Why using the oceans to suck up CO2 might not be as easy as hoped

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The study found that dissolving olivine in artificial seawater produced less of an increase in alkalinity than expected. The results for other minerals were not expected to boost ocean alkalinity.

There are doubts about a different approach to ocean-based approaches: growing seaweed and sinking it to suck up and store carbon.

In the coming decades, finding viable ways to pull down greenhouse gases will be vital. The world may need to remove 10 billion tons of carbon dioxide annually by midcentury in order to limit warming to 2 degrees.

According to the research group Ocean Visions, boosting ocean alkalinity could remove tens of billions of tons each year. The National Academies panel noted that it would require a number of different things, all of which would have a negative impact on the environment.

The final word on whether any of these methods will be feasible ways of helping to reach the carbon removal targets has not been delivered by the new studies.

According to Michael Fuhr, one of the authors of the olivine study, their findings suggest that this approach is not as easy as expected. It could include areas where the waters are low in salinity but rich in organic sediments, which will increase acidity.

Additional lab experiments and fieldwork will be needed to determine how well this method works in the real world, what the ideal conditions are, and whether other materials are more promising.

The olivine process doesn't work the way we thought it would, according to an email from a researcher. One of the most promising and permanent methods nature gives us is the mineral.