Dissertations / Theses: 'Climatic changes Research Indonesia'

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Hartmann, Holly Chris. "Stakeholder driven research in a hydroclimatic context." Diss., FIND on the Web, 2001. http://hdl.handle.net/10150/191254.

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Nurhati, Intan Suci. "Coral records of central tropical Pacific sea-surface temperature and salinity variability over the 20th century." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/34775.

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Accurate forecasts of future regional temperature and rainfall patterns in many regions largely depend on characterizing anthropogenic trends in tropical Pacific climate. However, strong interannual to decadal-scale tropical Pacific climate variability, combined with sparse spatial and temporal coverage of instrumental climate datasets in this region, have obscured potential anthropogenic climate signals in the tropical Pacific. In this dissertation, I present sea-surface temperature (SST) and salinity proxy records that span over the 20th century using living corals from several islands in the central tropical Pacific. I reconstruct the SST proxy records via coral Sr/Ca, that are combined with coral oxygen isotopic (d18O) records to quantify changes in seawater d18O (hereafter d18Osw) as a proxy for salinity. Chapter 2 investigates the spatial and temporal character of SST and d18Osw-based salinity trends in the central tropical Pacific from 1972-1998, as revealed by corals from Palmyra (6ºN, 162ºW), Fanning (4ºN, 159ºW) and Christmas (2ºN, 157ºW) Islands. The late 20th century SST proxy records exhibit warming trends that are larger towards the equator, in line with a weakening of equatorial Pacific upwelling over this period. Freshening trends revealed by the salinity proxy records are larger at those sites most affected by the Inter-Tropical Convergence Zone (ITCZ), suggesting a strengthening and/or an equatorward shift of the ITCZ. Taken together, the late 20th century SST and salinity proxy records document warming and freshening trends that are consistent with a trend towards a weakened tropical Pacific zonal SST gradient under continued anthropogenic forcing. Chapter 3 characterizes the signatures of natural and anthropogenic variability in central tropical Pacific SST and d18Osw-based salinity over the course of 20th century using century-long coral proxy records from Palmyra. On interannual timescales, the SST proxy record from Palmyra tracks El Niño-Southern Oscillation (ENSO) variability. The salinity proxy record tracks eastern Pacific-centered ENSO events but is poorly correlated to central Pacific-centered ENSO events - the result of profound differences in precipitation and ocean advection that occur during the two types of ENSO. On decadal timescales, the coral SST proxy record is significantly correlated to the North Pacific Gyre Oscillation (NPGO), suggesting that strong dynamical links exist between the central tropical Pacific and the North Pacific. The salinity proxy record is significantly correlated to the Pacific Decadal Oscillation (PDO), but poorly correlated to the NPGO, suggesting that, as was the case with ENSO, these two modes of Pacific decadal climate variability have unique impacts on equatorial precipitation and ocean advection. However, the most striking feature of the salinity proxy record is a prominent late 20th century freshening trend that is likely related to anthropogenic climate change. Taken together, the coral data provide key constraints on tropical Pacific climate trends, and when used in combination with model simulations of 21st century climate, can be used to improve projections of regional climate in areas affected by tropical Pacific climate variability.

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Woodley, Ewan James. "Reconstructing the climate of Scotland using stable carbon and oxygen isotopes in tree-rings." Thesis, Swansea University, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.678326.

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Barbosa, Humberto. "Vegetation Dynamics Over the Northeast Region of Brazil and Their Connections With Climate Variability During the Last Two Decades of the Twentieth Century." Diss., The University of Arizona, 2004. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_2004_188_sip1_w.pdf&type=application/pdf.

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Roell, Marilee May. "Observed decadal variations of the zonal mean hygropause and its relationship to changes in the transport barrier." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45808.

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This study examines the long-term record of lower stratospheric water vapor focusing on the 20-year data record from the Stratospheric Aerosol and Gas Experiment II (SAGE II). The SAGE II zonal monthly mean water vapor data was enhanced to include the aerosol heavy late 1980s through the use of aerosol extinction filtering of the data. Comparisons between the SAGE II lower stratospheric water vapor and the Limb Infrared Monitor of the Stratosphere (LIMS), the Microwave Limb Sounder (MLS), and HALogen Occultation Experiment (HALOE) are performed. This study further focuses on the minimum lower stratospheric water vapor (i.e., hygropause) and on the dehydration seen in the hygropause with examination of the transport barrier at both the tropical tropopause and the tropopause folding region between the tropics and extra-tropics that would account for this decadal variation. The effects of aerosol contamination on the SAGE II water vapor retrievals from four volcanic eruptions from 1984 to 1992 were examined, leading to a four level filtering of the SAGE II water vapor data to allow retention of good data from early in the data record. With the improved filtered water vapor data, monthly and seasonal time series analyses show a significant decadal variation in the lower stratosphere for all months where the satellite coverage provided data from the late 1980s to the early 2000s. This decadal variation documents a decrease in the water vapor from below approximately 25 km to below the tropopause with this decrease seen in the hygropause from the tropics to the poles. Analysis of the hygropause for all months provided a statistically significant consistent neutral or decreasing value in the long-term water vapor minimum. March was shown to be the seasonal minimum in the hygropause over this 20-year low aerosol record, followed by a discontinuity in the minimum abundance after 2000. Three transport pathways for transport of water vapor from the moist troposphere to the lower stratosphere include the tropical tropopause, isentropic transport at the sub-tropical jet locations, and meridional transport from the tropics to the midlatitudes above the hygropause. The tropical tropopause temperatures were examined using the new Modern Era Retrospective-analysis for Research and Applications (MERRA) data set. Analysis showed a significant decrease in the tropical and sub-tropical tropopause temperatures over the 20-year timeframe for the DJF season preceding the March minimum. The lower temperatures would provide a colder "cold trap" at the tropopause, further "freeze drying" the air seasonally transported from the upper troposphere to the lower stratosphere, providing the long-term dehydration in the hygropause and lower stratosphere. The Ertel's Potential Vorticity (EPV or PV) was examined as a proxy for the sub-tropical jet movement towards the poles over this long-term record. Changes in this pathway location may affect the efficiency of isentropic transport of moist tropospheric air into the lower stratosphere at these higher latitudes. Analysis using the MERRA zonal EPV and maximum zonal Uwind data showed a statistically significant shift in the locations of the contours towards the SH poles over this 20-year timeframe for the DJF, DJFM seasons and the month of December. The meridional winds above the tropopause show an increase over the 20-year record covered by SAGE II water vapor data. These increasing winds are consistent with the increase in the Brewer-Dobson circulation shown in other studies. The colder tropopause temperatures along with the increasing Brewer-Dobson circulation just above the tropopause, are the likely cause for the decreasing water vapor trend as seen in the SAGE II March hygropause over the 20-years from 1986-2005.

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Robbins, John A. "Stable isotopes, marine paleoclimates, and human subsistence on California's Channel Islands." Ann Arbor, Mich. : ProQuest, 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1442835.

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Thesis (M.S. in Geology)--S.M.U., 2007.
Title from PDF title page (viewed Mar. 18, 2008). Source: Masters Abstracts International, Volume: 45-05, page: 2387. Adviser: Robert Gregory. Includes bibliographical references.

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McKechnie, Nicole R., and University of Lethbridge Faculty of Arts and Science. "Predicting climate change impacts on precipitation for western North America." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2005, 2005. http://hdl.handle.net/10133/269.

