• Canada
• 2013-2022close

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.

The EcoScope project will develop an interoperable platform and a robust decision-making toolbox, available through a single public portal, to promote an efficient, ecosystem-based fisheries management. It will be guided by policy makers and scientific advisory bodies, and address ecosystem degradation and the anthropogenic impact that are causing fisheries to be unsustainably exploited across European Seas. The EcoScope Platform will organise and homogenise climatic, oceanographic, biogeochemical, biological and fisheries datasets for European Seas to a common standard type and format that will be available through interactive mapping layers. The EcoScope Toolbox, a scoring system based on assessments of all ecosystem components, ecosystem and economic models, will operate as a decision-support tool for examining fisheries management and marine policy scenarios and spatial planning simulations. Groups of end-users and stakeholders will be involved in the design, development and operation of both the platform and the toolbox. Novel assessment methods for data-poor fisheries, including non-commercial species, as well as for biodiversity and the conservation status of protected megafauna, will be used to assess the status of all ecosystem components across European Seas and test new technologies for evaluating the environmental, anthropogenic and climatic impact on ecosystems and fisheries. A series of sophisticated capacity building tools (online courses, webinars and games) will be available to stakeholders through the EcoScope Academy. The EcoScope project will provide an effective toolbox to decision makers and end-users that will be adaptive to their capacity, needs and data availability. The toolbox will incorporate methods for dealing with uncertainty; thus, it will promote efficient, holistic, sustainable, ecosystem-based fisheries management that will aid towards restoring fisheries sustainability and ensuring balance between food security and healthy seas.

Efficient air traffic management depends on reliable communications between aircraft and the air traffic control centres. However there is a lack of ground infrastructure in the Arctic to support communications via the standard VHF links (and over the Arctic Ocean such links are impossible) and communication via geostationary satellites is not possible above about 82 degrees latitude because of the curvature of the Earth. Thus for the high latitude flights it is necessary to use high frequency (HF) radio for communication. HF radio relies on reflections from the ionosphere to achieve long distance communication round the curve of the Earth. Unfortunately the high latitude ionosphere is affected by space weather disturbances that can disrupt communications. These disturbances originate with events on the Sun such as solar flares and coronal mass ejections that send out particles that are guided by the Earth's magnetic field into the regions around the poles. During such events HF radio communication can be severely disrupted and aircraft are forced to use longer low latitude routes with consequent increased flight time, fuel consumption and cost. Often, the necessity to land and refuel for these longer routes further increases the fuel consumption. The work described in this proposal cannot prevent the space weather disturbances and their effects on radio communication, but by developing a detailed understanding of the phenomena and using this to provide space weather information services the disruption to flight operations can be minimised. The occurrence of ionospheric disturbances and disruption of radio communication follows the 11-year cycle in solar activity. During the last peak in solar activity a number of events caused disruption of trans-Atlantic air routes. Disruptions to radio communications in recent years have been less frequent as we were at the low phase of the solar cycle. However, in the next few years there will be an upswing in solar activity that will produce a consequent increase in radio communications problems. The increased use of trans-polar routes and the requirement to handle greater traffic density on trans-Atlantic routes both mean that maintaining reliable high latitude communications will be even more important in the future.

NERC: Jennifer Watts: NE/S007504/1

The human mouth contains many different types of microorganisms that are often found attached to oral surfaces in 'sticky' communities called biofilms. These microorganisms are held in close proximity and will therefore likely influence the behaviour of each other. The effects of this could result in increased microbial growth, the displacement of some microorganisms to other sites, the alteration of gene expression and potentially, the enabling of microorganisms to cause infection. A PhD research project being done by Ms Megan Williams at the School of Dentistry, Cardiff University has been exploring how a fungus called Candida albicans can interact both with acrylic surfaces (used to manufacture dentures) and also with bacterial species often found alongside Candida albicans. To date, the work has indicated that colonisation of acrylic coated with different fluids, including those generated from tobacco smoking, may change the way Candida albicans grows. Candida albicans can grow as round cells called yeast, or as filamentous forms called hyphae. It is the hyphal forms that are often considered more damaging to human tissue surfaces during infection. In addition, the research shows that when certain bacteria are grown on acrylic surfaces with Candida albicans, hyphal development is also triggered. This is important, as it may mean that occurrence of infection by Candida albicans is at least in part determined by the community composition of the bacteria present alongside Candida. To date, the methods used to study these effects have included fluorescent microscopy, where the Candida is stained to fluoresce a different colour to bacteria and the surface of attachment. Whilst this approach allows quantification of attachment and imaging of the different growth forms, it cannot determine strength of cell-cell-surface interactions. Atomic Force Microscopy (AFM) is a method that provides images through measuring forces acting between a moving probe and a surface. It is possible to attach different molecules and even whole bacteria to the AFM probe, and in doing so, we can measure interactions occurring between bacteria, and either Candida yeast or hyphae serving as the substrate. Dr Laurent Bozec and his team at the University of Toronto are experts in use of AFM, which is not available in the School of dentistry, Cardiff. The exchange therefore offers the PhD student the opportunity to learn a new experimental technique, generate important data for the PhD and benefit from unique networking experiences. The results generated from this proposal will greatly enhance the research output and complement existing findings of the PhD. Ultimately, this could help determine how bacteria physically interact with Candida albicans and trigger the development of hyphal filaments to facilitate infection.

