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.
Khuong V. Dinh (University of Oslo, Norway)
Global warming, marine heatwaves, and ocean acidification can affect physical and ecological processes in Arctic marine ecosystems. These processes can have knock-on effects on the uptake, fate, and effects of persistent organic pollutants and contaminants of emerging Arctic concern in Arctic marine organisms. Conversely, toxicant exposure can affect species’ adaptability to climate change. Here, we have summarized how climate change affect physical and ecological processes in Arctic marine biota and food webs.
1) Global use and regulations of pollutants still are the main drivers for levels in Arctic biota, increased incidents of positive states of the North Atlantic Oscillation (NAO+) result in the increased long-range transport of pollutants and biomagnification in Arctic food webs.
2) Northward range‐shifting species act as biovectors for pollutants into Arctic marine food webs, leading to elevated levels.
3) Dietary shifts can alter pollutant transfer in the food webs. Reductions in body condition are associated with pollutant increase in some biota.
4) The interaction of warming, ocean acidification and pollutants can result in antagonistic, additive or synergistic effects depending on the species, life stages, and the magnitude and duration of stressor exposure. Furthermore, multiple stressors studies have predominantly been conducted during summer months, however, we show that we show that effects and interactions of these stressors can often differ between winter and other seasons.
Studies that are performed across a series of stress levels, exposure conditions in multiple seasons will be particularly important to tease apart the effects of climate change on pollutant toxicity and accumulation. A step further is to identify the ecological tipping points of Arctic marine species and food webs in complex interactions of climate change and pollutants, which are crucial for more comprehensive ecological risk assessments and management.
Christian März (University of Bonn, Germany)
Marine sediments are excellent recorders of past environmental conditions – but they are also biogeochemical reactors. This “duality” presents a challenge for paleo-environmental reconstructions: On the one hand, certain sediments are more prone to diagenetic overprint than others – on the other hand, certain depositional conditions give rise to more intense diagenetic reactions. Within the NERC-funded project ChAOS (The Changing Arctic Ocean Seafloor), and in collaboration with the Nansen Legacy project, an interdisciplinary team of scientists studied the shallow seafloor of the Barents Sea to unravel the diagenetic processes occurring in these deposits, and to inform paleo-environmental reconstructions on sediment cores from this Arctic shelf region. In this talk, I will present an overview of our findings, focusing on factors that control the degradation/dissolution versus preservation of various sediment components, including organic matter, biogenic carbonate, biogenic opal and metals like iron and manganese.
Maxime Geoffroy (Memorial University of Newfoundland, Canada)
The Arctic is warming up to four times faster than the rest of our planet, resulting in a drastic reduction in sea ice cover and an increase in water temperatures. These changes strongly modify the habitat of the fish thriving under the extreme conditions prevailing in the Arctic and allow boreal species from the North Atlantic and Pacific to migrate further North, potentially opening new fishing grounds. However, these changes do not occur at the same rate across all Arctic regions. The Canadian Arctic remains mostly dominated by endemic species, while the Barents Sea experiences a rapid borealization of its fauna. Based on acoustic-trawl surveys conducted in both regions, this presentation will contrast the diversity and distribution of fish in the Canadian Arctic and the Barents Sea. It will further discuss current and future changes in their fish and fisheries ecosystems.
Janne Søreide (University Centre in Svalbard, Norway)
One of the distinct features of the European Arctic is the massive influx of warm Atlantic water, carrying huge amounts of nutrients and boreal plankton north. The result is a diverse and rich zooplankton community in the Svalbard-Barents Sea region, where a dominance of North Atlantic species mirrors strong influence of Atlantic water. The continuous supply of boreal zooplankton exposes the European Arctic zooplankton community to a severe borealisation, also referred to as “Atlantification”. However, the long, dark winter combined with the short summer make it hard for most of these boreal species to survive and thrive and we observe a reset to a more Arctic zooplankton community over the course of the winter. With global warming, sea ice extent and thickness are reduced while the primary production season in the high Arctic is extending. Whether this will increase survival rate and reproductive success of boreal species in the European Arctic is one of the key questions that will be discussed in this talk.
Karley Campbell (University of Tromsø The Arctic University of Norway, Norway)
Primary producers are the basis of ecosystems. Through their photosynthetic activity they provide the organic carbon necessary to support higher trophic levels while also influencing the movement of climate relevant gases like CO2 between the atmosphere and ocean. In the Arctic, sea ice is a prominent yet rapidly changing feature of the marine ecosystem that both hinders photosynthetic activity and provides new habitat opportunities. Here we review the current distribution of - and ongoing changes to - primary producers and their production in the Arctic Ocean. Important considerations for studying the production potential of sea ice are also investigated; including the need to represent a diversity of microhabitats within the ice and consider the role of respiration associated with them.
Igor V. Polyakov (University of Alaska, Fairbanks, USA)
High-latitude atlantification is caused by increased warm, salty sub-Arctic inflows, which affect oceanic stratification, increase heat fluxes, and decrease sea ice in the Eurasian Basin of the Arctic Ocean. These inflows from the North Atlantic across the Nordic Seas are modulated by the atmospheric Arctic Dipole (AD), linked with anticyclonic winds over North America and cyclonic winds over Eurasia. The alternating atmospheric AD regimes establish a "switchgear mechanism". Switchgear decreased northward inflows across Fram Strait and increased inflows throughout the Barents Sea between 2007 and 2021, which was connected with the positive AD regime. A stronger Arctic Ocean circulation and freshwater redistribution into the Amerasian Basin associated with increased stratification and decreased oceanic heat fluxes are other consequences of the positive AD regime. These processes contributed to a hiatus in Arctic sea-ice loss after 2007. A transition to a new negative AD regime will likely accelerate the Arctic sea-ice decline, with consequences for the Arctic climate system.