The identification and quantification of hydro-climatic cycles is important for un- derstanding land-atmosphere interactions, and is useful for evaluating the outputs of General Circulation Models (GCMs). This is particularly relevant in Southeast Asia, where tropical convection contributes a large influx of energy and moisture to the upper atmosphere. The analyses presented here cover interactions over a range of temporal scales, from diurnal to inter-annual. They also cover a range of spatial scales, including both observations and GCM outputs at inter-regional scales, and observations at intra-regional scales. Data Based M?delling (DBM) methods are used as an innovative way of iden- tifying climate signals from noisy data, and of estimating the uncertainties in complex environmental systems. Cycles and trends are identified using Dynamic Harmonic Regression, and rainfall and river discharges are investigated using Transfer Functions. To complement established DBM methods, a new approach is presented for analysing and comparing hydrograph peaks from different catchments . . For the inter-regional observational analyses, existing time series of observed net radiation, rainfall, latent heat flux and river discharge are obtained from typical , SE Asian regions. These series are used to identify temporal cycles and trends, and to evaluate inter-regional variations and their influences at different time scales. There are relatively few such studies available for the Tropics, so this investigation helps to fill a gap and to provide a baseline for evaluating future studies and/or GeM Land Surface Schemes (LSSs) are known to provide a POor repreSentation of climatic cycles in the humid tropics. For the inter-regional GeM model analyses, outputs from the UK Met Office HadGAMl model Were obtalned for the relevant SE Asian grid cells. These outputs were used to identify temporal dynamics in a similar way to the analysis of observations. The analysis of model outputs Was used to investigate how well the model simulates climate variability, and to explore the underlying physical processes. The analysis of intra-regional observations presents a comparison of rainfall and catchment discharges within a particular tropical region, namely the Danum Valley, in the Sabah region of Borneo. The analysis focuses on high-resolution variability in different-sized catchments, in an attempt to target the temporal and spatial resolution that characterises the humid tropics but is less well represented by LSSs within climate models.

Climate change is a pressing issue today. Drastic policy change and individual behaviour change are required to mitigate and adapt to the changes. For this to be Implemented successfully the public must be engaged. There is a shortfall in qualitative research into public engagement with climate change where engagement Is defined in terms of cognitive, affective and behavioural responses. A case study was undertaken in Bristol, UK. Focus groups were used to examine public engagement with climate change.

No description available.

Antarctic sea-ice is a critical component of the climate system, an enhancer of glacial climate and, as recently hypothesised by modelling studies, a potential driver of the millennial scale climate variability that dominated the last glacial cycle (LGC). Unfortunately a severe lack of glacial sea-ice records from the Southern Ocean has so far prevented the testing of this hypothesis with field data. In this thesis, I present detailed reconstructions of Antarctic sea-ice and ocean conditions derived from diatom assemblages and the first application of highly branched isoprenoid biomarkers to glacial sediments. These sea-ice sensitive proxies were measured in high-resolution, glacial sediment cores from the Scotia Sea (Southwest Atlantic, West Antarctica) and the Adelie Land Coast (Australia Antarctica Basin, East Antarctica). Good chronological control for the past 50 kyrs was achieved through the correlation of geochemical tracers with an oxygen isotope stack, a combination of biostratigraphic datums and relative geomagnetic palaeointensity data, and the identification of the Laschamp geomagnetic excursion at its most southerly site to date. These records permit a critical assessment of the contemporaneous nature of the regional extent, duration and seasonality of summer and winter sea-ice in West and East Antarctica during the LGC, and further afford an opportunity to determine validity of the proposed role played by Antarctic sea-ice in millennial-scale climate change through its influence on oceanography and climate. Results show that the environmental response to climate perturbations in West and East Antarctica was heterogeneous between 46.9 cal ka B.P. and 25 cal ka B.P. and broadly homogenous between ""25 cal ka B.P. and deglaciation. This study builds on existing Last Glacial Maximum (LGM) sea-ice reconstructions and shows greater summer sea-ice expansion in the Scotia Sea than previously recognised, a reduced maximum winter sea-ice extent along the Adelie Land Coast, a circum-Antarctic sea-ice maximum earlier than the LGM, decreased sea-ice seasonality in the Scotia Sea prior to maximum conditions, and an extensive period of extended sea-ice seasonality after maximum conditions. Further, this investigation has revealed close relationships between these new glacial reconstructions of Antarctic sea-ice and Antarctic Isotope Maxima, Dansgaard/Oeschger events, atmospheric CO2 variability and deep-water formation, confirming the likely importance of Antarctic sea-ice in the propagation of global millennial-scale climate change during the LGC.

