Written by Professor Rolf Gradinger, Department of Arctic and marine biology.
Barents Sea ecosystems supports one of the most economically valuable fisheries on Earth. But the high latitudes are changing drastically with the climate changes. It is uncertain if and how the future Barents Sea will function in the future. Will food web interactions change and current species disappear and be replaced by other taxa? This challenging question is the major focus of the Norwegian Arven etter Nansen project supported by other ongoing research.
In May 2021, the research and education network ARCTOS teamed up with Arven etter Nansen to investigate the biology in the dynamic frontal zone between Arctic and North Atlantic water masses in the so-called Polar Front region east of Svalbard. During the 11-day long expedition onboard Helmer Hansen (a UiT research vessel), we did not only conduct cutting edge research but also provided a framework for education of early career scientists as part of the UiT course BIO-8510.
Study area and station map of the ARCTOS-AeN Polar Front study (ARCTOS).
The expedition crossed the Polar Front twice and collected samples. We wanted to explore and understand the distribution patterns and activity of plankton, fish, seafloor living creatures, marine mammals, and relate these patterns and their activities to how this frontal zone was structured. Was it just a boundary, separating Arctic from Atlantic domains and species? Or does it have unique dynamics leading to e.g., enhanced food availabilities to sea birds and marine mammals creating an oasis in the desert?
In addition to the use of traditional sampling devices , we used innovative new tools. These new tools were two gliders and two sailbuoys (sponsored by Equinor) and fast repetition rate fluorometers. They provide insights into both the small-scale distributions and physiology and broad-scale distributions of marine organisms which is not possible to be assessed with normal ship-board instruments. Sea ice limited our ability to trawl and use gliders in the northern part of the Polar Front, but provided us with a short insight into the life of two polar bears. The crew of Helmer Hanssen provided us with outstanding support to our many wishes, not minding the frequent adjustments of the scientific program.
Our first results show that we sampled a well-developed frontal system with clear separation of Arctic and Atlantic water, combined different community patterns on all trophic levels. We also encountered an exceptionally strong microalgal spring bloom, dominated by millions of diatom microalgae in the water column. Further conclusions must wait now for the data analyses which are currently conducted and will be summarized at the upcoming AeN annual meeting, and a dedicated Polar Front workshop end of this year.
Examples of microalgal species encountered during the expedition (R. Gradinger).
The PhD level teaching component (BIO-8510), organized through ARCTOS and UiT, attracted 15 early career scientists from Norwegian, UK and US universities. They had widely ranging interests, from remote sensing, ocean physics to marine mammal acoustics. All students participated in research programs, whether it was algal activity measurements or the study of benthic macrofauna. Participating senior researchers came from Akvaplan-niva, NINA, and UiT. This experience provided the students with a unique training in Arctic Systems Science, a holistic view looking at interconnections between different components of the living and non-living parts of the Barents Sea. Without the excellent student engagement, their energy and commitment, this expedition would not have been able to achieve the broad scientific success that we had. Although the course has officially ended, the participating students have been invited to be involved in future sample analyses, data processing and manuscript writing.
Students analysing zooplankton samples (R. Gradinger).
The cruise participant nationalities included Brazil, Canada, China, Cyprus, Denmark, France, Finland, Germany, Iran, Norway, Pakistan, Philippines, Switzerland, UK, and USA. The combination of home institutions and diversity of nationalities allowed all participants to further build their networks of scientific connections and culture experiences – both important attributes for successful career and personal growth.
Celebrating May 17, 2021 onboard Helmer Hanssen (ARCTOS).
To make reasonable predictions is a task given rightfully to us scientists from the public. Such predictions can only be as good as the data that are used to develop them. Only field-going research like this AeN and ARCTOS partnership can solve the puzzle how the future Barents Sea will work, and if it will continue to sustain one of the most economically important fisheries on Earth. Therefore, information from our cruise is critical as the Barents Sea is a sea in change, driven by multiple human stressors. This research will continue as we in an ARCTOS consortium were just awarded funding from the Norwegian Research Council (in cooperation with Equinor and Conoco Philips) to continue our Polar Front research through further seasonal research cruises and extended science missions with May 2022 as next targeted time window, again together with BIO-8510.
Further reading:
En reise til det kjente ukjente.
Fyrstehandserfaring om bord FF Helmer Hanssen.
Der det varme Atlanterhavsvannet møter Arktisk kulde.
ARCTOS-Nansen Legacy Polar Front cruise.
Where the Atlantic heat meets the Arctic Cold.
Departure into the known unknown.
First experience onboard the RV “Helmer Hanssen”.
Life at the seabed: studying bottom-dwelling fish and invertebrates across the polar front.
