This joint proposal to U.S. National Science Foundation's Directorate for Geosciences and U.K. Natural Environment Research Council aims to investigate how the Oyashio Extension frontal variability in the Northwest Pacific Ocean influences the large-scale atmospheric circulation by accumulating the interaction between the individual weather system and underlying ocean front. The atmospheric storm track exhibits the local maximum strength in the Northwest Pacific over the strong ocean fronts driven by collocated maximum baroclinicity, which is in turn maintained by huge heat and moisture supplied by the ocean. While significant advances have been achieved in the past decade or so on our understanding of ocean front's impact on the atmosphere for the mean climate, there are still many crucial questions yet to be answered, especially related to impact of ocean frontal variability on the atmospheric circulation variability. A particular goal of this proposal is to unveil the link between the local air-sea interaction in weather scale near the Oyashio Extension and its cumulative impact on the large-scale atmospheric circulation and climate variability. Specific emphases will be placed on the seasonality of this link by contrasting the early and late winter, and also the asymmetry/nonlinearity in the large-scale atmospheric response to warm and cold SST anomalies induced by a shift of the Oyashio Extension front to the north and south, respectively. These challenging goals will be addressed by combining analyses of observational and reanalysis datasets and targeted climate model experiments using the Variable Resolution Community Atmosphere Model v.6 with Spectral Element dynamical-core, a state-of-the art atmospheric general circulation model, which will be configured with a very high-resolution over the North Pacific and lower resolution elsewhere globally to realistically simulate the frontal air-sea interaction over the Oyashio Extension as well as the feedback with the large-scale circulation at a manageable computational cost. Furthermore, the role of local ocean coupling will be investigated by comparing the atmosphere-only simulations with those coupled to the 1-dimensional column ocean model.

The atmosphere of the Earth is an oxidising medium. The atmosphere directly above the Antarctica plateau is thought to be a pristine clean environment, however the oxidising capacity of the Antarctic atmosphere has recently been found to be very high. Emission of nitrogen oxides (NO, NO2 and HONO) and oxidised compounds such as HCHO and H2O2 from the snowpack are thought to be responsible. The chemical emissions are mainly driven by photochemical reactions in the snow, i.e. the action of sunlight on snowpack drives photolysis of nitrate and hydrogen peroxide in the snow to produce fluxes of nitrogen oxides from the snowpack and hydroxyl radical reactions in the snowpack. Snow is an excellent medium for photochemical reactions owing to the enhancement in the light flux in the top 10cm of the snow relative to the atmosphere above. Previous studies of this snow-atmosphere chemistry have tended to concentrate on either atmospheric measurements and/or polar coastal sites. One aim of this investigation is to explore and explain the high atmospheric oxidising capacity over plateau continental Antarctica and link this chemistry with measurement and atmospheric chemistry/transport modelling studies with stations on costal Antarctica. Coastal Antarctic stations study a mixture of Antarctic and coastal air-masses. This study will be conducted at the important French/Italian ice-core drilling site at Dome C, located on the Antarctic plateau. Thus, the second aim of this work is to investigate the effect of air-snow chemistry on chemical records in ice cores used to infer previous climates. The proposed study is novel and excellent for three reasons: 1) The international team is investigating the snowpack chemistry AND the atmospheric chemistry. Many previous studies have tended to concentrate on the atmosphere, 2) The variation with depth of chemicals such as nitrate trapped in Antarctic ice cores potentially provides the strongest evidence available for past climate and climate change events, an understanding of which is required for the accurate predictions of future climate change. Deciphering the chemical signals present in the ice cores is a major challenge as various processes can lead to the loss of chemicals from the ice core after initial deposition. We propose to develop a method by which the nitrate profiles recorded in ice cores can be used to obtain oxidising capacity in past atmospheres. 3) The snow and ice at Dome C are not seasonal (no summer melting). This will be the first opportunity to measure photochemistry in snowpacks for non-seasonal snow and will be different to all previous work. The requested NERC support in this proposal is for the optical properties (albedo and light penetration depths of the Dome C snowpack to be measured, to monitor downwelling atmosphere radiation and the construction of a photochemical radiative transfer model to calculate photolysis rates of chemicals in the snowpack and fluxes of chemicals (NO, NO2, HONO etc) from the snowpack. This is a critical part of the international campaign which has British Antarctic survey (BAS) scientists measuring fluxes of these chemicals from the snowpack and three groups of French scientists measuring the snow microphysical structure, oxidants in the atmosphere and isotopic values of N and O in the snow and atmospheric modelling to explore the response of coastal stations to the interior oxidation chemistry as the air is transported away from the plateau to the coastal stations. The campaign is excellent value for money as the French Polar program IPEV is providing paid logistics. The proposal allows UK scientists access to the Antarctica Plateau, where the UK has no stations. This is a fantastic opportunity. The project partners are all world leading polar scientists. The campaign is an International Polar Year campaign under the International Global Atmospheric chemistry program (IGAC), AICI (air-ice chemical interactions) project.

