From its current capacity as a carbon sink to its potential as a site for generating renewable energy, and managing solar radiation, the ocean is increasingly at the forefront of discussions around climate mitigation strategies. However, efforts to develop ocean-based climate interventions expose the ocean to various threats that harm biodiversity, pollute, and change its very chemistry. These negative impacts raise crucial questions about how we balance fighting climate change and the health of the ocean.

Neil Craik

> Professor, Faculty of Environment
> Member of the Waterloo Climate Institute
> Waterloo Climate Interventions Strategies Lab member

Dr. Neil Craik, law professor in the School of Environment, Enterprise and Development and Waterloo Climate Interventions Strategies Lab member, is part of a growing area of research critically assessing the impacts and governance challenges of large-scale climate interventions in the world’s oceans. Recently, he was part of a team of experts assembled by the Deep-Ocean Stewardship Initiative that were tasked with assessing and recommending paths on how to tackle this emerging challenge. Their new paper, Deep-sea impacts of climate interventions, which appears in the journal Science, explores the environmental risks of climate interventions, the current ocean governance challenges and what needs to be done to address them.

The paper outlines that the threats to the ocean, particularly the deep sea, have emerged from various human pressures, such as overfishing, biodiversity loss, plastic pollution, climate change, acidification, and deoxygenation. These threats stand to be compounded or exacerbated by ocean-based climate interventions. For example, a number of the interventions seek to capture and sequester carbon dioxide by depositing organic matter, or in some proposals inorganic matter, in order to capture carbon dioxide through biological and chemical processes. These proposed interventions pose potentially serious risks to ocean ecosystems by affecting connectivity, food supply and oxygen levels. Other techniques that target the ocean surface will likely impact the deep sea by transferring impacts such as acidification, reduced light, and trace toxic metal toxicity through the water. While these techniques remain experimental, the governance framework managing these activities is underdeveloped and highly fragmented.
Moving forward, Dr. Craik and his colleagues emphasize the importance of creating standards for assessing and making decisions around deploying various interventions. They explain that further research and policies are critical for reducing uncertainties about the impacts of these techniques and ensuring that international legal frameworks are updated to reflect and protect against risks to the deep sea.
“At the moment ocean governance is not keeping pace with the rapid technological developments in ocean-based climate interventions,” said Craik. “There is a tremendous need for proactive and precautionary law and policy to manage climate interventions in the interests of both humankind and ocean ecosystems.”
The urgency of the climate crisis demands an accelerated, focused effort on climate interventions, but not at the expense of ecosystems. The paper concludes by calling for an integrated approach. Scientists, industry leaders, and policymakers must work together to ensure that climate change mitigation efforts do not cause unintended harm to the vital ecosystems that support life on our planet.