The Loch Lomond Advance limits and raised marine shorelines in N. W. Argyll have been mapped and surveyed. Radiocarbon dated Lateglacial and Postglacial pollen sites at Salen and Loch Shiel provide the vegetational history and chronology for the area. 14 Loch Lomond Advance glacier termini and associated limits were mapped using the distribution of hummocky and fluted moraine, together with a survey of erratic boulders. 83% of the reconstructed former glaciers had a southerly aspect relating to southerly snow-bearing winds. The average firnline gradient was 7.5m/km increasing in altitude towards the north-east; the average firnline height for the area was 369m. The Main Lateglacial Shoreline, formed during the Loch Lomond Stadial, slopes towards 270 with a gradient of 0.15m/km from 9m in the east to Om in the west of the area. It was formed by freeze-thaw action operating under exceptional conditions, and its formation was influenced by rock type. Two Postglacial shorelines are recognized : the Main Postglacial shoreline that slopes towards 270, from 14m to 8m with a gradient of 0.06m/km, and a lower shoreline at approximately 5m which has no definite gradient. An absolute Lateglacial pollen site at Salen, Ardnamurchan, shows an early pioneer community of Rumex, Salix, Gramineae and Cyperaceae species being replaced by an Empetrum heath during the Lateglacial Interstadial. Subsequent stadial conditions are reflected by open herb communities and the onset of coarse minerogenic sedimentation. This minerogenic influx ceased around 10,000 to 9,700 B.P. with a rapid recolonization of the surrounding area by pioneer herbs, then dwarf shrub and finally deciduous woodland. Middle and Late Postglacial vegetational development is recorded by lacustrine sediments from Loch Shiel where the fossil pollen record shows that a mixed deciduous woodland of Quercus, Alnus, Betula and Corylus was progressively cleared by man. Palaeomagnetic and chemical records were obtained from the site. The Main Postglacial Transgression flooded Loch Shiel resulting in the deposition of shells of the marine bivlave Thyasira flexonosa.

This thesis will examine the velocity structure of Austfonna, a large ice cap in the Svalbard archipelago. The remoteness of its location had previously hindered detailed observation by traditional methods, but indirect evidence suggested that it had the potential to be dynamically interesting. A recently developed remote sensing technique, SAR interferometry (inSAR), has allowed us to obtain the most detailed map of Austfonna's topography to date, plus unprecedented synoptic measurements of its velocity field. A four year time series of data acquired by the European Remote Sensing satellites ERS-1 and ERS-2 has been used to delineate active and inactive areas of the ice cap, which suggest that past ideas about Austfonna's thermal structure may need to be re-examined. It has also revealed large temporal velocity variations in one of its major drainage basins. These are difficult to classify because intermittent sampling has prevented us from determining their temporal wavelength, and also because globally the database of observed glacier velocity variations is so sparse that the range of possible variable flow scenarios is unknown. The work here demonstrates the huge potential for inSAR in helping to resolve such issues, and in providing an invaluable resource for scientists monitoring the stability of the world's ice fields.

The presence and configuration of subglacial water and sediment maintain the fast flow of arterial ice streams in Antarctica and airborne ice-penetrating radar data represent a potential resource of information about the ice-bed interface. In this thesis an original contribution to the exploration of Antarctic subglacial environments is made through the analysis of airborne surveys from Evans, Institute and Möller Ice Streams, West Antarctica. The primary approach employed is the derivation of bed-returned power (BRP), a proxy for ice-bed reflectivity, which is strongly influenced by the presence of liquid water. Estimating radar englacial attenuation (EA) accurately is a critical part of BRP analysis and a modelled approach is primarily used. BRP is derived across Evans Ice Stream and shows large-scale patterns relating to hypothesised hydrological and geological contrasts at the ice-bed. These results are developed to investigate the influence of: (1) adopted EA correction; (2) the influence of assigned ice dielectric properties in modelled EA; (3) subglacial roughness and (4) the spatial scale over which BRP is derived. Some areas of high basal drag can be detected with BRP analysis, indicating that variations in subglacial hydrology are responsible for their existence. The widely-used empirical method of estimating EA by relating ice thickness to uncorrected BRP is shown to be unreliable where ice properties change along a transect. Monte Carlo error analysis of modelled EA shows that poorly constrained ice dielectric properties also result in significant BRP uncertainty. BRP beneath Institute and Möller Ice Streams is derived on catchment- and local-scales over hypothesised subglacial features. Bungenstock Ice Rise is marked with a clear BRP signal but the locations of "active" lakes, as delineated by satellite altimetry, do not. The sensitivity of idealised flow paths to surface change and grid size are investigated. Potential future research directions regarding BRP analysis are discussed.

