The Changing Arctic Ocean Seafloor (ChAOS) - how changing sea ice conditions impact biological communities, biogeochemical processes and ecosystems

ChAOS will quantify the effect of changing sea ice cover on organic matter quality, benthic biodiversity, biological transformations of carbon and nutrient pools, and resulting ecosystem function at the Arctic Ocean seafloor. We will achieve this by determining the amount, source, and bioavailability of organic matter (OM) and associated nutrients exported to the Arctic seafloor; its consumption, transformation, and cycling through the benthic food chain; and its eventual burial or recycling back into the water column. We will study these coupled biological and biogeochemical processes by combining (i) a detailed study of representative Arctic shelf sea habitats that intersect the ice edge, with (ii) broad-scale in situ validation studies and shipboard experiments, (iii) manipulative laboratory experiments that will identify causal relationships and mechanisms, (iv) analyses of highly spatially and temporally resolved data obtained by the Canadian, Norwegian and German Arctic programmes to establish generality, and (v) we will integrate new understanding of controls and effects on biodiversity, biogeochemical pathways and nutrient cycles into modelling approaches to explore how changes in Arctic sea ice alter ecosystems at regional scales.
We will focus on parts of the Arctic Ocean where drastic changes in sea ice cover are the main environmental control, e.g., the Barents Sea. Common fieldwork campaigns will form the core of our research activity. Although our preferred focal region is a N-S transect along 30 degree East in the Barents Sea where ice expansion and retreat are well known and safely accessible, we will also use additional cruises to locations that share similar sediment and water conditions in Norway, retrieving key species for extended laboratory experiments that consider future environmental forcing. Importantly, the design of our campaign is not site specific, allowing our approach to be applied in other areas that share similar regional characteristics. This flexibility maximizes the scope for coordinated activities between all programme consortia (pelagic or benthic) should other areas of the Arctic shelf be preferable once all responses to the Announcement of Opportunity have been evaluated.
In support of our field campaign, and informed by the analysis of field samples and data obtained by our international partners (in Norway, Canada, USA, Italy, Poland and Germany), we will conduct a range of well-constrained laboratory experiments, exposing incubated natural sediment to environmental conditions that are most likely to vary in response to the changing sea ice cover, and analysing the response of biology and biogeochemistry to these induced changes in present versus future environments (e.g., ocean acidification, warming). We will use existing complementary data sets provided by international project partners to achieve a wider spatial and temporal coverage of different parts of the Arctic Ocean. The unique combination of expertise (microbiologists, geochemists, ecologists, modellers) and facilities across eight leading UK research institutions will allow us to make new links between the quantity and quality of exported OM as a food source for benthic ecosystems, the response of the biodiversity and ecosystem functioning across the full spectrum of benthic organisms, and the effects on the partitioning of carbon and nutrients between recycled and buried pools. To link the benthic sub-system to the Arctic Ocean as a whole, we will establish close links with complementary projects studying biogeochemical processes in the water column, benthic environment (and their interactions) and across the land-ocean transition. This will provide the combined data sets and process understanding, as well as novel, numerically efficient upscaling tools, required to develop predictive models (e.g., MEDUSA) that allow for a quantitative inclusion seafloor into environmental predictions of the changing Arctic Ocean.

ChAOS has the potential to generate impact, beyond the academic community, that will benefit a number of groups or organisations:

The major deliverables of ChAOS will be of direct relevance to stakeholders with an interest in Arctic marine ecology and multiple use of the benthic environment. We will target beneficiaries at a range of levels, in particular 'hard to reach groups' from different local communities. Engagement with stakeholders and beneficiaries will be overseen by the module leaders, and co-ordinated fully by PI Maerz and Communication Officer Kate Lock (Leeds). We will hold an early impact meeting at the start of the grant for all consortium members, in order to co-ordinate our efforts across the entire research group.

At the community level, we will focus on reaching indigenous people, local councils, and regulatory bodies (in the UK and Arctic countries), who will benefit from a greater understanding of the sustainable and multiple use of the seafloor. On national levels, we will communicate directly with government organisations DEFRA and CEFAS to ensure our project outcomes directly inform political decision making in the UK. We will also engage with national organisations within the Arctic countries, including the Arctic Monitoring and Assessment Programme (AMAP, a working group of the Arctic Council); Protection of the Arctic Marine Environment (PAME) and MAREANO. We will also forge links with the commercial and industrial sector - via official bodies both in the UK, such as the Renewable Energy Association, and in Arctic nations, such as working groups of the Arctic Council - and non-government organisations such as the World Wildlife Fund. We will form an Advisory Committee that consists of representatives from all of the government, industry and NGO stakeholders, which will meet twice yearly including a virtual link up to Arctic partners, and we will host a stakeholders' workshop towards the end of the project at the University of Leeds. We will encourage PhDs and postdocs to attend the NERC policy placement fellowship scheme.

We will engage with members of the public, in particular 'hard to reach' sectors of the community through exploring partnerships with dedicated organizations, such as the Active Learning Partnership. Public outreach will be led by a Communications Team who will focus on the broader importance of understanding future impacts on Arctic ecosystems. Firstly, we will involve project participants through direct communication with the public, through school visits and by participation on national and local events (e.g. Pint of Science, Soapbox Science, Royal Society events). Secondly, we will work with an experienced science journalist, Helen Scales, to produce a radio documentary and features for national and international magazines and websites, in order to broaden our audience further. We will build on successful programme sites (e.g. NERC Planet Earth) to promote our outreach products from the stakeholders' workshop and other meetings, and will publicise our events through social media.

All students, PDRAs and early career researchers across the consortium will be encouraged to undertake training in engagement and science communication activities, and take part in work shadowing of more established colleagues. The Communication Officer will work closely with each institute to monitor and ensure timely delivery of outreach, effective impact and assessment of feedback, assisted by the early career researchers on the project.