Antarctic Canyon Experiment (ACE)

Funded by: European Research Council

Funding amount: £2.4 million

Date: 2025–2030

Principal Investigator: Dr Jenny Gales , Associate Professor in Hydrography and Ocean Exploration

Partners: University of Gothenburg (Sweden), Northern Illinois University (USA), the National Institute of Water and Atmospheric Research (New Zealand), National Institute of Oceanography and Applied Geophysics (Italy), The Australian National University (Australia) and the Alfred Wegener Institute (Germany).

The role of organic carbon

The Earth’s climate is controlled by atmospheric CO₂ – an inorganic carbon that plays a crucial role in the carbon cycle and climate regulation. Organic carbon (compounds that contain carbon-hydrogen bonds) is primarily found in living organisms like plants, animals and microorganisms and is essential for life, forming the basis of biomolecules and providing energy for cellular processes.

So, understanding the processes influencing organic carbon transfer and burial between the planet's major stores is crucial to predict and mitigate against future climate change.

Underwater avalanches

Turbidity currents are like underwater avalanches. They are rapid, destructive, sediment-rich bodies of water that flow down-slope and destroy the seafloor infrastructure, transporting and storing organic carbon which affects ecosystems. The largest sediment transfer process on Earth, a single turbidity current is able to transport more sediment to the deep ocean than all of the world's rivers combined.

Organic carbon transfer and storage affects the climate over long timescales – more than 1,000 years. As climatic changes are observed across the planet, it is crucial to reassess global carbon cycle models. However, turbidity currents are largely excluded from these models and no turbidity currents have been measured in glacial or high latitudes.

Antarctica disproportionately affects climate regulation, storing 40% of all anthropogenic (human-made) carbon in the ocean. Projected climatic changes are likely to affect the future storage of this carbon.

The Antarctic Canyon Experiment (ACE) aims to directly measure Antarctica's turbidity currents and organic carbon for the first time.

Informing climate mitigation policies

ACE aims to revolutionise the understanding of the role ice sheets and turbidity currents play in organic carbon cycling. Researchers will assess past, present and future impacts of climate on Antarctic turbidity currents and the transfer of organic carbon to the deep ocean. The project will:

establish the causes, internal character and behaviour of Antarctic turbidity currents through groundbreaking direct measurement and analysis of datasets

determine how turbidity currents and organic carbon changes under past climates and ice sheet dynamics using palaeoclimate, sedimentary and geochemical data as well as new, contemporary measurements – to establish the role of Antarctic turbidity currents in organic carbon transfer to the deep ocean

use these insights to derive parameters of organic carbon flux caused by turbidity currents for global carbon models, predicting how they will change under climatic changes.

Together, this project's outcomes will inform climate mitigation policies.

Dense shelf water cascading (DSWC)

The project involves subsea acoustic and optical instruments, with seafloor sampling and high-resolution seafloor mapping using autonomous underwater vehicles to develop an understanding of the causes, character and behaviours of turbidity currents – confirming triggers as slope failure.

One potential cause of turbidity currents is dense shelf water cascading, which transfers surface waters and organic carbon to the deep ocean. In Antarctic waters, this process removes atmospheric CO₂ over centuries and millennia that slows global warming.

It is known that DSWC can also trigger turbidity currents at mid-latitudes, but the ACE project will directly test whether Antarctic DSWC can trigger turbidity currents.