Ocean-based carbon storage

Our research seeks to accelerate the ocean-based storage of carbon as a means to securely remove carbon from the atmosphere and lock it away. We are investigating a number of potential technologies, and considering their environmental impact, efficiency, cost and scalability.

What we know

The oceans are by far the largest reservoir of carbon on the planet. Ultimately they will absorb and store 80% of the anthropogenic carbon, however, this process takes thousands of years.  Our research investigates the potential to speed up the ocean’s uptake and/or subsequent storage of atmospheric carbon.

Key research challenges

Our research will investigate several ocean carbon storage strategies that are at varying levels of development.

Enhanced ocean-carbon absorption and storage through nutrient addition:

• What is the carbon capacity and storage timescale of stimulated phytoplankton blooms to export and store carbon?
• Can the ocean carbon remineralisation process be altered to enhance carbon storage?
• Where are the best locations for nutrient addition?
• What are the impacts on ecosystems and upper trophic levels of nutrient addition? Are there other potential benefits?

Enhanced ocean-carbon absorption and storage through alkalinity enhancement:

• The most abundant source of alkalinity is alkaline rocks (limestone, mafic rocks) but their dissolution into the ocean is slow, and therefore requires enhancement. What other products, such as mine tailings or other waste materials might be used as a source of alkalinity?
• What are the potential impacts of these additions for marine life?
• What is the most effective and efficient means to deliver these materials to the ocean?
• Can these systems be designed to be combined with other industries (i.e., hydrogen production) to maximise carbon removal and other benefits?

Enhanced ocean-carbon storage through direct CO₂ injection:

• Where are the best locations to inject carbon to maximise carbon storage?
• What are the potential biological impacts of the injected carbon?

If successful, what might this program achieve?

Identify the best options for utilising the ocean for anthropogenic carbon storage.  In assessing the attractiveness we will assess the ocean’s carbon storage capacity and efficacy, the potential biological impacts and the possible co-benefits of using the ocean for carbon storage.