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Shallow marine late Neogene and Quaternary sedimentary deposits around coastal Antarctica and South America contain abundant fossil bivalves, but these have rarely been utilised for palaeoclimate work. Due to their incremental growth, bivalves contain a wealth of information relating to the environment they were living in, including temperature (using δ[superscript 18]O) and productivity (using δ[superscript 13]C). A repeatable method of assessing the preservational state of fossil bivalves using a combination of techniques has been developed to ensure only pristine material is analysed for stable isotopes. These include inspection of the lamellar structure under an optical microscope, observation of luminescence using cathodoluminescence and identification of internal crystal structure using scanning electron microscopy. A targeted study of modern pectinid, cardiid and hiatellid bivalves confirm their suitability for reconstructing sea surface temperatures (SSTs), although in the case of hiatellids an understanding of the local environment is essential for an accurate interpretation of oxygen isotope records. Stable isotope analysis of pristine late Neogene (ca. 6.5 to 2.5 Ma) pectinid bivalves from James Ross Island, Antarctic Peninsula and pectinid, cardiid and hiatellid bivalves from the Vestfold and Larsemann Hills in the East Antarctic, record two distinct environmental signals: 1) warmer than present summer SSTs of up to +4.5°C, consistent with a number of other shallow-shelf and deeper water marine fossil proxies, including bryozoans, silicoflagellates and cetaceans, and with General Circulation Model simulations (e.g. PlioMIP) and, 2) seasonal fluxes of freshwater from local ice sheets, artificially decreasing δ[superscript 18]O ratios. Stable isotope analysis of late Pliocene to Quaternary (ca. 3.5 to 0.2 Ma) Chlamys bivalves and Argopecten purpuratus from the Mejillones Peninsula and Coquimbo, northern Chile, identify similar SSTs (+13 to +18°C) compared to present and suggest El Niño-Southern Oscillation (ENSO) variation has been present in the south-eastern Pacific since the late Pliocene, a signal consistent with climate model predictions. This study emphasises the importance of developing new climate proxies that identify seasonal variation, and which can be used in conjunction with other environmental proxies to provide detailed palaeoclimate data for little studied Neogene successions of the coastal zones of Antarctica and the south-eastern Pacific.

The early Eocene to the Cretaceous (48-148 Ma) was a period in the Earth's history where the climate was much warmer than the present day, with no permanent ice sheets and atmospheric CO2 levels higher than the present day. Using the climate model HadCM3L coupled to a dynamic vegetation model, this thesis aims to analyse vegetation-climate interactions during these past greenhouse climates, and how the climate, vegetation and climate sensitivity of these time periods are influenced by changes in palaeogeography and CO2 . The results of these model simulations are also evaluated against climatologically-sensitive geological proxies. Past modelling studies for the early Eocene have struggled to model the shallow equator to pole temperature gradient that data suggests was present during this time. However, most models have neglected vegetation feedbacks and incorporating these may help to reduce the model-data discrepancy. In this thesis, vegetation climate interactions during the early Eocene are modelled and analysed, and the results compared to available proxy data. The model-data discrepancies for temperatures are also reduced when vegetation feedbacks were included (compared to simulations with static vegetation), although there are still differences, particularly at high latitudes. This suggests that the models are still missing important processes or the data is not being interpreted correctly. In addition, twelve consistent simulations are carried out , each representing a different stage of the Cretaceous. Each simulation has the same atmospheric CO2 level, allowing the effect of palaeogeography on climate, climate sensitivity and vegetation to be analysed. It was found that, in general, the temperature trends that occurred in the mid-Cretaceous simulations were consistent with data. However, the data record does not extend to the earliest Cretaceous, and in the late Cretaceous the results deviate from the data. The model results suggest that, in order for the model to be consistent with the data there must have been a decline in CO2 from the early to late Cretaceous, which is supported by the CO2 proxy record. More data from the early Cretaceous needs to be collected in order to carry out a more robust model-data comparison for this time period.

Human motivation is a complex and multi-faceted aspect of individual behaviour. In the context of climate change, people can be motivated to change their lifestyles markedly to protect the planet and its resources, or seem not to care, or worry, how they impact on the planet; the reasons behind this difference are poorly understood. This study explores the internalised motivation to mitigate climate change, based on a sample of adults who perceive that they are highly motivated to reduce carbon dioxide emissions. An internal nature to a motivation produces long-term behavioural change that is not reliant on external incentives, and provides a greater satisfaction for an individual. The external rewards for taking action in the climate context are slow coming and intangible so the internal nature, backed by external coercion, is critical in responding to climate change. The three key aims of the research are to identify the common characteristics of individuals with an internalised motivation, the defining characteristics that predispose individuals to have a substantial internal nature and the contributors to the development of internalised motivation. The research is based on grounded theory, with the direction for each stage evolving from the results of the preceding stage. A complementary combination of exploratory and non-exploratory approaches and quantitative and qualitative analytical techniques is used. The research draws on previous work on models of motivation, notably from the fields of sociology and psychology. The findings confirm the validity of aspects of these models, although the particular characteristics of the climate issue do result in a shift of emphasis. It is found that there are five defining characteristics of individuals who have internalised motivation. These defining characteristics are three ethics, a sense of value, a sense of responsibility, a sense of belonging, and two capacities, an ability to make connections and an ability to self-reflect on behaviour. A sense of value, especially self-value, is the underlying contributor of internalised motivation and the other four defining characteristics are driven primarily by a feeling of competence, a strong family background, knowledge regarding the climate issue and setting local and tangible goals to improve behaviour, respectively. The ability to connect with nature in a sensual manner when visiting particular places in the natural environment is unique to individuals who have internalised motivation. The return, which is invariably the drive for human motivation, is not found to be fundamental in this climate context. It is based on achieving short-term and local changes, and lessens in importance once internalisation starts to take place. From a policy viewpoint, developing a high level of motivation to reduce emissions in a broader range of individuals requires encouraging, regular and sensual contact with nature, nurturing the belief that individuals make a difference and, last but not least, reasserting a values stance in society.

