This work tackles the carbon dioxide (CO2) emissions problem in power generation and process sites. The heart of the study is decarbonisation technologies.

Climate change brings with it a set of challenges if our buildings are to remain thermally comfortable whilst energy consumption is kept to a minimum and greenhouse gas emissions are reduced. As a means of addressing these issues, three models have been constructed using future climate data as forecast by the UK Climate Projections (UKCP09), and they have been used to inform the Department of Energy and Climate Change (DECC) 2050 Calculator. Observing there to be a correlation between regionalised National Grid non-daily metered gas demand and daily air temperature, the first model uses these data and UKCP09 data to estimate future energy savings deriving from a reduced requirement for space heating across the built environment. Using UKCP09 data, the second model estimates the increase in the uptake of residential air-conditioning if the UK were to follow the same experience as Canada, regression data showing a correlation between penetration levels of air-conditioning in the residential sector and air temperature in North America. Resultant levels of space cooling energy consumption are calculated using two different bottom-up approaches, the first of which uses the dwelling as the base unit, and the second of which uses the air-conditioner. Deriving from conventional degree-day theory and substantiated through a series of building simulations, the third model uses a novel metric, the Adaptive Comfort Degree-Day, to estimate the energy savings potential of employing adaptive comfort standards for future climates using UKCP09 data. Finally, it is found that pathways prescribed as achieving an 80% reduction in emissions levels by 2050 remain successful when the DECC 2050 Calculator is updated with correctly-weighted air temperatures. However, the demand for space heating is under-estimated by up to 99 TWh when the Calculator is amended so as to take account of data from the preceding space heating model.

Many environmental benefits exhibit non-excludability and non-rivalry characteristics akin to public goods. This makes it unlikely that such environmental benefits will attract a price in the marketplace. Policymakers therefore find difficulties in determining a correct economic valuation for environmental benefits exhibiting public good characteristics, leading to potentially severe consequences for aligning policy for the provision of environmental benefits with public preferences for service delivery. This research used a choice modelling approach to estimate public preferences for delivery of local and global environmental benefits; reductions in the flood risk to the British city of York (implemented by filling in drainage ditches in peat moorland further up the catchment), and a reduction in CO2 emissions (implemented by planting poplar trees for biomass either locally in the study area or elsewhere in the UK). The choice experiment presented respondents with options providing different levels of these environmental benefits with a tax as the payment vehicle. Analysis of choice experiment data revealed one latent class (LC) segment holding a significant preference for achieving a high level of CO2 reduction through national, as opposed to local tree planting, potentially indicating the existence of 'not in my backyard' (NIMBY) behaviour. Analysing the choice experiment data using the random parameter logit (RPL) model revealed mean annual public willingness to pay (WTP) estimates of £0.48-£9.55, £0.75-£14.91 and £30.93-£51.54 for levels of CO2 reduction through local and national tree planting, and flood risk reduction to York respectively. This research also quantifies the biophysical capacity to deliver levels of CO2 reduction in the choice experiment, using a combined literature review of biomass combustion characteristics and geographical information system (GIS) modelling. This indicates that national poplar tree planting can contribute towards year 2020 renewable electricity targets without greatly compromising on domestic agricultural production.

This research approaches the questions "to what future worlds of work do women executives aspire, and how might these aspirations be accomplished?" This is undertaken through a futures study within the banking and professional services industries, in which, despite over 30 years of organisational initiatives, legislation, research and social change, there are few women in executive positions.

The starting assumption in this thesis is that all resource use and associated emissions are ultimately driven by consumption, and that fundamental changes in the way society consumes are necessary. Policies aimed at shifting consumer behaviour must be based on a robust evidence-base, and the Surrey Environmental Lifestyle MApping (SELMA) framework has been developed to contribute to this. SELMA takes the consumption perspective, and at its core is an Environmental Input-Output model which attributes all resource use and associated emissions that arise along supply chains to final consumers.