Glacier surges are amongst the most dynamic of glaciological phenomena, but their controlling mechanisms remain incompletely understood. Surging glaciers are characterised by cyclical flow instabilities and the rapid transfer of ice to the ablation area, typically resulting in significant mass loss. The High-Arctic archipelago of Svalbard is one of several regions in the northern hemisphere which contain a high-density of surge-type glaciers, variously estimated to be between 13-90% of the total glacier population across the islands. Developing a better understanding of which of these figures, if either, is most realistic is important in the context of glacier dynamics and related contributions of small glaciers and ice caps to sea level change in the immediate future. This study presents detailed assessments of the margins of several known surge-type glaciers in Svalbard in order to update and improve the existing framework by which they are identified, and to provide a foundation for future reassessments of the surge-type glacier population based on distinct ice-sediment-landform assemblages. A range of techniques is utilised, including geomorphological and structural glaciological mapping, sedimentological analysis, basal ice descriptions, and stable isotope analysis. This work provides further insight into diagnostic indicators of surge behaviour preserved in basal ice sequences; provides links between surge dynamics and basal ice sequences, the glaciological structure and the landform record; and investigates the structural and tectonic development of surge-type glaciers. Based on this, surge landsystems are proposed for: (1) small valley glaciers, (2) large land-terminating glaciers, and (3) large tidewater glaciers. It is suggested that these three landsystems, with some variability, broadly characterise the geomorphology of the vast majority of known Svalbard surge-type glaciers and, in conjunction with structural glaciological and basal ice investigations where relevant, may allow previously unknown surge-type glaciers to be identified in the field, from aerial photographs, and on sea floor imagery. This work adds to the existing repertoire of modern analogues and the breadth of surging glacier landsystems, and provides a holistic basis for assessing possible palaeo-surge behaviour within the Quaternary record.

The last two glacial terminations represent the most recent, and best documented, periods of Earth warming in the geological record. During these terminations atmospheric CO\textsubscript{2 }rose by approximately 100 ppm and global mean temperatures increased by 4-6\textsuperscript{o}C. Whilst the driver for these deglaciations ultimately derives from changes in the insolation forcing at the edge of the atmosphere, feedbacks within the Earth\textquoteright s climate system act to amplify these small external forcings tipping the Earth from a cold glacial climate state to a warm interglacial climate state. A key question in Quaternary climate science is understanding which feedbacks are important in regulating global climate on glacial-interglacial timescales. On this topic, the Southern Ocean has long been considered to be an important player in regulating atmospheric CO\textsubscript{2 } on glacial-interglacial timescales. This thesis investigates some of the hypothesised drivers of changes in atmospheric CO\textsubscript{2 } on glacial-interglacial timescales by generating high-resolution multi-proxy records from the Southern Ocean spanning the last two glacial terminations. In particular, I focus on changes in the structure, circulation and biological productivity within the sub-Antarctic zone. A change in the deep ocean density structure has been hypothesised to have resulted in the release of CO\textsubscript{2 } from the deep ocean. Centennial records from the sub-Antarctic are used to reconstruct deep and intermediate water density for the first time. I demonstrate that timing of the major breakdown in the density gradient of the ocean significantly lagged the breakdown in the chemical gradient, suggesting that changes in the deep ocean density structure were not the major driver of the deglacial rise in atmospheric CO\textsubscript{2 }. Changes in the density structure of the Southern Ocean likely had significant implications for global circulation. In particular, the flow of low salinity water through the Drake Passage is thought to be important in setting the strength and geometry of Atlantic Overturning Circulation. Drake Passage through-flow speed was reconstructed from two sites in the central and northern margins of the Antarctic Circumpolar Current downstream of Drake Passage. These records suggest a very different structure of Antarctic Circumpolar flow through Drake Passage during glacial periods, and evidence significant changes in ocean temperature as a result of pronounced reductions in Drake Passage through-flow. The strength of the biological pump has long been identified as an important player in regulating atmospheric CO\textsubscript{2 }. In particular, a strong glacial increase in sub-Antarctic productivity has been observed at open ocean sites in the South Atlantic and Indian Ocean. However, the glacial-interglacial changes in productivity in sub-Antarctic shelf settings are less well-documented. The new high-resolution records presented here from the sub-Antarctic southwest Atlantic suggest a significant change in the CaCO\textsubscript{3}:C\textsubscript{org} ratio which likely has implications for the surface ocean\textquoteright s ability to uptake CO\textsubscript{2 }.

