A computer simulated model representing carbon dynamics within the eastern equatorial Pacific was developed. The three compartment model incorporated the physical, biological and chemical processes most significant to the region of study representing both "normal" and highly disruptive conditions. The events which interrupt the normal carbon dynamics are known as El Niño events. The most profound effects that the El Niño has on the eastern equatorial Pacific are anomalously high sea-surface temperatures and a weakening in the typically intense upwelling motion. It is during these periods that the equatorial Pacific has been thought as being a sink for carbon dioxide. The EPCM incorporated these extreme changes, as typified by sea-surface temperature and upwelling, in order to determine the levels of sensitivity of the model parameters to these adversive conditions. The EPCM suggests that variations in upwelling rates have a much greater effect on model parameters than a change in sea-surface temperatures. As well, it has been suggested that cooler temperatures limit zooplankton and phytoplankton parameters much more than warmer conditions. Lastly, it has been demonstrated that, according to the EPCM, the equatorial Pacific is always a source of carbon dioxide to the atmosphere. Net movement towards the atmosphere persists even during periods when upwelling is at its weakest, as simulated by the EPCM. / Thesis / Bachelor of Science (BSc)

Diss. (sammanfattning) Umeå : Univ., 2007. / Härtill 4 uppsatser.

Society’s efforts to ‘manage’ the problem of human-induced climate change – for example through setting targets, tracking progress, imposing sanctions and incentives, and creating markets in emission rights and offsets – have given rise to numerous calculation, measurement, attribution, monitoring, reporting and verification challenges, which are being addressed by many different communities (including scientists, governments, businesses and accountants) in many different ways. Carbon accounting – this diverse and ever-expanding assemblage of calculative practices – is a rapidly evolving phenomenon, which has only recently become a subject of academic accountancy-related research. This thesis explores what carbon accounting means, who it involves, and how different communities define and lay claim to competence in the field. It also examines, through case studies on the emergence of the Climate Disclosure Standards Board and the controversies around generating tradable carbon offsets from forestry projects in the UK, the immense technical, cognitive, social and political work required to make carbon measurable, commensurable and thereby amenable to various forms of management. The thesis contributes to both conceptual and practical understanding of carbon accounting as an emerging field of study. Bringing together a wide range of empirical examples of different types of carbon accounting practices, it proposes a unique definition of carbon accounting which expands the horizons of the field. It provides a conceptual basis for making sense of carbon accounting by considering it not as a unitary phenomenon but rather as a set of overlapping frames, each associated with different communities of practice. It shows that competence in carbon accounting is contested, particularly where these frames overlap, and that boundary organisations are emerging that offer the opportunity to negotiate such tensions and lead to more productive policy-making. Finally, it makes the case that engagement with the detail of the ‘nuts and bolts’ of carbon accounting is essential, as these apparently technical details can have major implications for the effectiveness of society’s response to climate change, and it is only by opening them up to rigorous scrutiny that we can make progress, both conceptually and practically.

The production of cellulose derived hybrid carbon nanofibre (CNF)/carbon nanotubes (CNTs) electrodes for the fabrication of supercapacitors and carbon fibre composites was investigated. The CNTs were grown via a floating catalyst chemical vapor deposition (CVD) method on the top surface of electrospun cellulose derived CNFs. These CNF and CNF/CNTs samples were then used as electrodes to produce liquid electrolyte-based supercapacitors. The growth of CNTs leads to an improvement of electrochemical performance compared to the plain CNFs. This improvement is due to the grown CNTs enlarging the reactive sites through enhanced surface area and porosity, and thereby increasing the conductivity of the system. CNTs have been also grown onto CNFs containing ferrocene and SiC particles. Composites were fabricated by combining the fibres and CNTs grown fibres with model polymers. The stress transfer properties of these materials have been estimated using an in situ Raman spectroscopic method by observing the shift of the Raman band during the tensile deformation of model polymer composites. Using this method, the elastic modulus of CNF/SiC/CNTs fibres has been estimated to be 208 ± 26 GPa. No shifts in the peak positions of bands relating to the carbon structure were obtained for in situ Raman spectroscopic studies of the CNF/CNTs fibres made from the ferrocene embedded fibres. This was thought to be due to the low yield of CNTs on the surface of the fibres. Furthermore, CNF/CNTs electrode-based structural supercapacitors, combining a solid electrolyte with the carbonized fibres, have been produced. These CNF/CNTs electrodes have a better capacitive performance than the plain CNF electrodes. There was a decrease in this performance with increased curing time of the resin, from 2 to 24 h, due to a lack of charge carrier mobility in the latter samples. A Raman spectroscopic study of the deformation of the carbon structures showed that the G-band shift towards a lower wavenumber position for the CNF and CNF/CNTs samples processed at a carbonization temperature of 2000 °C. Moduli of these fibres were estimated to be ~145 GPa and ~271 GPa, respectively, suggesting the growth of CNTs not only enhances the capacitive performance but also the mechanical properties of the structural supercapacitors. No Raman bend shift was found for the CNFs and CNF/CNTs samples processed below a carbonization temperature of 2000 °C, e.g. 900 °C and 1500 °C. This is because the graphitic structures are not well developed at carbonization temperatures below 1500 °C.

The drinking water treated by water treatment plant (WTP) usually has an excess of assimilable organic carbon (AOC) in distribution systems in south Taiwan. They will cause the growth of heterotrophic plate count (HPC) and deterioration of water quality in pipeline of distribution systems. Recently, part of traditional purification processes were changed into advanced processes in WTP. The past researches showed the combined advanced processes ultrafitration (UF) / reverse osmosis (RO) in south WTP in Taiwan has the removal problems of AOC in above UF / RO processes because the organic compounds in raw water caused a fouling layer which was formed on the membranes surface. These problems made the back-wash frequency increasing, short membrane life and raising cost. The study combines activated carbon and membrane bioreactor (MBR) to explore the removal efficiency of drinking water in laboratory. The system showed the removal efficiencies of dissolved organic carbon (DOC) and AOC were 57% and 36%, respectively in average. More, the system showed the removal efficiencies of DOC and AOC were 81% and 66%. The results of this research showed good removal efficiency was found in AOC and DOC. Good quality of biological stability, removal of organic compounds, low cost in building and maintaining were reached.

Urban and industrial settings represent potential areas for increased carbon (C) sequestration and storage through intensified tree growth. Consisting of an estimated 1270 ha of land once entirely forested, Burnside Industrial Park (BIP) in Dartmouth, Nova Scotia. Our study examines the degree to which intensified urban tree planting within the BIP ecosystem could enhance C sequestration and storage. This was achieved by conducting a geospatial analysis in combination with construction of a C model. Three scenarios urban forest development were examined. If all potential planting spots are filled with trees by 2020, an estimated 26,368 tC, at a sequestration rate of 635 tC/yr, could be achieved by 2050. Next, we explored the challenges and opportunities associated with pursuing C offset markets as a means for funding urban forest development within BIP. A basic framework from which a community?based C offset market could potentially be established was recommended.

Thesis (M.E.S.)--The Evergreen State College, 2007. / Title from title screen viewed (2/14/2008). Includes bibliographical references (leaves 34-40).

Thesis (M.S.)--Ohio University, August, 2000. / Title from PDF t.p.

Thesis (M. Sc.)--University of Hong Kong, 1994. / Includes bibliographical references (leaves 69-75).

Thesis (Ph.D.) -- McMaster University, 2001. / Includes bibliographical references (leaves 240-249). Also available via World Wide Web.