Wednesday, February 04, 2009

Study Shows Mixed Results of CO2-Absorbing Plankton, Germany Moves Ahead with Testing

There's a controversial idea out there to combat climate change by dumping iron into the oceans to grow plankton, which in turn can absorb carbon dioxide (CO2) from the atmosphere. When plankton die, they sink to the bottom of the ocean, locking away some of the carbon they have absorbed.

A recent study in the journal Nature reports that a big, naturally occurring bloom in the Southern Ocean has helped "lock" away CO2 in sea sediments. However, the CO2 locked away was far, far less than scientists anticipated - 15-50 times short of some expectations.

Nevertheless, some scientists want to take this CO2-absorbing concept one step further and attempt to create a human-made bloom by adding iron to the ocean water to see how much CO2 could be absorbed.


So the question becomes, could we remove significant amounts of CO2 from the atmosphere by "fertilizing" the ocean with iron? And does this hurt the ocean? Scientists still aren't sure exactly how much carbon can be locked away in plankton, and many people are skeptical and opposed to dumping large amounts of iron into the ocean to test what happens.

Germany had suspended an ocean fertilization experiment in the Scotia Sea near Argentina after environmental groups protested that it violated the terms of the UN Convention on Biological Diversity and threatened to damage ecosystems. But a few days after the release of the Nature study last week, the Germans reauthorized this experiment and researchers are moving forward with plans to seed about six tons of iron sulfate over 300 square kilometers of the Sea.

Dumping tons of iron into the ocean sounds scary, but I'm also of the mindset that we need to try lots of different things to combat climate change. But I could be swayed. If there's someone out there who knows more about this technology and research, drop a comment.

via BBC News
and Science Daily

2 comments:

William Carr said...

I think this idea may work, but doing it in the open ocean is chancy.

Rather than risk unforseen effects on the ocean ecology, test the idea in large pools near the ocean.

Use wave or wind power to pump the seawater up to the pools, fertilize the plankton with iron oxide and then collect the samples after a year.

If you were to roof over the plankton pools, you could catch the fresh water as it evaporates and make the pools a useful resource for farming.


And if the process actually works, you could regularly scrape up the dead plankton, squeeze it into pellets, burn it and bury the biochar...

This would allow permanent carbon sequestration on the scale of centuries.

Maria Surma Manka said...

Thanks for the ideas William...I wonder if anyone is working on this?