Some amphibians respond to climate change by advances in phenology. Previous work at Llysdinam found significant advances in Lissotriton arrival dates in 1997-2005 compared with the 1980s. This study investigated newt migration phenology and whether early arrival reflected earlier breeding. A temporal difference was found in the size of Lissotriton newts arriving to the pond. Large newts made up a greater proportion of early arrivals. Photographic identification of ventral markings of great crested and male smooth newts was used to monitor individual movements. Breeding was not synchronous with arrival because there was a variable delay before breeding. Lissotriton eggs in Llysdinam Pond were detected ten weeks earlier in 2007 than 2006. In contrast great crested females advanced oviposition by four weeks in 2007 and prolonged oviposition by five weeks. The effect of arrival time on breeding for Lissotriton newts was studied in outdoor tanks. There was a greater delay between arrival and egg-laying for earliest Lissotriton arrivals in 2006 than 2007. There was a significant decline in the length of delay between Lissotriton arrival and egg-laying over the season, with late arrivals breeding soon after arrival. The delay between arrival and egg-laying was reduced if mean weekly air temperatures were consistently over 2 C. Lissotriton larvae and predatory aquatic invertebrates were surveyed by netting, and data compared with two studies in the 1980s. Invertebrates and newt larvae showed similar advances in phenology, but anuran spawning had not advanced indicating possible asynchronous interactions. In the absence of predators, there were no significant differences in Lissotriton hatching success or hatchling size over the season. Larvae grew faster later in the year, releasing them from predation risk by the smallest predatory invertebrates. Further research on the synchrony between species in pond habitats is suggested. If synchrony is maintained, other implications of climate change, including changes in range, susceptibility to disease and length of hydroperiod will have greater impacts on amphibian populations and possibly amphibian declines than phenological change.

No description available.

Species distribution modelling methods are used for a variety of applications including: to assess current patterns of biodiversity, to make predictions about the impacts of environmental and climate change, and to assist in conservation planning. However, important factors are often neglected both in the pre-processing of data (e.g. ignoring sampling bias), and in the construction of models (e.g. ignoring ecological processes). In terms of the pre-processing of data, recent improvements in distance sampling methods are used to convert count data to abundance estimates, utilising both distance and habitat data from a previously conducted bird count survey. Biotic interactions are studied using MaxEnt and pairs of virtual species; a novel iterative method is demonstrated, using each species prediction as a subsequent variable for the partner species. Population dynamics and dispersal are studied using RangeShifter, a recently developed individual-based model. A number of climate change adaptation actions are applied to a section of UK landscape data, and the range shifting ability of a set of focal species is measured. Many previous studies have predicted climate change impacts on species; some have started to incorporate simple measures of dispersal ability. This work demonstrates the importance of considering both dispersal and population dynamics when predicting the future distributions of species and assessing their ability to track climate change. Finally, dynamic feedbacks between species and their environment are studied by coupling RangeShifter with CRAFTY, a recently developed agent-based model of land-use dynamics. Socio-ecological system dynamics are crucial in determining species distributions, but have rarely been studied as a truly coupled system. The coupled model presented here is the first of its kind, modelling both animals and land-use agents at an individual level. A case study is presented, demonstrating the feedback mechanisms that exist between pollinators and farms that rely on them, and the potential risk posed by agricultural intensification.

