Not a very good title I fear. I’m referring to Lovelock and Rapley propose cure for global warming wherein James “we’re all doooomed I tell ‘ee” Lovelock and Chris “used-to-be-my-director” Rapley propose a load of floating pipes to haul up nutrient rich water to cause blooms to lock up CO2.
Its rather short on numbers (how many of these things would you need?)
or that wave action via a flap valve will do the pumping required (I presume it must, because they can’t have got that bit wrong, can they?). A diagram might help. Ah, the BBC has one but I’m still not sure. Maybe I need a video :-). Meanwhile Nude Scientist has Andy Watson equivocal and Hoskers cautious.
The BBC note that a company exists that is proposing this, and indeed has actually started trials: atmocean. So its not really clear why L+R are getting the credit for the idea (except they are famous and atmocean unknown, and unknown companies don’t get published by Nature. Seriously, though: if the L+R letter had been an aricle about science, it would have had to be rejected for lack of novelty). Atmocean even have some numbers: “134 million pipes could potentially sequester about one-third of the carbon dioxide produced by human activities each year”. They want to moor them in vast pipe-farms (“When fully deployed, our 3m diameter by 200m deep pumps spaced 2 km apart will be positioned across 80% of the world’s oceans” so these people are ambitious); more numbers from their faq.
Well, the objections are obvious: maintaining these vast arrays is a problem, as is what they might actually do: bizarrely, the atmocean folk say “The problem we would be most concerned about would be acidification. We’re bringing up higher levels of CO2 along with the nutrients, so it all has to be analysed as to the net carbon balance and the net carbon flux.” – in other words, they don’t know whether this would reduce CO2 or not.
Is it financially viable? Who knows: atmoceans business model page is a 404. Still it would be interesting to see a small scale trial.
Hmm… I’ve just realised quite how ambitious these plans are. Earths ocean sfc is about 4*pi*r^2*2/3 ~ 8*36million km^2 ~ 300 million km^2. At a spacing of 2 km, thats about 100 million in total (close enough to their 134 million for now). So they want to cover the whole ocean (*including the sea ice areas*?) and even that will only sequester (on their doubtless optimistic calculations) 1/3 of current emissions? Not to mention that there are large areas of the ocean where this won’t work. So as a planet-saver its not going to work. You’d be better off with the good old “area the size of spain in the sahara covered in photovoltaics”. At least thats in theory possible.
[Update: surprisingly negative reaction by LeQuere: Other scientists welcomed the proposal as thought-provoking but doubted that it would work.Corinne Le Quéré, who led research this year which showed that oceans were losing the capacity to soak up carbon dioxide, was scathing and feared that if pipes were deployed around the world’s oceans they could exacerbate, rather than cure, the warming trend. “This idea is a complete waste of time,” said Dr Le Quéré, a researcher at the University of East Anglia (UEA) and the BAS. “It doesn’t make sense. There is absolutely no evidence that geoengineering options work or even go in the right direction. I’m astonished that they published this. Before any geoengineering is put to work a massive amount of research is needed – research which will take 20 to 30 years.” I can’t see how she can justify that. It may not work, but then again it might. It would need testing -W]