The productivity of the southern oceans is typically limited by the lack of iron -- hence if an iceberg breaks off the Antarctic shelf and carries iron to the ocean, algal blooms are observed.
In an effort to understand these processes and to figure out whether and how they might help to slow down climate change, researchers from Germany and India using the research vessel Polarstern have started a comprehensive experiment (LOHAFEX), fertilising a well-defined eddy of the south atlantic with iron, and monitoring the effects in much more detail than ever before.
Still, the experiment has triggered intense debate in Germany. Amusingly, the chancellor and the research ministry support the experiment, while the environment minister is opposing it quite fiercely. Read my story in
Current Biology vol. 19, issue 4, pp R143-44
There is also a blog (in German) reporting directly from the ship: Polarstern unterwegs.