Exploring Ocean Iron Fertilization: A Potential Climate Solution

With the need to urgently reduce atmospheric carbon dioxide (CO2), ocean iron fertilization (OIF) is being revisited as a possible method for marine carbon dioxide removal (mCDR). In a study published in Frontiers in Climate, researchers, including oceanographers from the University of Hawai‘i, examined OIF as a scalable, low-cost solution. OIF involves adding iron to the ocean’s surface to promote the growth of phytoplankton, which can absorb CO2. However, scientists caution that more research is needed to determine the technique’s effectiveness and potential ecological impacts.

Previous experiments with OIF showed that while it promotes plankton growth, it may not reduce atmospheric CO2 on the scale required to make a significant difference. Despite this uncertainty, the researchers stress that inaction is not an option, given the urgent need to address climate change. Controlled ocean trials are necessary to understand how long iron remains in the water, how much carbon can be stored, and what ecological changes may occur. As Professor Angelicque White from UH Mānoa highlights, responsible and transparent research is essential to determining whether OIF can buy time while efforts to reduce emissions continue.

The study outlines five key research activities, including field studies in the Pacific Ocean, modeling of OIF impacts, testing different iron delivery methods, and developing monitoring systems for carbon storage and ecological changes. The scientific community has also called for expanded research, with over 400 scientists supporting efforts to better understand mCDR techniques like OIF. The researchers emphasize that any deployment of OIF must be coupled with responsible governance and social science to ensure ethical and effective implementation.