THE CHANGING PACIFIC
Exploring Ocean Acidification along the California Current
Hello!
Hello! I’m a sea otter and I live right here on the Pacific coast. I can be found in kelp beds and other shallow coastal habitats. You may have seen me forming a raft together with my family as we bob on the waves. Or maybe you’ve spotted me splashing as I dive for food to feed my pups. As top predators, otters like me help keep our local marine environment in balance by feeding on sea urchins!
Unfortunately, my home and food source are under threat because of climate change.
CLIMATE CHANGE
The burning of fossil fuels releases carbon dioxide (CO 2 ) and other greenhouse gasses into our atmosphere, where it forms a heat-trapping blanket around the earth. As we emit more CO 2 , the blanket gets thicker resulting in global warming and climate change. The world is now warming faster than at any point in recorded history.
The ocean has absorbed approximately 90% of excess heat and 25% of the carbon dioxide emissions released into the atmosphere by humans.
Increased carbon pollution has consequences for our ocean.
OCEAN ACIDIFICATION
As we continue to release CO 2 into the atmosphere through human activities such as burning fossil fuels, the ocean is forced to absorb more and more carbon.
When CO 2 combines with seawater, it sets off a chemical reaction that makes seawater more acidified. We call this process ocean acidification or "OA".
The chemical reaction that occurs lowers the pH , a measure of how acidic or alkaline the seawater is. This reaction also decreases the availability of calcium carbonate, a building block that many species like shellfish, finfish, coral and pteropods need to grow, reproduce, and thrive. OA can also affect the "energy budget" of some marine life, impacting their ability to perform other necessary tasks. You can learn more about the chemical reaction that produces OA at NOAA Ocean Acidification Program's website .
Ocean acidification is especially detrimental to species that rely upon calcium carbonate to make their shells and skeletons. This includes phytoplankton, which form the base of our marine food web.
In the presence of other climate stressors, ocean acidification makes it harder for species to bounce back from change and environmental harms.
LOCAL TRENDS
Along the West Coast, the combined effects of climate change and ocean acidification are threatening the growth and survival of culturally and commercially important species. In fact, the West Coast of North America is acidifying faster than anywhere else in the world, which has consequences for marine resources, food security and economies, cultural practices and traditions.
Upwelling brings pH down.
West Coast water is naturally more acidic due to upwelling, a natural process that causes deep ocean water to rise to the surface as winds push water away from the shore. The water that upwelling brings from the deep is cold, old, contains more carbon dioxide, and is rich in nutrients. All of these properties can result in a lower pH.
West Coast water is warming.
The Pacific coast has already experienced multiple marine heatwaves. The most famous marine heat wave, known as “the blob”, occured between 2014-2015.
This event covered more than 3.5 million square miles from Mexico to Alaska, an area larger than the contiguous United States, and resulted in the temporary closure of commercial crab fisheries and recreational razor clam fisheries. These marine heat waves are projected to increase in frequency.
Wastewater and land pollution make conditions worse.
In nearshore and coastal environments, local sources of land-based pollution like nitrates, wastewater, stormwater, and agricultural run-off contribute to coastal acidification and low oxygen content.
These combined conditions put extra stress on a wide range of marine animals from crabs to fish, which disrupts seasonal harvests and catch potential.
We are already seeing impacts on species and food webs!
Increased ocean acidification has resulted in the death of baby oysters in hatcheries in the Pacific Northwest and has significantly disrupted the shellfish aquaculture industry.
Additionally, OA has impacted growth of Dungeness crab and pteropods – a foundational food source for salmon and orca.
In the future – if humans don't take actions to reduce global carbon emissions – ocean acidification will increase in intensity, extent, and duration in the waters along the West Coast.
IMPACT ON HUMANS
"Washington state has already experienced the ravages of climate change and it is impacting the health of our ocean, our economy, and our communities. Our decisions matter and it is critical we act fast to reduce carbon pollution.”- Governor Jay Inslee, Washington State, USA
The West Coast region is home to a wide range of ecosystems, from San Diego to the San Juan Islands, that provide important ecosystem services and bring economic, recreational, and cultural value for local coastal communities and the entire United States.
Since time immemorial, Indigenous peoples have made the rich ocean and marine coastlines of the West Coast their home. Abundant salmon, halibut, whales, crab, oysters, and clams remain an important foundation in traditional ways of life for hundreds of Tribes and First Nations along the Pacific Coast.
Dungeness crab is one of the most iconic and economically important fisheries in the region, valued at over $50 million annually in Oregon alone. Geoduck is Washington’s most valuable seafood export and shellfish growers generate over 2,700 jobs in the state. California’s wild-caught spot prawn fishery lands an average of 250,000 pounds per year.
The entire West Coast benefits from a $270 million dollar oyster growing industry. Traditional razor clam and salmon harvests hold spiritual and cultural significance for many Tribal nations.
