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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.
1

Measuring and building the South African weather service (SAWS) brand equity.

Mabusela, Xolile. January 2005 (has links)
The SAWS is interested in demonstrating the economic and social benefits of the products or services it provides to the public, industries and other organisations. It is also important for the organisation to carry out ongoing performance assessment of public and commercial weather services to ensure that these services are efficient and effectively meeting the public's and customer's needs and contribute to longer term commercial and societal objectives. Some other National Weather Services has developed "Service Charters" which detail their pledge of performance to the user communities, specifically, customers and the general public. These service charters provide a brief overview of the services provided, a commitment of performance against specific targets and a commitments to consult and identify a means by which the customers and the public may register their concern. As a result the service charters has become an important component of the Weather Services branding measurement strategy. The acceptance of the SAWS products or services by the public and other weather users depends on a number of factors. Scientific accuracy is just one of those factors. Also the health of the SAWS depends on the perceptions from full spectrum of weather users ranging from individual citizens, media, aviation, ... Ill marine, industry, government departments, construction companies, and insurance. These perceptions include those about requirements, accessibility, availability, accuracy, timelines, utility, comprehension, sufficient and packaging. The objective is to ultimately measure performance from the user perspective and identify user's needs. It is also to measure the acceptance of the services provided from such dimensions as expectations, understanding, importance, satisfaction, and utility. This study has been framed within the hypothesis that the SAWS brand associations are not strong, not favourable and not unique to create a positive brand. It has come critical to assess the level of customer awareness and familiarity with the SAWS brand so as to improve the dissemination mechanisms of the weather forecast information. Based on a literature review, two types of brand association are identified. One is product association including functional attribute association and non-functional attribute association. The other is organisational association including corporate ability association and corporate social responsibility association. It has been found that, the greater the number of the core brand association, the higher the brand equity. The feedback received on the questionnaire and interviews directed at awareness and familiarity with the SAWS brand indicated that, a need exists to educate the public and potential customers about the products and services of the SAWS. Of paramount important is the improvement of the SAWS dissemination mechanisms and partnerships with other scientific research organisations. This will enable the SAWS to reach a wide range of the public and weather users and to safeguard property and life of all South Africans. / Thesis (MBA)-University of KwaZulu-Natal, Durban, 2005.
2

The Verification of different model configurations of the Unified Atmospheric Model over South Africa

Mahlobo, Dawn Duduzile January 2013 (has links)
In 2006 a Numerical Weather Prediction (NWP) model known as the Unified Model (UM) from the United Kingdom Meteorological Office (UK Met Office) was installed at the South African Weather Service (SAWS). Since then it has been used operationally at SAWS, replacing the Eta model that was previously used. The research documented in this dissertation was inspired by the need to verify the performance of the UM in simulating and predicting weather over South Africa. To achieve this aim, three model configurations of the UM were compared against each other and against observations. Verification of rainfall as well as minimum and maximum temperature for the year 2008 was therefore done to achieve this. 2008 is the first year since installation, where all the configurations of the UM used in the study are present. For rainfall verification the model was subjectively verified using the eyeball verification for the entire domain of South Africa, followed by objective verification of categorical forecasts for rainfall regions grouped according to standardized monthly rainfall totals obtained by cluster analysis and finally objective verification using continuous variables for selected stations over South Africa. Minimum and maximum temperatures were subjectively verified using the eyeball verification for the entire domain of South Africa, followed by objective verification of continuous variables for selected stations over South Africa, grouped according to different heights above mean sea level (AMSL). Both the subjective and objective verification of the three model configurations of the UM (for both rainfall as well as the minimum and maximum temperatures) suggests that 12km UM simulation with DA gives better and reliable results than the 12km and 15km UM simulations without DA. It was further shown that although there was no significant difference between the model outputs from the 12km and the 15km UM without DA, the 15km UM simulation without DA, proved to me more reliable and accurate than the 12km UM simulation without DA in simulating minimum and maximum temperatures over South Africa, on the other hand the 12km UM simulation without DA is more reliable and accurate than the 15km UM simulation without DA in simulating rainfall over South Africa. / Dissertation (MSc)--University of Pretoria, 2013. / gm2014 / Geography, Geoinformatics and Meteorology / unrestricted
3

Comparing lightning polarity and cloud microphysical properties over regions of high ground flash density in South Africa