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Global Circulation Models (GCMs) are used to create projections of possible future climate characteristics under global climate change scenarios. Future local and regional precipitation scenarios can be developed by downscaling synoptic CGM data. Daily 500-mb geopotential heights from the Canadian Centre for Climate Modeling and Analysis's CGCM2 are used to represent future (2020-2050) synoptics and are compared to daily historical (1960-1990) 500-mb geopotential height reanalysis data. The comparisons are made based on manually classified synoptic patterns identified by Changnon et al. (1993.Mon. Weather Rev. 121:633-647). Multiple linear regression models are used to link the historical synoptic pattern frequencies and precipitation amounts for 372 weather stations across western North America,. The station-specific models are then used to forecast future precipitation amounts per weather station based on synoptic pattern frequencies forecast by the CGCM2 climate change forcing scenario. Spatial and temporal variations in precipitation are explored to determine monthly, seasonal and annual trends in climate change impacts on precipitation in western North America. The resulting precipitation scenarios demonstrate a decrease in precipitation from 10 to 30% on an annual basis for much of the south and western regions of the study area. Seasonal forecasts show variations of the same regions with decreases in precipitation and select regions with increases in future precipitation. A major advancement of this analysis was the application of synoptic pattern downscaling to summer precipitation scenarios for western North America.
ix, 209 leaves : col. maps ; 29 cm.

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Nemeth, Michael W., and University of Lethbridge Faculty of Arts and Science. "Climate change impacts on streamflow in the upper North Saskatchewan River Basin, Alberta." Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Geography, c2010, 2010. http://hdl.handle.net/10133/2477.

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This research focuses on the estimation of the impacts of climate change on water yield, streamflow extremes, and the streamflow regimes in the Cline River Watershed, and consequently, water availability for hydropower generation in this area. The Cline River Watershed comprises the flow into Lake Abraham, the reservoir for Bighorn Dam, is part of the upper North Saskatchewan River basin (UNSRB). This objective was achieved by parameterizing the ACRU agro-hydrological modelling system. After parameterization was complete, ACRU output was calibrated and verified against available observed data, including temperature, snow water equivalent, glacier mass balance, potential evapotranspiration, and streamflow data. After ACRU was properly verified, five selected climate change scenarios to estimate impacts of climate change in this area. Overall water yields are projected to increase over time. A large shift in seasonality is likely the biggest impact climate change will have on water resources in the Cline River Watershed.
xii, 126 leaves : ill., maps ; 29 cm

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Andrews, Shilo F., and University of Lethbridge Faculty of Arts and Science. "Tracing changes in uptake of precipitation and groundwater and associated consequences for physiology of Douglas-fir and lodgepole pine trees in montane forests of SW Alberta." Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Biological Sciences, c2009, 2009. http://hdl.handle.net/10133/2482.

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Douglas-fir (Pseudotsuga menziesii) and lodgepole pine (Pinus contorta) in southwestern Alberta were studied to determine the water sources used and the effect of changing soil moisture on tree ecophysiological function. The hydrogen stable isotope ratios of water from local groundwater and precipitation were compared to tree stem water to determine the amount of stem water coming from those two sources. There were no significant differences between species in the portion of summer precipitation taken up. However, Douglas-fir shifted towards using more groundwater as shallow soil moisture declined. In addition, Douglas-fir showed large changes in shoot water potential, but maintained relatively constant rates of oxygen evolution, whereas lodgepole pine exhibited smaller changes in shoot water potential and had severely reduced rates of oxygen evolution during mid-summer drought. Lower leaf-area to sap-wood area and higher leaf δ13C (carbon isotope composition) suggested a less efficient hydraulic system in Douglas-fir compared to lodgepole pine.
x, 91 leaves : ill. ; 29 cm

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Khayundi, Francis Mapati Bulimo. "The effects of climate change on the realisation of the right to adequate food in Kenya." Thesis, Rhodes University, 2012. http://hdl.handle.net/10962/d1003190.

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This thesis examines the interplay between the effects of climate change and human rights. It seeks to interrogate the contribution of human rights in addressing the effects of climate change on the enjoyment of the right to food in Kenya. Climate change has been recognised as a human rights issue. Despite this acknowledgement, many states are yet to deal with climate change as a growing threat to the realisation of human rights. The situation is made worse by the glacial pace in securing a binding legal agreement to tackle climate change. The thesis also reveals that despite their seemingly disparate and disconnected nature, both the human rights and climate change regimes seek to achieve the same goal albeit in different ways. The thesis argues that a considerable portion of the Kenyan population has not been able to enjoy the right to food as a result of droughts and floods. It adopts the view that, with the effects of climate change being evident, the frequency and magnitude of droughts and floods has increased with far reaching consequences on the right to food. Measures by the Kenyan government to address the food situation have always been knee jerk and inadequate in nature. This is despite the fact that Kenya is a signatory to a number of human rights instruments that deal with the right to food. With the promulgation of a new Constitution with a justiciable right to food, there is a need for the Kenyan government to meet its human rights obligations. This thesis concludes by suggesting ways in which the right to food can be applied in order to address some of the effects of climate change. It argues that by adopting a human rights approach to the right to food, the State will have to adopt measures that take into consideration the impacts of climate change. Furthermore, the State is under an obligation to engage in activities that will not contribute to climate change and negatively affect the right.

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Price, Catherine R. "Late Pleistocene and Early Holocene small mammals in South West Britain : environmental and taphonomic implications, and their role in archaeological research." Thesis, University of South Wales, 2001. https://pure.southwales.ac.uk/en/studentthesis/late-pleistocene-and-early-holocene-small-mammals-in-south-west-britain-environmental-and-taphonomic-implications-and-their-role-in-archaeological-research(0fdb87f2-abcf-4676-9bd3-0a23c9922caf).html.

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This project examines small mammal faunas from cave sites in south-west England and south Wales. The aims are threefold: To examine the rapid environmental changes taking place in the Late Pleistocene and early Holocene: To understand the processes by which small mammal remains were deposited in the caves examined: To demonstrate the value of small mammal studies as an archaeological tool. All identifiable small mammal remains from twelve selected sites are listed. Ten of the sites are new material. As the species examined here are seldom exploited by humans, the small mammals provide a record of the past environment unaffected by human selection of particular species, as might be the case in larger mammal assemblages. An examination of possible agents of accumulation is provided for each site to identify any bias introduced by prey selection. Reconstructions of the environment local to each cave at the time of deposition are offered. The evidence provided by the small mammals is related to the archaeological findings from each cave, to demonstrate the effect of human habitation of cave sites on the depositional and post-depositional processes shown by the microfauna. The environmental evidence provided by the study reflects a wider landscape rather than merely the immediate surroundings of the cave, and so gives a basis for human exploitation patterns in the area accessible from the cave. Reconstructions of the ecological mosaics formed by the rapidly changing climate of the period and the topographic variation around the cave sites are provided, demonstrating the potential complexity of the environment in which the humans and other fauna of the period existed. It is hoped that this will encourage archaeologists to look beyond the general division of environmental boundaries in this period, and to examine the local variation in habitat availability and use.

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Najafi, Mohammad Reza. "Climate Change Impact on the Spatio-Temporal Variability of Hydro-Climate Extremes." PDXScholar, 2013. https://pdxscholar.library.pdx.edu/open_access_etds/1114.