In recent years, the study of rock glaciers has increased remarkably. Substantive progress has been made, particularly in understanding the formation of rock glaciers that have developed adjacent to existing or former valley or cirque glaciers, However, our understanding of valley-wall rock glaciers that are located at the base of talus slopes remains scant. Published work exhibits little consensus on the formation of valley-wall rock glaciers and several hypotheses remain under vigorous debate. The major objective of the research reported in this thesis has been to test the generality and feasibility of seven major models of valley-wall rock glacier formation using both empirical and theoretical evidence. The primary conclusion is that only one of these models, the segregation ice model, emerges as a general model of valley-wall rock glacier genesis. The model assumes that a thin layer or several thin layers of segregated ice are overlain by interstitially frozen sediments and an unfrozen mantle of coarse debris. A wide range of empirical and theoretical findings are shown to be consistent with the implications of the segregation ice model. Detailed observations on the morphology, sedimentology and distribution of active, inactive and relict valley-wall rock glaciers studied in Switzerland, northern Norway and Scotland provided a range of findings that support this model. Theoretical evidence was obtained by modelling a number of different density models that reflect different distribution of internal ice by applying a simple laminar flow equation to field measurements. Although only the segregation ice model appears to be valid at a general level, the possibility cannot be excluded of alternative modes of valley-wall rock glacier formation under particular circumstances. Snow avalanching, deformation of snowbank or matrix ice, and basal sliding under conditions of high hydrostatic pressure all constitute possible contributing mechanisms of formation and movement in particular cases.

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This thesis describes the parallel implementation of a three-dimensional numerical ice flow model of the whole of the grounded part of the Antarctic Ice Sheet at a grid resolution of 20km. Numerical modelling of ice flow is computationally intensive as it requires the solution of non-linear equations over long time scales. A parallel model was developed to overcome these restrictions, and it is demonstrated that the model runs more quickly on multiple processors than on a single processor (70% efficiency on four processors). The model was successfully validated against published benchmarks and compared against other models and remote sensing work. The main ice flow features are well reproduced, including some newly observed fast flow features in East Antarctica. The optimal run-time versus efficiency was exploited to run a series of detailed sensitivity tests on parameters that may affect the resulting ice sheet volume and basal thermal regime. Compared with the effects of surface air temperature, the accumulation rate and tuning parameter m in flow parameter A., geothermal heat flux was found to have the strongest effect on basal melting. It is shown that use of different geothermal heat flux values can affect the inclusion of sub-glacial lakes in the zone of basal melting. Topographic smoothing may reduce the model’s ability to locate subglacial lakes. Fast flow features appear in the modelled ice sheet despite the lack of basal slip conditions in the model. Use of a new topography data set improved the model’s ability to locate subglacial lakes in zones of basal melting, and revealed additional fast flow features in East Antarctica.