MESSING around with ecosystems is an unpredictable business. That proved true again this week when a group of Indian and German researchers gave their first report from the biggest ever experiment in geo-engineering: an expedition to pour iron into the Southern Ocean, a vast area that encircles Antarctica, to stimulate a giant bloom of phytoplankton.
Phytoplankton are tiny algae that absorb carbon dioxide when they
grow and then lock up some of the greenhouse gas when they die and sink
to the seabed. Stimulate the growth of more phytoplankton, the theory
goes, and you might send more CO2 to the bottom of the ocean, where it
cannot contribute to global warming. But the experiment did not quite
turn out like that.
The voyage, a joint venture by India’s National Institute of
Oceanography and the Alfred Wegener Institute for Polar and Marine
Research in Germany, was controversial from the start. Some
environmental groups claimed it was akin to pollution, and thus
illegal. At one point, therefore, the German government ordered the
Wegener Institute to suspend operations while it looked into the
matter. Eventually, permission to continue was given and the research
ship Polarstern made a two-and-half-month passage through stormy seas following the bloom that the researchers had created.