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The rising temperature of the earth due to climate change has shown to alter the variations of hydro-climate variables, including their intensities, frequencies and durations. Extreme events such as floods are, in particular, susceptible to any disturbances in climate cycles. As such it is important to provide policymakers with sufficient knowledge about the probable impacts of climate change on hydrologic extremes and most importantly on floods, which have the highest impacts on the societies. For this reason analysis of hydro-climate extremes is commonly performed using data at each site (or grid cell), however due to the limited number of extreme events, these analyses are not robust. Current methods, such as the regional frequency analysis, which combine data from different locations are incapable of incorporating the spatial structure of the data as well as other explanatory variables, and do not explicitly, assess the uncertainties. In this thesis the spatial hierarchical Bayesian model is proposed for hydro-climate extreme analyses using data recorded at each site or grid. This method combines limited number of data from different locations, estimates the uncertainties in different stages of the hierarchy, incorporates additional explanatory variables (covariates), and can be used to estimate extreme events at un-gaged sites. The first project develops a spatial hierarchical Bayesian method to model the extreme runoffs over two spatial domains in the Columbia River Basin, U.S. The model is also employed to estimate floods with different return levels within time slices of fifteen years in order to detect possible trends in runoff extremes. Continuing on the extreme analysis, the impact of climate change on runoff extremes is investigated over the whole Pacific Northwest (PNW). This study aims to address the question of how the runoff extremes will change in the future compared to the historical time period, investigate the different behaviors of the regional climate models (RCMs) regarding the runoff extremes, and assess the seasonal variations of runoff extremes. Given the increasing number of climate model simulations the goal of the third project is to provide a multi-model ensemble average of hydro-climate extremes and characterize the inherent uncertainties. Outputs from several regional climate models provided by NARCCAP are considered for the analysis in all seasons. Three combination scenarios are defined and compared for multi-modeling of extreme runoffs. The biases of each scenario are calculated and the scenario with the least bias is selected for projecting seasonal runoff extremes. The aim of the fourth project is to quantify and compare the uncertainties regarding global climate models to the ones from the hydrologic model structures in climate change impact studies. Various methods have been proposed to downscale the coarse resolution General Circulation Model (GCM) climatological variables to the fine scale regional variables; however fewer studies have been focused on the selection of GCM predictors. Additionally, the results obtained from one downscaling technique may not be robust and the uncertainties related to the downscaling scheme are not realized. To address these issues, in the fifth study we employed Independent Component Analysis (ICA) for predictor selection which determines spatially independent GCM variables (as discussed in Appendix A). Cross validation of the independent components is employed to find the predictor combination that describes the regional precipitation over the upper Willamette basin with minimum error. These climate variables along with the observed precipitation are used to calibrate three downscaling models: Multi Linear Regression (MLR), Support Vector Machine (SVM) and Adaptive-Network-Based Fuzzy Inference System (ANFIS).

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Langmaid, Kimberly Ford. "Seeing Shifts: Ecologists' Lived Experiences of Climate Change in Mountains of the American West." [Yellow Springs, Ohio] : Antioch University, 2009. http://etd.ohiolink.edu/view.cgi?acc_num=antioch1244125357.

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Thesis (Ph. D.)--Antioch University New England, 2009.
Title from PDF t.p. (viewed Aug. 7, 2009). "A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy Environmental Studies at Antioch University New England (2009)."--The title page. Advisor: Mitchell Thomashow, Ph. D. Includes bibliographical references (p. 184-196).

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Baldanzi, Simone. "Inter-individual variability and phenotypic plasticity : the effect of the environment on the biogeography, population structure, ecophysiology and reproduction of the sandhoppers Talorchestia capensis and Africorchestia quadrispinosa." Thesis, Rhodes University, 2014. http://hdl.handle.net/10962/d1011447.

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Climatic envelope models focus on the climatic variables affecting species or species assemblages, and are important tools to investigate the effect of climate change on their geographical ranges. These models have largely been proposed in order to make successful predictions on species‘ persistence, determining which variables are likely to induce range expansion, contraction, or shifting. More recent models, including the ability and the cost for individuals to respond promptly to an environmental stimulus, have revealed that species may express phenotypic plasticity able to induce adaptation to the new environment. Consequently, understanding how species evolve to a changing climate is fundamental. From this perspective, investigating intraspecific responses to an environmental variable may contribute to better understanding and prediction of the effect of climate change on the geographical range and evolution of species, particularly in the case of widespread species. In this context, the present study aimed at establishing how environmental variables (focussing mainly on temperature) may have contributed to shape the spatial distribution, physiology, reproductive biology and connectivity of two species of Southern African sandhoppers (Talorchestia capensis and Africorchestia quadrispinosa, Amphipoda, Talitridae). Most of the work was carried out on T. capensis, due to its widespread spatial distribution. A first investigation of the biogeography of T. capensis and A. quadrispinosa, revealed that, for both species, spatial patterns of abundance, size and sex ratio were not explained by the Abundant Centre Hypothesis (greater abundance at the core of a spatial range), but rather guided by bio-physical forces. Precisely, the abundance of sandhoppers was driven by the morphodynamic state of the beach, salinity and temperatures, with strong differentiation among sites that reflected local environmental conditions. In support of these findings, strong population structure in the genetics of T. capensis was found (three main groups) when investigating its phylogeography and genetic connectivity. Although such defined structure may suggests cryptic speciation, the concomitant within-population variation in the COX1 region of mtDNA, also highlighted the importance of individual genetic variability. High individual variability was also found in the response of T. capensis to temperature, both in its physiology (thermal plasticity) and its reproductive biology (maternal effects). Since temperature is one of the main variables affecting the coastal marine systems of southern Africa and the metabolism of animals in general, its effect on the physiology and reproduction of T. capensis was therefore investigated. Thermal responses to increasing/decreasing temperatures were assessed for separated populations of T. capensis. Individual variability was reported in the oxygen consumption of T. capensis in response to temperature (high variation around the means, especially for increasing temperatures). Among population differences in thermal sensitivity were significantly correlated with air temperature variability experienced over the past 23 years, highlighting the importance of historical temperature fluctuations to the current thermal physiology of these sandhoppers. Temperature also had an important effect on the reproductive plasticity of T. capensis. Different temperatures induced mothers to adjust the size of their offspring (i.e. egg size), with larger eggs produced at lower temperatures. Interestingly, females showed strongly significant among individual variation in the size of the eggs. Given the importance of understanding rapid responses of organisms to climate change and considering the fundamental role played by phenotypic plasticity in evolution, the overall study revealed the significance of individual plasticity and variability in response to the environment and highlighted its importance. Particularly, studying the thermal physiology of separated populations and understanding within population reproductive plasticity in response to temperature, helped to clarify how differences among individual responses have important consequences at the population level, possibly explaining the widespread distribution of T. capensis.

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Parkin, Simon J. "Valuing the vernacular : Scotland's earth-built heritage and the impacts of climate change." Thesis, University of Stirling, 2014. http://hdl.handle.net/1893/22126.

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Scotland’s vernacular earth-built heritage has received inadequate recognition over a number of decades, being the reserve of a small group of academic, architectural and conservation practitioners, with negative perceptions of the structures and their inhabitants having been developed over the long-term. This has ultimately contributed to the loss of a wide number of earth building traditions previously widespread across Scotland. Heritage custodians have invested in the restoration and maintenance of a select few sites, but wider recognition of the significance of extant structures, including the intangible aspects of inherited traditions, remains limited. This thesis therefore seeks in the first instance to promote improved understandings of Scotland’s earth-built heritage through historical appraisals that underline its wider heritage value within global, regional and local contexts, whilst demonstrating the limitations of survey evidence hitherto relied upon. Heritage policies and management procedures are increasingly driven in response to the climate changes projected for the remainder of the twenty-first century, partly informed by the impacts of changes that have already been observed. As a result of this, new fields of research such as heritage climatology have developed with a view to offering bases from which to develop longer term mitigation and management strategies that recognise potential changes to the causes and processes of deterioration in the historic environment. Alongside the development of academic interest in climate and heritage has been an ever-increasing accessibility to advanced analysis methods through technical apparatus (often portable) that can be used to create improved evidence repositories based on processes-led approaches to investigation. Scotland’s earth-built heritage is susceptible to a range of climate-related phenomena that are likely to manifest in different ways over coming decades. Conservation strategies have continued to rely, however, upon the empirical observations and the experience of very few individuals since the latter-twentieth century. Consequently, the ad hoc approaches to the management of Scotland’s earth-built heritage and lack of strategic planning that have been typical to this point require amendment. This interdisciplinary thesis therefore seeks to contribute to addressing the issues outlined above through the exploration and application of portable scientific sampling apparatus that allow for in situ, rapid and non-intrusive insights to be gained at various scales of interest. These, together with other minimally intrusive approaches to assessing performance in earth building materials, allow for the development of processes-led strategies to extending the evidence base beyond that presently relied upon. Amongst the key outcomes of this are the generation of a locally-focused dataset of climate projections that are used to develop understandings of future climate conditions in the Carse of Gowrie, Perthshire, and in turn garner insights as to how these will impact in relation to the earth-built heritage for which this region is noted. Temperature and humidity monitoring evidence gathered from within the walls of extant structures over the course of fourteen months from March 2012 to April 2013 are set against contemporary external weather conditions and alongside measurements of moisture ingress. These serve to highlight both aspects of inherent resilience and points of particular risk to the future integrity of earth-built structures. An extended benefit of this work is the demonstration that the novel procedures used are easily replicated and could be employed in a variety of local contexts to develop suites of intra-site data across Scotland, with the potential for offering evidence-based inferences relevant to management procedures and policy discussion. The utility of the understandings and methods of investigation long established in the field of soil science but conspicuously overlooked in earth buildings research is also addressed, with insights into micro-scale processes offered using micromorphological and micromorphometric methods and the results being directly related to macro-scale observations.

