This cruise is a long time coming—the original proposal submitted by Chief Scientist Prof. Dr. Eric Achterberg estimated it would happen in 2017 or 2018! After we finally loaded the ship with equipment and 40 motivated scientists in late October 2024, we had to wait a few more days in port for repairs and inspections. Consequently, everyone was excited when we finally left Durban harbor on 2^nd November, and many of the scientists gathered to watch the city lights disappear from the monkey deck.

And why are we scientists gathered here to cross the Southern Indian Ocean from Durban, South Africa to Fremantle, Australia? The main aim is to study the aptly named trace elements, chemical elements found only in trace amounts in the ocean. While their concentrations are small, their impacts are important and wide-reaching. Trace nutrients (aka micronutrients) such as iron and manganese are as vital for life in the ocean as they are for life on land. Other trace elements such as radium and thorium can be employed as proxies to help us understand and quantify ocean processes. We are interested in how these trace elements are introduced into the ocean and how they are distributed once they get there.

The chemistry team will measure the concentrations of trace elements in dissolved and particulate forms. Chemists will also monitor macronutrients, oxygen levels, and carbonate chemistry (a delicate balancing act of chemical reactions that determines seawater pH).

To better understand the distributions of trace elements (among other things), we need to understand the movement of currents over various spatial and time scales. Physicists seek to accomplish this using a variety of instruments, including floats that are released to travel along with the currents. 

Physics and chemistry drive the biology of the oceans, and we have several biology teams onboard to delve into the living side of things. Biologists will use genomic methods to conduct surveys of the biotic community, from the microscopic phytoplankton at the base of the food web to the charismatic siphonophores and cephalopods.

We have a busy program with a full science team studying processes spanning great distances and time scales! Stay tuned as we check in with the working groups for a more detailed look into how their research is progressing.