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Along the western margin of Spitsbergen, where the northern extension of Gulf Stream system conveys warm Atlantic water into the Arctic Ocean, hundreds of plumes of bubbles of methane gas were discovered in 2008, rising from the seabed at a depth close to that of the landward limit of the methane hydrate stability zone. Methane hydrate is a solid with the appearance of ice, in which water forms a cage-like structure enclosing molecules of methane. Methane hydrate is stable under conditions of low temperature and high pressure such as those found in regions of permafrost or under the ocean in water deeper than 300-600 metres, depending on the water temperature. Over the past thirty years, the ocean's temperature at the seabed has increased by 1 degree C, causing the zone in which hydrate is stable to contract down the continental slope, with the apparent consequence that hydrate has broken down and released methane, which has migrated to the seabed and into the ocean. At present, the rate of release of methane is generally too slow to overcome dissolution and oxidation in the ocean to reach the atmosphere, except in very small quantities. However, catastrophic gas venting, which is known to occur elsewhere, could release large amounts of methane over a short period of time. The strength of such venting depends upon the how much gas is stored locally beneath the seabed and the kinds of pathways that bring gas to the seabed. The proposed research seeks to define these pathways and to quantify the amount of gas. A marine research expedition will use a deep-towed, very high-resolution seismic system to image the small-scale structures that convey gas to the seabed and to detect the presence of gas in the sediments beneath the seabed. This will be done in conjunction with an electromagnetic exploration system that uses a deep-towed transmitter and receivers on the seabed to derive the variations in electrical resistivity in the sediments beneath the seabed. Higher-than-normal resistivity is caused by both gas and hydrate, whereas the presence of gas reduces seismic velocity and hydrate increases it. In combination, the two techniques can distinguish the separate amounts of hydrate and gas. The deep-towed seismic system, SYSIF, which uses a piezo-electric chirp source that gives very-high-resolution images and deeper sub-seabed penetration than similar systems mounted on a ship's hull, will be supplemented by the use of ocean-bottom seismometers to provide precise measurements of the variation of seismic velocity with depth, and seismic profiles with small airgun (mini-GI gun) to provide deeper high-resolution seismic imaging. Multibeam sonar will be used to improve definition of the shape of the seabed and high-frequency, fish-finding sonar will image plumes of gas bubbles and define their positions, providing, in many cases, comparisons with the images obtained in 2008 when they were first discovered. Two areas will be investigated, the region of the landward limit of the methane hydrate stability zone, where many bubble plumes occur in water shallower than 400 metres, and, for comparison, a pockmark in the Vestnesa Ridge, at a depth 1200 metres, from which gas is escaping and is underlain by 'chimneys' that convey gas to the seabed through the hydrate stability zone, where the gas would normally form hydrate. Geological and geophysical data, including 96-channel seismic reflection profiles, acquired in both areas during a research cruise in 2008, will complement the new data. The project will provide the sub-seabed context for a seabed observatory (MASOX Monitoring Arctic Seafloor - Ocean Exchange), which will be established in the shallow plume area in summer 2010 by a European scientific consortium to monitor the activity of the plumes and the physical and chemical fluxes through the seabed.

