Falling pH and Rising Momentum: Taking Action on Ocean Acidification

This is the third article of Currents feature series on Climate, to read more on the climate conversation, check out our previous posts on youth perspectives and climate litigation.

Coastal ecosystems on Washington’s Olympic coast and worldwide are vulnerable to the impacts of ocean acidification. Scientists are monitoring changes in ocean chemistry and impacts to commercially and ecologically important species, like Dungeness crab, oysters, and salmon. (Photo credit: Charlotte Dohrn)


Ocean acidification, infamously called climate change’s evil twin, has earned its share of bad press lately. Mainstream media like The Guardian and the Los Angeles Times are covering new and discouraging findings – acidified ocean waters along the Pacific Northwest coast are harming the shells and sensory organs of valuable Dungeness crab, and waters off the California coast are acidifying twice as fast as the global ocean.

Ocean acidification is a complicated phenomenon – in brief, the world’s atmosphere and oceans are linked through physical and chemical cycles. Atmospheric carbon dioxide (CO2) is absorbed by ocean water, setting off a chain of chemical reactions. Due to increased carbon in the atmosphere from fossil fuel burning, oceans are taking up more CO2, which drives down pH. Lower pH means that waters are more corrosive. Increasingly acidified waters threaten coastal economies in the United States from Alaska to the Caribbean.

Ocean acidification is caused by excess atmospheric CO2 from fossil fuel emissions making its way into the ocean, where chemical reactions increase acidity of the water. (Source: Seattle Aquarium)


After the world learned about the impacts of acidification from oyster growers on the Washington coast, scientists, policymakers, and resource managers hurried to take action. Grassroots connections turned into “knowledge-to-action” networks, providing invaluable infrastructure for building understanding and disseminating research across scientific, management, and governance actors. The International Alliance to Combat Ocean Acidification (OA Alliance) has been at the forefront of this effort in recent years. The OA Alliance works to move the needle on how the world is planning for and taking action to address climate change’s impact on oceans.

We caught up with Jessie Turner, director of the OA Alliance, to learn more about this rising tide of action-taking. Turner describes some of the challenges the OA Alliance is working to address: “Just as some ocean acidification science is in beginning stages, policy response and management discussions are also in beginning stages. This can be a challenging place to start discussions… there is not a lot of precedent to look to. This is why early and frequent collaborations across government, scientists, and impacted communities at a state and regional level are so critical.”

In September 2019, we had the opportunity to work with the OA Alliance on a workshop to promote knowledge sharing and collaboration between east coast and west coast states, and build momentum for state action plans. Held at the New York Aquarium, the workshop included leadership from governors’ offices, state and federal agencies, ocean acidification task forces and monitoring networks, nonprofits, and research entities. During breakout sessions, scientists and managers shared stories and exchanged ideas for taking action in their states and communities. Efforts included reducing nutrient inputs in nearshore waters, identifying industry and legislative partners, protecting seagrass and investigating carbon storage potential, and building monitoring programs. Participants were frank about the challenges they face – including funding, political support, issue awareness, data gaps – and were eager to share potential solutions.

State-level resource managers and other leaders convened in New York at a workshop to share lessons learned and best practices for taking state-level action to address ocean acidification. (Photo credit: Hanna Miller)


We are continuing to work with the OA Alliance to help distill the ideas that bubbled up at the workshop, such as the power of local story-telling, and to develop additional communication tools that can help guide groups at different stages of the planning and action-taking process. 

An epicenter for the impacts of ocean acidification and the home of leading research, the U.S. West Coast provides an example of the power of collaboration. Washington, Oregon, and California have developed ocean acidification action plans and have strong state-level support for science and policy efforts. Institutions like the Washington Ocean Acidification Center create a hub for researchers, policymakers, and industry working to understand and mitigate the impacts of acidification. During the workshop, leaders from these states shared lessons learned from their endeavours, while other states shared progress on their initiatives or sought input on building momentum.

We asked Jessie Turner about the barriers to getting started that she most frequently hears. She described: “Often times, governments already have climate action plans and adaptation measures, coral reef monitoring and restoration strategies, or other ocean ecosystem management policies in place, but they don’t have a lot of information about ocean acidification. It’s important to share examples of ocean acidification being incorporated into existing management strategies and monitoring systems. This includes efforts related to ocean observations, water quality, stormwater, wastewater or other sources of pollution or land-based run-off.”

She highlighted the importance of local research: “Decision makers are curious to learn more about the potential impacts to species that are important within their own region. The more information that scientists and policy makers have about the condition and variability of ocean and coastal waters, the better.”

The shellfish industry was the first to call attention to the impacts of ocean acidification, when corrosive waters caused hatchery failures. Left, oysters are grown to market size on the tidelands. Native shellfish, like the tiny Olympia oyster on the right, are also vulnerable. (Photo credit: Charlotte Dohrn)


Projections for the world’s ocean and climate system under current emissions trajectories are extreme, but the OA Alliance and its members and partners have a lot to celebrate this year. In addition to the workshop and several other conventions, including during the United Nations Climate Week and at COP25, the OA Alliance supported the development of 15 new action plans in 2019.

Turner writes: “Building bridges between ocean and climate policy leads, resource managers, and scientists plays an important role in facilitating the actions needed to protect ocean resources and coastal communities. It’s been a privilege to work with so many dedicated and passionate actors who all have a role to play and, through the Alliance, help to focus discussion around a common goal—the creation of state, regional or national OA Action Plans.” In the coming year, the OA Alliance will continue efforts to, as Turner describes, “keep ocean acidification, impacts and actions, a focus point at the nexus of the climate and ocean.”

The scope of the ocean acidification problem is daunting and the consequences of inaction are severe. As we watch our federal government and others avoid or struggle to take action on the climate crisis, it is heartening to see momentum at local and regional scales to mitigate and adapt to climate change. The OA Alliance and others working on acidification are amplifying the call to reduce global and local CO2 emissions – the anthropogenic elephant in the room most responsible for our acidifying waters.