Leading the way on ocean acidification
This summer, Monterey Bay Aquarium and Monterey Bay National Marine Sanctuary hosted Big Blue Live – an unprecedented series of live natural history broadcasts from PBS and the BBC. Big Blue Live highlighted the remarkable marine life that gathers in Monterey Bay, and celebrated the recovery of the bay as an ocean conservation success story of global significance. Many conservation efforts contribute to the health of the bay and our ocean planet, and we’eve highlighted several in a series of guest commentaries. This comes from Lindley Mease, a senior research analyst , and Kristen Weiss, an early career fellow – both at the Center for Ocean Solutions. The Center is a collaboration among the Stanford Woods Institute for the Environment and Hopkins Marine Station of Stanford University, the Aquarium and the Monterey Bay Aquarium Research Institute.
MPAs often aim to protect ocean habitats from local pressures, from fishing to offshore oil drilling. Research now suggests that they’re also an ideal way to address some local impacts of climate change. While resource managers might not be able to directly manage fossil fuel emissions, they can implement local mitigation and adaptation measures that help protect coastal ecosystems from impacts such as hypoxia (oxygen-deficient water) and ocean acidification.
As fossil fuel emissions steadily increase, the ocean is absorbing proportionately larger and larger amounts of CO2, which is gradually lowering the pH of the oceans. Often called “the other CO2 problem”, ocean acidification has already been shown to harm a number of species found in California’s MPAs. Planktonic pteropods (also known as “sea butterflies”), shellfish like abalone and oysters, and oxygen-producing phytoplankton are among the organisms affected by increasing acidity. Many of these species are integral to ocean food webs.
More change to come
California’s waters have acidified by 26% during the last century and are projected to become three to four times more acidic by 2100. While the largest contributor to ocean acidification in California is the global increase in atmospheric CO2, there are also potential local drivers of acidification and hypoxia, such as local deposition of nitrous oxides and sulfur oxides from power plants, and land-based runoff that includes nutrients and heavy metals. These drivers may create ‘hotspots’ of acidity that managers can target with location-specific action.
Research from the Center for Ocean Solutions (COS) suggests that MPAs may be an effective vehicle for addressing some of the place-based drivers and impacts of these threats because MPAs already serve to safeguard critical species and coordinate management capacity. And they’re “sentinel sites” for monitoring and protecting the species and habitats identified as critically important for long-term ecosystem functioning and resilience.
To adequately protect marine species and ecosystems from ocean acidification, we need to increase our scientific understanding of acidification at multiple scales, encourage management adaptability, and strengthen state habitat protections through existing environmental legislation. We also need to to enhance the connectivity and resilience of California’s extensive MPA network.
The state’s Ocean Science Trust, as directed by the Ocean Protection Council, is supporting the West Coast Ocean Acidification and Hypoxia Panel, a comprehensive initiative to inform state and regional ocean acidification policy and management. The panel is providing guidance on potential management actions and science needs to address local acidification and has engaged government, academic and industry partners. Other bodies are beginning to explore how they can address acidification by using air and water quality laws to mitigate potentially significant local pollution sources.
Over the past decade, as our scientific understanding of ocean acidification has evolved and concern about its potential far-reaching impacts has grown, there’s been more attention paid to how to strategically adapt to changing ocean chemistry. Non-governmental organizations and academic institutions are organizing in a big way to highlight the issue at December’s United Nations climate conference in Paris. Ocean managers must be ready to implement both mitigation and adaptation measures to tackle this complex challenge.
Monterey Bay leads the way
The Sanctuary is well suited to play a leadership role. Monitoring and scientific research in the area is ongoing, the Sanctuary is home to a number of protected and iconic species, and existing habitat protection frameworks could be adapted to address climate change impacts more directly.
Sanctuary staff are working to communicate with the public about the causes and impacts of ocean acidification, and with communities to develop climate action plans. The Center for Ocean Solutions, Monterey Bay Aquarium Research Institute (MBARI) and Hopkins Marine Station are monitoring water quality and ocean acidification in the bay using the Center’s kelp forest array and MBARI’s environmental sample processors.
MBARI has also been testing marine species’ responses to ambient and elevated CO2 conditions with its Free Ocean CO2 Enrichment Experiment, a set of underwater chambers that allow scientists to perform ocean acidification experiments within the marine environment.
In addition, we’re collaborating through the Marine Biodiversity Observation Network – a new project that’s developing innovative technologies to monitor and manage marine species. These site-specific data should help managers make more informed decisions about resource use and conservation in the bay, and provide quicker feedback about environmental responses to natural or human-based changes that may warrant management intervention.
Monterey Bay’s most treasured marine features – from its lush kelp forests and rich fisheries to migratory whale and sea bird species – depend on a healthy, productive ecosystem. By actively protecting the bay from local sources of pollution, and by understanding ocean acidification in our own backyard, we can help ensure that these and other ecological communities are more resilient to global level changes now and into the future.