Spelling suggestions: "subject:"aphysical geography."" "subject:"2physical geography.""
621 |
The Development of a Gridded Weather Typing Classification SchemeLee, Cameron C. 13 June 2014 (has links)
<p> Since their development in the 1990s, gridded reanalysis data sets have proven quite useful for a broad range of synoptic climatological analyses, especially those utilizing a map pattern classification approach. However, their use in broad-scale, surface weather typing classifications and applications have not yet been explored. This research details the development of such a gridded weather typing classification (GWTC) scheme using North American Regional Reanalysis data for 1979-2010 for the continental United States. </p><p> Utilizing eight-times daily observations of temperature, dew point, pressure, cloud cover, u-wind and v-wind components, the GWTC categorizes the daily surface weather of 2,070 locations into one of 11 discrete weather types, nine core types and two transitional types, that remain consistent throughout the domain. Due to the use of an automated deseasonalized z-score initial typing procedure, the character of each type is both geographically and seasonally relative, allowing each core weather type to occur at every location, at any time of the year. Diagnostic statistics reveal a high degree of spatial cohesion among the weather types classified at neighboring locations, along with an effective partitioning of the climate variability of individual locations (via a Variability Skill Score metric) into these 11 weather types. Daily maps of the spatial distribution of GWTC weather types across the United States correspond well to traditional surface weather maps, and comparisons of the GWTC with the Spatial Synoptic Classification are also favorable. </p><p> While the potential future utility of the classification is expected to be primarily for the resultant calendars of daily weather types at specific locations, the automation of the methodology allows the classification to be easily repeatable, and therefore, easily transportable to other locations, atmospheric levels, and data sets (including output from gridded general circulation models). Further, the enhanced spatial resolution of the GWTC may also allow for new applications of surface weather typing classifications in mountainous and rural areas not well represented by airport weather stations.</p><p> </p>
|
622 |
Aeolian dust emission, transport and deposition in Western LibyaElatrash, Mokhtar Salem January 2004 (has links)
Of numerous aeolian studies around the world, few have been dedicated to dust trapping in the Saharan regions and none is known in Libya. This research aims to explore the extent of dust activities in the western part of Libya, the main factors that influence dust entrainment and deposition, the likely regional emission sources transporting aerosol to this part of the country and ultimately to establish base line information in space and time based on a study area larger than the size of the UK. Dust trapping was carried out at thirty sites on a monthly basis starting from the beginning June 2000 until the end of May 2001. A physical characterization of 274 aeolian sediments were based on grain size distribution analysis and the mineral composition was based on XRD testing of 24 dust samples taken from extreme locations near the Mediterranean Sea and about 800 km inland. An assessment of dust emissions within the area of study, the vertical deposition rates in relation to The Total Ozone Mapping Spectrometer (TOMS) data have been investigated. Moreover, an attempt identify potential Saharan dust emission sources that have impacted the study area has also been made utilizing TOMS data. The area of study has been divided into three regions northern, central and southern according to the dominant factors controlling mobilization of dust particles on the bed surface. This study concludes that deposition rates in the northern coastal region are largely dominated by human activities. Rates in the central region were strongly affected by topographic irregularities whereas in the south deposition rates were less affected by topography and anthropogenic activity. However, deposition rates and particle size distributions are strongly controlled by wind regimes and correlate with the average atmospheric temperatures. Local sediments seem to be strongly affected by saltating particles in most of the study area and no evidence of long range aerosol emission from western Libya was found. Nevertheless, fine dust (<10 gm) is wide spread in the local atmosphere, however it is more pronounced during late spring and summer. TOMS data and the prevailing wind directions reveal that the depressions of the Libyan Desert and the Bodele Depression in Chad were the main sources of aerosol transported over the study area during the highest months of emission, transport and deposition, July and April. It is hoped that this baseline information can pave the way for future studies on dust impacts on soil fertility, human health, desertification, climate change and the validation of present day computer models.
