It might not be too difficult to apply. Australia has iron deposits and the infrastructure to transport it. Then it's loaded into an old ship or barge which sails to a suitable spot in the Southern ocean and blown into the air with a fan or other device and the strong prevailing winds act to distribute it over a wide area of ocean. I have heard cost estimates that vary greatly so I'm not sure just how economical it is, but it sounds promising. As for number of boats required, well if it turns out to be a cheap we'll soon round up enough. Old clunkers will do. It's not as if we need anything fancy for this job. boats. There is plenty of room in the Southern ocean for seeding and capturing carbon. The exact effects it has on ecosystems will have to be carefully measured and may limit how much carbon can be sequested. If it turns out to be good for fish stocks that will be a plus.

There hasn't been a lot of talk about this in Australia. I'm mildly surprised that coal and power companies haven't pushed this as part of their, "By talking about solutions we are making it look as though we are actually doing something," strategy. But I guess solutions involving complex machinery and pumping stuff underground comes more naturally to them as that's what they deal with everyday.