Visible-band satellite images have been a valuable tool in marine science for 30 years. Through them we have learned a great deal about the distribution and seasonal variation of phytoplankton in the ocean. It has been possible to estimate primary production and the role the oceans play in taking up carbon dioxide from the atmosphere. In shelf seas, visible band images have enabled us to map out the concentration of small inorganic sediment particles stirred up from the sea bed. In both of these applications the particles are visible because they absorb and scatter sunlight. An important question, to which the answer is not at all clear at present, is exactly how large the particles are that are mainly responsible for scattering the light that is 'seen' by the satellites. It is often assumed that the size distribution of particles in the ocean follows a 'Junge' distribution, in which the number of particles increases rapidly as the size of the particles decrease. With this assumption, and using an optical theory which assumes spherical particles, it has been shown that most of the light scattering is performed by particles smaller than 1 micron in diameter. If this were true, it would mean that the particles seen in satellite imagery are mostly very small with slow settling speeds and long residence times in the surface of the ocean. This would have important implications for those who interpret these images and who use them to verify numerical models of particles in the ocean. However, no-one has ever directly observed in the sea the numbers of such small particles predicted by the Junge distribution. Photographs of undisturbed samples of seawater show that particles tend to gather together in 'flocs'. The measurements of particle size distribution which support the Junge distribution use a disruptive technique which potentially breaks up flocs and hence possibly over-estimates the number of small particles. Current instruments designed to measure the size of particles in situ and without disturbance are limited to particles greater than a few microns in size and hence greater than the critical particle size thought to be important in remote sensing. Holgraphic cameras enable focused images of small particles suspended in water to be made. The camera images the diffraction pattern of the particle and the particle is then reconstructed mathematically from this pattern. In the case of small particles, the diffraction pattern is much larger than the particle itself and so the holographic technique can reconstruct very small particles indeed, smaller than the wavelength of light, which cannot be measured in any other way. We have demonstrated this technique in the laboratory and imaged particles down to about 0.5 micron. With further magnification and improved optics it will be possible to image particles down to 0.2 micron. In this proposal we will package this technology for field work. By using different magnifications and commercially available in situ particle sizing instruments, we can make a package of instruments for measuring the undisturbed particle size distributions from 0.2 micron to 1 mm. This package will first be used in a turbulence tank to 'film' the flocculation process. The insight this gives will be used to construct new theoretical models of the particle size distribution. Field work will be carried out at one coastal site over a seasonal cycle and at sea through a variety of water types before and after the spring bloom. We will also make improved measurements of absorption and scattering by particles. Because the camera also measures the shape of the particles, differences between observed and calculated optical properties can be compared, for the first time, to particle shape. Finally, we will put together the complete data set to determine what size particles, under what conditions, are primarily responsible for the signals seen in visible band satellite images of the oceans.

Why is the world's upper ocean supersaturated with methane? We know that it is, but do not understand why. Evidence shows that a portion of the methane comes from in situ production in oxygenated waters, however that seems to contradict all we know about methanogenesis; a strictly anaerobic process. This phenomenon has been termed the 'oceanic methane paradox'. If, however, there were anaerobic microsites in the upper ocean, then it is entirely possible that methanogenesis could occur within them. We now think that marine zooplankton, their excreted faecal material and other sedimenting particles may provide these anaerobic microsites in pelagic waters. Work conducted by our research group at SAMS supports this hypothesis. We have now clearly identified the presence of methanogens (methane producing microorganisms) within marine zooplankton faecal pellets and sedimenting particles. This, along with data showing that elevated methane concentrations are associated with these sites, has led to greater insights into how this anaerobic process may be actively occurring in pelagic waters. We also know that methanogens can use a range of substrates, including carbon dioxide and formate. However, some of the methanogens we have studied from zooplankton faecal pellets are affiliated with the genus Methanolobus, and are thought to utilize one-carbon (C1)-compounds, including dimethylsulphide (DMS) and methylamines (MAs). Potential sources of these two compounds are dimethylsulphoniopropionate (DMSP) and glycine betaine (GB), which are produced by marine phytoplankton to maintain their osmotic balance in seawater. It is likely that when zooplankton eat phytoplankton they consume at least some of the DMSP or GB, which is then packaged into their faecal pellets. DMSP and GB are thought to be converted into DMS and MAs respectively by microbial activity. Grazing therefore represents a pathway for these C1-compounds to enter into the zooplankton gut and faecal pellets, where they may be substrates for methanogenesis. It is thought that aerosol particles generated from either DMS or MAs may contribute to the pH of natural precipitation and play a role in climate control due to their influence on cloud albedo and reflection of solar radiation. Therefore, zooplankton faecal pellets could be instrumental sites both in the production of a greenhouse gas and the removal of climatic feedback gases, having important consequences for our understanding and modelling of the role the oceans play in climate change. We propose to conduct a multidisciplinary project that will further our understanding of the role of zooplankton, their faecal pellets and sedimenting particles as potential sites of in situ methanogenesis in the water column. Our main purpose is to clarify the role of algal derived compounds in methanogenesis, determine the importance of syntrophic relationships in this process and investigate the use of alternative substrates within these sites. This should enable us to determine the main methanogenic groups responsible for this process and how they are influenced by their environment and other microorganisms. The prerequisites for this work have been demonstrated by the group at SAMS and others. However, much of this work, though exciting, is preliminary and the processes remains poorly understood. Research will be carried out using both state of the art techniques (including real-time PCR, stable isotope probing, stable isotope mass spectrometry, CARD-FISH) and established analytical and microbiological methods (culture & culture independent). In addition, through the work of a tied studentship, we hope to add exciting new aspects to this work including further characterisation of isolated methanogens and an increased understanding of their location using CARD-FISH and confocal microscopy. By combining these areas of research with new methodology we hope to start to unravel the ocean methane paradox.

