This plenary session provides an overarching, cross-disciplinary picture on central processes taking place on the Arctic inflow shelf seas, the Arctic interior and outflow shelf seas, and in the deep central Arctic Ocean. This plenary provides an introduction to the afternoon parallel session on inflow shelves (session D), interior and outflow shelves (session E), and in the central Arctic Ocean (session F).
Session chair: Sebastian Gerland
09:00-09:30 Keynote Talk 3: Characteristics and Composition of Sea Ice in the Central Arctic Ocean Marcel Nicolaus (Alfred-Wegener-Institute, Germany)
09:30-10:00 Keynote Talk 4: Freshwater Impacts on the Arctic Ocean Carbon Cycle, Views from Multiple Scales Kristina Brown (University of Manitoba, Canada)
10:00-10:30 Keynote Talk 5: Benthic Systems in Pacific and Atlantic Sectors of the Arctic Ocean Monika Kędra (Institute of Oceanology Polish Academy of Sciences, Poland)
11:30-11:45 Plenary Talk 7: Microbial Communities in the Future Central Arctic Ocean – What can We Learn from Present Observations and What’s Next? Oliver Müller (University of Bergen, Norway)
11:45-12:00 Plenary Talk 8 Science for use talk Ecosystem Modelling to Support Ecosystem-Based Management in the Barents Sea, Now and in the Future Benjamin Planque (Institute of Marine Research, Norway)
All Nansen Legacy researchers still actively involved in the project should purchase their travel as they have done previously (follow guidelines at their own institution) and apply for travel reimbursements by their respective partner institutions. The institutions will then send a compiled claim to the project office.
For symposium registration, the project administration will soon send you a booking code by email that will allow you to register for the symposium and book the hotel room through the registration system. Accommodation costs and the participant fee will directly be covered by the Nansen Legacy.
Plenary Talk 8
Wednesday, 8 November 2023 11:45-12:00
- Science for use talk -
Ecosystem modelling to support ecosystem-based management in the Barents Sea, now and in the future
Benjamin Planque (Institute of Marine Research, Norway)
Conventional fisheries management relies on models that estimate how fish populations have changed in the past and how they might change in the future. The transition to ecosystem-based management has shifted towards considering multiple factors such as how different species interact, and how climate change and multiple human activities (e.g., fishing, shipping, tourism, energy) affect ecosystems and the services they provide. To support this approach, new models are needed that can consider all these dimensions together (rather than just considering one or few species at a time). While ecosystem models have been around for a while, they are not yet widely used in management. In this presentation, I will discuss existing ecosystem models and how they are, or can be, used in ecosystem-based management. I will also talk about some of the challenges that need to be addressed to make these models more useful. Finally, I will suggest how models can be developed to better support management in the future.
Plenary Talk 7
Wednesday, 8 November 2023 11:30-11:45
Microbial communities in the future central Arctic Ocean – what can we learn from present observations and what’s next?
Oliver Müller (University of Bergen, Norway)
With its large interannual differences in ice extent, the Barents Sea is the ideal large-scale simulator to investigate how the Arctic marine ecosystem will respond to reduced sea-ice cover. By connecting seasonal studies in the Barents Sea (Nansen Legacy) with a year-long drift through the central Arctic Ocean (MOSAiC) we will reveal new insights on important microbial processes in the Arctic, how they differ from our expectations and set them into historical context (Nansen`s Fram expedition). We have focused on measurements of microbial abundance, including virus, bacteria and small phytoplankton and activity measured as bacterial production and our results clearly demonstrate the importance of sea ice in structuring microbial communities as response on phenological variability in primary production. To better understand the consequences of an ice-free future for Arctic microbial communities, we need to improve our knowledge on how sea ice is affecting microbial processes and whether our current paradigms on seasonal processes are more complex than previous thought. We need to compare our present observations with the past, e.g. by use of ancient DNA, to disentangle whether the new knowledge is a result of improved measurements or of a changed Arctic.
Plenary Talk 6
Wednesday, 8 November 2023 11:15-11:30
Importance of sea-ice - atmosphere interactions for kilometer-scale weather prediction
Malte Müller (Norwegian Meteorological Institute, Norway)
The development of coupled Earth modeling systems on a kilometer-scale resolution is a new frontier for operational forecasting. However, accurately representing interactions between the atmosphere, snow/sea-ice, ocean, and waves is challenging due to the complexity of interactive mechanisms, the limited accuracy of the model components, and the availability of observations to resolve and assess relevant coupled processes. An overview of recent work will be given to assess the sensitivities of the model system to the representation of the sea-ice and snow by utilizing a multitude of observations, including field-campaign data, as well as satellite retrievals and standard in situ observations.
