Fingerprinting bioactive trace elements in a changing Arctic Ocean

The Arctic Ocean is undergoing dramatic environmental change and has warmed twice as fast as the rest of the planet. The reduction in sea-ice has increased primary production [1] however, predicted future changes in primary production remain uncertain as the source of bioactive trace elements such as iron, zinc and cobalt essential for phytoplankton growth are hotly debated. Sea-ice melt is predicted to limit primary production while enhanced trace metal inputs can be observed from shelf seas [2]. Critically, our ability to constrain current trace metal supply from meltwater and shelf seas requires a better understanding of the cycling between dissolved and particulate phases, and the time scales governing these processes.
The aim of this study is to fingerprint the sources and quantify the fluxes of bioactive trace metals in the Eastern Arctic Ocean. This will involve collecting seawater samples and observational data across environmental gradients (temperature, nutrients, metals) and combing this with novel radium isotope methods. This work will provide essential rates of supply of bioactive trace elements from shelf waters and ice melt to underpin our understanding of trace metal supply to primary productivity and hence the carbon cycle in the Arctic Ocean under future ice-free conditions.