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A wide area assessment of forecast changes in wintertime synoptic conditions over western North America is combined with a meso-scale alpine hydrometeorology model to evaluate the joint impact(s) of forecast climate change on snowpack conditions in an alpine watershed in the southern Canadian Rockies. The synoptic analysis was used to generate long-term climate time series scenarios using the CCCma CGCM1. An alpine hydrometerology model is used to predict changes in wintertime precipitation at the watershed scale. A mass balance snow model is utilized to predict the overall snow accumulation throughout a watershed. A vapour transfer model has been incorporated in the snow model to estimate snow volumes more accurately. The synoptic analysis and GCM output forecasts a modest increase in both winter precipitation and temperatures in the study area, resulting in a decline of winter snow accumulations, and hence an expected decline in spring runoff. / ix, 87 leaves : ill. ; 28 cm.

The causes of increasing outbreaks of Acanthaster planci on the Great Barrier Reef have been a point of hot debate in recent years. It is unknown whether the increased success is due to nutrient runoff, salinity levels, or a decrease in predation, among other possibilities. In this paper I argue that the primary influence on outbreak status is sea surface temperature. From existing literature, I demonstrate that sea surface temperature in the Great Barrier Reef has increased by 0.4°C per year over the past three decades. I attempt to tie this increase with an increase in frequency of A. planci outbreaks on a selection of reefs throughout the Great Barrier Reef region. Due to the development of A. planci, specifically the fact that it takes them between 2 and 3 years to reach full maturity, I examined the potential relationship between an outbreak and the sea surface temperature 1 and 2 years before the event. Through my exploration of the data and my subsequent data analysis, it is clear that there are no statistically significant results when comparing the three classifications of outbreak (active, incipient, and recovering) and not outbreaking populations with temperature at each of the three time relationships. However, when I considered the three stages of outbreak to be “affected” and those not outbreaking to be “unaffected”, I found a statistically significant relationship. This finding has important implications when looking at the temperature changes that have been predicted for the Great Barrier Reef region due to global climate change. If the water temperature continues to increase, A. planci will more often be living within their optimal temperature range and will be more successful, continue to have major outbreaks that devastate the reef ecosystem, and eventually destroy it all together.

Global warming and increasing atmospheric nitrogen deposition are ranked as second and third most important global drivers of biodiversity loss. Widespread species losses have deep implications for the functioning of ecosystems, the delivery of essential ecosystem services and their resilience to future environmental perturbations. There is growing recognition that interactions between species play a crucial role in determining the response of ecosystems to global environmental changes. Moreover, evidence of synergistic effects between global change drivers has prompted numerous calls to integrate multiple drivers in ecological research. Nevertheless, empirical studies assessing the impacts of temperature and nitrogen on communities at multiple trophic levels are largely absent. This thesis explores the effects of temperature and nitrogen on a tri-trophic system comprising plants, herbivores and natural enemies. The first chapter shows impacts of the drivers on the composition and phenology of an herbivore community. The second chapter highlights changes in biomass under the treatments at three trophic levels. The third chapter explores, for the first time, the impacts of temperature and nitrogen on quantitative food webs. Finally, the last data chapter uses body size as an important species trait to gain insights on the mechanisms causing shifts in food web structure. The key findings of this thesis were i) trophic interactions largely mediated the effects of both global change drivers ii) In particular, strong bottom-up effects determined the system response, with herbivores responding positively and consistently more so than plants and parasitoids in particular. However, iii) this contrasting response was not explained by a phenological mismatch. iv) Food-web structure responded to the changes in composition of herbivores and parasitoids, but shifts in interaction structure did not affect the resilience of the food. However, temperature and nitrogen impacted host-parasitoid food-web structure by altering the response of parasitoid species to host density and size structuring, which is likely to bear consequences on host-parasitoid co-evolution and future food-web architecture and stability. Finally, v) we found frequent, non-additive interactions between the global change drivers. We conclude that co-occurring temperature and nitrogen are likely to alter food-web structure and overall ecosystem balance, with increasing herbivore dominance likely to have important implications for ecosystem functioning and food-web persistence.

