Interview: "Ice shelves in Antarctica play a key role in bringing nutrients from the deep ocean to the surface"

In this interview, PhD student Koen van der Heijden explains his research on ice-ocean interactions at the Fimbul Ice Shelf, the challenges of working with observational data, and his passion for climbing and outdoor activities.

Can you briefly describe yourself and the focus of your research?

My name is Koen, I’m an iC3-affiliated PhD student in physical oceanography at the University of Bergen.

My research focuses on ice-ocean interactions, specifically the formation of ice shelf water and frazil ice at the Fimbul Ice Shelf in Antarctica. This process involves meltwater from the ice shelf influencing the surrounding ocean, which has broader implications for nutrient transport and biological activity.

Credit: Koen van der Heijden

Why is it important to study these processes?

Although it’s a local process, it has significant regional and global relevance. Meltwater and frazil fluxes from ice shelves play a key role in bringing nutrients from the deep ocean to the surface, which supports biological productivity.

While I focus on the physical aspects, this nutrient transport is crucial for the ecosystem and links physics to biology.

Does this process occur elsewhere?

In my PhD, I’m focusing on the Fimbul Ice Shelf in Queen Maud Land, Antarctica. However, similar processes occur at many ice shelves across the continent.

Ice shelves are melted from below by the ocean, and the resulting meltwater, being less dense, usually rises toward the surface, where the ice crystals I study can form.  So although I focus on one particular area, the underlying dynamics are widespread.

How are you conducting this research?

I’m currently working with observational data collected during annual resupply cruises to Antarctic research stations. These cruises gather CTD profiles—measurements of temperature, salinity, and other variables. I analyze these profiles to identify signals of meltwater and find signs of strong mixing.

There’s also a modeling component to my PhD, which focuses on process-based simulations rather than large-scale circulation models. I am also hoping to join the Norwegian Southern Ocean cruise next year to collect additional observations.

What challenges have you faced in your research so far?

One major challenge has been transitioning from modeling to working with observational data. Observational data can be a bit messy and incomplete. Unlike model data, which provides clean, structured outputs, observational data can have gaps or calibration issues.

Adapting to this has been a learning curve, but it’s also rewarding to work with real-world measurements.

What technologies or methodologies excite you in your field?

One exciting development is the potential use of a towed instrument called a TRIAXUS, which can collect continuous 2D profiles by moving up and down through the water column.

Additionally, autonomous underwater vehicles are now being used to explore beneath ice shelves, providing unprecedented data from these hard to reach areas. Both technologies represent exciting advancements in Antarctic research.

What do you enjoy doing outside of science?

I love climbing, hiking, and being outdoors. I’ve recently started climbing again, which has been really fun. I also enjoy running and swimming. On quieter days, I like cooking, especially on weekends when I have more time to experiment, and making and listening to music.

What does an ideal day off look like for you?

I like to start the day slowly, with some coffee and reading. Then I’d do something active, like going out into nature or  meeting up with friends. In the evening, I’d spend time with friends, maybe have food or a drink together.

Can you share a book or movie that has influenced you?

A book that really impacted me is The Eighth Life by Nino Haratischwili. It’s a beautiful story about Georgia’s history told through the perspective of a family over several generations. It inspired me to visit Georgia and left a lasting impression.

What are you looking forward to in the next year?

Professionally, I hope to publish my first paper and continue making progress on my PhD. Personally, I’m working on improving my Norwegian and hope to reach a level where I can function comfortably in the language.

Koen van Der Heijden is an iC3-affiliated PhD student at the University of Bergen, Norway. To find out more about his work, check out his list of publications or contact him by email or LinkedIn.