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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.

A critical investigation into the barriers and opportunities for environmental management systems 'EMSs' implementation for the delivery of environmental benefits to the Industrial City in Jeddah, KSA

Alsiary, Waleed January 2015 (has links)
The first Industrial City (IC) in Saudi Arabia was established in Jeddah; it is now suffering from serious environmental problems. Environmental Management Systems (EMSs) represent an internationally recognised tool developed to provide a systematic, self-monitoring approach for making continual improvements to all the environmental aspects of a business in line with local environmental regulations and standards. This research critically investigates the scope of the implementation of EMSs in this IC, which necessarily entails assessing the efforts of the Presidency of Meteorology and Environment (PME), which is the government agency responsible for environmental protection. This research also details the barriers and possible environmental benefits to be derived from EMS implementation. These objectives are achieved through a multi-method case study research design, involving questionnaires, semi-structured interviews and document analysis. 183 organizations (32% of all organizations in the IC) participated in the questionnaires, and two sets of interviews were conducted: 14 with environmental managers in the IC, and 12 with officials from various relevant government agencies. The results show that the basic requirements of EMS are inadequately implemented, and that awareness of environmental legislation (and compliance with it) is extremely limited. The most important barriers facing the implementation of EMSs in this IC include lack of enforcement of existing legislation and low levels of environmental awareness. The cost of implementing EMSs is a further important obstacle, particularly for small- and medium-sized organizations (SMEs). Nevertheless, although the main motivations reported were economic, adopting an EMS in full can result in measurably improved environmental performance, through reducing natural resource consumption (chiefly energy and water). Those with an informal or partial EMS also experience environmental benefits relative to those who have no form of EMS. Improvements to operational safety are another benefit to be derived from implementing EMSs. It also argues that the widespread adoption of EMS could greatly assist the government in its drive toward sustainable development and improved management of natural resources. Accordingly, recommendations are provided to enhance the implementation of EMS in the IC as well as to overcome the aforementioned obstacles in order to effect changes towards achieving sustainable development. Keywords: Environmental management systems (EMSs); implementation of EMS; Sustainable development; Environmental awareness; EMSs; KSA.

How does plankton distribution and activity influence the variability of carbon dioxide uptake in the North Atlantic?

Ostle, Clare January 2015 (has links)
This study combines two invaluable datasets that have been collected on-board volunteer observing ships to analyse the variability of the carbon dioxide (CO2) sink in the North Atlantic at a range of spatial and temporal scales. Phytoplankton indices collected from the continuous plankton recorder (CPR) and the concentration of CO2 within the surface waters show that at seasonal time-scales phytoplankton play an important role in maintaining the carbon drawdown within the northeast Atlantic, while sea surface temperature (SST) drives the seasonal signal in CO2 flux in the subtropics. The North Atlantic remained a significant sink of CO2 between 2002 and 2013, despite strong inter-annual variability in CO2 flux that was correlated to changes in the North Atlantic Oscillation and the influence that this had on SST. Discrete dissolved inorganic carbon, total alkalinity and dissolved oxygen samples were collected during 4 voyages between April 2012 and February 2013. Using these measurements this study successfully developed and implemented a simple and inexpensive technique to estimate net community production in the surface ocean, with the potential to extend coverage of such measurements over wider regions at low cost. Two key observations were made in the northeast Atlantic. Firstly, the increase in SST was significantly correlated with the increase in phytoplankton colour index measured by the CPR between 1960 and 2012, despite other micro and nanophytoplankton counts decreasing over this time frame. This suggests that as the surface ocean warms and stratification is enhanced, pico-phytoplankton (which contribute to the colour index but not the phytoplankton counts) may be better equipped to dominate the system, compared to larger species that are more nutrient dependent. Secondly, the CO2 uptake capacity has decreased compared to the 1990s. Combined, these two results will likely have a significant impact on carbon flux, export efficiency and ecosystem dynamics.

Drivers of population cycles in ecological systems

Reynolds, Jennifer Joan Heather January 2012 (has links)
In this thesis, mathematical models are used to investigate potential drivers of population cycles. Population cycles are a common ecological phenomenon, yet the mechanisms underpinning these oscillations are not always known. We focus on two distinct systems, and evaluate potential causes of cyclic dynamics. In the first part of the thesis, we develop and analyse a host–pathogen model, incorporating density-dependent prophylaxis (DDP). DDP describes when individuals invest more in immunity at high population densities, due to the increased risk of becoming infected by a pathogen. The implications of this for the population dynamics of both host and pathogen are examined. We find that the delay in the onset of DDP is critical in determining whether DDP increases or decreases the likelihood of population cycles. Secondly, we focus on a particular cyclic vole population, that of Kielder Forest, Northern UK. We construct a model to test the hypothesis that the population oscillations observed in this location are caused by the interaction between the voles and the silica in the grass they consume. We extend our model by including seasonal forcing, and study the effects of this on the population dynamics.

