Biological nitrogen fixation is considered the major input of reactive nitrogen in low latitude open ocean regions, fuelling primary productivity and carbon export. For decades, nitrogen fixation had been assumed to be absent in the temperate shelf seas and high latitude ocean. However, there is now growing evidence that nitrogen-fixers are active in these systems, but the magnitude, environmental drivers, players and ecological implications are poorly known. This evidence is accumulating at a time when these systems are rapidly changing, underscoring the need for a focused effort in the scientific community to accelerate understanding of nitrogen fixation beyond the low latitudes. Compared to open oceans, temperate shelf and high latitude regions are heterogeneous and highly dynamic, limiting observations and challenging modelling efforts. Current models that include nitrogen fixation parametrise the geographical extent as a function of reactive nitrogen and/or temperature, excluding cold and nutrient-rich temperate shelf and high latitude oceans. This workshop aims to bring together the communities working on modelling nitrogen fixation with those of the physical oceanography, biogeochemical and molecular observational communities to identify the data types and mechanistic understanding needed to parametrise nitrogen fixation beyond low latitude regions. Our aspiration is to identify the path forward to further develop models that incorporate nitrogen fixation in temperate shelf and high latitude oceans, to enable quantifying its contribution to the global nitrogen inventory, hypothesis testing and forecasting changes in nitrogen fixation in the future ocean.

The Author of this Article Mar Benavides (National Oceanography Centre)

More than 30 BIOPOLE scientists, in person or online, took part in the BIOPOLE II cruise planning meeting on 11^th Nov at the British Antarctic Survey. The cruise (SD046) will be on board the Sir David Attenborough and will be led jointly by Geraint Tarling and Sophie Fielding of BAS. It will sample large areas of the Scotia and Weddell Sea in the Southern Ocean during February and March, 2025. SD046 is deliberately timed to be in the late summer to autumn period when there is a large seasonal migration of mesozooplankton into deep ocean layers, where they overwinter. It is during this time that many are likely to be washed onto the banks of continental shelves to be predated on by organisms living on the seabed.  All of these processes are key to the sequestration of atmospheric carbon into the deep ocean. 

During the cruise meeting, Geraint and Sophie firstly outlined the general plan, highlighting the three distinct phases of the cruise (see map above), the first focussing on the South Georgia region (phase SG), the second, a long transect in the eastern Scotia Sea (phase A23) and the third, sampling in the Weddell Sea, particularly the South Orkneys and Powell Basin (phase BP). There will be a different emphasis to the sampling plans in each of these three phases, although all will involve sampling plankton and seabed organisms and measuring the physical and biogeochemical properties of the water.  

There followed presentations from each of the science disciplines taking part, including ocean physics, biogeochemistry, phytoplankton, zooplankton, krill, benthic communities, and higher predators/marine mammals. This led into breakout groups considering water sampling protocols, the use of controlled temperature rooms and approaches to higher predator monitoring. The meeting ended with a general discussion on how to prepare for life on board, how activities may differ between sampling stations, and further contingencies in the face of unknown factors such as the early advance of sea-ice over our intended sampling area. These matters, and others, were considered further in the more relaxed atmosphere of the Castle Pub later that evening. In all, a successful meeting and a good foundation on which to develop further plans for the cruise.  

The Author of this Article Geraint Tarling (British Antarctic Survey)

We’re thrilled to announce that BIOPOLE has expanded its online presence by joining Instagram and Bluesky! These platforms will allow us to connect with a broader community, share ground breaking research, and foster meaningful conversations about the Arctic, Antarctic, and the future of our planet. 

Follow us for updates, insights, and discussions that matter to scientists, activists, and anyone passionate about polar regions and global change. 

📲 Find us on Instagram: @biopole_nerc_nc 
🌐 Join us on Bluesky: @biopole.bsky.social 

Let’s shape the future of polar science together—see you online! 

Antarctic benthic ecological change – Huw Griffiths

“Antarctic benthic ecological change” is an invited review summing up our current knowledge of ongoing and future impacts of environmental change on the seafloor (benthic) animals and plants around Antarctica. The benthic community around Antarctica is diverse and highly endemic. These cold-adapted species are under threat from local and global drivers, including warming, acidification and changes to the cryosphere. We summarized observed, experimental and modelled Antarctic benthic ecological change. Warming, glacial melt and retreat, and reduced ice cover are causing regional benthic biomass to increase or decrease, depending on the additional influences of ice scour, turbidity and freshening.