Carbon dioxide sequestration using brines has emerged as a promising technology to mitigate the adverse impacts of climate change due to its large storage capacity and favourable chemistries. However, the permanent storage (mineral trapping) of CO2 in brines takes significantly long periods of time as the formation of carbonates is very slow. The main parameters (brine pH, system temperature and pressure, brine composition) have been reported to have the major effect on mineral trapping of CO2 sequestration in brines. It is suggested that the precipitation of mineral carbonates is mostly dependent on brine pH and is favoured above a basic pH of 9.0. In order to promote the formation of carbonates, brine pH could be enhanced by using additives. Synthetic brines were used in this study instead of natural brines due to the difficulty in obtaining and storing fresh natural brines. Therefore, the suitability of using synthetic brines as analogues of natural brines for CO2 sequestration studies was evaluated firstly. The experimental studies were then conducted to assess a series of additives (host rock, buffer solutions and fly ash) and select the optimal additives that could maximise the precipitation of mineral carbonates and quantify the storage capacity of CO2 via mineral trapping with additives. Finally, the geochemical modelling studies were conducted (by the code PHREEQC V2) to assess the solubility trapping of CO2 in brines with additives, and compared with the corresponding experimental results.

Marine Cloud Brightening (MCB) is one of several Solar Radiation Management (SRM) geoengineering schemes that have been proposed to counter the global warming associated with climate change. Herein an in-depth investigation of some of the climatological impacts of MCB are presented. The proposed operation of MCB is located in both the sub-tropical and tropical regions, where reflection of solar radiation from marine cloud-tops is a maximum. Work described in many publications shows that polar regions are cooled by tropical seeding. The cooling of polar regions as a result of MCB leads to an increase in polar sea-ice cover and thickness. A possible explanation for cooling the poles by seeding in the tropics is an associated change in the Meridional Heat Flux (see Chapter 5 for details). Further work has been performed to assess the effectiveness of MCB as a tech- nique for weakening tropical cyclones, which are predicted to become more severe with climate change. Reducing sea surface temperatures decreases the amount of energy available to the convective processes which power a tropical cyclone. A second investigation concerns the impact of lowering sea surface temperatures via MCB on coral reefs, which are known to be vulnerable to changes in both tempera- ture and nutrient quantities within the ocean systems. The hypothesis is that MCB could counter the temperature-increase associated with climate-change, and thus prevent coral bleaching. Simulations of MCB often seed different areas, and an attempt is made herein to use pseudo-random seeding to identify optimal seeding regions. This technique also enables assessment of the impacts of seeding any given region on several remote locations.

Despite the large quantity of research on the sensitivity of soil organic matter (SOM) degradation to temperature change, there is still no consensus as to whether soil efflux Of C02 Will increase with elevated temperatures. Understanding the mechanisms that controIC02efflux from the soil is therefore critical for predicting the response of ecosystems to climate change, particularly in polar regions where warming is occurring at rates 2-3 times greater than in temperate regions. This thesis considered two methodologies for evaluating whether soil efflux0f C02 is driven by recent inputs from plants and, secondly, the degree of temperature sensitivity. Firstly, Part I (Chapter 2) considered basal C02 and nutrient limitations in these soils. Secondly, Part 11 (Chapters 3-6) utilized 14C -labelled glucose and amino acids to assesst he mineralization of low molecular weight (MW) C in soils from the UK and Arctic and the temperature sensitivity of mineralization. UK and Svalbard soils had similar respiration rates per gram of 0 horizon and metabolism of low MW C with an exponential decay coefficient ki averaging < 1.5 h in the laboratory. However, cycling of C through the microbial biomass was significantly slower in Svalbard soils than in UK grassland soils, though when Svalbard soils were incubated at 20 OC, turnover was similar to UK field rates. Respiration measurements undertaken on an area basis were also significantly different, with the UK having much greater respiration rates, highlighting the importance of the sampling methodology when considering results. Both soils were substrate limited, indicating that respiration rates were dominated by recent contributions of labile C from plants. Temperature changes did cause an increased respiratory loss of SOM, but not to the magnitude expected with the Qjo value being < 2. Temperature dependence of SOM degradation was shown to be C pool dependent; with mineralization of labile substrate-C insensitive to temperature, but microbial biomass-C turnover and mineralization of higher MW SOM fractions increased with elevated temperatures. Partitioning of 14C changed with elevated temperatures, with more C utilized for respiration rather than growth, indicating a possible decreasein efficiency of growth at higher temperatures. Further research is needed in the temperature-dependence of SOM degradation, particularly turnover of high MW SOM, in the laboratory and field.

