Past Arctic climate secrets to be revealed during i2B Arctic Ocean Expedition 2025

What’s Happening

From 16^th August to 19^th September 2025, the Norwegian research vessel R/V Kronprins Haakon will be sailing into the Arctic Ocean for an expedition organised and funded through the prestigious European Research Council Synergy Grant “i2B – Into The Blue”. The i2B Arctic Ocean Expedition team consisting of 25 scientists will collect new geological archives that will shed light on Arctic climate during past ‘warmer-than-present-day’ conditions (interglacial periods). These archives are crucial to understand the impact of a “blue” (free of seasonal sea-ice) Arctic Ocean during key interglacial periods, ca. 130,000 and 400,000 years ago. Follow the i2B Arctic Ocean Expedition: https://arcg.is/0favaf0

What are the global impacts of an ice-free Arctic? How will the Arctic develop with increasing climate warming? What does an ice-free Arctic mean for our environment and our society? These are the key questions that the i2B project will address over the coming years, using cutting-edge research, geological records, and numerical models. i2B brings together researchers from UiT The Arctic University of Norway, AWI - The Alfred Wegener Institute – Helmholtz Centre for Polar and Marine Research in Bremerhaven (Germany), NORCE Climate and Environment in Bergen (Norway), and UiB University of Bergen (Norway).

Why It Matters

• The impact of global warming on the Arctic has long preoccupied researchers, because the concrete impacts on the region and our entire planet have so far been unclear.
• Summer ice melt starts earlier and lasts longer each year, with future projections showing sea-ice-free summers before 2050.
• These trends raise broader climate challenges in the Arctic such as marine heatwaves, Atlantification of the Arctic Ocean, ecosystem shifts, altered weather patterns, ice-albedo feedbacks, methane release, and this on top of new geopolitical dynamics in an ice-free Arctic.

What Our Expedition Will Do

• Collect high-resolution sediment cores at multiple sites to reconstruct temperature, sea ice conditions, oceanography and the ecosystem during warm past interglacial periods, ca. 130,000 and 400,000 years ago
• Compare these data with modern observations to test how the Arctic transitioned to a “blue ocean” state in warmer climates.
• Examine whether the past serves as a window into our future – are we at the brink of a new tipping point?

Expedition Team

• Expedition leaders/chief scientists:
  Jochen Knies (jochen.knies@uit.no) and Stijn De Schepper (stijn.deschepper@uib.no)
• 25 scientists from nine different countries

Links & Further Reading

• Into the Blue: An ERC Synergy Grant Resolving Past Arctic Greenhouse Climate States (Published in Challenges): https://doi.org/10.3390/challe16030036
• The changing nature of future Arctic marine heatwaves and its potential impacts on the ecosystem (Published in Nature Climate Change): https://doi.org/10.1038/s41558-024-02224-7
• Seasonal sea ice characterized the glacial Arctic-Atlantic gateway over the past 750,000 years (Science Advances):  https://doi.org/10.1126/sciadv.adu7681
  
  - Press release: Frozen, but not sealed: Arctic Ocean remained open to life during ice ages: https://www.eurekalert.org/news-releases/1089766