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Sleadd, Isaac Martin. "CCAAT/Enhancer-Binding Protein Delta (C/EBP-delta) Expression in Antarctic Fishes: Implications for Cell Cycle and Apoptosis." PDXScholar, 2013. https://pdxscholar.library.pdx.edu/open_access_etds/994.

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Chapter 1: Antarctic fishes are extremely cold adapted. Despite their inability to upregulate heat shock proteins, recent studies have demonstrated a capacity for heat response in these animals. A cDNA microarray study looked at the Notothenioid fish Trematomus bernacchii and revealed heat sensitivities for hundreds of genes, two of which code for members of the CCAAT/Enhancer-binding protein (C/EBP) family of transcription factors. These molecular switches are best known for their roles in apoptosis, inflammation and cell cycle arrest. This dissertation further elucidates the role of C/EBP-delta in the Antarctic fishes T. bernacchii and Pagothenia borchgrevinki. Chapter 2: C/EBP-delta is constitutively expressed in unstressed, field-acclimated (ca. -1.86°C) animals in a highly tissue-specific manner. White muscle tissue contains the highest C/EBP-delta concentration, which is further increased in response to sublethal heat stress at 2.0 or 4.0°C. This response is mostly acute and transitory, but a lesser upregulation was observed in fishes held for one month at 4.0°C. Chapter 3: The heat-induced nuclear translocation of C/EBP-delta--as determined by immunohistochemistry--appears to be time, tissue and species specific with spleen, heart and retinae being particularly responsive in certain situations. Chapter 4: Protein concentrations of proliferating cell nuclear antigen are tissue specific and variably heat responsive. Surprisingly, levels appear to be positively correlated with C/EBP-delta. Chapter 5: Flow cytometry revealed increasingly high temperatures reduce the proportion of G1 cells while increasing the abundance of apoptotic cells. Chapter 6: These findings are discussed in the context of global climate change and the cellular stress response.

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Aljazairi, López Salvador. "Estudio del impacto de las concentraciones altas y bajas de CO2 sobre el cultivo de trigo." Doctoral thesis, Universitat de Barcelona, 2014. http://hdl.handle.net/10803/286184.

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Desde el último periodo glacial hasta la Revolución Industrial, la [CO2] atmosférica se mantuvo constante entorno a los 200-260 ppm de CO2 durante miles de años. Sin embargo, desde el inicio de la Revolución Industrial la [CO2] atmosférica está aumentando rápida y continuamente debido a las actividades humanas. La [CO2] atmosférica actual está prácticamente a 400 ppm según NOAA-ESRL, 2014. Este incremento en la [CO2] atmosférica y otros gases de efecto invernadero están afectando el clima tanto local como global y están asociados a cambios en la temperatura y en los regímenes hídricos. A este efecto a nivel global se le denomina “Cambio Climático”. El informe IPCC 2014 da predicciones utilizando modelos que indican un aumento de la [CO2] atmosférica de hasta 985 ppm para el final de siglo. Uno de los temas importantes de investigación relacionado con la variación de la [CO2] atmosférica es la aclimatación de la fotosíntesis de las plantas a los diferentes niveles de CO2. La aclimatación fotosintética es el proceso de ajuste fisiológico de las plantas a una determinada [CO2]. Las plantas pueden experimentar incrementos de la fotosíntesis en el caso de bajas [CO2] (regulación a la alta), y disminuciones de la fotosíntesis a altas [CO2] (regulación a la baja), a través de ajustes en la maquinaria fotosintética. Sin embargo, el grado de aclimatación fotosintética de las diferentes especies, puede variar dependiendo de otros factores tanto intrínsecos como ambientales como la relación fuente de carbono y sumidero de carbono, estado nutricional de la planta o estreses como por ejemplo la sequía o la temperatura. Las plantas sometidas a baja [CO2] atmosférica y en condiciones ideales de crecimiento, han sufrido una regulación a la alta de la fotosíntesis, mayor conductancia estomática (se mantienen abiertos los estomas para permitir una mayor entrada de CO2), con un incremento en el nivel de proteínas en hoja como por ejemplo la Rubisco, un aumento del contenido de N en hoja, o una mayor inversión de C en la parte aérea (para tener más superficie de captación de CO2) y una menor inversión de C en la raíz. Una de las razones de la importancia de los estudios a baja [CO2] es por que entender la adaptación de las plantas a bajas [CO2] y como se han vuelto a adaptar a las [CO2] actuales, nos podrán ayudar a entender cómo evolucionarán en el futuro con el incremento constante del nivel de CO2 atmósferico. Por otro lado, la exposición de la planta a una elevada [CO2] inicialmente estimula el crecimiento de esta e incrementa la tasa de fotosíntesis, en algunos casos más del 40%. Sin embargo, una exposición prolongada de la planta a una elevada [CO2] hace que haya un ajuste de la maquinaria fotosintética, con una regulación a la baja de ésta. Debido a la estimulación inicial de la fotosíntesis, hay una mayor producción de carbohidratos en la hoja, cuando la producción de carbohidratos es mayor a la demanda de la planta, éstos comienzan a acumularse en la hoja y se produce la reducción de la Rubisco y otras proteinas para disminuir la producción de carbohidratos. Hay otros cambios asociados a la elevada [CO2] como es la disminución del contenido de N en hoja, o un aumento de la producción de la raíz en comparación con niveles menores de CO2 en la atmósfera (lo que incrementa la captación de nutrientes o agua del suelo al tener una mayor zona de exploración). Las plantas que han crecido a elevadas [CO2] controlan mejor la perdida de agua a través del cierre de estomas. Las plantas reducen la pérdida de agua y aumentan la EUA como resultado de la estimulación de la fotosíntesis y la reducción de la gs. En esta Tesis se muestra cómo las plantas de trigo sometidas a una [CO2] preindustrial proporcionan información sobre el comportamiento y la adaptación del trigo al futuro incremento de [CO2]. Además futuras [CO2] atmosféricas estarán asociadas a un aumento en las temperaturas y periodos de sequía, modificando el clima y causando un daño en los ecosistemas (IPCC 2014). Asimismo se han realizado diferentes estudios de la importancia de estas adaptaciones fisiológicas en la respuesta de dos variedades de trigo duro (capítulos 1 y 2) con el cambio climático a [CO2] futuras y preindustriales (capítulos 1, 2 y 3
Wheat is one of the most important cereal food crops in the world today. The productivity and quality of this crop is greatly affected by environmental conditions during grain filling. In this Tesis, we have analyzed two genotypes of durum wheat, Blanqueta and Sula (traditional and a modern wheat respectively) Plants were grown from the seedling stage in three fully controllable plant-growth chambers for one growing season and at three different CO2 levels (i.e. 260, 400 and 700 ppm). On the other hand we analyzed the modulation of drought stress in plants grown at the different CO2 environments. Plant growth and physiological parameters were analyzed during anthesis and grain filling in order to study the capacity of these plants to create new sinks and their role during the process of the acclimation of photosynthesis. Besides, the results of a simultaneous 13C and 15N labeling experiment were also presented. It was observed that plants underwent photosynthetic acclimation at pre-industrial and future [CO2] (up and down-regulation respectively). However, the modern genotype averts the process of down-regulation by creating a new carbon sink (i.e. the spike). Here, we have shown the essential role that the spike plays as a new sink in order to avert the down-regulation of photosynthesis at future [CO2]. Moreover, we have demonstrated that at future [CO2] the growth response will depend on the ability of plants to develop new sinks or expand existing ones. 13C labeling revealed that at pre-industrial CO2 carbon investment by plants was higher in shoots, whereas at future CO2 more carbon was invested in roots. Furthermore, the modern genotype invested more carbon in spikes than did the traditional genotype, which in turn invested more in non-reproductive shoot tissue. 15N labeling revealed that the modern genotype was better adapted to assimilating N at higher CO2 levels, whereas the traditional genotype was able to assimilate N more efficiently at lower CO2 levels. We showed that [CO2] effects on plants are modulated by water availability. Plants at depleted [CO2] combined with drought has a more negative impact on plants with decreases in C assimilation and biomass. Plants exposed to a combination of elevated [CO2] and WS were the most negatively affected (e.g. on plant biomass).