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In this dissertation, the aim is to investigate the empirical relationship between the partial pressure of CO2 (pCO2) and other ocean variables in the Southern Ocean, by using a small percentage of the available data. CO2 is one of the main greenhouse gases that contributes to global warming and climate change. The concentration of anthropogenic CO2 in the atmosphere, however, would have been much higher if some of it was not absorbed by oceanic and terrestrial sinks. The oceans absorb and release CO2 from and to the atmosphere. Large regions in the Southern Ocean are expected to be a CO2 sink. However, the measurements of CO2 concentrations in the ocean are sparse in the Southern Ocean, and accurate values for the sinks and sources cannot be determined. In addition, it is difficult to develop accurate oceanic and ocean-atmosphere models of the Southern Ocean with the sparse observations of CO2 concentrations in this part of the ocean. In this dissertation classical techniques are investigated to determine the empirical relationship between pCO2 and other oceanic variables using in situ measurements. Additionally, sampling techniques are investigated in order to make a judicious selection of a small percentage of the total available data points in order to develop an accurate empirical relationship. Data from the SANAE49 cruise stretching between Antarctica and Cape Town are used in this dissertation. The complete data set contains 6103 data points. The maximum pCO2 value in this stretch is 436.0 μatm, the minimum is 251.2 μatm and the mean is 360.2 μatm. An empirical relationship is investigated between pCO2 and the variables Temperature (T), chlorophyll-a concentration (Chl), Mixed Layer Depth (MLD) and latitude (Lat). The methods are repeated with latitude included and excluded as variable respectively. D-optimal sampling is used to select a small percentage of the available data for determining the empirical relationship. Least squares optimization is used as one method to determine the empirical relationship. For 200 D-optimally sampled points, the pCO2 prediction with the fourth order equation yields a Root Mean Square (RMS) error of 15.39 μatm (on the estimation of pCO2) with latitude excluded as variable and a RMS error of 8.797 μatm with latitude included as variable. Radial basis function (RBF) interpolation is another method that is used to determine the empirical relationship between the variables. The RBF interpolation with 200 D-optimally sampled points yields a RMS error of 9.617 μatm with latitude excluded as variable and a RMS error of 6.716 μatm with latitude included as variable. Optimal scaling is applied to the variables in the RBF interpolation, yielding a RMS error of 9.012 μatm with latitude excluded as variable and a RMS error of 4.065 μatm with latitude included as variable for 200 D-optimally sampled points. / Thesis (MSc (Applied Mathematics))--North-West University, Potchefstroom Campus, 2012

In this dissertation, the aim is to investigate the empirical relationship between the partial pressure of CO2 (pCO2) and other ocean variables in the Southern Ocean, by using a small percentage of the available data. CO2 is one of the main greenhouse gases that contributes to global warming and climate change. The concentration of anthropogenic CO2 in the atmosphere, however, would have been much higher if some of it was not absorbed by oceanic and terrestrial sinks. The oceans absorb and release CO2 from and to the atmosphere. Large regions in the Southern Ocean are expected to be a CO2 sink. However, the measurements of CO2 concentrations in the ocean are sparse in the Southern Ocean, and accurate values for the sinks and sources cannot be determined. In addition, it is difficult to develop accurate oceanic and ocean-atmosphere models of the Southern Ocean with the sparse observations of CO2 concentrations in this part of the ocean. In this dissertation classical techniques are investigated to determine the empirical relationship between pCO2 and other oceanic variables using in situ measurements. Additionally, sampling techniques are investigated in order to make a judicious selection of a small percentage of the total available data points in order to develop an accurate empirical relationship. Data from the SANAE49 cruise stretching between Antarctica and Cape Town are used in this dissertation. The complete data set contains 6103 data points. The maximum pCO2 value in this stretch is 436.0 μatm, the minimum is 251.2 μatm and the mean is 360.2 μatm. An empirical relationship is investigated between pCO2 and the variables Temperature (T), chlorophyll-a concentration (Chl), Mixed Layer Depth (MLD) and latitude (Lat). The methods are repeated with latitude included and excluded as variable respectively. D-optimal sampling is used to select a small percentage of the available data for determining the empirical relationship. Least squares optimization is used as one method to determine the empirical relationship. For 200 D-optimally sampled points, the pCO2 prediction with the fourth order equation yields a Root Mean Square (RMS) error of 15.39 μatm (on the estimation of pCO2) with latitude excluded as variable and a RMS error of 8.797 μatm with latitude included as variable. Radial basis function (RBF) interpolation is another method that is used to determine the empirical relationship between the variables. The RBF interpolation with 200 D-optimally sampled points yields a RMS error of 9.617 μatm with latitude excluded as variable and a RMS error of 6.716 μatm with latitude included as variable. Optimal scaling is applied to the variables in the RBF interpolation, yielding a RMS error of 9.012 μatm with latitude excluded as variable and a RMS error of 4.065 μatm with latitude included as variable for 200 D-optimally sampled points. / Thesis (MSc (Applied Mathematics))--North-West University, Potchefstroom Campus, 2012

The demand for forensic social work as a specialist field is increasing rapidly, due to the increasing moral decline of the community and consequent higher demands set to generic social workers. Amendments to existing acts as well as the development of new legislation, lead to more opportunity for the prosecution of the perpetrator, and therefore a higher utilization of the forensic social worker. A need was experienced to do research regarding the gaps experienced by social workers or any other workers who are currently executing forensic assessments with the sexually traumatised child. The aim of the investigation was to determine which gaps social workers experience in the field when assessing a child forensically. A recording procedure was used to obtain qualitative as well as quantitative data. A purposive sampling was used were interviews were held with five participants to obtain the data. A selfdeveloped questionnaire was used as measuring instrument. It is clear from the findings that there are definite gaps within the field of forensic social work and the need of further research within the field of forensic social work in South Africa is highlighted. / Thesis (MIng (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2012.

