There is a protest brewing over the Lohafex experiment, involving ocean fertilisation. RV Polarstern, a German research ship, is to dump twenty tons of iron sulphate over 300 square kilometres of the Scotia Sea, off Chile's coast, near the Antarctic Peninsula.
Here's my letter to one of the scientists involved.
Dear Prof. Smetacek
I have just learned of the Lohafex experiment. As you know, there is brisk opposition to it from some greens, mainly operating on the Moral Hazard principle, and also concerned about possible environmental side effects of the experiment. I am a veteran UK Green Party activist, (and of the Campaign Against Sea Dumping) but I am minded to support experimentation in ocean fertilisation. So I am about to come under fire from my own side.
It is not clear from my reading about Lohafex as to where the iron is to be deposited. An upwelling site is mentioned. It seems to me that the best place to introduce the iron is in optimal proximity to a downwelling site, optimal in the sense that the algal bloom will have maximised its CO2 uptake at the point where it leaves the surface layers. This would not only maxmise the CO2 sink, but would also minimise the anxieties about unwanted side effects.
I would be grateful for your comments on this suggestion.
Note: at downwelling points, the surface currents sink to the bottom of the ocean. There the algae can be precipitated out into the sediment, thus taking carbon out of circulation. One atom of iron is supposed to be able to fix 10,000 atome of carbon, which sounds like a good deal to me. Further study of the maps suggests that the bloom from the Lohafex experiment may be conducted to a downwelling site.
Clearly, we have to be careful with geo-engineering, but I think it is wrong to oppose experimentation absolutely.
I believe we can avoid catastrophic global warming, but only if we go for a zero-carbon economy AND enhance Gaia's carbon sinks, which are showing signs of failing.