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Somers, Rabia. "Assessing Seychelles' vulnerability and adaptation to a historical landslide disaster through archival research." Thesis, 2017. http://hdl.handle.net/10539/23503.

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A research report submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Science. 5 June 2017 in Johannesburg
Global climate change and its related actual and potential impacts to society has called for studies that look to the past to better understand historical climate trends and how they may inform future climate trends. Specific in this area of research is environmental histories, wherein information on historical climate events and disasters are retrieved from historical documentary sources, i.e. archives, in order to study the potential causes and effects of these occurrences, as well as levels of vulnerability and resilience through the analysis of coping and adaptation strategies of societies.
MT 2017

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Chu, Wing Yin. "Variability of Subglacial Drainage Across the Greenland Ice Sheet: A Joint Model/Radar Study." Thesis, 2017. https://doi.org/10.7916/D8348XSV.

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Over the last several decades, the majority of the Greenland outlet glaciers have accelerated due to the increased warming in both the atmosphere and the oceans around the polar latitudes. While there is a clear overall acceleration trend over this period, there is significant variability in the glacier responses to climate on seasonal and year-to-year timescales. This variability observed around Greenland is very likely tied to the differences in internal dynamics of individual glaciers and the complex interaction with its local environment. Here I investigate the interaction between ice and water along the ice base as an important mechanism contributing to the observed variability among glaciers in Greenland. I use a range of modeling and radar sounding approaches to study the subglacial hydrology for three types of outlet glaciers, including slow moving, marine terminating glaciers in the west, a land-terminating system in the southwest, and a fast moving, marine-terminating glacier in northern Greenland. These case studies allow me to characterize the basal water distribution, its variability throughout the year and how this drainage behavior varies across different regions of Greenland. To start, I use a hydrological routing model to characterize the subglacial hydrology for three neighboring slow moving (< 100myr−1), marine terminating glaciers in western Greenland. The hydrologic model allows me to examine the sensitivity of basal water routing to subtle changes in basal water pressures. My results reveal that Greenland subglacial drainage can be rerouted across 100’s of km in response to changes in basal water pressures as small as 10%. I conclude that water piracy and subsequent dramatic changes in ice velocity, similar to that observed around the Siple Coast in West Antarctica, can occur in Greenland. Next, I move to a more data-orientated approach and use airborne radar sounding to examine the seasonal variability of basal water distribution. To robustly characterize basal water from radar bed power, I use a novel radar analysis approach that integrates a thermomechanical ice-sheet model to predict the spatial variations of radar attenuation. I improve this approach by including a least-squares minimization to correct for power offsets due to the different radar systems deployed in multiple field seasons. This improved method is first applied to two land-terminating glaciers in the southwest, Russell Glacier, and Isunnguata Sermia. Using two seasons of radar sounding data, I find that the basal water distribution can change between the wintertime and the summertime. My results reveal that during the winter, water resides primarily in small pockets on top of bedrock ridges. In the summer, these pockets of water on the ridges connect and drain into the nearby basal troughs. This seasonal shift in the basal water distribution is actively controlled by the material properties of the bed. Therefore, in addition to the bed topography, the permeability of the bed and the presence of basal sediments could also exert a critical influence on the seasonal development of subglacial drainage. Finally, I apply the radar analysis approach to a fast-flowing marine terminating glacier for Petermann Glacier in Northern Greenland. Here I incorporate an additional step to address the spatial variation in ice chemistry and its effect on radar attenuation. I use this approach to examine the relationship between basal water, ice deformation and the onset of glacier flow. In addition to finding basal water in the fastest flowing region near the ice margin, I identify substantial basal water in the ice sheet interior where meltwater must either be related to the advection of water from upstream or be generated by internal heating due to ice deformation. My results show there are three basal water networks beneath Petermann that connect the ice sheet interior to the margin. Together, the interaction between these basal water networks and the ice deformation enhances and sustains fast flow in the interior of the Petermann catchment. Overall, the research presented in this dissertation suggests that subglacial hydrology is high variable in both space and time. This variation in the hydrologic system can influence the fundamental structure of the ice sheet through changing the transport and storage of basal water and through interacting with ice deformation and the thermal properties of the bed.

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Weston, Michael John. "Modelling isoprene emissions over Southern Africa based on climate change scenarios." Thesis, 2012. http://hdl.handle.net/10539/11356.

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M.Sc., Faculty of Science, University of the Witwatersrand, 2011
Biogenic volatile organic compounds (BVOCs), in the presence of nitrogen oxide gases (NOx), play a role in the production of tropospheric ozone (O3) which is an effective greenhouse gas and is hazardous to human health (Haagen-Smit, 1952, Chameides et al, 1988, Atkinson, 2000, Kanakidou et al, 2004). Isoprene is a single BVOC that accounts for over 50% of all emitted BVOCs. Isoprene emissions are species specific and vary according to temperature, light and leaf area index. Climate change studies predict that the geographic distribution of species, temperature ranges, light intensity and leaf area index will shift, thus altering future isoprene emissions. Several attempts to model BVOC emissions have been undertaken in an effort to quantify BVOC emission rates and the impact on ozone formation. The most widely used and empirically tested emission algorithms to date were developed by Guenther et al (1993) and are incorporated into the emission model Model of Emissions of Gases and Aerosols from Nature (MEGAN). MEGAN is used in this study to model isoprene emission rates over southern Africa under current and future climate conditions. Current and future climate conditions are taken from the regional climate model, Conformal-Cubic Atmospheric Model (C-CAM), which has been shown to simulate current climate well for the region. Emissions were modelled for January and July only, to represent summer and winter conditions. January isoprene emission rates for the current climate range from 0 to 1.41 gm-2month-1 and total 0.938 Tg of isoprene for the study domain. The highest emission rates are caused by combinations of driving variables which are: high temperature only; high temperature and high leaf area index; high emission factor and high leaf area index. Emission rates effectively shut down in July due to low temperatures and low leaf area index. July emission rates range from 0 to 0.61 gm-2month-1 and total 0.208 Tg of isoprene. Temperature is shown to cause the greatest variation in isoprene emission rates, and thus future scenarios represent an increase in temperature only. The spatial distribution of future emission rates does not shift when compared to current emission rates, but does show an increase in magnitude. Future emission totals for January increase iv by 34% to 1.259 Tg of isoprene and the July emission total increases by 38% to 0.289 Tg of isoprene. Future emission rates responded to temperature as expected, increasing in magnitude, rate of change and range of temperature over which the greatest rate of change occurs. Three areas demonstrating the highest increase in emission rates and highest future emission rates were identified. As temperature was the only variable altered in future scenarios, these areas can be deemed as areas most sensitive to changes in temperature. These areas are situated near the Angola-Namibia border, the Northern Interior of South Africa and the low-lying areas of Mozambique.

