Analysing marine geoengineering technologies

Most geoengineering schemes will affect the oceans, but this paper is restricted to a critical assessment of four technologies. Two methods are albedo-increasing: Solar radiation management by seeding marine clouds with condensation nuclei in order to make them more reflective, i.e. whiter. Micro bubbles/seafoam that make parts of the sea more reflective, or whiter. Two methods aim to change ocean biogeochemistry, so as to increase photosynthesis: Using the oceans as carbon sinks through trace element fertilisation, especially iron. The idea is to produce “algal blooms” to increase photosynthesis, after which the photosynthesising organisms sink to the ocean floor and store the carbon there. Ocean upwelling of nutrient-rich water.