Now this is a piece of research into climate change that I can really get behind. It's one of those win/win policies that environmentalists like to tell us are out there. It might even be "no cost" for the value of the fisheries created might be more than the cost of doing the work, the climate change effect coming for free.

OK, OK, reality time, this is very much early stage work and no, we don't know how effective it is going to be.

As a result of the findings, a ground-breaking experiment will be held this month off the British island of South Georgia, 800 miles south east of the Falklands. It will see if the phenomenon could be harnessed to contain rising  carbon emissions. Researchers will use several tons of iron sulphate to create an artificial bloom of algae. The patch will be so large it  will be visible from space. Scientists already knew that releasing iron into the sea stimulates the growth of algae. But environmentalists had warned that to do so artificially might damage the planet’s fragile ecosystem.

We know very well that the basic idea works. Large areas (up to 70% of the global ocean) of the sea are nutrient poor, specifically iron poor. We can see what results when there's a storm in the Sahara for example, and iron rich dust gets blown over the Atlantic: algal blooms. Some such algae, when they die, fall to the ocean floor and lock up the carbon they contain. Others become the beginning of a food chain that results in lots more yummy tuna for us to eat. So, if we deliberately throw iron into the ocean can we create such blooms, such richer fisheries and such carbon sequestration? 

As I say, we know that this basic idea does in fact work, we just don't know how well. We do know that there won't be any appalling side effects, for we actually did this once before: all that soot and slag from all those coal fired ships for a century or so did not lead to catastrophe after all (and yes, they did create areas of higher nutrients and thus more algal growth). But what we want to find out is how much of that carbon captured from the atmosphere goes to the bottom of the ocean and how much goes right back, either from the algae themselves or the fish (and us! Yum!) that feed upon them? A commercial company called Planktos that wanted to conduct this very experiemnt a could of years back thought that 20% was sequestrated for the long term.

20%? On a blog a long time ago and far away I ran through these numbers. Given the cost of iron powder (or as here, iron sulphate) the cost of sequestrating one tonne of carbon would be around 3.3 US cents. Yes, that really is 0.033 of a dollar. To sequestrate all of the 5 billion tonnes of current anthropogenic emissions would thus cost under $2 billion dolllars. Erm, in raw material costs.

Yes, of course, these numbers are wrong. Entirely wrong, very much back of a fag packet wrong. Let's say they're an order of magnitude out. Still costs less than $20 billion annually. Two orders out: still less than $200 billion. Even that, as an annual cost, pales into insignificance against the cost of, say, the Stern Review's prescriptions.

OK, let's imagine that this is indeed wrong. That there's some error (in my calculations, in the basic idea itself perhaps). That still leaves us with a very large question. Why is only one experiment being done upon this? We're being asked to spend trillions upon trillions of dollars over the next few years to "beat climate change" so why isn't everyone and their granny investigating such possibly low cost methods of doing so?

Thre's a cynical little voice in me that says that it's because there's an awful lot of people who aren't as interested in solving climate change as they are in using it as an excuse to impose their vision of the good life upon us.