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Following the polar amplification of global warming in recent decades, we have witnessed unprecedented changes in the coverage and seasonality of Arctic sea ice, enhanced freshwater storage within the Arctic seas, and greater nutrient demand from pelagic primary producers as the annual duration of open-ocean increases. These processes have the potential to change the phenology, species composition, productivity, and nutritional value of Arctic sea ice algal blooms, with far-reaching implications for trophic functioning and carbon cycling in the marine system. As the environmental conditions of the Arctic continue to change, the habitat for ice algae will become increasingly disrupted. Ice algal blooms, which are predominantly species of diatom, provide a concentrated food source for aquatic grazers while phytoplankton growth in the water column is limited, and can contribute up to half of annual Arctic marine primary production. Conventionally ice algae have been studied as a single community, without discriminating between individual species. However, the composition of species can vary widely between regions, and over the course of the spring, as a function of local environmental forcing. Consequently, current approaches for estimating Arctic-wide marine productivity and predicting the impact of climate warming on ice algal communities are likely inaccurate because they overlook the autecological (species-specific) responses of sea ice algae to changing ice habitat conditions. Diatom-ARCTIC will mark a new chapter in the study of sea ice algae and their production in the Arctic. Our project goes beyond others by integrating the results derived from field observations of community composition, and innovative laboratory experiments targeted at single-species of ice algae, directly into a predictive biogeochemical model. The use of a Remotely-Operated Vehicle during in situ field sampling gives us a unique opportunity to examine the spatio-temporal environmental controls on algal speciation in natural sea ice. Diatom-ARCTIC field observations will steer laboratory experiments to identify photophysiological responses of individual diatom species over a range of key growth conditions: light, salinity and nutrient availability. Additional experiments will characterise algal lipid composition as a function of growth conditions - quantifying food resource quality as a function of species composition. Furthermore, novel analytical tools, such as gas chromatography mass spectrometry and compound specific isotope analysis will be combined to better catalogue the types of lipid present in ice algae. Field and laboratory results will then be incorporated into the state-of-the-art BFM-SI biogeochemical model for ice algae, to enable accurate simulations of gross and net production in sea ice based on directly observed autecological responses. The model will be used to characterise algal productivity in different sea ice growth habitats present in the contemporary Arctic. By applying future climate scenarios to the model, we will also forecast ice algal productivity over the coming decades as sea ice habitats transform in an evolving Arctic. Our project targets a major research gap in Phase I of the CAO programme: the specific contribution of sea ice habitats to ecosystem structure and biogeochemical functioning within the Arctic Ocean. In doing so, Diatom-ARCTIC brings together and links the activities of ARCTIC-Prize and DIAPOD, while further building new collaborations between UK and German partners leading up to the 2019/20 MOSAiC campaign.

Accounting for high genetic diversity in ecologically-important traits is a fundamental problem in evolutionary biology. Individuals vary enormously at the genetic level, even within local populations, and we do not understand why. Recent work implicates an advantage to rare types as a critical factor maintaining genetic variation in many species, but we have little understanding of how this process actually unfolds in the wild. To address this gap, we need to (1) understand how ecological and social interactions promote or erode genetic diversity, and (2) link these interactions among organisms directly to the genes underlying the traits that mediate these interactions. This project will link a genetically diverse trait in the Trinidad guppy (Poecilia reticulata) to the ecological and social interactions that shape its evolution, and to the underlying genes that shape this diversity. Our previous work indicates that interactions with predators and with potential mates both favour rare colour patterns in this species. To determine which of the processes is most responsible for promoting diversity, we will collect data on predation risk and mating behaviour in multiple natural populations and relate these data to the degree of genetically-based diversity in colour patterns. Then, using populations and closely related species that vary in their genetic diversity, we will use whole-genome DNA sequencing to identify genes that control this highly variable trait. This will allow us to determine how ecological and molecular processes interact to promote or constrain evolution under balancing selection. Finally, we will directly test the idea that interactions between potential mates can maintain diversity in this species by observing evolution in real time in experimental populations with different opportunities for mate choice.

