We’re not on track to avoid global warming beyond 2°C with just emissions reduction. The IPCC has made it clear that, in addition to cutting emissions, we need to remove billions of tonnes of CO2 from the atmosphere. The big question is: how do we do that?

The oceans offer several methods for marine carbon dioxide removal (mCDR) that could help. One of these methods is ocean alkalinity enhancement (OAE). The idea is to add alkaline substances to seawater to boost its ability to absorb CO2. There’s some data suggesting OAE could work, but also some pointing to substantial complications.

Several enterprises are already diving into OAE for carbon dioxide removal. But independent research is essential to figure out if what these enterprises propose could actually work. This research needs to be unbiased and thorough, starting with lab experiments, numerical models, and studying natural processes that resemble OAE.

Field studies are another crucial step. These studies test OAE under real-world conditions and provide the most direct evidence of whether it could work. In autumn 2024, we kicked off a small-scale field study in Southern Tasmania to see if OAE could remove atmospheric CO2 and what effects it might have on marine life in seafloor sediments. Importantly, our research is purely academic, independent of commercial OAE ambitions. Our goal is to provide robust, independent evidence on whether OAE could sustainably contribute to the unavoidable need for carbon dioxide removal, or whether it cannot live up the high hopes some put on it.

We aim for full transparency. The presentation linked below details the motivation for, and the goals of our Ocean Alkalinity Enhancement field experiment in Tasmania.

Lennart Bach