The impact of a rapidly shifting sea-ice cover on climate, ecosystem processes and biophysical habitat properties is not yet fully understood, particularly in the central Arctic Ocean, due to a lack of spatially representative observations. From June to July 2020 during the year-long Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC, leg 4) in the Transpolar Drift, we ...

To establish a management plan for northern shrimp (Pandalus borealis) in the Barents Sea, the Norwegian-Russian Fisheries Commission requested in 2023 a proposal for a harvest control rule (HCR). Based on discussions with stakeholders, six different HCRs were defined and evaluated against three performance criteria: 1. precautionarity (less than 5% risk of falling below limit reference point for ...

Cold-water lakes situated in high latitudes and altitudes have pivotal socio-ecological importance both globally and locally. However, they are increasingly threatened by multiple anthropogenic stressors, such as climate change, hydropower and invasive species. The development of efficient management strategies is therefore urgently needed and requires a comprehensive understanding of the factors ...

Coastal and adjacent shelf waters are generally highly productive ecosystems harboring important ecological processes and exposed to a range of anthropogenic pressures from land-based and marine sectors. Ensuring that the cumulative pressures from human activities do not cause unacceptable, permanent harm to the ecosystem is challenging but crucial for sustainable management of these regions. ...

Marine-terminating glacier fjords play a central role in the transport of oceanic heat toward ice sheets, regulating their melt. Mixing processes near glacial termini are key to this circulation but remain poorly understood. We present new summer measurements of circulation and mixing near a marine-terminating glacier with active sub-glacial discharge. 65% of the fjord's vertical overturning circulation ...

We report the effects of varying physiological and other properties on the heat and water exchange in the maxilloturbinate structure (MT) of the bearded seal (Erignathus barbatus or Eb) in realistic environments, using a computational fluid dynamics (CFD) model. We find that the water retention in percent is very high (about 90 %) and relatively unaffected by either cold (−30 ◦C) or warm (10 ◦C) ...

On Arctic shelves, benthic food-webs are tightly linked to overlying primary production. In the seasonal ice zone, sympagic (ice-associated) primary production can be a major source of carbon for the benthos on productive inflow shelves. However, the role of sympagic organic matter is less well-understood in food webs of heavily ice-covered, less- productive outflow shelves, such as the northeast ...

In mammals, seasonal opportunities and challenges are anticipated through programmed changes in physiology and behavior. Appropriate anticipatory timing depends on synchronization to the external solar year, achieved through the use of day length (photoperiod) as a synchronizing signal. In mammals, nocturnal production of melatonin by the pineal gland is the key hormonal mediator of photoperiodic ...

The microbial diversity associated with terrestrial groundwater seepage through permafrost soils is tightly coupled to the geochemistry of these fluids. Terrestrial alkaline methane seeps from Lagoon Pingo, Central Spitsbergen (78°N) in Norway, with methane-saturated and oxygen-limited groundwater discharge providing a potential habitat for methanotrophy. Here, we report on the microbial community’s ...

Microalgae are the main source of the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), essential for the healthy development of most marine and terrestrial fauna including humans. Inverse correlations of algal EPA and DHA proportions (% of total fatty acids) with temperature have led to suggestions of a warming-induced decline in the global production of these biomolecules ...