56. Heidelberger Physik Graduiertentage

UNRAVELLING THE SECRETS OF THE OCEANS USING ISOTOPIC TRACERS

Anne-Marie Wefing

How long does it take for waters to complete a loop through the Arctic Ocean? The Arctic Ocean plays a key role for the global ocean circulation, but answering such seemingly simple questions demands extensive and interdisciplinary research.

The Ocean is a dynamic and complex system, where physical processes such as advection, diffusion, and mixing govern the transport of heat, salt, nutrients, and pollutants across vast distances. Understanding these processes is essential for climate modelling, marine ecology, and investigating global biogeochemical cycles. Isotopic tracers, both stable and radioactive, of natural or anthropogenic origin, serve as powerful tools to quantify these dynamics, offering unique insights into water mass origins, circulation times, and mixing processes.

In this lecture, we will combine physical approaches ranging from fluid dynamics to mass spectrometric measurements to understand different aspects of the marine environment. We will examine how isotopic tracers, when integrated into the framework of physical oceanography, can help constrain the rates and pathways of oceanic transport, estimate ventilation times of the deep ocean, and track the dispersion of anthropogenic carbon.
Following a general introduction to physical oceanography and an overview of tracer applications in oceanography, we will delve into case studies from current oceanographic research based on tracer data from several expeditions to the Arctic Ocean.