The Indus is crucial for Pakistan; economically and for water and food security. This thesis makes substantial contributions to fundamental understanding of local hydro-climatological processes in the Upper Indus Basin (UIB), essential as changes to water resources potentially affect millions of people. Drawing on a range of available data sources, complex vertical gradients are identified in several climate variables including cloud cover. The study confirms previously identified seasonally and diurnally asymmetrical temperature trends, which result in year round increasing diurnal temperature range, continue to the recent record, and describes some of the underlying causal mechanisms. Furthermore, for the first time, a stochastic weather generator is used to provide downscaled time series for 2071-2100 for two contrasting “climate scenarios” for the UIB: (i) using change factors from a Regional Climate Model (RCM) under the SRES A2 emissions scenario, (ii) extrapolating from recent observed climatic trends. A new semi-distributed basin-scale hydrological model is assembled using existing and adapted model algorithms to simulate cryosphere-hydrology interactions, including snowmelt and basic glacial mechanics. Calibrated catchment models – one glacial (Hunza) and one snowmelt-dominated (Astore) regime – are run to provide probabilistic estimates of potential hydrological changes. The RCM-derived scenario – featuring strong summer warming (> 5°C) – projects large decreases in glacial volumes (>90% and >80% mass loss in Astore and Hunza respectively) and one month earlier peak flows. The historical trends-based scenario – featuring net annual warming (0.7°C) but moderate summer cooling (~1.5°C) – also projects earlier peak flows but stable glacial areas and suppression of summer runoff from energy input constraints on melting.

The object of this thesis is to throw light on the vertical circulation in frontal zones. The partial differential equation for the stream function of the non-geostrophic motion in a frontal cross-section, first derived by Eliassen, A (1962), provides the tool for this study. A semi-objective procedure is developed, in Chapter II, for the application of the partial differential equation to a study case. The procedure is used to determine the vertical circulation of a cold front.

An idealised global atmospheric model has been used to investigate mechanisms for the persistent northern hemispheric flow anomalies that led to extreme rainfall and flooding in the UK during summer 2007 and autumn 2000. From past research the global response was obtained to forcing by idealised tropical heating anomalies based on the observed tropical OLR anomalies. The largest features of the observed tropical and sub-tropical anomalous flow were reproduced but the idealised forcing also created major features not seen, or much weaker, in the observations. The extra-tropical anomalies were well reproduced in autumn 2000 but not in summer 2007. The lack of response to tropical forcing in the extra- tropical regions of the summer hemisphere is consistent with the fact that the tropical easterlies do not allow influence through Rossby wave propagation into the extra-tropics and may also suggest other mechanisms were important. Two different methodologies were then considered, an inverse modelling technique and relaxation. In the former the model was forced with the anomalous seasonal forcing derived from the model itself while in the latter the model variables in a target region were relaxed towards analyses. Both methods stressed the importance of the tropical and extra-tropical vorticity forcing in reproducing the observed anomalies. The main forcing in the extra-tropics was found to be associated with the mid-latitude transients, while in the tropics it was associated with cumulus momentum transport and the transient nature of tropical convection in addition to heating by convection. These processes were represented in the model and it was concluded that they improve the tropical and extra-tropical responses to idealised tropical heating anomalies. They contribute significantly to the vorticity balance and must be accounted for in idealised models and diagnostic calculations.

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This thesis focuses on the communication of climate change in large corporations. Over the last 40 years, concern about climate change has increased and climateprotecting behaviour is now widely advocated by many actors, including businesses. This thesis adopts a discursive approach to climate change and aims to understand how a particular group of people, namely ‘climate champions’ in large corporations, talk and think about climate change in their daily lives. The theoretical part of the thesis begins from the assumption that neoliberalism is the dominant discourse at the beginning of the twenty-first century. It considers the relationship between neoliberalism and the natural world and examines how climate change has been discursively constructed in this neoliberal context. The main focus of the thesis is the different ways of actually dealing with climate change based on the distinction between climate change as a small ‘glitch’ in the neoliberal system and climate change as a fundamental problem. The main part of the theoretical framework identifies seven climate discourses that are rooted in this distinction. The discourses either conform to the principles of neoliberalism (reformist discourses) or reject neoliberal ideas (revolutionary discourses). Empirically, the project attempts to analyse the everyday communication of climate change by using these seven discourses. Specifically, it focuses on the role of designated ‘climate champions’ (individuals given responsibility for promoting climate protecting behaviour) in large corporations. The thesis uses interviews with 44 participants to identify which discourses the champions drew upon when they talked about climate change. It focuses on the dominance of particular discourses and how dominant ideas are reinforced or challenged on a daily basis. The thesis concludes that, although reformist discourses were indeed very influential, the champions drew upon many different discourses when they promoted climate protecting behaviour and discussed climate change. They both reinforced and resisted reformist discourses depending on the audience and the context in which they were talking.

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