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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Maintenance of the global temperature field as deduced from assimilations by a global circulation model

Schubert, Siegfried Dieter. January 1980 (has links)
Thesis (M.S.)--University of Wisconsin--Madison. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 102-105).
2

A case study of height and temperature analyses derived from Nimbus-6 satellite soundings of a fine mesh model grid

Koehler, Thomas Lee, January 1979 (has links)
Thesis--University of Wisconsin--Madison. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 183-186).
3

Temperature variability and change at various altitudes across Lesotho and adjoining areas: implications for agriculture

Nhlapo, Linah Adelina January 2017 (has links)
A research report submitted to the Faculty of Science, University of the Witwatersrand, in partial fulfillment of the requirements for the degree of Master of Science. Johannesburg, 2017. / Lesotho, being a mountainous area and due to the level of poverty and the dependency of its economy largely on agriculture, is particularly vulnerable to the impacts of climate change. This study examined maximum, minimum and mean temperature trends at various altitudes in Lesotho so as to determine possible implications of recent (70 - 80 years) altitudinal climate trends on the agricultural sector. Using seven stations at various altitudes across Lesotho, trends in maximum, minimum and mean temperatures were analyzed at monthly, annual and seasonal scales. The significant warming of minimum temperatures (Mokhotlong (p=0.000), Oxbow (p=0.013) and Qachasnek (p=0.002)) and maximum temperatures (Mokhotlong (p<0.0001), Oxbow (p=0.007) and Qachasnek (p=0.000)), were observed at the highland stations, located on the eastern side of Lesotho, while at the lowland stations as well as in the foothills, located on the western side of Lesotho, significant increases were only observed with minimum temperatures (Maseru (p<0.0001) and Mejametalana (p=0.000), Butha Buthe (p=0.017), located on the western side of Lesotho. In Mohaleshoek, located in the Senqu river valley, no significant trends were observed. In addition, a significant decrease in the number of days with frost was observed in both the highlands and the lowlands. With significant increases in maximum and minimum temperatures, a decline in agricultural production can be expected in the lowlands while a potential increase in areas suitable for agricultural production can be expected in the highlands. / LG2017
4

Will Ultrasound Performed with the Rich-Mar AutoSound™ Be as Effective at Increasing Tissue Temperature as Ultrasound Performed with a Traditional Machine?

Black, Heather Diane 01 June 2015 (has links)
STUDY DESIGN: Randomized crossover experiment. OBJECTIVE: To determine whether the Rich-Mar AutoSound™ would be as effective as traditional ultrasound at increasing the temperature of the triceps surae muscle during a 10-min, 1 MHz, 1.0 W/cm2 ultrasound treatment. BACKGROUND: The AutoSound™ is a hands-free ultrasound device that is strapped on the body and left for the duration of the ultrasound treatment. It requires no clinician during the actual ultrasound treatment, thus freeing the clinician to perform other tasks and reducing clinician error during treatments. METHODS: 16 healthy subjects (6 males, 10 females, age = 22 ± 1.6 yrs, height = 173.2 ± 8.4 cm, weight = 72.5 ± 11.3 kg, triceps surae subcutaneous fat thickness = 0.85 ± 0.37 cm) received a 10-min, 1 MHz, 1.0 W/cm2 ultrasound treatment over their left triceps surae muscle with both the AutoSound™ and traditional ultrasound (via the TheraHammer™) with 24 hours between treatments. Temperatures were measured every 30 seconds during the ultrasound treatments by way of a thermistor, approximately 2.25 cm deep in the triceps surae. RESULTS: The AutoSound™ was not effective at increasing the temperature of the triceps surae muscle, as temperature decreased 0.16°C during treatment (p = 0.334). On average, the AutoSound™ caused intramuscular temperature to decrease at a rate of 0.016 ± 0.001°C per min. Traditional ultrasound performed using the TheraHammer™ had a total temperature increase of 0.41°C. Rate of temperature increase during traditional ultrasound was 0.025 ± 0.003°C per min (p < 0.0001). CONCLUSION: The AutoSound™ is not as effective at increasing muscle temperature as traditional ultrasound during a 10-min, 1 MHz, 1.0 W/cm2 treatment. However, neither the AutoSound™ nor traditional ultrasound was very effective at increasing the temperature of the triceps surae muscle during the treatment time.
5

