They propose that vertical pipes some 10 metres across be placed in the ocean, such that wave motion would pump up cool water from 100-200 metres depth to the surface, moving nutrient-rich waters in the depths to mix with the relatively barren warm waters at the ocean surface.Interesting.
This would fertilise algae in the surface waters and encourage them to bloom, absorbing carbon dioxide greenhouse gas while also releasing a chemical called dimethyl sulphide that is know to seed sunlight reflecting clouds.
"Such an approach may fail, perhaps on engineering or economic grounds", they say, adding that the effects on the acidity of the ocean also have to be factored in.
None the less, "the removal of 500 gigatons (500 billon tons) of carbon dioxide from the air by human endeavour is beyond our current technological capability. "If we can't 'heal the planet' directly, we may be able to help the planet heal itself."
One version of the scheme sees around 10,000 pipes in the Gulf of Mexico, they told The Daily Telegraph.
"In the Gulf this alone may be important for reducing the severity of hurricanes. It is local self interest such as hurricane prevention and the restoration of fisheries that may pay for the project."
I say, lets build a couple of these pipes and see what happens. I think this could be a good idea not just to reduce the level of CO2, but also to increase the amount of sea life (and fish that we can eat) and decrease the severity of hurricanes.