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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
221

Ancient weather signs : texts, science and tradition

Beardmore, Michael Ian January 2013 (has links)
This thesis offers a new contextualisation of weather signs, naturally occurring terrestrial indicators of weather change (from, for example, animals, plants and atmospheric phenomena), in antiquity. It asks how the utility of this method of prediction was perceived and presented in ancient sources and studies the range of answers given across almost eight hundred years of Greek and Roman civilisation. The presentation of weather signs is compared throughout to that of another predictive method, astrometeorology, which uses the movement of the stars as markers of approaching weather. The first chapter deals with the presentation and discussion of weather signs in a range of Greek texts. It sees hesitant trust being placed in weather signs, lists of which were constructed so as to be underpinned by astronomical knowledge. The second chapter assesses how these Greek lists were received and assimilated into Roman intellectual discourse by looking to the strikingly similar practice of divining by portents. This lays the foundations for the final chapter, which describes and explains the Roman treatment of weather signs. Here, the perceived utility of weather signs can be seen to reduce rapidly as the cultural significance of astronomy reaches new heights. This thesis provides new readings and interpretations of a range of weather-based passages and texts, from the Pseudo-Theophrastan De Signis, to Lucan's Pharsalia, to Pliny's Natural History, many of which have previously been greatly understudied or oversimplified. It allows us to understand the social and scientific place of weather prediction in the ancient world and therefore how abstract and elaborate ideas and theories filtered in to the seemingly commonplace and everyday. I argue that between the 7th century BC and the end of the 1st century AD, the treatment of weather signs changes from being framed in fundamentally practical terms to one in which practical considerations were negligible or absent. As this occurred, astrometeorology comes to be seen as the only predictive method worthy of detailed attention. These two processes, I suggest, were linked.
222

Applying a credit default swap valuation approach to price South African weather derivatives / Amelia Nadine Holemans

Holemans, Amelia Nadine January 2010 (has links)
Most farmers in South Africa use standard insurance to protect their crops against natural disasters such as hail or strong winds. However, no South African insurance contracts exist to compensate for too much or too little rain (although floods are covered), or which will pay out if temperatures were too high or too low for a certain period of time for the relevant crop. Weather derivatives - which farmers may employ to ensure crops against adverse temperatures - do exist, but these are mostly available in foreign markets in the form of Heating Degree Days contracts and Cooling Degree Day contracts and are used chiefly by energy companies. Some South African over-the-counter weather derivatives are available, but trading in these is rare and seldom used. The goal of this dissertation is to establish a pricing equation for weather derivatives specifically for use in the South African market. This equation will be derived using a similar methodology to that employed for credit default swaps. The premium derived will be designed to compensate grape farmers from losses arising from two different climatic outcomes - in this case temperature and precipitation. These derivatives will be region and crop specific and the formulation will be sufficiently flexible as to allow for further climatic possibilities (which may be added at a later stage). These weather derivative premiums will then be compared to standard crop insurance to establish economic viability of the products and recommendations will be made regarding their usage. The possibility of the simultaneous use of these derivatives and standard crop insurance for optimal crop coverage will also be explored and discussed. / Thesis (M.Com. (Risk management))--North-West University, Potchefstroom Campus, 2011.
223

Applying a credit default swap valuation approach to price South African weather derivatives / Amelia Nadine Holemans

Holemans, Amelia Nadine January 2010 (has links)
Most farmers in South Africa use standard insurance to protect their crops against natural disasters such as hail or strong winds. However, no South African insurance contracts exist to compensate for too much or too little rain (although floods are covered), or which will pay out if temperatures were too high or too low for a certain period of time for the relevant crop. Weather derivatives - which farmers may employ to ensure crops against adverse temperatures - do exist, but these are mostly available in foreign markets in the form of Heating Degree Days contracts and Cooling Degree Day contracts and are used chiefly by energy companies. Some South African over-the-counter weather derivatives are available, but trading in these is rare and seldom used. The goal of this dissertation is to establish a pricing equation for weather derivatives specifically for use in the South African market. This equation will be derived using a similar methodology to that employed for credit default swaps. The premium derived will be designed to compensate grape farmers from losses arising from two different climatic outcomes - in this case temperature and precipitation. These derivatives will be region and crop specific and the formulation will be sufficiently flexible as to allow for further climatic possibilities (which may be added at a later stage). These weather derivative premiums will then be compared to standard crop insurance to establish economic viability of the products and recommendations will be made regarding their usage. The possibility of the simultaneous use of these derivatives and standard crop insurance for optimal crop coverage will also be explored and discussed. / Thesis (M.Com. (Risk management))--North-West University, Potchefstroom Campus, 2011.
224

A probabilistic impact-focussed early warning system for flash floods in support of disaster management in South Africa