Microscopic organisms in the ocean called phytoplankton use the sun's energy to convert carbon dioxide (CO2), nutrients and water into organic matter, just as plants do on land. This organic matter is grazed upon by tiny animals called zooplankton that are found throughout the global ocean. Marine zooplankton are so abundant that the total weight of their global population greatly exceeds that of the ~8 billion humans alive on Earth today. Like all animals, zooplankton produce vast quantities of faecal matter that they eject into the surrounding environment. Some of this waste sinks down into the abyss, carrying with it carbon that was once in the atmosphere as CO2. Any faecal carbon that reaches the deep ocean may be locked away down there for 100's or even 1000's of years. The process of exporting carbon in this way occurs on such a scale that it plays a fundamental role in global climate regulation, keeping our planet cool by slowing the rate at which CO2 accumulates in our atmosphere. Zooplankton are cold-blooded, and as such, their physiological rates increase as their environment warms. By contrast, the body size of zooplankton decreases with warming, although the mechanism underlying this phenomenon remains uncertain. Indeed, there are many gaps in our understanding of how temperature affects zooplankton physiology. For example, does the rate at which they can capture food increase at the same rate at which their demand for energy increases with warming? If it does, perhaps they will simply eat their way out of the climate crisis? But what if it doesn't? Continued ocean warming may then result in zooplankton having to use more and more of their food to meet the temperature-driven increase in their energy demands, leaving less and less for growth and reproduction. Does this situation get worse if the amount of food available to zooplankton decreases with ocean warming? And do different sized individuals respond differently to temperature? Our incomplete understanding of the interplay between temperature, food supply and zooplankton body size means that we cannot reliably predict their response to ocean warming. Indeed, most global models of the ocean ecosystem that are used to help predict future climate assume that these aspects of zooplankton physiology are fixed, with no sensitivity to warming. We therefore have only limited confidence in our ability to forecast how the zooplankton contribution to global climate regulation via ocean carbon storage will change as the ocean warms throughout the 21st century. Our project, C-QWIZ, will determine how zooplankton of different sizes respond to increasing temperatures at different levels of food. In doing so, we will fill many of the knowledge gaps in our fundamental understanding of their physiological response to climate change. The C-QWIZ team is uniquely placed to translate this new understanding into existing mathematical models of the global ocean ecosystem; we will be the first to mechanistically assess how global warming affects zooplankton-mediated ocean carbon storage throughout the 21st century. Our chosen model is used by scientists around the world to forecast how Earth's future climate will change. These forecasts are used by politicians and policy makers to decide on how best to manage the future of our planet. Improving these models therefore ensures that our science delivers real and lasting change for the benefit of all society.

The Arctic is a region experiencing rapid climate changes. APPOSITE is a proposed three year research programme focusing on improving our ability to forecast the climate of the Arctic on seasonal to inter-annual timescales. Arctic predictions would be of great value to both the people that live and work in the Arctic regions and also for informing important policy decisions about the region. Additionally, the Arctic region exerts an influence on the climate outside the Arctic. Hence improved forecasts of Arctic climate may increase our ability to forecast climate in mid-latitude regions, such as Europe, on similar seasonal to inter-annual timescales. Building such Arctic forecast systems will be a complex task, involving the construction of a detailed observation system to monitor Arctic climate, and sophisticated forecast models that can use these observations to enhance predictive capabilities. An important first step before committing to such a programme, is to assess the likely benefits that such a system may bring. APPOSITE is specifically designed to provide this assessment by answering four key questions: 1) What aspects of Arctic climate can we predict? 2) How far in advance can we predict these aspects? Does this depend on the season? 3) What physical processes and mechanisms are responsible for this predictability? 4) What aspects of forecast models should be prioritised for development? APPOSITE will use state-of-the art climate models to answer these questions. The answers to these questions will form a key part of the future development of seasonal to inter-annual Arctic forecasting systems nationally and internationally.

Climate science demands on data management are growing rapidly as climate models grow in the precision with which they depict spatial structures and in the completeness with which they describe a vast range of physical processes. For the Climate Model Inter-comparison Project 5 (CMIP5), a distributed archive is being constructed to provide access to what is expected to be in excess of 10 Peta-bytes of global climate change projections. The data will be held at 30 or more computing centres and data archives around the world, but for users it will appear as a single archive described by one catalogue. In addition, the usability of the data will be enhanced by a three-step validation process and the publication of Digital Object Identifiers (doi) for all the data. For many users the spatial resolution provided by the global climate models (around 150km) is inadequate: the CORDEX project will provide data scaled down to around 10km. Evaluation of climate impacts often revolves around extremes and complex impact factors, requiring high volumes of data to be stored. At the same time, uncertainty about the optimal configuration of the models imposes the requirement that each scenario be explored with multiple models. This project will explore the challenges of developing a software management infrastructure which will scale to the multi-exabyte archives of climate data which are likely to be crucial to major policy decisions in by the end of the decade. Support for automated processing of the archived data and metadata will be essential. In the short term goal, strategies will be evaluated by applying them to the CORDEX project data.