Into the Blue expedition: iC3 researchers return to the Arctic Ocean

What can the Arctic seafloor tell us about a warmer future?

From September until mid-October, five researchers from the iC3 Polar Research Hub are deep into the Arctic Ocean to investigate how the Arctic Ocean and its surrounding cryosphere responded to past periods of global warmth.

Far below the waves of the Arctic Ocean, layers of mud are quietly preserving a record of environmental change. Buried within these sediments are clues about ocean temperatures, sea ice, ice sheets and marine ecosystems from a time when the Arctic was very different from today.

Exploring the Arctic seafloor

The i2B Arctic Ocean Expedition 2026 is searching the Lomonosov Ridge for sediment archives that can reveal how the Arctic environment changed over millions of years. Gravity and piston coring will recover long sequences of sediment from the seafloor, while geophysical observations help the team understand the geological setting and identify promising locations.

Once sediment cores are brought on board, they become natural archives of environmental change.

Reading the Arctic’s past

The team uses a range of approaches to extract and contextualise information from these archives. 

For Henry Patton, marine geophysics provides a way to look beneath the seafloor and reconstruct the processes that shaped the Arctic Ocean and its surrounding ice.

Adele Westgård, a postdoc working on micropalaeontology and geochemical climate proxies, studies tiny marine fossils and their chemical composition. These microscopic organisms can provide valuable information about past ocean conditions.

PhD student Lena Anders uses the same approach and focuses on the last interglacial, about 120,000 years ago. In addition, she studies biomarkers preserved in the sediments to reconstruct sea-surface temperatures and determine whether past Arctic sea ice was seasonal or perennial.

Meanwhile, postdoc Ben Boyes brings expertise in the history and behaviour of the Arctic cryosphere. By combining evidence from sediments, the seafloor and ice-related features, researchers can investigate how ocean and ice systems changed together.

Jochen Knies, who co-leads the Into the Blue (i2B) project, will ensure that all scientific activities contribute to the overall project goal of reconstructing the past of the Arctic Ocean and better understanding its future.

Looking into a warmer Arctic

Why travel into one of the most remote environments on Earth to study ancient mud?

Because the geological record provides something that observations of the modern Arctic cannot: a window into climates that were warmer than today. By studying these past conditions, our researchers aim to understand how the Arctic Ocean, sea ice and ice sheets responded to sustained warming—and what this can tell us about the Arctic of the future.

For the researchers on board, the cruise is an opportunity to uncover evidence of how the Arctic climate system has changed through time.

The answers are not written on the surface of the Arctic Ocean. They are buried beneath it—waiting to be brought back up, one sediment core at a time.

Find out more

The i2B Arctic Ocean Expedition 2026 can be followed here. More info about the i2B project can be found here.

Lena Anders is an iC3 affiliated PhD student working on the Into The Blue (i2B) project, based in the Department of Geosciences at UiT The Arctic University of Norway, Tromsø. To find out more about her work, please check out her publications, or contact her by email.

Adele Westgård is an iC3 affiliated postdoc working on the Into The Blue (i2B) project and the ARCLIM project, based in the Department of Geosciences at UiT. To find out more about her work, check out this blog and her list of publications, or contact her by email.

Ben Boyes is an MSCA postdoc working at the iC3 Polar Research Hub, based in the Department of Geosciences at UiT.  To find out more about his work, please check out his list of publications, or contact him by email.

Jochen Knies is a researcher in the Department of Geosciences at UiT and at The Geological Survey of Norway. He is part of the iC3 Polar Research Hub where he leads a research unit that aims to reliably estimate how carbon cycles and ocean ecosystems altered during past ice sheet retreat. He additionally co-leads the Into the Blue (i2B) project. His research focuses on reconstructing the past of the Arctic Ocean.