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Turning the tide against climate change

Ocean science is taking a lead in determining whether we can and should pursue the options laid out in a recent report about what is known as “ocean-based carbon dioxide removal.”

President Emmanuel Macron of France speaks at the Lisbon Oceanarium, in Lisbon on June 30, as part of the United Nations Ocean Conference, which explored how to restore the health of the ocean.LUDOVIC MARIN/AFP via Getty Images

For much of human history, the ocean was viewed as a source of limitless bounty that we could tap at will, but that remained remote and unassailable by human action. Yet as humanity’s influence over the planet has grown, the ocean has come to be seen as a victim suffering from a long litany of our degrading activities.

But it is time to change our view of the ocean and see it for what it is: a resource with the power to help blunt or even reverse the climate crisis. The ocean’s immense size and natural processes already have protected the planet by absorbing more than 90 percent of the heat generated by human-caused greenhouse gas emissions. It has also absorbed about one quarter of our carbon dioxide emissions.


And it could potentially do much more, if we help it, but only if we do so intelligently and with care.

Last month, I led a delegation from the Woods Hole Oceanographic Institution to Lisbon and the United Nations Ocean Conference, the highest-level international gathering of world leaders in government, science, advocacy, finance, and philanthropy focused on the ocean. What we heard in Lisbon was a clarion call to action: We must act now, and we must act decisively.

But there was also another theme that we heard loud and clear. People around the world look increasingly to science for answers. Ocean science can help ensure the long-term sustainability of global society, possibly by making use of the solutions the ocean itself offers us.

We don’t have all the answers, but this is a mantle that science must take up to identify our options to mitigate climate change, evaluate their effectiveness, and understand their impacts. Ocean science is taking a lead in determining whether we can and should pursue the options laid out in a recent report by the National Academies of Science, Engineering, and Medicine about what is known as “ocean-based carbon dioxide removal.” These include such strategies as adding nutrients to key places in the open ocean to stimulate phytoplankton growth, making seawater more alkaline to combat the acidification of the ocean, growing seaweed to consume carbon dioxide, as well as protecting and restoring coastal ecosystems such as salt marshes and mangroves. All of these can help reproduce and enhance naturally occurring processes and reduce greenhouse gases in the atmosphere. These become even more important now that the Supreme Court has limited the Environmental Protection Agency’s ability to regulate carbon emissions, though they cannot replace emissions cuts.


As part of these efforts, our institution is exploring development of what we call an Ocean Vital Signs Network, which would equip a volume of the ocean roughly twice the size of Texas and up to 5,000 meters (3 miles) deep containing an unprecedented scale of oceanographic moorings, free-swimming autonomous underwater vehicles, drifting floats and sensors, and other cutting-edge technological innovations, all focused on scientifically documenting how the ocean takes up and stores carbon.

In addition to leading a new era of deep ocean discovery and exploration, this network would also be an important test bed, where scientists could implement carefully designed and monitored experiments to determine the efficacy and impact of large-scale carbon dioxide removal concepts. It would also help support the continued growth of the Blue Economy — industries and jobs that rely on the ocean and a market that’s growing twice as fast as the economy.


Another repeated message we heard in Lisbon is that science must act with care and humility in developing solutions. The ocean is our planet’s life-support system and anything we do must respect this vital role it plays. During the meeting, two members of our team presented a code of conduct to guide scientific inquiry into removing carbon dioxide from the atmosphere by stimulating phytoplankton growth. This meeting gave us and many others, including members of the American Geophysical Union, the largest professional society of Earth and space scientists in the world, a roadmap to converge our efforts and guide future research.

Our path will not be easy, but Lisbon gave us the opportunity to take the first steps. Now is the time to help change the ocean’s narrative and consider leveraging the ocean’s size and power to help us turn the tide against the climate crisis.

Peter de Menocal is president and director of the Woods Hole Oceanographic Institution.