Additionally, the dominance of previously cold-restricted or light-restricted species is increasing, and several ecological tipping points have already been breached, leading to ecological phase shifts in some habitats. The largest changes have been observed in communities in the shallows of the West Antarctic Peninsula, notably change to distribution, biodiversity, biomass and food webs. Models based on observational and experimental evidence indicate that these changes will spread deeper and eastwards throughout this century. Available data are primarily limited to a handful of shallow-water taxa; thus, future work will need to involve multispecies observations and experiments encompassing multiple drivers to understand community and ecosystem responses, and autonomous monitoring techniques to fill geographical, bathymetric, seasonal and taxonomic gaps; advances in environmental DNA and artificial-intelligence-based techniques will help to rapidly analyse such data.

The full paper may be (open) accessed here.   

The author of this article Huw Griffiths (British Antarctic Survey)

In the early morning of December 20th Kate Hendry (BAS) and Alanna Grant (CEH) boarded the British Antarctic Survey’s Dash 7 airplane at Punta Arenas airport to make the five-hour journey across the Drake Passage to the West Antarctic Peninsula. They were making their way to Rothera Research Station for the BIOPOLE project.

The overall aim of the BIOPOLE Rothera campaign was to assess the flux of organic and inorganic nutrients into Ryder Bay, the glaciated bay near Rothera Research Station. Kate and Alanna worked together in 2023 during the first BIOPOLE Svalbard fieldwork season, but faced very different conditions this time around off the West Antarctic Peninsula.

Whilst the northern fieldwork involved extensive river sampling, of glaciated and non-glacial river systems, the freshwater inputs into Ryder Bay are much harder to access. They’re hoping to be able to sample surface meltwater runoff later in the season, as the summer months progress, but in the meantime will be sampling seawater and using isotope geochemistry to unpick the meltwater contributions.

As well as characterising freshwater inputs, the team have been working with the Rothera Time Series (RaTS) project, together with Rothera Ocean Scientists Alice Clement and Sean McLoughlin, to sample marine waters within Ryder Bay. RaTS has been operating since 1997, and is an almost unique long-term observational dataset, especially important as data are collected year-round (not just in the Antarctic summer, when access is more straightforward).

The BIOPOLE fieldwork is being carried out in collaboration with NERC-funded project SiCLING. Kate will be joined by SiCLING team members later in January to carry out sampling of marine sediments and waters.

The BIOPOLE/SiCLING team would like to thank Allie and Sean (Rothera Ocean Scientists), and the rest of the marine team. Thanks also to everyone at Rothera Research Station for all their support.

The author of the article – Kate Hendry from British Antarctic Survey and Alanna Grant from UK Centre for Ecology & Hydrology

Rachael Sanders

• Please introduce yourself.  

My name is Rachael Sanders, I’m a postdoc in the Polar Oceans team at BAS. 

• Tell us about your professional and academic career before becoming part of the BIOPOLE Community. 

I completed my undergraduate degree at the University of Liverpool, where I studied maths with oceans and climate science, with a year also working at the National Oceanography Centre in Liverpool. After that, I moved to Cambridge to do a PhD with BAS and the University of Southampton, exploring drivers of interannual variability in Southern Ocean water masses, and particularly the impact of sea ice changes on Subantarctic Mode Water. Since then, I have completed two short postdocs; the first at BAS, where I investigated the causes of the 2015 North Atlantic cold anomaly within different ocean models. The second was at NORCE in Bergen, where I was developing a method to quantify different processes driving deoxygenation using observations from the North Atlantic.

• What do you do within BIOPOLE?  

I’m a physical oceanographer working in Work Package 1. I’m using measurements of oxygen isotopes from the Arctic and Southern Ocean to determine the fraction of water that originates from different sources. By looking at the ratio of different oxygen isotopes, along with the salinity of the water samples, it is possible to calculate how much of the freshwater originated from sea ice, compared to glacial melt and precipitation.

• What have you enjoyed about BIOPOLE so far? 

It’s really nice to be working with such a diverse group of people with different academic backgrounds.

• Tell us about a skill or trait unique to you that you would like to share? 