The future of these fisheries and ecosystems, and the communities that rely on them, will depend on their ability to adapt to climate change and ocean acidification.
“Fishing is key to the Makah. Since time immemorial the Makah people, our culture, and ceremonies have been dependent on resources from the ocean. The Makah Tribe is developing an action plan to address these threats to protect Makah’s treaty reserved rights.” - Chairman John Ides, Sr. of the Makah Tribe
Communities and governments along the West Coast are working together to monitor and respond to the threat of ocean acidification and the mounting climate emergency.
These are just a few examples of projects and communities along the West Coast that are advancing OA knowledge and dedicated to climate-ocean health:
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California Current Acidification Network
California Current Acidification Network . Click to expand.
The California Current Acidification Network (C-CAN) is a collaboration of interdisciplinary scientists, resource managers, industry and others from local, state, federal and tribal levels dedicated to advancing the understanding of ocean acidification and its effects on the biological resources of the US west coast. C-CAN works in cooperation with Northwest Association of Networked Ocean Observing Systems (NANOOS), of the Integrated Ocean Observing System (IOOS) Regional Associations, and many other like-minded groups.
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West Coast Ocean Alliance
West Coast Ocean Alliance . Click to expand.
The West Coast Ocean Alliance is a Regional Ocean Partnership that aims to harmonize the efforts of state, tribal, and federal government partners within an inclusive, non-regulatory framework. Current OA projects include the West Coast Ocean Data Portal and the development of a west-coast-wide OA indicator in their West Coast Ocean Health Dashboard project.
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Olympic Coast OA Sentinel Site
Olympic Coast OA Sentinel Site. Click to expand.
The Ocean Acidification Sentinel Site (OASeS) on the Olympic Coast of Washington focuses on ocean acidification science and identifies trends in carbonate chemistry and hypoxia. The sentinel site is used to inform resource managers and coastal communities by telling the story of OA and its impacts on Washington coastal marine resources, coastal cultures, communities, and economies. OASeS seeks to ensure that the Olympic Coast is well prepared for changing ocean conditions, with research and management actions in place.
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Olympic Regional OA Vulnerability Assessment
Olympic Regional OA Vulnerability Assessment. Click to expand.
Washington Sea Grant, in partnership with the Olympic Coast Treaty Tribes, federal and academic scientists and coastal managers, is conducting the Olympic Regional OA Vulnerability Assessment to understand and plan for the impacts of ocean change to Tribal community well-being.
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Washington Ocean Acidification Center
Washington Ocean Acidification Center. Click to expand.
The Washington Ocean Acidification Center at the University of Washington was created by the State Legislature in 2013 to sustain a comprehensive ocean acidification monitoring network to measure trends in local acidification conditions and related biological responses, among other tasks.
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Hatfield Marine Science Center and Newport Hydrological Line
Hatfield Marine Science Center and Newport Hydrological Line. Click to expand.
Research at Oregon State University’s Hatfield Marine Science Center (HMSC) has supported Pacific oyster farmers and hatcheries for over 80 years. In the Langdon Lab, we undertake a range of research projects that support sustainable aquaculture in Oregon and the U.S. West Coast, including projects related to ocean acidification. The Newport Hydrological Line is conducting sentinel site research that gives us insight into the ocean and how it’s changing, providing barometer of OA and hypoxia.
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California Ocean Science Trust
California Ocean Science Trust . Click to expand.
The California Ocean Science Trust serves as Science Advisor to the Ocean Protection Council, a Cabinet-level state body that works jointly with state and federal agencies, NGOs, Tribes and the public to ensure that California maintains healthy, resilient, and productive ocean and coastal ecosystems. The California Ocean Science Trust leads the ongoing project: Assessing Community Vulnerability to Ocean Acidification Across the California Current Ecosystem.
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Southern California Coastal Water Research Project
Southern California Coastal Water Research Project. Click to expand.
The Southern California Coastal Water Research Project (SCCWRP) is part of an international community of researchers working to evaluate the effectiveness of multiple possible management solutions for reducing the impacts of acidification and hypoxia on coastal ecosystems.
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University of California Davis
University of California Davis . Click to expand.
The University of California Davis Coastal and Marine Sciences Institute supports an interdisciplinary ocean acidification research program. The Bodega Ocean Acidification Research Program (BOAR) focuses on how changing seawater chemistry impacts ecologically, culturally, and economically important species along the West Coast.
WHAT IS BEING DONE?
The good news is we can take action to halt carbon emissions - the number one cause of ocean acidification – and ensure our ocean and coastal communities are resilient in the face of climate-ocean change.
Federal Action
The United States government is increasingly placing emphasis on climate and ocean change policies. The FOARAM Act (2009) brought ocean acidification into the national spotlight by forming NOAA’s Ocean Acidification Program to direct ocean acidification policy, research, and response across the U.S. Significantly, the U.S. released a National OA Action Plan (2023) to guide further science, research, policy and investments domestically and internationally.