Plenary Talk 5
Wednesday, 8 November 2023 11:00-11:15
Large-scale atmospheric drivers of Barents Sea climate variability
Camille Li (University of Bergen, Norway)
The Barents Sea sits in the main corridor of travelling weather systems, steered by the atmospheric jet stream, that carry warm air and moisture from the North Atlantic towards the Arctic. As such, conditions in the Barents are sensitive to factors that influence the speed, position and path of the jet. At the same time, ocean-driven changes in sea surface temperatures and sea ice cover may be felt by the atmosphere, with the possibility of teleconnections communicating these signals to other parts of the globe. Using observational and modelling results, this presentation will give an overview of how the atmosphere drives variability and change in the Barents region, and whether the Barents can affect climate and weather further afield. Open questions concerning the ability of climate models to capture the relevant processes and the implications for constraining future change in the region will be explored.
Keynote Talk 5
Wednesday, 8 November 2023 10:00-10:30
Benthic systems in Pacific and Atlantic sectors of the Arctic Ocean
Monika Kędra (Institute of Oceanology Polish Academy of Sciences, Poland)
Arctic marine benthos and their food webs play an important role in overall ecosystem functioning including production and organic matter and energy cycling. Benthic organisms are considered temporal couplers of resources, especially in ecosystems with strong seasonality and seasonal organic matter pulses to the sea floor. In the Arctic predicted changes in primary production patterns are expected to impact pelagic-benthic coupling processes, and thus benthos and their food webs, and thus whole ecosystem functioning. In this talk I review and compare the benthic communities and their functioning in the Pacific and Atlantic sectors of the Arctic Ocean. I discuss the responses of benthic organisms and their trophic relations to the on-going and predicted changes in the quality and quantity of organic matter delivered to the sea floor. Potential consequences of possible changes in benthic communities for the ecosystem functioning are considered.
Keynote Talk 4
Wednesday, 8 November 2023 09:30-10:00
Freshwater impacts on the Arctic Ocean carbon cycle, views from multiple scales
Kristina Brown (University of Manitoba, Canada)
Unprecedented rapid changes in the Arctic Ocean are impacting its coupled physical and biogeochemical systems. Sea ice loss, together with increases in river input and coastal erosion, are altering both the Arctic’s freshwater system and its carbon cycle in tandem. Such ongoing changes will play an important role in the global climate system, in particular impacting the Arctic Ocean’s ability to act as a CO2 sink for atmospheric CO2. In this talk I will look at the impact of freshwater on the Arctic Ocean carbon cycle at a variety of scales to address the core question, “how does freshwater impact CO2 exchanges in the surface ocean?”. At the pan-Arctic scale, I discuss the dual roles of regionality and seasonality of freshwater sources in establishing the backdrop for the biogeochemical processes that constrain carbon cycling in the surface ocean. Then I narrow the view to the regional frame, presenting new insights about the smaller northern rivers that drain the Arctic coastal margins. Lastly, I will discuss some of the challenges to freshwater and carbon monitoring in local river systems to demonstrate where community supported observational projects have been successful in filling critical gaps. Looking at this question from multiple perspectives allows us to see the importance of scalability in the design of observation systems and the absolute necessity for partnerships with northern communities to meet the challenges of Arctic research.
Keynote Talk 3
Wednesday, 8 November 2023 09:00-09:30
Characteristics and composition of sea ice in the central Arctic Ocean
Marcel Nicolaus (Alfred-Wegener-Institute, Germany)
Arctic sea ice has decreased in extent and thickness during all seasons. The ice cover changed to a younger and more seasonal ice pack with different physical properties. However, it is still challenging to characterize sea ice and snow properties and processes during all seasons in relation to feedbacks with the atmosphere and the ocean. As a result, numerical simulations and forecasts as well as satellite data retrieval algorithms still have large uncertainties. During the Multidisciplinary drifting Observatory for the Study of Arctic Climate, MOSAiC, sea ice and snow properties were observed over a full annual cycle in 2019/2020. In this presentation, I will summarize and review the sea ice and snow conditions over the annual cycle based on MOSAiC results. I will present mean properties of key parameters ranging from the lowest atmosphere, through snow and sea ice, into the upper ocean. The results indicate that the contrasts of different sea ice types in the Arctic Ocean diminish from autumn to spring. New sea ice types, pressure ridges and snow distributions need to be considered more explicitly when describing and modelling atmosphere-ice-ocean interactions. This will help to improve our understanding of the coupled Arctic system and lead to improved forecasts.