Writing good computer programs that model complex phenomena, such as the weather and climate change, to run on the fastest computers is necessary to allow scientific investigation to proceed as rapidly as possible. The development of new codes involves experts in several different areas to cooperate: the scientist has to has to develop the mathematical model that will provide the desired scientific insights, algorithm developers have to turn the model into a step-by-step procedure which enables the model to be applied to a particular problem (calculating tomorrows weather from today's, or predicting the climate in a hundred years time). Finally, the algorithm has to be coded in a programming language that enables a computer to do the calculations for the scientist. Computers continue to get faster, and the technology used to build them is constantly changing, leading to new challenges for algorithm and program developers. This project brings together experts from each of the areas of expertise who will work together to create the next generation of a key component in weather and climate simulation, the dynamical core, which, basically, models the movement of air in the atmosphere. Our contribution to this effort is to help make sure that the algorithms developed can be efficiently programmed for running on today's computers and be easily moved to future computers, despite changes in hardware technology.

Globally, forests contain a vast reservoir of carbon, approximately 30% of that in the biosphere, much of which is in the form of woody plant tissues. Every year this is added to as plants photosynthesise, but in balanced systems a similar amount is broken down to CO2 and water, and nutrients are released. Understanding what controls this balance is crucial for understanding carbon cycling, and for predicting carbon cycle responses to global climate changes. Recycling of woody resources is almost exclusively confined to a narrow range of specialist fungi: basidiomycetes and a few ascomycetes. Thus, these fungi are central to carbon and nutrient cycling, and yet we still have relatively little understanding of how they grow in wood, how they interact with each other and how different community composition affects decay. Key objectives of this proposal are, therefore, to unravel these processes, and to obtain quantitative data on the way in which fungal communities influence wood decay rate to be able to incorporate these dynamics into global models of carbon cycling. The majority of decay takes place in fallen wood, but wood decay actually begins in standing dead parts of trunks and attached dead branches. Moreover, the fungi that start the process are already latently present while the tissues are still functional. When the wood dries, the latent fungi grow throughout the wood as mycelium and begin the decay process. Later, other fungi, arriving as spores, 'fight' with those already present. Preliminary evidence suggests that fungal community composition, when species become established, and how they interact with each other, have a dramatic effect on the rates of wood decay and thus carbon cycling. We have a general understanding of factors affecting the process built from studies on fungal communities developing in attached branches, and from felled wood, but felled logs do not reflect the situation in nature as they are not already well colonized. In this project we will for the first time investigate community development when naturally colonized wood falls to the forest floor. We will simulate naturally fallen wood by pre-colonising wood slices with fungi that are primary colonizers of attached beech branches. Firstly, we will determine whether certain species effectively 'select' which fungi follow them, by leaving colonized slices on the forest floor and collecting after different times, using new high throughput DNA sequencing technologies and traditional isolation onto agar. Secondly, we will quantify wood decay rate, by measuring loss of density of slices in the field experiment. Thus, we will relate the species mix of primary and later colonisers with decay rate. As decay in the field will also be affected by climatic variables etc., we will also perform lab experiments on the effect on decay rate of adding specific later colonisers to slices pre-colonised with specific primary colonisers, by measuring CO2 evolution and weight loss. Thirdly, we will study how antagonistic interactions between fungi affect decay rate. When fungi interact, the outcome can be deadlock in which neither species gains territory, or replacement of one species by the other. A preliminary study has indicated that decay rate actually changes during the course of replacement of one fungus by another. We will investigate this in detail and also ask whether the outcome of the interaction is related to decay rate, by following CO2 evolution during the interaction. Finally we want to know how different numbers of individuals/species affects decay rate. We will precolonize wood slices and then vary the number of individual strains added, and measure decay rate in the laboratory under standard conditions. This project will reveal how fungal communities alter, how communities affect decay rate, provide data for carbon cycling models, and possibly form the basis for future manipulations of fungal communities to optimise carbon cycling.