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Warburton, Michele Lynn. "Detection of changes in temperature and streamflow parameters over Southern Africa." Thesis, 2005. http://hdl.handle.net/10413/3514.

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It has become accepted that long-term global mean temperatures have increased over the twentieth century. However, whether or not climate change can be detected at a local or regional scale is still questionable. The numerous new record highs and lows of temperatures recorded over South Africa for 2003, 2004 and 2005 provide reason to examine whether changes can already be detected in southern Africa's temperature record and modelled hydrological responses. As a preface to a temperature detection study, a literature reVIew on temperature detection studies, methods used and data problems encountered, was undertaken. Simple statistics, linear regression and the Mann-Kendall non-parametric test were the methods reviewed for detecting change. Southern Africa's temperature record was thereafter examined for changes, and the Mann-Kendall non-parametric test was applied to time series of annual means of minimum and maximum temperature, summer means of maximum temperature and winter means of minimum temperature. Furthermore, changes in the upper and lower ends of the temperature distribution were examined. The Mann-Kendall test was applied to numbers of days and numbers of 3 consecutive days abovelbelow thresholds of 10th and 90th percentiles of minimum and maximum temperatures, as well as abovelbelow threshold values of minimum (i.e. 0°) and maximum (i.e. 40°C) temperatures. A second analysis, using the split sample technique for the periods 1950 - 1970 vs 1980 - 2000, was performed for annual means of daily maximum and minimum temperatures, summer means of daily maximum temperatures, winter means of daily minimum temperatures and coefficients of variability of daily maximum and minimum temperatures. Two clear clusters of warming emerged from almost every analysis, viz. a cluster of stations in the Western Cape and a cluster of stations around the midlands ofKwaZulu-Natal, along with a band of stations along the KwaZulu-Natal coast. Another fmding was a less severe frost season over the Free State and Northern Cape. While certain changes are, therefore, evident in temperature parameters, the changes are not uniform across southern Africa. Precipitation and evaporation are the primary drivers of the hydrological cycle, with temperature an important factor in the evaporation process. Thus, with changes in various temperature parameters having been identified over many parts of southern Africa, the question arose whether any changes were evident as yet in hydrological responses. The ACRU model was used to generate daily streamflow values and associated hydrological responses from a baseline land cover, thus eliminating all possible human influences on the catchment and channel. A split-sample analysis of the simulated hydrological responses for the 1950 - 1969 vs 1980 - 1999 periods was undertaken. Trends over time in simulated streamflows were examined for medians, dry and wet years, as well as the range between wet and dry years. The seasonality and concentration of streamflows between the periods 1950 - 1969 and 1980 - 1999 were examined to determine if changes could be identified. Some trends found were marked over large parts of Primary Catchments, and certainly require consideration in future water resources planning. With strong changes over time in simulated hydrological responses already evident in certain Primary Catchments of South Africa using daily rainfall input data from 1950 1999, it, therefore, became necessary to examine the rainfall regimes of the Quaternary Catchments' "driver" rainfall station data in order to determine if these hydrological response changes were supported by changes in rainfall patterns over time. A splitsample analysis was, therefore, performed on the rainfall input of each Quaternary Catchment. Not only were medians considered, but the higher and lower ends of the rainfall distributions were also analysed, as were the number of rainfall events above pre-defined daily thresholds. The changes evident over time in rainfall patterns over southern Africa were found to vary from relatively unsubstantial increases or decreases to significant increase and decreases. However, the changes in rainfall corresponded with the changes noted in simulated streamflow. From the analyses conducted in this study, it has become clear that South Africa's temperature and rainfall, as well as hydrological responses, have changed over the recent past, particularly in certain identifiable hotspots, viz. the Western Cape and KwaZulu-Natal where significant increases in temperature variables and changes in rainfall patterns were detected. These detected changes in climate need to be considered in future water resources planning.
Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2005.

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Rosenberg, Eureta, Presha Ramsarup, Sibusisiwe Gumede, and Heila 1965 Lotz-Sisitka. "Building capacity for green, just and sustainable futures – a new knowledge field requiring transformative research methodology." 2016. http://hdl.handle.net/10962/59613.

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Education has contributed to a society-wide awareness of environmental issues, and we are increasingly confronted with the need for new ways to generate energy, save water and reduce pollution. Thus new forms of work are emerging and government, employers and educators need to know what ‘green’ skills South Africa needs and has. This creates a new demand for ‘green skills’ research. We propose that this new knowledge field – like some other educational fields – requires a transformative approach to research methodology. In conducting reviews of existing research, we found that a transformative approach requires a reframing of key concepts commonly used in researching work and learning; multi-layered, mixed method studies; researching within and across diverse knowledge fields including non-traditional fields; and both newly configured national platforms and new conceptual frameworks to help us integrate coherently across these. Critical realism is presented as a helpful underpinning for such conceptual frameworks, and implications for how universities prepare educational researchers are flagged.

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23

Sandstrom, Robert Michael. "Geochronology and reconstruction of Quaternary and Neogene sea-level highstands." Thesis, 2021. https://doi.org/10.7916/d8-1xn4-vb62.

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Understanding the past sensitivity of ice sheets and sea level rise in a warmer climate is essential to future coastal planning under the threat of climate change, as accurately modeling impending scenarios depends primarily on data from the past. Extreme warm events during the Quaternary and Neogene periods hold much of the information needed to predict future global climate conditions due to anthropogenic and natural forcings, and may provide unique glimpses of how much future sea level rise can be expected on both short- and long-term timescales. Constraining global mean sea level (GMSL) during past warm periods becomes increasingly difficult the further back in time one goes, especially as precise dating of globally distributed paleoshorelines, along with long-term vertical displacement rates, is essential for establishing GMSL and ice volume history. However, placing chronological constraints on shorelines beyond the limit of U-series radiometric dating (~600 kyr), or at high latitude sites lacking coral, has remained elusive. Even relatively recent warm periods, such as the Last Interglacial (~117-129 ka) has proved challenging for reconstructing GMSL, primarily due to uncertainties in long-term vertical deformation rates and timing of when the highstand occurred. The first two chapters of this thesis address the dating of carbonate shorelines older than ~500 kyr through refinement of the strontium isotope stratigraphy dating methodology. I apply these techniques to a well-known location with numerous uplifted fossil shorelines (Cape Range, Western Australia) to provide the first geochemically derived ages on three fossil shorelines spanning the Pleistocene to the Miocene. Accurate dating and mapping at this location allows correction of long-term vertical displacement. In the last chapter, I use these rates of uplift, in conjunction with twenty new 230Th/U-ages on corals from Western Australia, to refine the timing and peak elevation of the Last Interglacial sea level highstand. Chapter 1 re-evaluates strontium isotope stratigraphy dating techniques for chronologically constraining fossil shorelines from ~0.5 to >30 Ma. Using marine terraces from South Africa, Western Australia, and the Eastern United States as examples, this chapter presents a refined sampling and dating methodology to overcome limitations on diagenetically altered samples, which are ubiquitous in older carbonate shorelines. Discussion on best practices for constraining maximum or minimum ages includes a novel scoring methodology for alteration and a sequential leaching procedure that is specifically suited for shallow-water biogenic carbonate fauna. In Chapter 2, I apply the revised strontium isotope stratigraphy dating methodology to three previously unknown aged terraces in Cape Range, Western Australia. The results obtained show Late-Miocene, Late-Pliocene and Mid-Pleistocene shorelines, which I then use to reconstruct the vertical uplift history of the anticlinal structure and relative rates of deformation. This study is the first to directly date the three terraces, and provides the deformation history necessary for constraining Last Interglacial sea level at Cape Range. In addition, we are able to place maximum relative sea level constraints on all three of these older shorelines. Chapter 3 builds upon the previous chapter by focusing on the Last Interglacial sea level history along ~300 km of coastline in Western Australia (Cape Range and Quobba). This chapter presents new U-series ages on multiple coral heads that are among the highest in-situ corals ever dated in Western Australia, with ages spanning from ~125.3 – 122.6 ka. Detailed geomorphic analysis, particularly at Cape Range, constrains the relative sea level highstand to 6.9 ± 0.4 m. When glacial isostatic adjustment models are applied to the age and elevation data, the resulting Eemian GMSL highstand occurred between 125.5-123.0 ka and reached an elevation between 4.9 and 6.7 m. This is later in the Interglacial and lower in elevation than many recent studies suggest. This dissertation focuses on refining sea level highstands from the Last Interglacial to the Late Miocene in a relatively small (but historically important) region of Western Australia. However, the methodologies presented here provide a powerful multi-proxy dating and mapping approach, which, when applied to regions with multiple marine terraces, can greatly improve the reliability of younger shoreline elevations by reducing neotectonic and dynamic topography uncertainties. The carbonate screening techniques and 87Sr/86Sr stratigraphy dating described here are applicable to a wide range of marine carbonates, with the ability to place accurate chronologic constraints on shorelines from 0.5 to >30 Ma. As I show in chapter 3, when combined with 230Th/U-dating on Late Pleistocene coral in places where multiple marine terraces exist, valuable long-term vertical deformation constraints can allow for far more accurate analysis of sea level in younger paleo shorelines (i.e. Last Interglacial).