Grounded in a methodology of critical discourse analysis and semi-structured interviews, this thesis investigates constructions of racial and national identities in US and EU climate security discourses. Utilizing a theoretical framework based on ‘essentializing logics’ (a concept developed to analyze how naturalized assumptions and associations about populations are held in relation to possible climate-insecure futures), the thesis argues that intersectional racial and national identities are constructed in context-specific moments of US and EU climate security discourses and are underpinned by multiple biopolitics of unequally valued lives. This argument is elaborated in three empirical chapters. First, the thesis examines the racialization of ‘Muslim’ and ‘African’ climate-induced migrant populations in particular, situated moments of climate security discourse. The second empirical chapter focuses on discursive representations of interconnections between climate change and terrorism and how such interconnections represent important points of intersection for racial and national identities in climate security. The final empirical chapter examines representations of American nationhood in US climate security discourse. These include constructions of American exceptionalism, the impacts of Hurricane Katrina and Hurricane Sandy for conceptions of American national identity, and the development of ‘climate-resilient’ American nationhood. The thesis concludes by reflecting on the project’s findings. I argue that multi-scalar interpretations of environmental justice (grounded in a manifesto for ‘abundant futures’ (Collard et al (2015)) and Koopman’s (2011) feminist ‘alter-geopolitics’) could provide a tentative means through which to think about more just, situated environmental securities.

The reliable prediction of the future climate change requires high-quality densely distributed climate records that clarify natural climate variability and its recent modulation by anthropogenic impacts. Stalagmites can meet those requirements; however, conservation concerns require new non-destructive techniques to preserve the natural environment of the caves. This thesis discusses two high-resolution Holocene climate reconstructions built using i) geochemical analyses of a Bermudan stalagmite and ii) novel and non-destructive Computed Tomography data from a Spanish stalagmite, as well as iii) supporting cave monitoring data. Considered together, these efforts provide a complementary view of diverse aspects of climate change across the North Atlantic, and provide insights into how anthropogenic CO2 emissions may further affect climate. Monitoring of environmental conditions took place at Leamington Cave (Bermuda) and Conch Bar Caves (Turks and Caicos Islands). To our knowledge, these are the first long-term monitoring efforts at coastal sites near sea level. The results of continuous monitoring of these two near shore caves in the tropical western North Atlantic are not dissimilar to previous results derived from inland caves. The microclimate and ventilation dynamics of Leamington Cave and Conch Bar Caves are controlled mainly by seasonal temperature differences between outside and cave air, wind, and rainfall totals. However, because hydrological connections with the sea, the microclimate of these near shore caves is also modulated by the seawater temperature, and sea level fluctuations. Following from the cave monitoring efforts, one stalagmite from Leamington Cave was collected. The 18O of stalagmite BER-SWI-13 provides an annually-resolved rainfall record for the last 700 years. The record suggests that the tropical cyclone activity in Bermuda following the Industrial Revolution has not exceeded its longer-term natural variability. Higher tropical cyclone activity during Bermuda’s pre-colonisation period is associated with more El Niño events and positive NAO phase and reflects the northeast-ward tropical cyclone tracks migration that coincides with the low TC activity in the Caribbean Sea. Finally, one stalagmite from southern Spain was used in a pilot study to assess the applicability of CT scanning to speleothem-based climate reconstruction. Internal density variability of stalagmite REF-07 (from Refugio Cave) was used to create a time-series record of stalagmite density, which was then linked to climate. The record reveals Holocene climate variability in southern Iberia, and suggests that the current Mediterranean climate in southern Iberia was initially emplaced at approximately 5.3 ka BP following gradual southward migration of the North Atlantic Subtropical High.

The aims of this research were to firstly help development of clumped isotope measurements of carbonate samples at UEA, and to then explore whether the technique could be used to retrieve robust environmental signals from geological material. This specifically looks at the Hirnantian glaciation at the boundary between the Ordovician and Silurian periods. Using the MIRA instrument, it is possible to make high precision measurements to enable the assessment of Earth surface temperatures. Long term precision of standard material is comparable to existing studies. MIRA is also absent of any non-linearity issues. Removal of contaminants and the identification of samples displaying contamination is stringent, as we find contamination has a serious effect on the Δ47 signal. Using modern biogenic carbonates and controlled temperature precipitates, the relationship between the clumped isotope signatures represented by the Δ47 value and temperature is: Δ47(ARF) = 3.5 x 10⁴/ T² + 0.2416. The relationship lies within measurement error of the theoretical estimate of temperature sensitivity. Applying this temperature calibration to fossil material collected from across the Ordovician/Silurian boundary found that the clumped isotope signal had been overprinted during diagenesis, and it has not been possible to extract an original Earth Surface temperature. However, the isotopic signal does show how the basin has developed during diagenesis under closed system conditions. As a result, the bulk δ¹⁸O and δ¹³C values have not been altered and record an original environmental signal.