonal and annual precipitations. Mann-Kendall test and the linear slopes of trends are calculated using Sen’s slope estimator to determine the trend magnitude for SPI, CI, extreme precipitation indices, dry and drought periods. The highest decreasing of rainfall amounts is found in spring and winter and these seasons are the overall driving factor of trends in annual precipitation. Overall results of the trend analysis on the reconstructed shows that over last 52 years the drought events are more sever and frequent after 1990s over the EM which reflects negative effects on socio- economic sectors as well as water resources in this region. The findings of this study could be used or extended in further studies in the future to gain insights regarding the precipitation variability, drought patterns and extreme events over the domain of the EM.La precipitación es una variable muy importante del clima y la hidrología. La exploración de su distribución espacial y temporal y su variación puede dar una idea acerca de las condiciones del clima y los recursos hídricos en un futuro. Por lo tanto, el mapeo amento? Preciso de la distribución temporal y espacial resulta importante para muchas aplicaciones ya sea en hidrología, climatología, agronomía, ecología, y otras ciencias ambientales.
En esta tesis, se analizan las distribuciones espacio-temporales y variaciones de la precipitación total anual, estacional y mensual en el Mediterráneo Oriental (MO).
El Mediterráneo Oriental es uno de los puntos calientes más prominentes al cambio climático por lo que espera que los eventos climáticos extremos, como las sequías, sean más frecuentes e intensas en esta región.
La principal fuente de datos es instrumental, de estaciones meteorológicas. Con un total de 103 a escala mensual y 70 a escala diaria.
El análisis espacial de coherencia, el coeficiente de variación (CV), el índice de estacionalidad y precipitaciones (SI), la distribución gamma incompleta y el índice de concentración de la precipitación (PCI), se aplican para evaluar la estacionalidad y la variabilidad de las cantidades de precipitación anual, estacional y mensual y su distribución. El índice de concentración de la precipitación diaria (CI) se utiliza como índice imprescindible para la especificación de las características diarias de lluvia. Además, la entropía de las precipitaciones también se calcula para los datos mensuales y diarios con el fin de encontrar la distribución de probabilidad más adecuada de la información disponible. Una irregularidad moderada y la concentración de las precipitaciones son los dos rasgos más característicos de las precipitaciones en la EM. Los valores más altos de CI diario se detectan en las partes meridionales de la EM. La distribución de las tendencias anuales de (CI precipitación) indican un aumento estadísticamente significativo en las regiones del norte y noroeste de la EM.
Cuatro índices de sequía meteorológica (DIs) se calculan a escala de tiempo mensual, el Índice de Precipitación Estandarizada (SPI), la modificación de China Índice Z (MCZI), los -scores Z estadísticos y el Índice de Sequía basada precipitaciones débil (DI), mientras que la sequía Efectiva Índice (EDI) se calcula en la escala de tiempo diario. Todos los DIs seleccionados con múltiples pasos de tiempo se aplican para calcular la gravedad durante cinco pasos de tiempo de 3, 6, 9, 12 y 24 meses, y se compararon entre sí y con EDI. El factor más importante que afecta a la precisión espacial de índices de sequía es la estacionalidad. El estudio de DIs muestra que los DI están altamente correlacionados en mismos pasos de tiempo y de forma alternativa se pueden utilizar, y los DI calculados para los pasos de tiempo de 6 y 9 meses son los más correlacionados entre sí. SPI y MCZI son más consistentes en la detección de las sequías para los diferentes pasos de tiempo. El EDI tiene la mejor correlación con otros DIS en diferentes pasos de tiempo.
La investigación muestra que el uso de un paso de tiempo apropiado es tan importante como el tipo de DIs utilizado para identificar severidades de sequía.
Los análisis de los Componentes Principales (PCA) se emplean y revelan los principales modos de la variabilidad espacio-temporal de la precipitación estacional, anual y también los episodios de
las sequías del MO. El análisis preliminar indica tendencias hacia un clima más seco debido a una disminución estadísticamente significativa en la precipitación anual durante el MO.
El análisis de los indicadores de los fenómenos extremos revela una transformación mucho más compleja de la pauta climática con fuerte variación regional y estacional.
Los resultados demostraron que episodios de lluvia extrema en el EM se acortarán en todas las estaciones, excepto otoño. Las precipitaciones extremas se proyectan a ser más pronunciadas en la parte norte de la MO que en las del sur, y tienden a ser más significativas en el otoño. Eventos extremos de precipitación mostraron una disminución estadísticamente significativa en partes enteras de la EM, y en las del sur, respectivamente, con una significativa disminución en la cantidad total de precipitación y un aumento significativo de las precipitaciones intensas diarias en la parte norte de la EM. Además, los índices de extremos climáticos recomendados por la Organización Meteorológica Mundial (CCL / CLIVAR / CMOMM), con un equipo de expertos sobre detección del cambio climático e índices (ETCCDI), también se calculan para los datos de precipitación diaria.
Por último, la prueba de Mann-Kendall, carta suma acumulativa (CUSUM), el índice de cambio de régimen (RSI), calculado mediante un algoritmo secuencial fueron aplicadas para detectar los cambios en el medio de las precipitaciones estacionales y anuales. La prueba de Mann-Kendall y las pistas lineales de las tendencias se calculan utilizando la pendiente estimadora de Sen para determinar la magnitud tendencia de SPI, CI, los índices de precipitación extrema, los períodos secos y sequías. La mayor disminución de las cantidades de lluvia se encuentra en la primavera e invierno. Estas estaciones son el factor de conducción general de las tendencias de la precipitación anual. Y los resultados generales del análisis de las tendencias en los programas reconstruidos indican que durante los últimos 52 años las sequías son más frecuentes después el año 1990 sobre el MO, los cuales reflejan los efectos negativos sobre los sectores socioeconómicos, así como los recursos hídricos en esta región. Los hallazgos de este estudio podrían utilizarse o ampliarse en otros estudios en el futuro para obtener información con respecto a la variabilidad de la precipitación, patrones de sequía y fenómenos extremos sobre el dominio del MO
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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