Iodine in sea ice and the polar atmosphere

Atkinson, Helen January 2011 (has links)
The volatilisation of iodine from the ocean and release to the atmosphere in the ice-covered polar regions has been studied. Laboratory experiments involving sea ice- and ice associated- diatoms have shown how the extreme conditions experienced in sea ice brine channels may lead to an increase in production of organic forms of iodine. Trends were observed in production by different classes of enzymes, active in the oxidative metabolism of the cell. An enhancement in trace gas concentrations due to the concentration effect of solvent volume reduction has also been demonstrated. Field campaigns have been undertaken in both the Arctic and Antarctic. Ship-based measurements in the Weddell Sea have implicated I2 as a key species in the mechanism of enhancement of atmospheric iodine in this region. Organic and inorganic forms of iodine were measured in seawater, sea ice and the atmosphere. On the Brunt ice shelf, enhanced concentrations of CH3I and C2H5I were measured in the snow firn air, with a diurnal profile, suggesting the snow may be a source of these compounds. These measurements have implications for atmospheric mixing ratios of IO, measured from the ship and validated by satellite data, and new particle formation. This is the first combined in situ study in Antarctica of organic and inorganic iodine compounds in sea water, ice and air. On the Western Antarctic Peninsula, IO was detected in the atmosphere, and seawater measurements of iodocarbons have demonstrated how organic compounds of iodine are enhanced during the phytoplankton bloom; these measurements are also a first. Iodine emissions in the sea ice zone were also quantified in two campaigns in the Arctic environment. High concentrations of halocarbons were measured in the brine of sea ice, with respect to the water below, in the Arctic Ocean. High atmospheric halocarbon mixing ratios and flux calculations have demonstrated the effect on the atmosphere above. In the Canadian sub-Arctic, where the ice had quite different physical properties, halocarbon concentrations were the highest ever recorded for some compounds, due to extreme concentration in very cold ice. The enhancement of organic forms of iodine in sea ice has therefore been demonstrated. I2 has been implicated as a key species in iodine emissions. Therefore, understanding has been furthered on the chemistry of iodine in sea ice and polar atmosphere.

Polar föhn winds and warming over the Larsen C Ice Shelf, Antarctica

Elvidge, Andrew January 2013 (has links)
Recent hypotheses that the foehn effect is partly responsible for warming to the east of the Antarctic Peninsula (AP) and enhanced melt rates on the Larsen C Ice Shelf are supported in a study combining the analysis of observational and high resolution model data. Leeside warming and drying during foehn events is observed in new aircraft, radiosonde and automatic weather station data and simulated by the UK Met Office Unified Model at ~1.5 km grid spacing (MetUM 1.5 km). Three contrasting cases are investigated. In Case A relatively weak southwesterly flow induces a nonlinear foehn event. Strongly accelerated flow above and a hydraulic jump immediately downwind of the lee slopes lead to high amplitude warming in the immediate lee of the AP, downwind of which the warming effect diminishes rapidly due to the upward ‘rebound’ of the foehn flow. Case C defines a relatively linear case associated with strong northwesterly winds. The lack of a hydraulic jump enables foehn flow to flood across the entire ice shelf at low levels. Melt rates are high due to a combination of large radiative heat flux, due to dry, clear leeside conditions, and sensible heat flux downward from the warm, well-mixed foehn flow. Climatological work suggests that such strong northwesterly cases are often responsible for high Larsen C melt rates. Case B describes a weak, relatively non-linear foehn event associated with insignificant daytime melt rates. Previously unknown jets – named polar foehn jets – emanating from the mouths of leeside inlets are identified as a type of gap flow. They are cool and moist relative to adjacent calmer regions, due to lower-altitude upwind source regions, and are characterised by larger turbulent heat fluxes both within the air column and at the surface. The relative importance of the three mechanisms deemed to induce leeside foehn warming (isentropic drawdown, latent heating and sensible heating) are quantified using a novel method analysing back trajectories and MetUM 1.5 km model output. It is shown that, depending on the linearity of the flow regime and the humidity of the air mass, each mechanism can dominate. This implies that there is no dominant foehn warming mechanism, contrary to the conclusions of previous work.