Intense extratropical cyclones are one of the major weather risks in the mid-latitudes. High winds and extreme precipitation from extratropical cyclones can result in windstorm damage, flooding and coastal storm surge. Understanding the impacts of climate change on extratropical cyclones is critical to assessing future weather risk. TEMPEST is a 3-year proposed programme of research addressing the climate science deliverable of the NERC Storm Risk Mitigation directed programme. The climate deliverable is to provide an improved understanding of how climate change and natural variability will affect the generation and evolution of extra-tropical cyclones. TEMPEST will achieve this improved understanding by addressing the scientific questions raised in the Storm Risk Mitigation climate deliverable. TEMPEST aims to address these questions by, Providing the first systematic assessment of how intense extratropical cyclones are predicted to change in the Fifth Coupled Model Intercomparison Project (CMIP5) climate models Performing an integrated set of sensitivity experiments with the Met Office Unified Model to quantify the key processes that determine the spread of climate model predictions Investigating the response of intense extratropical cyclones to climate change in very high-resolution global atmospheric model experiments capable of capturing mesoscale structures. The focus in TEMPEST is on intense extratropical cyclones that affect Europe. This is partly due to the socioeconomic impacts of such storms, but is also partly driven by the scientific need to address the particularly large spread in climate model predictions for extratropical cyclone activity over the North Atlantic and Europe. It is envisaged that the outcomes from TEMPEST will feed directly into the forthcoming IPCC assessment report (AR5). TEMPEST will also have strong synergies with other LWEC (Living With Environmental Change) programmes, most notably the JWCRP (Joint Met Office/NERC Weather and Climate Research Programme) and the CWC (Changing Water Cycle) research programme. The questions posed by the Storm Risk Mitigation climate deliverable cut across the traditional boundaries of weather and climate modelling communities. To tackle these questions, we aim to bring together scientists from the climate, weather and statistical communities at the Universities of Exeter, Oxford and Reading, the Met Office and ECMWF (European Centre for Medium-Range Weather Forecasts). By engaging the wider community within TEMPEST, we will enable the development of links with the Impacts and Numerical Weather Prediction projects in the Storm Risk Mitigation programme.

The radioactive decay of uranium incorporated in natural carbonates (e.g. corals and stalagmites) provides a powerful way of dating these materials. Such U-Th techniques extend to about half a million years ago and provide the major way in which we can learn about the timing of past climate and environmental change. Over the past 15 years there has been considerable improvement in our ability to measure U and Th isotope ratios and concentrations resulting in a reduction of U-Th age uncertainties by an order of magnitude. Uncertainties are now as low as 0.1%, or 100 years in the age of fossil coral or speleothem that is 100,000 years old. This increase in precision has enabled a wide and expanding range of questions to be answered and is critical to our understanding of the mechanisms of Pleistocene climate and sea-level change. But it has also exposed a problem. Calibration of the tracer solutions used to make U and Th measurements is performed independently in each laboratory using differing techniques and it has become abundantly clear that resulting U-Th ages, while impressively precise, do not agree at this level of precision from one lab to another. There is now inter-laboratory bias at a level that exceeds typical quoted age uncertainty. The cause of this inter-laboratory uncertainty is due to a lack of suitable materials for both calibration purposes and for long-term assessment inter-laboratory agreement. One of the most widely used materials for such calibration, HU-1, has recently been demonstrated to vary, by up to 0.5% between the solutions used in different laboratories. And there exists no widely distributed and