I’m not sure I have any particularly unique skills, but after asking around for ideas, I’ve been told that I keep morale high… although this is probably just because I organise weekly cake at work, forcing everyone to socialise.

Emma Young

• Please introduce yourself.  

I’m Dr Emma Young and I work as an ocean and biophysical modeller within the Polar Oceans team at the British Antarctic Survey. 

• Tell us about your professional and academic career before becoming part of the BIOPOLE Community. 

During my physics degree, I realised that although topics like quantum mechanics were fascinating, what really interested me were the more applied subjects, such as medical physics and meteorology. I went on to study atmospheric sciences and dabbled with the idea of hurricane research for a while, before I discovered the delights of ocean modelling during my dissertation, which I continued for my PhD. It was then that I discovered a love for interdisciplinary research, using ocean models to understand how oceanographic variability influences the transport and recruitment of marine organisms. After completing my PhD, I continued working on interdisciplinary modelling for 5 years at the Centre for Environment, Fisheries and Aquaculture Science (Cefas), where I also discovered that observational oceanography is definitely not for me – I’m not a good sailor. I then spent a few years at the Proudman Oceanography Laboratory (now NOC) before moving to the British Antarctic Survey where I continue to enjoy using ocean modelling for interdisciplinary research.

• What do you do within BIOPOLE?  

Within BIOPOLE, my work is contributing to WP1, 2 and 3, and I also co-lead the Modelling-Observations Working Group, which aims to encourage and enhance links between BIOPOLE modelling work and observational campaigns. As part of WP1, I’m adding tracers to a South Georgia regional ocean model to investigate how climate variability impacts the transport of nutrients from land and marine sources, and their export to the open ocean. My modelling work for WP2 and 3 focusses on the NW Weddell Sea region, using a combination of regional ocean modelling and particle tracking to investigate the transport pathways and benthic interactions of diapausing copepods. Diapausing copepods are important for carbon export to deeper waters but there’s a lot of uncertainty around the timing and depth of diapause, and the role of fine-scale ocean flows, which are not well represented in global models. The modelling I’m doing aims to address these uncertainties.

• What have you enjoyed about BIOPOLE so far? 

One of the things I’ve really enjoyed about BIOPOLE is the chance to meet and work with scientists from a wide range of disciplines. It’s great to hear about the diverse research being done by the BIOPOLE community across different institutes and I’ve enjoyed contributing to the project in unexpected ways, such as providing oceanographic information to support cruise planning.

• Tell us about a skill or trait unique to you that you would like to share? 

I love playing the piano and violin in my spare time. If I’ve had a particularly frustrating day failing to debug model code, attacking a Beethoven piano sonata provides instant stress relief (for me, if not for the rest of the household!).

Katrin Linse

• Please introduce yourself.

My name is Katrin Linse and I am a Senior Biodiversity Biologist at the British Antarctic Survey in Cambridge.

• Tell us about your professional and academic career before becoming part of the BIOPOLE Community. 

I joined BAS in 2000 after a PhD at the University of Hamburg, Germany. My research focusses on marine benthic invertebrates in polar and deep-sea environments, their biodiversity, phylogeography, ecology and evolution. At BAS, I led the biodiversity projects MARB, BIOPEARL and EvolHist and was/am a key UK member in ANDEEP, ChEsSO, IceAGE, IceDivA, and HEXPLORES discovering unexpected high biodiversity in the Antarctic Deep Sea, the first black smokers in the Southern Ocean, as well as hydrothermal vents and methane seeps in the Arctic, South Georgia, North Atlantic and Red Sea. So far, I have formally described 28 species and am proud that 5 species carry my name.

• What have you enjoyed about BIOPOLE so far? 

“Getting an old dog to learn new skills” – treating tissue samples for lipid analyses and looking for calanoid fatty acids is new to me. I enjoy that BIOPOLE’s marine carbon cycle research includes the carbon holders from the microbes and phytoplankton in surfaces waters via zooplankton and nekton in the water column to the benthic invertebrates on the seafloor.

• Tell us about a skill or trait unique to you that you would like to share? 

Turning scientific drawings and photos of marine animals into sewn soft toys, like the deep-sea barnacle Bathylasma hirsutum or flabellinid nudibranchs, Christmas tree ornaments, and crochet creatures, like the Arctic seep and vent fauna.

Katrin Linse from British Antarctic Survey