The GCRC two-dimensional zonally averaged statistical dynamical climate model : development, model performance, and climate sensitivity /

MacKay, Robert Malcolm, January 1994 (has links)
Thesis (Ph. D.), Oregon Graduate Institute of Science & Technology, 1994.
6

Simulation of climate-sedimentary evolution a comparison of climate model results to the geologic record for India and Australia /

Fawcett, Peter J. January 1994 (has links)
Thesis (Ph. D.)--Pennsylvania State University, 1994. / Vita. Includes bibliographical references.
7

Ecological genetics of populations experiencing changing environmental conditions

Husby, Arild January 2010 (has links)
A major goal in evolutionary biology is to understand how ecological factors shape the phenotypic and genetic variation that we observe in natural populations and in this thesis I examine how rapid changes in temperature have influenced phenotypic and genetic variation in morphological and life history traits in long-term studies of great tits. In Chapter 1 I review what is known about the effects of environmental change on natural populations, and outline the quantitative genetic framework that is available to study genetic variation in natural populations. Much focus on the effects of climate change has concerned species’ phenology, far less attention has been given to other traits. In Chapter 2 I examine the effects changing environmental conditions have had on the proportion of females that produce second broods. Temperature operates mainly through indirect effects (such as food abundance) but may also have more direct effects. In Chapter 3 I show that over a 36 year period body size have declined in line with predictions from Bergmann’s rule and I explore the genetic basis of this decline and the environmental factors involved. Although we can learn much from population level responses, there is a great deal of additional information to be gained by studying between-individual responses. In Chapter 4 I therefore compare the multivariate pattern of between-individual variation in phenotypic plasticity and its genetic basis for laying date and clutch size, in two great tit populations. Environmental changes may also directly affect the expression of genetic variance as well as the strength of selection acting on a trait, and in Chapter 5 I show that, for laying date, the environment induces a positive covariance between strength of selection and the expression of additive genetic variance, something that may enhance the rate of adaptation. Finally, in Chapter 6 I discuss and summarise the wider implications of the findings from this thesis.
8

How is climate change incorporated into environmental impact assessments (EIAs) in South Africa?

Aljareo, Abdulhakim 30 January 2015 (has links)
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 by Coursework and Research Report. Johannesburg 2014. / Climate change is an issue of global significance resulting in trans-boundary environmental and socio-economic impacts. South Africa is involved in the international efforts to address climate change, has accepted the findings of the Intergovernmental Panel on Climate Change (IPCC) Assessment Report and developed a National Climate Change Response Policy, listing the impacts of climate change on the sustainable development in South Africa. The main causes of climate change are Greenhouse Gases (GHGs), which have been emitted from different development activities over temporal and spatial scales. In order to reduce the emissions of GHGs and protect proposed development projects from climate change impacts, climate change mitigation and adaptation measures should be incorporated into Environmental Impact Assessment (EIA). This research aimed to describe climate change incorporation into the EIA legal regime and practice in South Africa, based on climate change impacts on sustainable development and the role of EIA in considering climate change. The methodology involved reviewing EIA regulations and related legislation, EIA case studies from Gauteng province conducted between 2010 and 2013, key informant interviews with Environmental Assessment Practitioners (EAPs), and discussion on the linkedin group of the International Association for Impact Assessment of South Africa (IAIAsa). The study concluded that climate change is not explicitly incorporated into the EIA regime, but it is implied in the EIA regulations and related legislation. Largely as a result of the lack of climate change incorporation in the EIA legal regime, climate change is not adequately considered in the EIA practice. In order to support the contribution of EIA to sustainable development in South Africa, It is recommended that climate change should be incorporated into EIA regulations in the next amendment of NEMA. This can be done through including listed activities that require climate change incorporation into the EIA based on type of an activity and/or specific receiving environments. It is also suggested that EIA guidelines for climate change consideration be developed. Further recommendations include supporting the role that Strategic Environmental Assessment (SEA) and Environmental Management Framework (EMF) play, in conjunction with the EIA, in considering climate change; increasing the availability of accurate, local climate change data and modelling technology; developing staff capacity and awareness about climate change, and building EAP’s ability to incorporate climate change in the EIA through the support of government related authorities and associations such as IAIAsa and EAPSA. Key words: climate change, EIA, mitigation, adaptation, EIA legal regime, EIA practice.
9

