Hal Plotkin has written an informative piece for SF Gate about a controversial new technique for seeding plankton growth in our oceans.

See:
Ocean Rescue Planktos Foundation hopes to reduce global warming by fertilizing the seas.

A group of scientists say it may be possible to simultaneously reduce global warming and increase dwindling supplies of fish around the world by adding relatively tiny amounts of powdered iron to the ocean.

Although the concept is controversial, several demonstration experiments have already been conducted, including by the Half Moon Bay-based Planktos Foundation, which hopes to eventually turn the cultivation of plankton forests at sea into an environmental-restoration business similar to reforestation on land.

The proposal has sparked considerable debate within the scientific and environmental communities, in part, because some energy and oil companies see it as a possible way to offset atmospheric pollution caused by their products. If it works, its backers say, the idea could help save humanity from the twin dangers of dying oceans and an overheated planet. On the other hand, others see it as an unworkable scheme that would interfere with nature, one that could lead to consequences even more dire than those it seeks to address.