Poolman, Eugene Rene January 2015 (has links)
The development of the Severe Weather Impact Forecasting System (SWIFS) for flash flood hazards in South Africa is described in this thesis. Impact forecasting addresses the need to move from forecasting weather conditions to forecasting the consequential impact of these conditions on people and their livelihoods. SWIFS aims to guide disaster managers to take early action to minimise the adverse effects of flash floods focussing on hotspots where the largest impact is expected. The first component of SWIFS produced an 18-hour probabilistic outlook of potential occurrence of flash floods. This required the development of an ensemble forecast system of rainfall for small river basins (the forecasting model component), based on the rainfall forecast of a deterministic numerical weather prediction model, to provide an 18-hour lead-time, taking into account forecast uncertainty. The second component of SWIFS covered the event specific societal and structural impacts of these potential flash floods, based on the interaction of the potential occurrence of flash floods with the generalised vulnerability to flash floods of the affected region (the impact model component). The impact model required an investigation into the concepts of regional vulnerability to flash floods, and the development of relevant descriptive and mathematical definitions in the context of impact forecasting. The definition developed in the study links impact forecasting to the likelihood and magnitude of adverse impacts to communities under threat, based on their vulnerability and due to an imminent severe weather hazard. Case studies provided evidence that the concept of SWIFS can produce useful information to disaster managers to identify areas most likely to be adversely affected in advance of a hazardous event and to decide on appropriate distribution of their resources between the various hotspots where the largest impacts would be. SWIFS contributes to the current international research on short-term impact forecasting by focussing on forecasting the impacts of flash floods in a developing country with its limited spatial vulnerability information. It provides user-oriented information in support of disaster manager decision-making through additional lead-time of the potential of flash floods, and the likely impact of the flooding. The study provides a firm basis for future enhancement of SWIFS to other severe weather hazards in South Africa. / Thesis (PhD)--University of Pretoria, 2015. / gm2015 / Geography, Geoinformatics and Meteorology / PhD / Unrestricted
225

A quantitative measure of the thermal insulation value of certain items of men's wear

Franz, Delores Frances. January 1966 (has links)
Call number: LD2668 .T4 1966 F837 / Master of Science
226

Arizona Watershed Stewardship Guide: Arizona Weather & Climate

Emanuel, Robert, Garfin, Gregg January 2005 (has links)
14 pp. / Arizona Watershed Stewardship Guide: Geologic Processes Arizona Watershed Stewardship Guide: Watershed Ecology Arizona Watershed Stewardship Guide: Watershed Hydrology Arizona Watershed Stewardship Guide: Watershed Soils / Arizona Watershed Stewardship Guide was created to help individuals and groups build a mutual foundation of basic knowledge about watersheds in Arizona. It is intended to help Arizonans understand and be good stewards of their watersheds. This guide was designed to compliment the mission of the Arizona Master Watershed Steward Program to educate and train citizens across the state to serve as volunteers in the monitoring, restoration, conservation, and protection of their water and watersheds. This guide consists of 10 self-contained modules which teach one or more important aspects of watershed science or management to a public adult audience.
227

Arizona and the North American Monsoon System

Crimmins, Michael 09 1900 (has links)
8 pp. / This publication provides an depth look at the North American Monsoon system and its impact on summer weather in Arizona.
228

On the relationship between Eurasian snow cover, Asian summer rainfall, atmospheric circulation and sea surface temperature

Choi, Byoung-Choel January 2000 (has links)
No description available.
229

Accuracy of Atlantic and Eastern North Pacific tropical cyclone intensity guidance

Lambert, Tara Denise Barton 09 1900 (has links)
Five statistical and dynamical tropical cyclone intensity guidance techniques available at the National Hurricane Center during the 2003 and 2004 Atlantic and Eastern North Pacific seasons were evaluated within three intensity phases: (I) formation; (II early intensification; and (III) decay. During the formation phase, the Decay Statistical Hurricane Intensity Prediction (DSHIPS) technique was the best technique in both basins. When the forecast errors during formation exceed +/- 10 kt, the statistical techniques tend to over-forecast and the dynamical models tend to under-forecast. Whereas DSHIPS was also the best technique in the Atlantic during the early intensification stage, the Geophysical Fluid Dynamics Laboratory model was the best in the Eastern North Pacific. All techniques under-forecast periods of rapid intensification and the peak intensity, and have an overall poor performance during decay-reintensification cycles in both basins. Whereas the DSHIPS was the best technique in the Atlantic during decay, none of the techniques excelled during the decay phase in the eastern North Pacific. All techniques tend to decay the tropical cyclones in both basins too slowly, except that the DSHIPS performed well (13 of 15) during rapid decay events in the Atlantic. Similar error characteristics had been found in the western North Pacific.
230

Effects of noise, temperature, humidity, motion and light on the sleep patterns of the Crew of HSV-2 SWIFT

Archibald, Keith. 09 1900 (has links)
Human Systems Integration Report / This study examined the effects of noise, temperature, humidity, motion and light on the sleep patterns of the crew of the HSV-2 SWIFT during Gulf of Mexico Exercise (GOMEX) 05-1. HSV-2 SWIFT was chosen for this study to examine crew sleep on an unconventional hull type manned with a small crew. Noise dosimeters, temperature and humidity monitors, actiwatches and questionnaires were used to quantify the data. With the exception of light, the independent variables did not have significant effect upon participant sleep. This is likely due to the limited range of the independent variables and the small number of participants in this study. There were two findings in this study; the relationship between the demographic variable sea time and participant sleep and the relationship between the independent variable light and participant sleep. Due to the limitations in the current study, it is recommended that further studies be conducted in more extreme operational environments. Additionally, studies such as the one discussed in this thesis, should be completed on different platforms to determine the differences in environmental factors that affect sleep between hull types so that the results can be applied to future vessel design.

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