Adding Mineral Olivine to Oceans Could Reduce Emission Levels by 10%

A study led by the Alfred Wegener Institute for Polar and Marine Research has suggested that adding of mineral dust to the ocean as a means of carbon sequestration could help combat global warming. But the scale of the project would be huge and the whole balance of the ocean might well change.

Speaking of the controversial geoengineering technique, Peter Kohler, the leader of the study, admitted:

It certainly is not a simple solution against the global warming problem.

Whilst such a gambit would help to offset the acidification of the ocean and remove CO2 from the atmosphere, it would require a billion tonnes of mineral olivine, which would itself require a mining operation on an equivalent scale to the global coal industry.

Mineral olivine is present beneath the earth’s surface all over the world and, when dissolved, would increase the oceans capacity to absorb carbon. According to Kohler, three billion tonnes of the mineral dust would be enough to reduce the amount of man made emissions in the atmosphere by 10%. Of course, these carbon savings would be eaten into by the extra emissions caused by obtaining and distributing to olivine.

There would also be implications for sea life, with changes in the balance of plankton species being just one foreseeable consequence. Kohler said:

Silicate is a limiting nutrient for diatoms, a specific class of phytoplankton. The added silicate would shift the species composition within phytoplankton towards diatoms.

Alternative geoengineering tactics include releasing sulphate particles into the air so as to block sunlight. However, such a move could lead to irreversible changes to the atmosphere. Kohler argues:

With atmospheric geoengineering, once you start you have to keep going. If you stop there may be a very abrupt increase in warming on a magnitude you do not know, if carbon emissions have not been reduced.

Mineral olivine on the other hand dissolves with two years, meaning its effects on the make up of the atmosphere are relatively instantaneous and impermanent.

International agreements governing such geoengineering practices have been described as “inadequate” by Kohler and the cause for getting governments to consider how such projects might be undertaken in future has not been helped by the actions of ‘rouge’ geoengineers such as the American businessman, George Russ, who dumped 100 tonnes of iron sulphate into the Pacific causing a huge boom in plankton levels.

Last September the UK government stated:

It is premature to consider geoengineering as a viable option for addressing climate change. [But] research and ongoing dialogue with the public and other key stakeholders, is vital to inform future policy and decision-making. The conduct of research does not imply an intention to deploy geoengineering.

Green Steve’s Reaction

I’m in the anti-geoengineering camp in general because I think we simply do not know the full consequences of any such practice on a huge and complicated system such as the ocean.

I don’t think I’d be very easily swayed from my position either because no research can account for all the variables involved no matter how thorough the experiments have been.

There is just too much risk of a catastrophe – while the ocean may already contain billions of tonnes of dissolved material washed down rivers each year, there is a balance in place now that could easily be disrupted if we choose to add to this.

We must remember that the sea not only absorbs carbon dioxide, it provides a vital food source for billions of people.

Steve (132 Posts)

Chief writer and editor on Green Steve. Blogging since 2011, Steve likes to delve into a wide number of topics.