|
623 |
Strategic agenda building and change in the water industryFenton, Evelyn M. January 1996 (has links)
An investigation into the trajectory of river water quality as a strategic issue for the water industry was conducted within two water organisations. This research traced the profile of this issue on the agenda of the water authorities over twenty years and within the industry over a century. The aim was to gain insights into processes of strategic agenda building and organisational development and change, linking process to performance in the achievement of river quality. A contextualist theory of method was adopted in a comparative case study approach which sought to assess the performance of the two organisations in attaining improvements in river water quality during the time frame. The contextualist methodology necessitated examining the agenda building process from multiple levels and over time. To this end extensive archive research and 40 interviews were conducted.The influence of the wider social environment and the sector in the long term were found to be important in the formation of sector and organisational ideology which conditioned organisational developments. A structurationist approach demonstrated the key social structures and their properties implicated in the formation of organisational ideology and its change, as the water authorities were privatised. A process model of strategic agenda building was developed and extended, based on an earlier model by Dutton (1988). This emphasised the influence of multiple contexts, the role of organisational ideology, issue related activities and the actions of sponsors as important additions to the original model. Further, the use of structuration theory, underpinned by a Realist perspective, outlined a conception of agency based on the causal powers granted by the necessary relations of the organisational structure or ideology, and that agency was granted by organisational members' access to alternative structural systems outside the organisational context. This research concluded that the links between structure, process and performance are implicated in incremental and transformational change, and that the properties of structure were instrumental in the propensity for adaption and change. Finally, organisational processes should accurately reflect the rules of the system for change to work.
|
624 |
Microdebitage and the Archaeology of Rock Art: an experimental approachSusino, George James January 1999 (has links)
The search for a reliable and non-invasive technique for the dating of rock art has produced an array of different, localised, and limited techniques. This is one of them. Still in its experimental stage, the recognition of quartz microdebitage produced by the pecking of engravings is the aim of this project. This investigation aims to establish whether microdebitage from rock engravings can be distinguished from other sediments. Analysis of microdebitage from rock engraving experiments was used to determine the difference between experimental and naturally derived particles. This research discusses methodology, and applications for the recognition of quartz grain features, derived from experimental and natural material from Mutawintji National Park (Broken Hill, NSW, Australia) and the Sydney region (NSW Australia). A three-step process was devised for this research: What features occur on non-cultural quartz grains? What features occur on rock engraving quartz grains? Are they different? Can rock engraving quartz microdebitage be identified under natural conditions? Microdebitage from rock engravings was examined using optical and scanning electron microscopy to identify diagnostic attributes, with the objective of assessing the potential of microdebitage for spatial and temporal archaeological investigation. Characteristics of the quartz grains in the microdebitage were compared with quartz from differing environments. The observation of diagnostic features on quartz grains made it possible to discriminate between microdebitage from rock engravings and the natural soil background. This knowledge may be applied to excavated material from archaeological sites, for identifying episodes of rock engraving and other lithic activity in temporal relation to other evidence of cultural activity.
|
625 |
Territoire et agriculture en Valteline : géographie et groupes de relations /Torricelli, Gian Paolo. January 1990 (has links)
"Thèse présenté à la Faculté des sciences économiques et sociales de l'Université de Genève. Thèse n. 350." / Includes bibliographical references (p. 383-404).
|
626 |
Spatial and temporal dynamics of three East Antarctic outlet glaciers and their floating ice tonguesWuite, Jan. Unknown Date (has links)
Thesis (Ph.D.)--The Ohio State University, 2006. / (UMI)AAI3238159. Adviser: K. C. Jezek. Source: Dissertation Abstracts International, Volume: 67-10, Section: B, page: 5629.
|
627 |
A macroscale measurement and modeling approach to improve understanding of the hydrology of steep, forested hillslopes /Graham, Christopher Brian. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 151-158). Also available on the World Wide Web.
|
628 |
L'Extrême-Nord de MadagascarRossi, Georges. January 1900 (has links)
Abstract of Thesis (doctoral). / Three folded col. maps inserted. Includes bibliographical references (p. 427-435).
|
629 |
Development of a physical slope failure model /Dwyer, Todd Douglas. January 2004 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2004. / Typescript. Includes bibliographical references (leaves 109-110). Also available on the Internet.
|
630 |
La Vega de Granada Síntesis geográfica ...Ocaña Ocaña, María Carmen. January 1973 (has links)
Tesis (resumen)--Granada. / At head of title: Departamento de Geografía. Summary in English and French. Includes bibliographical references.
|
Page generated in 0.088 seconds