well characterised 'age standards' that could be analysed by all of the U-Th laboratories to facilitate quantification of inter-laboratory agreement. We propose a series of actions to address these short fallings in the international U-Th chronology community. We will develop a series of U-Th calibration solutions who's composition is known from first principles metrology (i.e. from the weighing and dissolution of high-purity U and Th metal). We will use these solutions to calibrate the tracers used in three UK and one overseas laboratories - each with a well established reputation for U-Th work. We will then proceed to do develop four different 'age solutions' by taking the U and Th isotopes and mixing them together in proportions that mimic typical compositions analysed by the community. The composition of these 'age solutions' will be measured using the newly and precisely calibrated tracers, so that all compositions will be known and traceable to basic measurements of mass. These 'age solutions' will also be made freely available to all U-Th laboratories who request them worldwide, and we will produce enough of the solutions so that they will last the community 20 years. We will co-ordinate an inter-laboratory comparison exercise so that, for the first time, we will be able to quantify the level to which dates produced in different laboratories agree. As a community we will want to ensure that the level of inter-laboratory variation is minimised, so if labs find their results to be inaccurate they will be able to use the age-solutions, whose compositions are well known, to improve the accuracy of their results. There is very widespread support for this effort in the international U-Th community and we have letters of support from 33 laboratories - the vast majority of all such laboratories worldwide. There are also limitations with the mathematical treatment of U-Th data used to produce dates. Our proposed analytical efforts will be made in concert with the development of these new data reduction template. Overall, these activities will provide dramatic and permanent increase in the reliability of U-Th dates of carbonates - the dates on which so much of our knowledge of Pleistocene climate is based.

Chemicals entering the atmosphere come from a number of sources, but in broad terms are either from human activity or from the biosphere (natural systems). What happens to these chemicals once in the atmosphere is very important of course. If they are toxic they can impact on the health of humans, animals and natural ecosystems. Therefore, it is vital that we understand how pollutants are removed by the atmosphere. One very important removal process involves the so called hydroxyl radical. This is an extremely reactive species that acts like a chemical detergent, destroying pollutants and cleaning up the atmosphere. It has emerged in recent investigations that an important source of the hydroxyl radical must be coming from Criegee radicals. However, these Criegee radicals have been impossible to measure until recently. Work carried out by us, using a facility in the USA, has allowed us to observe a Criegee radical for the first time. In this project we will develop a state-of-the-art experimental system that will allow us to investigate the chemistry of Criegee radicals and therefore to help us to understand how they affect the amount of hydroxyl radical is present in the atmosphere. Such work will not only improve our understanding of the urban environment but will also have implications for climate studies as well. Reactions of Criegee intermediates, over a wide range of pressure and temperature, are of importance in atmospheric chemistry. The proposed UV-PE apparatus will be the first of its kind and will enable us to carry out a range of experiments to study reactions of these radicals that, as far as we are aware, no one else in the world can do. To demonstrate how versatile the apparatus is we propose a carefully designed set of experiments to look at the source and fate of Criegee radicals in the troposphere. Quantum chemistry calculations of the reactions studied will provide detailed understanding of their mechanisms and the kinetic data will be incorporated into models describing the troposphere and compared with available measurements.

