A multi-tracer investigation of ocean circulation and ventilation in the Canada Basin
ETH Zurich
Lay summary
The project “A multi-tracer investigation of ocean circulation and ventilation in the Canada Basin” aims to create a synoptic view of all water flows into and out of the Canada basin, evaluating the inputs of Atlantic water but also Pacific water flowing through the Bering Strait. This is critical given the accelerated warming of the Arctic due to climate change, partly driven by increased flows of warm, Atlantic derived, waters carrying heat into the Arctic ocean interior. Two isotopes in particular, 129I and 236U, have recently proven to be excellent tracers of ocean currents and mixing regimes, regularly released into the Atlantic Ocean by nuclear reprocessing facilities in Europe. Given their known release dates and volumes from a point-like source, the full potential of these tracers is currently being explored in the Arctic as a method to quantify water-mass transport and mixing in the region. The position at which Atlantic and Pacific waters meet can be identified by the respective presence / absence of 129I and 236U, and shifts year-on-year in response to the state of the atmospheric circulation regime known as the Arctic Oscillation Index. This also controls the direction of circulation in the Beaufort Gyre and position of the Arctic Ocean Boundary Current which is composed of Atlantic sourced water. We will then combine these state-of-the-art tracers with additional input and process tracers, including 14C and 39Ar for ventilation of the deep ocean, while Nd and Hf will evaluate sources of freshwater input to the surface ocean.
Details
| Regional focus | Arctic |
| Location | The Beaufort Gyre / Canada Basin |
| Funded amount | 7,690 CHF |
| Project dates | 5th July 2022 – 15th July 2023 |
| Category | Polar Access Fund |