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Sithole, Mthokozisi. "Incorporation of climate change in institutional investors’ short-term investment decision-making." Diss., 2014. http://hdl.handle.net/2263/44454.

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The issue leading to this study is the purported lack of short-term consideration of climate change materiality on investment portfolios. The on-going research argument deliberates the roles and motives of institutional investors in considering environmental, social and governance (ESG) issues, including climate change, in investment decisions. The purpose of this study was therefore to explore the underlying motives of South African institutional investors for the incorporation of climate change in their short-term investment decision-making. The study was conducted through a qualitative, exploratory enquiry, whereby seven semi-structured interviews were conducted with institutions in the South African asset management industry. Participants’ views were analysed and indicated the following themes: The state of climate change awareness and the incorporation of ESG and climate change in investment decision-making; tactical valuation of assets using ESG/climate change screening and methods of monitoring ESG/climate change practices; and motives, incentives and constraints of responsible investment (RI) practices to incorporate climate change. These are supported by business conditions that enable consideration of climate change in investment analysis. Industry practitioners can lead by implementing RI to include climate change in order to attract potential clients to their portfolios.
Dissertation (MBA)--University of Pretoria, 2014.
zkgibs2015
Gordon Institute of Business Science (GIBS)
Unrestricted

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25

Forster, Hale A. "Saving Money or Saving Energy? Decision Architecture and Decision Modes to Encourage Energy Saving Behaviors." Thesis, 2020. https://doi.org/10.7916/d8-wbjn-4w80.

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Reducing energy use is a critical near-term strategy to mitigate climate change. Energy savings behaviors provide multiple benefits to the consumer and to society in addition to reducing greenhouse gas emissions: financial savings from lower energy bills, improved home comfort, fossil fuel resource conservation, energy independence, and improved local and indoor air quality, among others. Yet many policies to encourage reductions in energy use continue to focus on motivating behavior change with financial benefits, and little behavioral research has explored how these multiple benefits influence energy use decisions. Given the continued need for decreased energy use, more research is needed on how to leverage both financial and nonfinancial motivations to encourage energy saving behaviors. This dissertation consists of three separate papers, each addressing different elements of how individuals integrate financial and nonfinancial benefits to make energy use decisions. It presents the results of eight online and field studies conducted with over 395,000 U.S. residents. Chapters 1 and 2 focus on the decision architecture of the presentation of multiple benefits. Chapter 1 develops an inconspicuous change in savings metric to gently nudge individuals to consider energy use in addition to financial savings. It shows that presenting energy savings as a percentage of end-use energy increases behavioral adoption compared to a standard presentation of dollars saved. Chapter 2 explicitly presents environmental benefits in different ways, examining whether message effectiveness differs according to participants’ political ideologies. It shows that presenting environmental benefits in addition to financial benefits can increase interest in a large energy efficiency investment. Furthermore, while environmental benefits framed as climate change are motivating only for liberals, environmental benefits framed as stewardship and energy independence are motivating for both liberals and conservatives. Chapter 3 develops a measurement scale for a potential mechanism explaining why environmental and financial benefit frames lead to different decision outcomes: decision modes, or the qualitatively different ways that people make decisions. It defines six decision modes: calculation, affect, social norms, identity, habitual, and moral. These papers contribute to the behavioral science literature, expanding our understanding of the ways that decision makers incorporate the financial and environmental benefits of energy saving behaviors when making energy savings choices. These papers also provide actionable insights for policy makers to decrease energy consumption by improving the presentation of energy saving decisions.

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26

Webber, J. Jeremy III. "Statistical downscaling of MODIS thermal imagery to Landsat 5tm + resolutions." Thesis, 2014. http://hdl.handle.net/1805/3911.

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Stamps, Lucas G. "A Laminated Carbonate Record of Late Holocene Precipitation from Martin Lake, LaGrange County, Indiana." Thesis, 2016. http://hdl.handle.net/1805/10030.

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Indiana University-Purdue University Indianapolis (IUPUI)
Precipitation trends and their driving mechanisms are examined over a variety of spatial and temporal scales using a multi-proxy, decadally-resolved sediment record from Martin Lake that spans the last 2300 years. This unique archive from a northern Indiana kettle lake documents significant climate variability during the last 2 millennia and shows that the Midwest has experienced a wide range of precipitation regimes in the late Holocene. Three independent proxies (i.e., oxygen and carbon isotopes of authigenic carbonate and %lithics) record variations in synoptic, in-lake and watershed processes related to hydroclimate forcing, respectively. Together, these proxies reveal enhanced summer conditions, with a long period of water column stratification and enhanced summer rainfall from 450 to 1200 CE, a period of time that includes the so-called Medieval Climate Anomaly (950-1300 CE). During the Little Ice Age, from 1260 to 1800 CE, the three proxy records all indicate drought, with decreased summer rainfall and storm events along with decreased lake stratification. The Martin Lake multi-proxy record tracks other Midwest climate records that record water table levels and is out-of-phase with hydroclimate records of warm season precipitation from the High Plains and western United States. This reveals a potential warm season precipitation dipole between the Midwest and western United States that accounts for the spatial pattern of late Holocene drought variability (i.e., when the Midwest is dry, the High Plains and the western United States are wet, and vice versa). The spatiotemporal patterns of late Holocene North American droughts are consistent with hydroclimate anomalies associated with mean state changes in the Pacific North American teleconnection (PNA). Close associations between late Holocene North American hydroclimate and records of Northern Hemisphere temperatures and the Pacific Ocean-atmosphere system suggests a mechanistic linkage between these components of the global climate system that is in line with observational data and climate models. Based on our results, predominantly –PNA conditions and enhanced Midwestern summer precipitation events are likely to result from continued warming of the climate system. In the western United States, current drought conditions could represent the new mean hydroclimate state.

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28

Chipfupa, Lukas. "The effects of weather variability on growth potential of Afrikaner cattle in a semi-arid region in Zimbabwe." Diss., 2012. http://hdl.handle.net/10500/10198.

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Only part of the abstract could be included due to the rest having renderable text
The abiotic environment plays an important role in cattle production. Key abiotic elements evaluated in this study are rainfall and temperature. This study was carried out to assess the effect and contribution of rainfall and temperature, amid other factors, on pre- and post-weaning growth traits of Afrikaner cattle at Matopos Research Institute from 1958 to 1997. Historical data generated from a genotype x environment interaction study at Matopos Research Institute was used to identify factors associated with the average daily weight gain of calves of Afrikaner cattle breed. A total of 10 700 records were retrieved comprising of birth weight (BW), 90 day weight, 205 day weight and early post-weaning weight as well as additional corresponding rainfall and temperature data from 1958 to 1997. The rainfall and temperature data was computed asrainfall and temperature variability. The data was corrected for heteroscedasticity using the generalized least squares approach (GLS) before running an ordinary least square regression (OLS) analysis to determine the association between growth rate and potential explanatory factors for average daily weight gain, pre-weaning weight gain and early post-weaning weight gain.
Agriculture and Animal Health
M. Sc. (Agriculture)

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29

Compton, Andrea Jean. "The correlation of sea surface temperatures, sea level pressure and vertical wind shear with ten tropical cyclones between 1981-2010." Thesis, 2013. http://hdl.handle.net/1805/3669.