Permafrost temperatures were measured by the Geological Survey of Canada (GSC) in 1977-1981 at boreholes along a proposed pipeline route in the southern Yukon. Analysis of climate station records indicate that mean annual air temperatures in the region have since increased by 0.5-1.0˚C. Renewed interest in the pipeline and the need to develop adaptation strategies for existing highway infrastructure have meant that information on permafrost and geotechnical conditions must be updated. To accomplish this goal, a total of eight GSC boreholes ranging in depth from 5-9 m were located, unblocked of ice and instrumented with thermistor cables and data-loggers to permit renewed ground temperature monitoring. Manual temperature measurements were also taken at four other shallow boreholes. Electrical resistivity tomography (ERT) surveys were conducted at each site. MAGTs below 1 m at permafrost sites in the study area range from -0.2˚C to -1.5˚C with permafrost depths greater than 25 m. The permafrost at the study sites can be classified as sporadic discontinuous and extensive discontinuous. Ground temperatures indicate that permafrost can persist under warmer climatic conditions as long as it remains protected by its ecosystem properties. Thermal monitoring for 2011-2012 shows an average increase of 0.5-1.0˚C when compared to the original 1978-1981 ground temperatures. This slow rate of ground warming is mainly attributed to a combination of limited climate change, especially in the south of the study area, ground temperatures close to 0˚C, and the possible disturbance of sites from the removal of vegetation prior to the original measurements being made. ERT surveys conducted at most borehole sites show deeper thaw or taliks where the cleared cut-line used for geophysical work in the 1970s is crossed. These results indicate the impacts of climate change and environmental change in the study area over the past three decades. They appear to match the relatively slow rates of ground warming observed elsewhere in northern Canada where permafrost temperatures are close to 0˚C and where warming also requires changes in latent heat due to internal thaw. TTOP equilibrium modelling suggests that if climate change is responsible for the ground warming, most of the change can be attributed to the step-like MAAT increase that occurred between 1975-1976.

Hypotermi, en sänkning av kroppens kärntemperatur under 36°C, är en oönskad men vanlig komplikation under den perioperativa perioden. Det är förenat med en rad negativa konsekvenser som kan orsaka lidande för patienter och innebära ökade vårdkostnader. Svårigheterna med att på ett enkelt och effektivt sätt förhindra hypotermi utgör ett hinder i vården och nya produkter utvecklas därför kontinuerligt. En viktig del i anestesisjuksköterskans arbete är att bevara patientens kroppstemperatur så nära det normala som möjligt. Syftet med föreliggande litteraturstudie var att beskriva olika metoder som är lämpliga för anestesisjuksköterskan att använda för att förhindra hypotermi hos vuxna i det perioperativa förloppet. I de 18 resultatartiklarna testades olika metoder för att bibehålla normal kroppstemperatur: täcka patienten, höjd salstemperatur, värmning med varmluft, elektrisk värmning, värmning av infusionsvätskor, värmning med cirkulerande varmvatten och strålningsvärme. Flera metoder visades effektiva men resultaten var inte entydiga. Inget system visades värma bättre än varmluft. Ytterligare forskning krävs för att fastställa nytta och säkerhet för de övriga aktiva värmesystemen men vissa kan komma att utgöra ett komplement till nuvarande strategier. / Hypothermia, a reduction of the body core temperature below 36°C, is an undesirable but common complication in the perioperative period. It is associated to a series adverse events that can cause discomfort to patients and result in increased health care costs. The difficulties involve a simple and effective way to prevent hypothermia and is an obstacle in the care and new products will develop over time. An important part of nurse anesthetists work is to maintain the patient´s body temperature as close to normal as possible. The aim of the literature study was to describe different methods that is appropriate for the nurse anesthetist to use to prevent hypothermia in adults in the perioperative process. In the results of the 18 articles different forms of methods were tested in order to maintain normal body temperature: cover the patient, raised room temperature, forced air warming, electric heating, fluid warming, warming with circulating hot water and radiant warming. Several methods were shown to be effective but the results were not conclusive. No system was demonstrated to be better than forced air warming. Further research is required to confirm the benefit and safety of the other active warming systems, but some may be in addition to current strategies.