Hydraulic fracturing ('fracking') is a technology that allows the extraction of unconventional fossil fuel resources (oil and gas). The technology has been widely used in North America over the last decade but is in a much earlier stage of development in the UK. Government policy in the UK is actively encouraging the deployment of this technology and test drilling has taken place at several sites in the UK. There has been significant policy and public controversy around the use of the technology: it is simultaneously viewed by some actors as a novel and risky technology with the potential to adversely affect public health and the environment, but by others as rather more mundane and manageable. Shale gas, furthermore, is viewed by some as able to help the UK meet emissions reduction objectives but by others as hindering this task. Finally, the governance of shale gas development is also a source of conflict, with varying ideas about the ways and extent to which publics and local communities should have a say in policy and decision-making. This contested nature of shale development amongst different groups and stakeholders represents a key socio-political challenge for development in the UK. We analyse this challenge as arising from distinct ways of understanding and viewing the fracking issues ('framing') amongst different kinds of actors. We aim to improve understanding of this socio-political challenge facing shale development in the UK through an investigation of the relationships between three distinct but related research areas: public perceptions of the issue, policy debates ('frames') around shale gas and fracking, and formal processes of public engagement and participation on the matter. A nationally representative survey of public perceptions, as well as in-depth interviewing in a local community case study (the Fylde, Lancashire), will provide a better understanding of public perceptions on fracking for shale and the actors and processes of its governance, and the public acceptability of shale development in the UK. Policy debates will be analysed to better understand the arguments ('frames') put forward by advocates, their contestation, and how these debates have shaped and continue to shape UK policy. Finally, formal processes of public engagement and participation will be examined in order to assess the extent to which they help to resolve or amplify the public acceptance challenge for shale development in the UK. We are particularly interested in the relationships between these three research areas. For example, we ask, how well do policy debates reflect public views? And can the public influence decision making? Research findings will be of interest to policy makers, industry actors, regulators, environmental groups, and members of the public with an interest in the issue of fracking and shale gas development specifically, but also the issues of climate change, democracy and social controversies over technology more broadly. The primary benefit of the research will be to provide both a better understanding of the scale and nature of the social and political challenges facing shale gas development in UK, and a better understanding of the potential of public participation and engagement to help address these challenges.

The gradual shrinkage of cell sizes in mobile cellular networks and applying frequency reuse techniques has been the main approach to cope with the exponential growth of capacity demands over the last few decades. However, the outdoor deployment of 5G cells will require a large-scale expansion of the backhaul network. The most preferred backhaul solution is based on highly reliable and high-speed fibre optic links; however, their use is limited to a fraction of the current backhaul network because of overwhelming installation costs. Free space optical (FSO) communication is an attractive alternative solution that provides high-capacity but cost-effective wireless backhaul connectivity without interfering with radio frequency (RF) communication systems. However, despite decades of technological advances, FSO links still suffer from availability issues in the form of occasional long outages in adverse weather conditions. This is because classical high-speed FSO receivers such as avalanche photodiodes (APDs) may totally fail under low visibility weather conditions. The important question is, therefore, whether we can build high-speed atmospheric optical communication links that can reliably operate over all weather conditions while providing data rates beyond their RF counterparts. ARROW aims to address the question above by combining classical and quantum optical receptions to allow for adaptive operation of FSO receivers within a wide range of sensitivity levels while keeping high-speed communication. However, highly sensitive quantum detectors such as single photon avalanche diodes (SPADs) are not practically suitable for terrestrial FSO links as they can easily saturate at typically high irradiance levels experienced at such links while their bandwidth is limited by effects such as dead time. ARROW's hybrid receiver employs an APD along with a large array of SPADs integrated into a single chip. The large size of array effectively relaxes the saturation issue of the SPAD-based detector while allowing for spectrally efficient modulations that can significantly improve its achievable data rate. ARROW receivers will combine the functionality of the classical and quantum detectors using hard and soft optical switching and efficient digital signal processing to support adaptive operation based on the slow varying weather condition. In order to design efficient switching and signal processing, we will develop an accurate but tractable theoretical model that describes the hybrid channel in terms of different atmospheric effects (e.g., visibility and background light level) and their interaction with the hybrid receiver's characteristics (e.g., SPAD dead time, detectors field of view, and optical splitting ratio). Based on this model, a number of optical frontend designs and advanced modulation and joint coding schemes will be proposed to enhance both data rate and reliability of the receiver. Finally, the adaptive functionalities of the hybrid receiver will be experimentally demonstrated and validated. ARROW FSO receivers are expected to provide carrier grade availability for a wide range of practical link geometries and geographical locations.