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30

Beerval, Ravichandra Kavya Urs. "Spatiotemporal analysis of extreme heat events in Indianapolis and Philadelphia for the years 2010 and 2011." Thesis, 2014. http://hdl.handle.net/1805/4083.

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Indiana University-Purdue University Indianapolis (IUPUI)
Over the past two decades, northern parts of the United States have experienced extreme heat conditions. Some of the notable heat wave impacts have occurred in Chicago in 1995 with over 600 reported deaths and in Philadelphia in 1993 with over 180 reported deaths. The distribution of extreme heat events in Indianapolis has varied since the year 2000. The Urban Heat Island effect has caused the temperatures to rise unusually high during the summer months. Although the number of reported deaths in Indianapolis is smaller when compared to Chicago and Philadelphia, the heat wave in the year 2010 affected primarily the vulnerable population comprised of the elderly and the lower socio-economic groups. Studying the spatial distribution of high temperatures in the vulnerable areas helps determine not only the extent of the heat affected areas, but also to devise strategies and methods to plan, mitigate, and tackle extreme heat. In addition, examining spatial patterns of vulnerability can aid in development of a heat warning system to alert the populations at risk during extreme heat events. This study focuses on the qualitative and quantitative methods used to measure extreme heat events. Land surface temperatures obtained from the Landsat TM images provide useful means by which the spatial distribution of temperatures can be studied in relation to the temporal changes and socioeconomic vulnerability. The percentile method used, helps to determine the vulnerable areas and their extents. The maximum temperatures measured using LST conversion of the original digital number values of the Landsat TM images is reliable in terms of identifying the heat-affected regions.

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Elimi, Ibrahim O. "An estimate of carbon footprint of Ekurhuleni Health District office and provincial clinic employees." Diss., 2017. http://hdl.handle.net/10500/23723.

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Climate change is regarded as the greatest threat facing the world today. The Intergovernmental Panel on Climate Change (IPCC) concluded that climate change is caused by human activities, as a result of greenhouse gases (GHGs) being emitted into the atmosphere. Scientific literature on the impact of climate change is well documented, especially for the health sector. The mission of the Gauteng Department of Health (GDoH) is to “contribute towards the reduction of the burden of diseases in all the communities in Gauteng”. Ekurhuleni Health District is part of GDoH and shares a similar mission. However, this mission is under threat due to the direct and indirect impact of climate change on the public health sector. Therefore, it is essential for Ekurhuleni Health District and Provincial Clinics to take measures to reduce their contribution to climate change in the light of improving the health of their constituent. This study estimates the carbon footprint of the employees of Ekurhuleni Health District and Provincial Clinics and determines the knowledge and perception of climate change among managers and operational employees. The methodologies of the Greenhouse Gas Protocol (GHGP) and the Department of Environmental Forestry and Rural Affairs (DEFRA) were used to quantify the carbon footprints of the employees of the Ekurhuleni Health District and Provincial Clinics. A content analysis was applied to determine the knowledge and perception of climate change. The study revealed that Scope 2, indirect emissions (electricity), accounts for 92% (35150 t CO2e) of the total carbon footprints for the period of five years, 2010-2014. Scope 1, direct emission (vehicles), is responsible for 4% (1362 t CO2e) and Scope 3, indirect emissions for ICT, for 2% (862 t CO2e), office paper 1% (181 t CO2e) and air conditioners 1% (458 t CO2e). The majority of employees demonstrated basic knowledge of climate change. However, the concept of GHGs was unfamiliar to most of the employees. In terms of perceptions of climate change, the majority of employees were concerned about the future of the planet and climate change and believed that climate change will impact their job description. The study recommends the following mitigation measures, among others, to reduce carbon footprints: (1) electrical vehicles; (2) substituting personal desktops with laptops; and (3) substituting HFC-23 air conditioner refrigerant with R410A. These recommendations have the potential to reduce the carbon emissions by 2445 t CO2e for the period of five (5) years and save R7 875 089 from fuel and power consumption. Furthermore, the District Office and Provincial Clinics can generate a revenue of R293 400 by registering for a CMD project for five years or R1 173 600 for the duration of the project (20 years).
Environmental Sciences
M. Sc. (Environmental Management)

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32

Porter, Raymond E. "Public perception and response to extreme heat events." Thesis, 2014. http://hdl.handle.net/1805/3802.

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Indiana University-Purdue University Indianapolis (IUPUI)
In the United States extreme heat events have grown in size and stature over the past 20 years. Urban Heat Islands exacerbate these extreme heat events leaving a sizable portion of people at risk for heat related fatalities. The evidence of this is seen in the Chicago heat wave of 1995 which killed 500 people over the course of a week and the European heat wave of 2003 which killed 7,000 people in the course of a month. The main guiding questions then become how government and the media can most effectively warn people about the occurrence of extreme heat events? Should extreme heat warnings be issued by T.V., newspaper or by radio? Even if warnings are issued will the population at large still change their behavior? Another possible question is whether people most vulnerable to extreme heat will change their behavior? A survey in 2010 by NASA will be the main basis for this analysis. This survey set out to see how well people in Phoenix, Philadelphia, and Dayton responded to extreme heat alerts by changing their behavior.

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Chapungu, Lazarus. "Impact of climate change on vegetative species diversity in Masvingo Province, Zimbabwe." Thesis, 2017. http://hdl.handle.net/10500/23781.

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Vegetative species diversity is under threat from environmental pressures, particularly climate change. As the impacts of climate change vary from place to place, response of vegetative species diversity to a changing climate also vary depending on geographical location. The response of vegetative species diversity under dry conditions in Zimbabwe is not well known. This study assessed the impact of climate change on vegetative species diversity under semiarid conditions of Masvingo province in Zimbabwe. This was achieved by determining climate change trends over a period of forty years (1974-2014), and examining the relationship between vegetative species diversity and spatially interpolated climate data. The absence of historical diversity data prompted the use of remote sensing to enable the assessment of spatial and temporal changes. Thus, the Normalised difference vegetation index (NDVI) was used to assess vegetative species diversity changes after establishing a positive relationship between species diversity and NDVI. The mixed methods research design was used as the strategy of inquiry. The non-aligned block sampling design was used as the sampling framework from which 198 sampling points were identified. Meteorological data obtained from Zimbabwe Meteorological Services Department (ZMSD) and the National Climate Data Centre (NCDC) were used for climate change analysis. Data collected through image analysis, direct observations, questionnaire surveys and interviews were used to assess the impact of climate change on vegetative species diversity. Results indicate that all temperature and precipitation variables have significant (p<0.05) trends over the period under study. However, the trend for seasonal total precipitation was not significant but declining. The significant trends indicate that climate change occurred over the period under study. 93% of the respondents confirmed having experienced the climate change phenomenon. Results also show a significant relationship between climate elements (precipitation and temperature) and vegetative species diversity represented by Shannon Weaver Index (H). More so, there is a positive relationship between NDVI and H. Vegetative species diversity represented by NDVI decreased over the period under review. The results indicate that climate change has contributed to the decrease of vegetative species diversity in Masvingo province, thus it is a force behind many other factors contributing to biodiversity loss.
College of Agriculture and Environmental Sciences
Ph. D. (Environmental Sciences)

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Dissertations / Theses on the topic 'Climatic changes Research Indonesia'

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