Application of Phase Change Materials to Improve the Thermal Performance of Buildings and Pavements

Pourakbar Sharifi, Naser 11 January 2017 (has links)
In recent decades, much research has investigated the efficiency of Phase Change Materials (PCMs) in improving the thermal performance of buildings and pavements. In buildings, increasing the thermal inertia of structural elements by incorporating PCMs decreases the energy required to keep the inside temperature in the comfort range. In concrete pavements, using PCMs decreases the number of freeze/thaw cycles experienced by the pavement and thus increases service life. However, PCMs cannot be added to cementitious binders directly, because they interfere with the hydration reactions between cement and water that produce strength-bearing phases. Therefore different carriers have been proposed to indirectly incorporate PCMs in cementitious materials. Lightweight Aggregate (LWA) is one of the materials that has been proposed as PCM carrier agent. However, it was not studied in depth before. Various experiments were conducted to investigate the problems associated with incorporating LWA presoaked in PCM in cementitious media. The results show that a portion of PCM leaks out of the LWA’s structure and subsequently affects different chemical, physical, and mechanical properties of the binder. In addition, the applicability of Rice Husk Ash (RHA), a common material never before used to encapsulate PCM, as a PCM carrier agent was investigated. The results show that RHA can absorb and contain liquids in its porous structure; and regarding its compatibility with the cementitious media, it can be used as PCM carrier. Different computational simulations using Typical Meteorological Year data were conducted to evaluate the efficiency of PCMs in improving the thermal performance of buildings. Utilizing PCM-incorporated gypsum boards was shown to be a promising strategy to achieve the governmental plans of “Zero Net Energy� buildings. The results show that using a PCM with a melting point near the occupant comfort zone delays and reduces the inside peak temperature, increases the duration of time during which the inside temperature stays in the comfort zone, and decreases the cost and energy required by HVAC system to keep the inside temperature in this range. However, PCMs’ efficiency is completely dependent on the input temperature profile.
10

The sublime of climate change

Gallie, Nicholas January 2018 (has links)
The category 'sublime', when applied to the natural world, has long been associated in Western culture, with extremes of vastness and power. When encountered, that which is deemed sublime, by virtue of these qualities, has the effect of overwhelming the mind, such that it is thrown simultaneously into a state of astonishment, admiration and horror. We are both humbled and elevated by what we behold and momentarily struck dumb, such that, in its Kantian formulation, our appreciation of that which we take to be sublime, granted us through the powers of reason, has the effect of ennobling us, as moral beings. The concept of the sublime has continuously evolved from its classical origins right up to its present day post-modern formulations. The diversity of its forms suggests that the sublime can be regarded as polythetic. My thesis examines, how, through its different formulations, the sublime may be meaningfully applied to our perceptions of present day climate change, and the different implications arising from these applications. My thesis asks: what is the sublime of climate change? When we look at climate change through the lens of the sublime, what do we see, and what is obscured? What is the effect on us, of opening ourselves to climate change as sublime? What implications might the sublime of climate change have for the future direction of society and therefore for the construction of climate policy and for its communication? Original research, in the form of in-depth, unstructured, one to one interviews was conducted among senior climate scientists, business leaders and policy makers, writers and academics, inviting them to explore the theme of climate change, science and the sublime. My thesis findings are derived from my analysis of these discussions.

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