The amount of iron in the ocean, 
it's vanishingly small.
If you think about an Olympic sized swimming pool,
the amount of iron in the open ocean is literally
represented by just a drop of water in
that swimming pool.
I'm Kathy Barbeau and I'm a marine chemist and
a professor at the Scripps Institution of Oceanography.
I study the biogeochemical cycling of
trace elements in the marine environment
So primarily iron which could be an
important micronutrient for
phytoplankton in the open ocean.
Those few atoms of iron play a crucial role
in important enzymatic reactions—
photosynthesis, respiration,
and in the larger overall global cycling of carbon and nitrogen.
I work in both the field and in the laboratory.
In my research in the field as a trace metal chemist,
the big challenge for me is to try 
and get clean samples.
To go out on this large metal object 
and sample the surrounding seawater
where metals are present at 
vanishingly low concentrations
and not contaminate your samples.
So I have a rosette with special bottles
and special cables that I use.
When I go to sea, I also 
bring a clean laboratory with me
that we set up with a positive pressure,
everything non-metallic materials,
and that's where we process our samples.
I work on the interface between 
chemistry and biology
so I also use genomic tools
to look at how trace elements 
like iron cycle in seawater.
So that we understand what's happening now,
what's happened in the past,
and what's going to happen going forward.