Organising science policy : participation, learning & experimentation in British democracy

Pallett, Helen January 2014 (has links)
The incorporation of public participation into science policy processes has been an important feature of policy practice and the academic literature for more than two decades, yet it has failed to realise its democratising potential or to engender broader changes in organisational and political cultures. To understand this apparent paradox this thesis focuses on organisational changes and practices around public participation, thus transcending the conventional focus on individual participation processes which characterises much academic work on the topic. Given the apparent lack of learning from and about public participation in key science policy organisations, this thesis explores diverse processes and facets of organisational learning, reflection and reflexivity in and around Sciencewise, a UK Government-funded body, which is emblematic of emerging professionalised organisations of participation. Drawing upon ethnographic and qualitative methods within a co-productionist idiom (Jasanoff 2004a), the thesis tells a number of stories about Sciencewise’s organisational learning processes during 2013; some are localised and specific, others identify more coherent shifts, and others draw connections between Sciencewise and broader political events. Diverse facets of organisational learning are explored from themes of spatiality, formal organisational mechanisms and organisational memory to non-knowledge, future imaginaries and processes of experimentation. It is argued that organisational learning cannot be understood without attention to the minutiae of everyday meetings and communications systems, or to broader political shifts like civil service reform. Despite the apparent rigidity of Sciencewise practices and discourses, there were significant instances of learning and change observed, resulting in shifting organisational categories, understandings and practices. These represent examples of more reflective and reflexive capacities within the programme. The thesis makes significant conceptual contributions to understandings of organisational learning, contributes empirical insights into the institutionalisation of participation in UK policy practice, and offers practical insights into the challenge of conducting engaged research and encouraging organisational reflexivity.

Föhn winds on South Georgia and their impact on regional climate

Bannister, Daniel January 2015 (has links)
South Georgia is a small and mountainous island, located in the remote Southern Ocean. The island’s subantarctic climate is controlled by its location and steep orography; with 19 peaks over 2000m and situated within a belt of strong westerly winds South Georgia acts as an effective barrier to the winds that impinge upon it. Since the 1920s, average summer temperatures have risen by ~1oC on South Georgia. Coupled with this has been an increase in the rate of glacial retreat throughout the last century, with glaciers on the northeast leeside of the island retreating at a faster rate than those on the southwest side. These asymmetrical changes are thought to be linked with the strengthening of the westerlies. If the strength of the westerlies is sufficient, downslope winds can develop on the leeside of the island causing significant temperature increases as the descending air warms adiabatically; this is known as the föhn effect. Therefore, the aim of this thesis is to investigate whether the observed asymmetric pattern of regional warming and glacier retreat are caused by the föhn warming process. To explore the link between the föhn effect and its impact on the regional climate of South Georgia, a 10 year climatology (2003 – 2012) of föhn events is created. Using automatic weather station observations to identify abrupt changes in temperature, humidity and wind speed, it is found that föhn events are frequently observed (874 events are identified in total) with one event occurring every four days. Following this, sensitivity simulations with the Weather Research and Forecasting model for four föhn cases studies are presented, with the aim of deducing the optimal model setup for South Georgia. The model analysis is largely supported by observations, and föhn flow is well captured at high (< 3.3km) horizontal resolution. With the model optimised for South Georgia, a 21 month model run (at 0.9km resolution) produces the first ever detailed regional climatology of South Georgia. The results from this simulation illustrate the asymmetrical impact of föhn on the island’s climate. During September 2011 – August 2012, modelled föhn events produced +2oC air temperature anomalies and up to 3m water equivalent ablation at the termini of South Georgia’s north-eastern glaciers. This supports the view that föhn is partly responsible for the asymmetrical retreat of glaciers, via enhanced leeside surface warming and melting. These results support the original hypothesis that an enhancement of the föhn warming process could have implications on future asymmetrical warming and melt.