Recent literature has underlined the interplay among climate mitigation, adaptation, and finance, as well as between climate action and other development agendas, including sustainable resource use, human development and equity, and environmental pressures. Such an interconnected policy environment requires an integrated ecosystem of disciplines, methods, and tools. Despite the significant evolution of integrated assessment models (IAMs) in the last decade, there remain several criticisms on their design, use, and adequacy to respond to unaddressed and emerging questions in the light of the Paris Agreement and net-zero ambition. These include openness, legitimacy, and ownership, as well as technical feasibility to represent demand-side and broader societal transformations, cross-sectoral interactions, physical impacts and adaptation, climate finance and labour dynamics, and other sustainability goals. DIAMOND will update, upgrade, and fully open six IAMs that are emblematic in scientific and policy processes, improving their sectoral and technological detail, spatiotemporal resolution, and geographic granularity. It will further enhance modelling capacity to assess the feasibility and desirability of Paris-compliant mitigation pathways, their interplay with adaptation, circular economy, and other SDGs, their distributional and equity effects, and their resilience to extremes, as well as robust risk management and investment strategies. This will be done via integration of tools and insights from psychology, finance research, behavioural and labour economics, operational research, and physical science. We will develop a transdisciplinary scientific approach to legitimise the implementation process and co-create research questions that stretch the frontiers of climate science, as well as establish vibrant communities of practice to transparently open model enhancements and to develop capacities, thereby lowering the entrance barriers to the established IAM community.

Methane is a powerful long-lived greenhouse gas that is second only to carbon dioxide in its radiative forcing potential. Understanding the Earth's methane cycle at regional scales is a necessary step for evaluating the effectiveness of methane emission reduction schemes, detecting changes in biological sources and sinks of methane that are influenced by climate, and predicting and perhaps mitigating future methane emissions. The growth rate of atmospheric methane has slowed since the 1990s but it continues to show considerable year-to-year variability that cannot be adequately explained. Some of the variability is caused by the influence of weather on systems in which methane is produced biologically. When an anomalous increase in atmospheric methane is detected in the northern hemisphere that links to warm weather conditions, typically wetlands and peatlands are thought to be the cause. However, small lakes and ponds commonly are overlooked as potential major sources of methane emissions. Lakes historically have been regarded as minor emitters of methane because diffusive fluxes during summer months are negligible. This notion has persisted until recently even though measurements beginning in the 1990s have consistently shown that significant amounts of methane are emitted from northern lakes during spring and autumn. In the winter time the ice cover isolates lake water from the atmosphere and the water column become poor in oxygen and stratified. Methane production increases in bottom sediment and the gas spreads through the water column with some methane-rich bubbles rising upwards and becoming trapped in the ice cover as it thickens downward in late winter. In spring when the ice melts the gas is released. Through changes in temperature and the influence of wind the lake water column mixes and deeper accumulations of methane are lost to the atmosphere. In summer the water column stratifies again and methane accumulates once more in the bottom sediments. When the water column become thermally unstable in the autumn and eventually overturns the deep methane is once again released although a greater proportion of it appears to be consumed by bacteria in the autumn. Lakes differ in the chemistry of their water as well as the geometry of their basins. Thus it is difficult to be certain that all lakes will behave in this way but for many it seems likely. The proposed study will measure the build-up of methane in lakes during spring and autumn across a range of ecological zones in North America. The focus will be on spring build-up and emissions because that gas is the least likely to be influenced by methane-consuming bacteria. However, detailed measurements of methane emissions will also be made in the autumn at a subset of lakes. The measurements will then be scaled to a regional level using remote sensing data providing a 'bottom-up' estimate of spring and autumn methane fluxes. Those results will be compared to a 'top-down' estimate determined using a Met Office dispersion model that back-calculates the path of air masses for which the concentration of atmospheric methane has been measured at global monitoring stations in order to determine how much methane had to be added to the air during its passage through a region. Comparing estimates by these two approaches will provide independent assessments of the potential impact of seasonal methane fluxes from northern lakes. In addition measurements of the light and heavy versions of carbon and hydrogen atoms in methane (C, H) and water (H) will be measured to evaluate their potential use as tracer for uniquely identifying methane released by lakes at different latitudes. If successful the proposed study has the potential to yield a step-change in our perception of the methane cycle by demonstrating conclusively that a second major weather-sensitive source of biological methane contributes to year-to-year shifts in the growth rate of atmospheric methane.