The Inflation Reduction Act (2022) features the most expansive investment in US climate projects ever passed. The new Ocean Climate Action Plan (2023) outlines goals that integrate the Federal Government’s approach to climate and ocean science, conservation and fisheries management.
Congresswoman Bonamici (OR) and Senator Cantwell (WA) have sponsored and supported OA legislation including the “ Coastal Communities Ocean Acidification Act of 2023 ”.
Regional Coordination
From 2013 to 2016, Ocean Science Trust convened the West Coast Ocean Acidification and Hypoxia Science Panel , comprised of 20 leading experts. The Panel developed a body of products that identified science-based options to address OAH at the regional and local levels.
As part of the Pacific Coast Collaborative (PCC), the Governors of Washington, Oregon, California and the Premier of British Columbia support a regional partnership to advance climate policies, build a clean energy economy and infrastructure, and increase West Coast resilience to impacts already occurring. The PCC has an active OA and Hypoxia working group that for 10 years has led the country in developing policy responses to OA.
Together, these states are leading the world in OA policy and response by launching the International Alliance to Combat Ocean Acidification in 2016 – and encouraging other governments to create OA Action Plans .
"Inaction is not an option, which is why we are committed to a zero-carbon emissions economy that will stem the tide of alarming climate-related changes in our oceans. We are committed to implementing California’s Ocean Acidification Action Plan to adapt and build resiliency against existing climate change threats." - Secretary Wade Crowfoot, California Natural Resources Agency
State and Local Policy Response
Each state on the West Coast has created an OA Action Plan that identifies and prioritizes strategies that support seafood economies and coastal communities. Additionally, each state has strong climate policies like California’s Cap and Trade Program , Washington’s Climate Commitment Act and Oregon’s Climate Action Commission .
Examples of OA Action Plans and Activities Along the Pacific Coast (State, Tribal, Municipal).
Aquarium Leadership
The Aquarium Conservation Partnership (ACP) is a coalition of U.S. aquariums working to conserve our ocean and freshwater ecosystems. ACP members work together to combat climate change by reducing emissions from operations through a joint commitment to achieve carbon neutrality , advancing policies that lead to a more resilient and equitable future for people and the planet, and inspiring audiences to take climate action.
The West Coast is home to these spectacular members of the Aquarium Conservation Partnership.
Washington : Seattle Aquarium and Point Defiance Zoo and Aquarium
Oregon : Oregon Coast Aquarium
California : UC San Diego Birch Aquarium , Aquarium of the Pacific , California Academy of Sciences , Cabrillo Marine Aquarium , Fresno Chaffee Zoo , Monterey Bay Aquarium
HOW CAN WE HELP?
In the face of climate change, we have a collective responsibility to protect our planet and secure a sustainable future for generations to come. Together, we can embark on a journey towards a healthier, less carbon intensive, and more sustainable world.
Here are some empowering actions that we can each take to reduce carbon emissions and address climate change:
1) Use your voice!
- Vote for the Ocean . By exercising your right to vote — from national to local, all the way down the ballot — you can help address climate change and protect the ocean, the animals that live there, and the people who depend on it.
- Contact your representatives ! They need to hear that voters care about reducing carbon emissions, protecting marine habitats, and adapting to the changes already in motion.
2) Wave goodbye to carbon!
- Support policies that transition society to large-scale clean energy production, set low-carbon fuel standards, ensure energy efficiency in buildings, hold emitters accountable, and lower emissions across our shipping and supply chains.
- Save money. Save energy. Save the planet. Clean energy and energy-efficient consumer choices are available now, and the U.S. government is working to make them more affordable and accessible.
3) Dive into an ocean-friendly routine!
- Make climate-and-ocean-friendly choices including reducing your food waste, buying in smaller quantities, eating sustainable seafood , and avoiding single-use plastic . These actions, together with tackling our emissions, can preserve the health of our ocean for future generations.
- Get more involved! Participate in community science programs, volunteer with local conservation organizations, or reflect on your personal relationship with the ocean. What makes your local marine ecosystem special or sacred to you?
4) Champion others who are doing the work
- Spread the word! Share the work of local and Indigenous communities, NGOs, or research institutions that are addressing climate-ocean change. Donate to an environmental non-profit.
- Support climate-friendly businesses and organizations who are committed to reducing carbon emissions and investing in sustainable business practices, such as your local aquarium.
Thanks for stopping by!
We all have a role to play to combat climate change and ensure the health of our ocean!
The good news is we can advance science, implement policies and take local actions that reduce the causes of OA and support the resilience of marine ecosystems and coastal communities we love.
Learn more about international , domestic and regional efforts to combat OA. Join our networks!
“The story of the ocean and the story of humanity are one and the same… being the people of this blue planet is our most profound privilege and power.” - Poet Laureate Amanda Gorman, Ode to Our Ocean
This StoryMap was created in collaboration between the OA Alliance , ACP , NOAA OAP , and C-CAN .