Trace gases in Antarctic and Greenland firn and ice : a record of carbonyl sulphide and the isotopologues of chlorofluorocarbons

Allin, Samuel January 2015 (has links)
Through the industrial revolution of the last 250 years, trace gases have had a significant impact on the climate. Of particular relevance to this work are species which facilitate the destruction of stratospheric ozone. In this thesis, I focus on four of these species. Understanding the release, reaction and transport pathways of the man-made chlorofluorocarbons (CFCs) could help us to mitigate their destructive effect. Previous studies have found that both source and sink processes significantly alter the isotopic composition of trace gases (e.g. N2O and CFC-12). Measuring these changes can be used to better constrain the interaction of these gases with the atmosphere. Atmospheric histories of δ(37Cl) and δ(13C) in CFC-11, CFC-12 and CFC-113 are presented, covering the last 20 – 60 years. Air samples came from Greenland (NEEM) and Antarctic (Fletcher Promontory) polar firn, with additional samples taken from an archive of Southern Hemispheric background air (Cape Grim, Tasmania). This study extends the novel approach to measuring trace gas isotope ratios in small air volumes (200 – 600 ml), using a single-collector gas chromatography-mass spectrometry system. Carbonyl sulphide (COS) is the principal source of sulphur in the stratosphere, where it breaks down into sulphate aerosol which catalyses the destruction of ozone. Air was extracted from Greenland (NEEM) and Antarctic (DE08, DML (BAS) and DSS) ice core samples and analysed for COS and a range of other trace gas mole fractions. The COS measurements were affected by a previously unknown post-extraction growth effect, leading to higher than expected values. This study also presents new COS measurements in firn air from NEEM and the Southern Hemisphere (EDML, Antarctica). The observed increase and subsequent decrease largely reflects changes in anthropogenic emissions during the 20th century. These measurements also indicate that regional and site-specific effects have a significant influence on the recorded atmospheric history of COS.

Interactions between community traditions and geospatial technology in natural resource management : case studies from common property regimes in rural southern Mexico

Canto Vergara, Jose January 2015 (has links)
Issues related to improving community participation and the effectiveness of green economy instruments are central to current debates regarding progress towards sustainable development. Information technology, such as Geographic Information Systems, may be able to play an important role in addressing these challenges. In this study an experiment with introducing geospatial technology was conducted with four rural communities at different levels of engagement with institutional frameworks of payments for ecosystem services in Chiapas, Mexico. The purpose was to examine the impacts of such an intervention and evaluate whether it had the potential to enhance collective understanding of natural resource management practices, lead to better shared decisions and enhance community social capital. By exploring the outcomes it was also possible to assess the conditions that enable or constrain such implementation processes. Five key themes (i.e. social structure, IT skills, participation in development, external relations and power structures) were identified in an evaluation framework informed by actor-network theory concepts, and these guided the collection of evidence and data analysis. The results indicated that all of these factors had some influence over the success of geospatial technology analysis transfer, with community political decisionmaking processes and previous involvement of external agents in local natural resource management activities being of particular importance.

Applications of quantitative methods in environmental economics : econometrics, simulation modelling and experiments

Smith, Gregory Steven January 2016 (has links)
In Part I of this thesis we employ novel econometric techniques to explore elicitation anomalies in contingent valuation (CV). According to standard assumptions regarding preferences, changes in the way values are elicited in CV questions should be decision irrelevant. That responses are observed to systematically differ according to elicitation format has, therefore, called the CV method into question. One possible explanation lies in the proposition that respondents are uncertain about their preferences and that their uncertainty precipitates systematically different responses to different question formats. We test this hypothesis using data from a split-sample CV survey. We analyse our data using an innovative application of a semi-parametric estimator more commonly used for duration modelling in the medical sciences but find that uncertainty alone cannot explain away common elicitation anomalies. In Part II we employ simulation modelling and experimental techniques to investigate payment for ecosystem services (PES) schemes that involve multiple buyers. In Chapter 2, we explore opportunities for buyers in PES scheme to realise Paretoimproving outcomes through spatial coordination in their independent purchases of changes to land-management practices. We develop a simulation environment imitating a heterogeneous agricultural landscape and using techniques of integer-linear programming solve for outcomes under different institutional arrangements. Our simulations allow us to explore how gains from negotiated or fully-cooperative purchasing differ across different configurations of landscape and buyer objectives. In Chapter 3, we investigate negotiation as a multiple-purchaser ecosystem service procurement mechanism. We design and conduct novel three-person bargaining experiments in which two potential buyers can negotiate not only between each other but also with a seller of ecosystem services. We find that negotiated deals can be reached that are mutually advantageous to all parties. In all treatment scenarios presented, the vast majority of groups are able to reach agreements; in addition, these agreements are reached relatively quickly.

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