Noise is a problem whenever animals collect information from their environment. It can affect them in many negative ways. These include whale strandings in response to Navy sonars, hearing damage, increased stress and the avoidance of areas they would otherwise use. Communication sounds can also be affected by noise when they become less obvious in a noisy environment. While many studies have addressed the question of how animals communicate with each other, we still know relatively little about how they use other sounds they hear. Some work has reported that predators use movement sounds of their prey to locate and catch it. Since many animals can learn about sounds they may use them in even more ways to gather information about their environment. For example, a waterfall may be used as an acoustic landmark to find a foraging site or reflection of ambient noise may be used to detect an object in darkness. These possibilities suggest that there is another side to noise, a positive one that can be used by animals for orientation. The project proposed here will investigate this positive side of noise in seals. Sound travels better in water than in air, while visibility is often low. Thus, positive effects of noise are easier to study in this environment. The first part of the project will investigate whether seals can use noise that is reflected or blocked by objects to detect the objects themselves. If so, an increased noise level may make objects more detectable to seals. For this, we will train blind-folded seals to report when they detect an object that is presented to them in front of an underwater speaker. We will investigate at what distances the seal is able to detect an object in this way, how loud the noise needs to be and whether the noise needs to come from a particular directions to maximise detection. In the second experiment we want to find out whether seals will spontaneously learn to associate a novel sound source with a specific geographic location. For this, we will install such a noise source near a seal haul-out site and then test how seals from that site react to this noise when the are taken to another location. Will they approach the noise source when searching for their haul-out site, even if it has been moved to another location? Finally, we want to know whether seals in the wild learn about sounds produced by humans when looking for food. Many fish farms use acoustic devices that are supposed to keep seals away. However, many reports suggest that these sounds might attract seals just like a dinner bell. We will install an underwater speaker near a fish farm to see whether the seals are more likely to approach when we play the sounds used on the farm as compared to other control noises. Still looking at foraging, we will also provide captive seals with various sand trays with buried fish, some of which also have fish tags in them that make a sound. These tags are widely used to track fish in the wild. We want to know whether seals learn to associate the audible ping with the food in the tray, so that after a while they seek out trays with fish tags. Taken together, these studies will inform us about how seals use noise in their environment in a way that might help them rather than disturb them. While the negative effects of noise most likely outweigh any positive sides, it is still important to know both sides of the story. If seals can use ambient noise detect objects, collisions with marine turbines and engines might be less likely than we think. Similarly, the effects of noises that we introduce are important to understand. If we remove an acoustic landmark that we have provided by installing a turbine or other machinery, this might affect animals. Similarly, sounds that we use to track fish or keep seals away may have an attraction effect, which leads to undesirable results for the people using them.

Current best estimates indicate that approximately 5M people living in 2M properties are at risk of flooding resulting from extreme storms in the UK. Of these approximately 200,000 homes are not protected against a 1 in 75 year recurrence interval event, the Government's minimum recommended level of protection. When major floods do occur then total damage costs are high (£3.5Bn for the summer 2007 floods) and the total annual spending on flood defence approaches £800M. Protecting this population and minimizing these costs into the future requires the development of robust hydrologic and hydraulic models to translate the outputs from Numerical Weather Prediction (NWP) and climate models into meaningful estimates of impact (with uncertainty). These predictions of impact can then be used to plan investment decisions, provide real-time warnings, design flood defence schemes and generally help better manage storm risks and mitigate the effects of dangerous climate change. Building on foundations developed by consortium members as part of the NERC Flood Risk from Extreme Events (FREE) and EPSRC/NERC Flood Risk Management Research Consortium (FRMRC) Programmes, we here propose an integrated programme of research that will lead to step change improvements in our ability to quantify storm impacts over both the short and long term. Based on the knowledge gained in the above programmes, we suggest that improvements in storm impact modelling can be achieved through four linked objectives which we are uniquely positioned to deliver. Specifically, these are: 1. Downscaling, uncertainty propagation and evaluation of hydrologic modelling structures. 2. The development of data assimilation and remote sensing approaches to enhance predictions from storm impact models. 3. Better error propagation through coastal storm surge models. 4. The development of a new class of hydraulic model that can be used to convert predictions of rainfall-runoff or coastal extreme water levels to estimates of flood extent and depth at the resolution of LiDAR data (~1 - 2m horizontal resolution) over whole city regions using a true momentum-conserving approach. In this proposal we evaluate the potential of the above four approaches to reduce the uncertainty in ensemble predictions of storm impact given typical errors in the NWP and climate model outputs which are used as boundary forcing for impact modelling chains. Our initial characterization of the errors in predicted storm features (spatial rainfall and wind speed fields) in current implementations of NWP and climate models will be based on existing studies conducted by the UK Met Office and the University of Reading. As the project proceeds we will use the advances in storm modelling being developed for Deliverables 1 and 2 of this call to enhance our error characterizations and ensure that the techniques we develop are appropriate for current and future meteorological modelling technologies. We will rigorously evaluate the success of our proposed methods through the use of unique benchmark data sets of storm impact being developed at the Universities of Bristol and Reading.