Ninis Rosqvist is a professor of geography, with a focus on physical geography, at Stockholm University. She has 40 years of experience researching cold environments, including Greenland and Antarctica, as well as the Kebnekaise and Abisko Mountains. During iQ2300 2025/26, she is leading research on a project investigating glacier surface mass balance.

Can you briefly describe what your research project, Surface Mass Balance (WP8), is about and what research questions you want to answer?

– We collect data that show how much precipitation falls over time and how it is distributed within the geographical area we study. We need to understand how different processes in the atmosphere affect both the amount and distribution of precipitation. Such information is needed, among other things, to improve mathematical models that describe the impact of climate.

– A glacier's mass balance is determined by how much snow is added and how much snow – and possibly ice – melts during a year. In the area we are investigating, there are short periods with temperatures above 0 degrees when air from the surrounding ocean penetrates over the continent, but snowmelt is still uncommon.

Why is the Riiser-Larsen Ice Shelf particularly interesting for studies of snow accumulation?

– The entire Riiser-Larsen Ice Shelf drainage area is interesting for studies of how much snow falls and how it is distributed. We have chosen to measure this along a line (a transect) from the edge of the ice shelf, where it meets the sea, up to the polar plateau, i.e. above the Svea research station. This gives us a picture of how snow accumulation varies with distance from the coast and with height above sea level.

– In the late 1980s, firn cores (firn is year-old snow) were analyzed. These cores were 10 metres long and represented the period from 1972 onwards. We will revisit these sites to build an even longer data series.

How is data collection done in practice – what methods and instruments do you use during the fieldwork?

– We take the top samples by hand in a pit, perhaps a few decimetres deep, since that snow is likely to be quite loose. We then drill out cores of hard snow and firn (90 mm in diameter) and analyze them using the laboratory equipment we take with us into the field, a so-called LISA box. By melting the core and analyzing the chemical content of the meltwater, we can identify annual layers and calculate how much snow has been added between seasons. We also measure the density of the snow to calculate how much water the snow and firn contain.

– We expect to be able to go back about 10 years at many sampling sites. We will also saw a firn core into 5 cm pieces and bring them home (in melted form) to analyze other chemistry in the lab. In some places, we will drill further back in time to connect to the existing data series. This may allow us to present a sequence of about 50 years.

– Using ground-penetrating radar pulled by snowmobiles, we measure through the snow and firn to track the same layers we identify through the chemical analysis. By measuring between and around the sampling sites, we also gain knowledge about how the snow is distributed geographically.

What can the analyses of the drill cores (density and chemistry) tell us about the climate over the past 50–100 years?

– Above all, the data show how much snow has been added in different places, and whether there has been melting. We can detect melting if we find ice layers in the snow – i.e. traces of meltwater that has refrozen.

How is this data used to improve climate models or satellite-based observations?

– We use a climate model with high spatial resolution. With the right input data, it can calculate how much snow falls in different places. Using our field data, we can test how well the model performs and improve it. Satellite information, such as radar data, can be used to measure how the height of the ice surface changes over time. The density of the snow affects the interpretation of radar signals, so that information is important.

What challenges are there in sampling and logistics along the transect in the East Antarctic inland environment?

– Safety is paramount. We will mainly travel along a route that is entered into our GPS and is considered to be relatively safe. There are no known glacial crevasses along it, and several previous expeditions have travelled this way. Since the analyses in the field take a long time, it will be a challenge to keep all parts of the LISA box operational – and to keep ourselves warm at the same time.

How do you collaborate within the team and with other work packages in iQ2300 – before, during and after the field season?

– In our team (WP8), we are three researchers: myself and two colleagues from the Danish Meteorological Institute: Ruth Mottram – who has done fieldwork in Greenland several times – and Clément Cherblanc, a PhD student. We first met during the training in Abisko. We then prepared by getting to know the equipment before the expedition. We will analyze the data together already in the field, continue after the field season, and then write several scientific articles – also together with other researchers in iQ2300. The project is divided into different work packages, but the fundamental questions are shared, so collaboration across work package boundaries is very important.

How are the results from WP8 connected to the larger question of sea level changes in iQ2300?

– Knowledge of how changes in atmospheric circulation affect the ice sheet is important, as it forms the basis for simulations of how future warming may affect Antarctica. The area we are studying is an important geographical piece of the puzzle in a larger context – where the key question is how the balance between snow accumulation and melting in the East Antarctic Ice Sheet may affect future sea level changes.

What do you personally hope that the work package will contribute scientifically?

– I hope that we get really good results showing how snow accumulation has varied over time, and that we can use that knowledge to improve the climate model so that projections of future warming impacts become more reliable. I think it is exciting to work with a long record, maybe 50 years, but then we have to manage to drill cores at least 25 metres long. That will be a challenge and will take a long time to analyze.

Is there anything you are particularly looking forward to about this year's expedition?

– I am looking forward to finally visiting Wasa. I have not been there before, but have chosen to do research on an island outside Antarctica where smaller glaciers are melting quickly. In the mountains, I have spent many years digging and drilling in wet snow on various ice sheets, so I am also looking forward to working with dry snow – which hopefully has not started to melt yet.

– Some of us participating in this year’s expedition have worked together before in the Swedish Arctic, so it will be fun to get started again together. And of course: celebrating Midsummer at the same time as Christmas is a fun contrast!

Researchers participating in work package 8

• Ninis Rosqvist, Stockholm University (PI)
• Ruth Mottram, Danish Meteorological Institute (Co-PI)
• Clément Cherblanc, Danish Meteorological Institute (PhD student)