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What is the largest amount of iron that will be used to fertilise an ocean as part of a single geoengineering effort, by the end of 2026?
Iron fertilisation is the introduction of iron to iron-poor areas of the ocean surface to stimulate phytoplankton production to thereby draw carbon out of the atmosphere and into the ocean. Phytoplankton converts some of the CO2 dissolved in the ocean into biomass, which is then transported into deep sea by ocean circulation and gravity; effectively resulting in the long-term sequestering of carbon (Yoon et al., 2018).
Researchers worldwide have conducted 13 major iron-fertilization experiments in the open ocean since 1990 (Tollefson, 2017). All have sought to test whether stimulating phytoplankton growth can increase the amount of carbon dioxide that the organisms pull out of the atmosphere and deposit in the deep ocean when they die. Determining how much carbon is sequestered during such experiments has proved difficult, however, and scientists have raised concerns about potential adverse effects, such as toxic algal blooms.
What is the largest amount of iron, in tonnes, that will be used to fertilise an ocean as part of a single geoengineering effort, by the end of 2026?
This question resolves as the largest amount of iron, in tonnes, that will be used to fertilise an ocean as part of a single geoengineering effort (with the intention to intervene in the Earth's climate system), by the end of 2026.
A single geoengineering effort is a project in which the relevant actors act on behalf of a various organisations (e.g. national government or research organisation) that coordinate in precise terms on the employed geoengineering methods as well as the the extent to, and the duration for which these are to be deployed.
In case the fertiliser is a compound of iron, such as iron sulfate, the question resolves as the elemental weight of iron, which is to be converted using the relevant formula that specifies how many moles of iron the total weight of the fertiliser contains, which is then converted to the weight of elemental iron using the formula or a converter. In the case the fertiliser is a mixture of different iron-containing compounds, the weight of iron shall be determined by the same method for the individual compounds multiplied by the fraction of its weight to total weight.
This question resolves ambiguously no such relevant geoengineering effort occurs before the end of 2026.
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