Simpson, Lee-ann January 2013 (has links)
Positive lightning flashes are known to be more intense and cause more damage than negative flashes, although positive flashes only occur about 10% of the time. This study expounds on cloud microphysical aspects of thunderstorms and investigates the occurrence, timing and location of ice particles within thunderstorms and correlates this to the occurrence of positive cloud-to-ground lightning events. Satellite data obtained from the Meteosat Second Generation (MSG) satellite, were used to: 1) depict Cloud Top Temperatures (CTT) by considering Infra Red (IR) radiation with a wave length of 10.8μm, 2) compare results from the CTT with the Brightness Temperature Difference (BTD) calculated by subtracting IR10.8μm from IR8.7μm, 3) after the cloud particle phase was determined from the abovementioned comparison, the sum of cloud-to-ground lightning strokes over a 1-hour period around the time of a reported lightning fatality was compared with cloud microphysical properties and then 4) these results were further compared with the lightning polarity obtained from the South African Weather Service (SAWS) Lightning Detection Network (LDN) data set. Four case studies were identified to investigate from the many available case study dates. These four cases occurred on 3 separate days namely: 1)22 November 2007, iii 2) 10 February 2009 and 3) 29 October 2009. There were two fatal events reported on 22 November 2007 and therefore two cases studies were compiled for this one date. On 10 February 2009 over 250 insurance damage claims were honoured but no fatality was reported. The three case studies mentioned above were classified as primary case studies. The 29 October 2009 case was classified as a secondary, more generalized case which was chosen in order to test whether the results gained from the first three cases were indeed noteworthy. Results gathered from two of the three primary case studies showed that the fatalities occurred when the most intense part of the thunderstorm was to the east of the location where the lightning struck the victims, although actual storm properties were not considered as being particularly severe. The lightning data for the primary case studies showed that the percentage of cloud-to-ground lightning was within 10% of the total number of strokes recorded for 22 November 2007, and above 10% for 10 February 2009. In the one secondary case study of 29 October 2009 the percentage of positive lightning was only between 2% and 4% of the total number of strokes recorded, which was significantly lower than in the three primary cases. A significant difference in cloud microphysics between the primary and secondary cases was the possible occurrence of super-cooled liquid water found in Cumulonimbus (CB) clouds in the secondary case. This could have been a determining factor for the difference in percentage of positive lightning between the primary and secondary case studies. / Dissertation (MSc)--University of Pretoria, 2013. / gm2014 / Geography, Geoinformatics and Meteorology / unrestricted
4

Verification of South African Weather Service operational seasonal forecasts

Moatshe, Peggy Seanokeng 11 August 2009 (has links)
The South African Weather Service rainfall seasonal forecasts are verified for the period of January-February-March to October-November-December 1998-2004. These forecasts are compiled using different models from different institutions. Probability seasonal forecasts can be evaluated using different skill measures, but in this study the Ranked Probability Skill Score (RPSS), Reliability Diagram (RD) and Relative Operating Characteristics (ROC) are used. The RPSS is presented in the form of maps whereas the RD and ROC are analyses are presented in the form of graphs. The aim of the study is to present skill estimates of operational seasonal forecasts issued at South African Weather Service A limited number of forecasts show positive RPSS value throughout the validation period. From RD and ROC analysis, there is no skill in predicting the normal category as compared to below-normal and above-normal categories. Notwithstanding, the frequency diagrams show that the normal category was often given a large weight in the operational forecasts. The value of verifying seasonal forecast accuracy from the user’s perspective is important. The understanding of seasonal forecast performance helps decision makers to determine when and how to respond to expected climate anomalies. Therefore the frequent update of the seasonal forecast verification is important in order to help Users make better decisions. Copyright / Dissertation (MSc)--University of Pretoria, 2008. / Geography, Geoinformatics and Meteorology / Unrestricted
5

Volatile organic compounds(VOC's) analysis from Cape Town haze ll study

Chiloane, Kgaugelo Euphinia 09 November 2006 (has links)
Student Number: 9503012G Master of Science. School of Geography, Archaeology and Environmental Studies / A brown haze which builds-up over Cape Town under calm and cold weather conditions causes public concern. The brown haze is thought to be due to the gaseous and particulate emissions from the city, industries, traffic and townships in the Cape Town region. Volatile organic carbon (VOCs) compounds are an important component of the haze layer particularly because of their reactivity. VOCs play an important role in the carbon budget and radiation balance, regional oxidant balance, and in the distribution of ozone and other reactive gases, both at the regional and global scale. In this study the variation in ambient VOC concentrations during brown and non-brown haze days over Cape Town during July and August 2003 were characterised. Ambient air samples were collected in evacuated stainless steel canistes from the South African Weather Service (SAWS) research aircraft (Aerocommander, ZS-JRB) and later analysed by gas chromotography equipped with a flame ionisation detector (GC-FID). Benzene, toluene, ethylbenzene and xylene (BTEX) were the specific VOCs targeted for this study. Comparable meteorology data was also collected to determine the effects of wind field and atmospheric stability on BTEX concentrations.

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