In light of recent upward trends in atmospheric carbon dioxide concentration, efforts have turned to methods of sequestering atmospheric carbon into other stable carbon sinks. Enhancing carbon sequestration by natural systems is an effective way of managing carbon sequestration. Due to high productivity and high sedimentation rates, salt marshes are extremely efficient at capturing and storing carbon, and provide the ideal environment for enhancing carbon sequestration rates through the management of livestock grazing, a common use of salt marshes. However, salt marshes are subject to a range of environmental stressors, which can vary considerably over a large spatial scale . It is therefore important to understand the implications of environmental and contextual variability on the use of livestock grazing as a carbon management tool. Twenty-two salt marshes were selected along the coasts of north Wales and north-west England to assess the impact of grazers on above and below-ground carbon stocks and processes in relation to broader contextual variables. The impacts of seasonality on carbon sequestration rates were also assessed by investigating a salt marsh carbon budget over the course of one year. Grazing was found to have a negative impact on several above-ground plant characteristics, but no impact on soil carbon stocks or overall carbon sequestration rates. Instead, below-ground processes were explained more by the broader environmental variables and seasonal changes. While this study does not discount the fact that grazing may affect soil carbon stocks on the small-scale, or after initial introduction, it shows that grazing impacts are insignificant relative to broader contextual factors on marshes with wellestablished grazing regimes.

This thesis brings together research conducted on field based, remote sensing and modelling approaches to meet reporting requirements set by the Kyoto Protocol. Parties are given the option to meet part of their greenhouse gases reduction requirements through the conservation and enhancement of the carbon stored in forest ecosystems. Two contrasting forests (Monks Wood, UK, 52°24' N, 0°14' W and Thetford UK, 52°30' N, 0°30' E) were selected for the development and assessment of the selected methods. Field-based measurements were used to quantify carbon stocks in Monks Wood, providing the first exhaustive assessment of the carbon content held in a UK semi-natural woodland. The total carbon content of the stands varied from 346 to 616 tonnes per hectare (t ha^-1) and highlighted the importance of broadleaved woodlands as carbon stores in the UK. A quantitative appraisal of remote sensing methods was also provided. For land cover discrimination, both optical and radar remote sensing have been successful. For forest carbon stock estimation, LiDAR approaches may provide the only viable remote sensing tool for this purpose. As a result, a LiDAR-based method was developed and the results compared to field-based estimates. At the stand level, the agreement between the field-based and the LiDAR estimates was r=0.85. At the woodland level, due to the enhanced capability of LiDAR to monitor the natural variability of carbon across the woodland, the estimates were nearly 24% lower than those from the ground. Remote sensing of field-based approaches are unsuitable alone for quantifying below-ground carbon content and can be resource intensive. Process-based models enable an estimation of below-ground components to be made. Much uncertainty however arises from the lack of information available on model parameter values. The 3-PG model was used to simulate forest production in Thetford forest and a Bayesian calibration was applied. The results showed that this statistical approach could provide an overall framework for integrating and quantifying the uncertainty in the combined field based, remote sensing and modelling datasets, a result highly relevant in the context of the Kyoto Protocol.