Ocean Acidification

Diving Deep into Science at the Aquarium

Written by Molly Bogeberg, Marine Conservation Coordinator

A few members of the TNC Team and some of our fabulous volunteers participated in three days of energetic children, ocean education, and science fun at Seattle Aquarium’s Discover Science Weekend. The weekend kicked off with an evening of Lightening Talks staring local scientists from National Oceanic and Atmospheric Administration, the University of Washington, Washington Department of Fish and Wildlife, and Vulcan Inc. Each scientist was given a mere 5 minutes to explain their research. This meant that the scientists had to be creative and quick to get their point across. It was a fun way to dabble in local research and mingle with other science nerds!

 For the main Discover Science event, we had a booth to highlight our outreach materials on ocean acidification. Alongside the booth, our new ocean acidification infographic stood tall and provided talking points to help explain the complicated topic of ocean acidification, clearly. In addition to giving out our handy infographic booklets on ocean acidification to adults and coloring sheets to the little ones, we enticed kids to our table with a science experiment! Eager young scientists came with eyes bright and ready to learn.

For our experiment, we added CO2 to seawater using a Soda Streamer and then mixed in a pH indicator solution into normal seawater and the carbonated seawater to demonstrate how the chemistry of the water had been altered by CO2. With the addition of a green pH indicator, the color of the normal seawater retained the color of the pH indicator (green). The carbonated seawater, however, turned a bright orange after just a few drops of green pH indicator. We also used pH test strips to analyze the actual change in pH between the two samples. The changing color of the carbonated seawater elicited "ooos and ahhs" along with nods of understanding. You could really tell that the experiment and dialog helped the kids (and their parents) to grasp the concept of changing ocean conditions. After the experiment, we had kids roll a dice full of ways that they could help combat ocean acidification in their daily life. From civic action to walking to the farmer’s market to get groceries, the kids agreed that there were ways that they could help their favorite sea creatures!

Discover Science Weekend is my favorite outreach event that I get to participate in here at TNC. It really gives me hope to see kids excited about science and I love helping to inspire the next generation of ocean conservationists!

Learn more about our ocean work  

When a Global Issue is Felt Locally

 The impacts of climate change will vary from nation to nation, state to state, and city to city. Here in Washington, climate change is expected to increase fire frequency and severity in our forested areas, temperatures will continue to rise, coastal flooding will increase, and our oceans will become more acidic. Learn more about how climate change not only affects our marine environments but also plays an significant role in our local and national economies. Explore the infographic below.


Inforgraphic created by Erica Simek Sloniker, GIS & Visual Communications


Learn more about Ocean Acidification

A Rippling Effect: Ocean Acidification & Food Webs

From people to killer whales, to salmon, to zooplankton, the impacts from ocean acidification can affect a wide variety of organisms. As our oceans become more acidic, shelled organisms like oysters, zooplankton and pteropods have difficulty forming their hard exterior shell, which can lead to a decrease in their population. When populations of shelled organisms begin to decline, food for dependent species also begin to decline. Here off the shores of Washington, the Southern Resident killer whale mainly feeds on chinook salmon, eating around 385 lbs of fish a day! Where chinook salmon feed on small sea snails known as pteropods. As pteropods have already begun to feel the affects from ocean acidification, how will dependent species like chinook salmon and killer whales respond? 

Explore the infographic  below to see how ocean acidification affects other marine species throughout the food web. 

A Shift in Our Oceans

As more and more carbon dioxide enters our atmosphere, our natural environments respond differently. Where some regions may become hotter, and others may become cooler, our oceans become more acidic. Explore the infographic below to learn more about ocean acidification and how a small shift in ocean chemistry has a big impact for our marine organisms. 


Inforgraphic created by Erica Simek Sloniker, GIS & Visual Communications

There's Something in the Water: Ocean Acidification

Photos by Hannah Letinich, Volunteer Photography Editor
Written by Zoe van Duivenbode, Marketing Intern

The communities of Washington have a long, deep history with our state’s coastlines, from the Puget Sound to the Washington coast. Our marine waters are a foundation for our region’s economy, culture, and tourism. For centuries, tribes in Washington have relied on the harvest of shellfish for traditional ceremonies, subsistence use, trading and more recently, a source of income. Tourism is heavily dependent on our region’s seafood industry.  Pike Place Market alone attracts 10 million people annually to experience the market’s lively atmosphere and enjoy the country’s freshest seafood. In addition, much of our marine life depends on shellfish for food and habitat. Our region’s connection to shellfish is invaluable, which is why it is essential for our community to engage in a discussion as a whole in regard to the present and future challenges we face due to ocean acidification. 

Ocean acidification (OA) is a slow, long-term process that occurs as a result of the lowering of pH levels in seawater, creating a more acidic marine environment. The main driver of OA can be attributed to the amount of carbon dioxide in the atmosphere. Deforestation, land-based runoff and wastewater discharge also play into the acidifying process. Our oceans naturally absorb carbon dioxide, but after decades of rapid growth and fossil fuel burning, the natural absorption has accelerated, resulting in a more acidic environment with impacts to numerous marine species, including shellfish.

Several species of shellfish are particularly vulnerable to OA, especially larvae and juveniles. Their shells and hard external body parts require calcium carbonate, which is in shorter supply under acidic conditions. This results in a slower, more difficult development phase and increases the chance of mortality. According to the Washington Blue Ribbon Panel on OA, more than 30 percent of Puget Sound’s marine species are vulnerable to OA. In addition, OA is amplified in the Pacific Northwest because of several factors such as coastal upwelling and land-based runoff. Coastal upwelling is when carbon rich and acidic waters travel from the deep ocean and move into shallow waters. Due to the upwelling process, our seawater is naturally more acidic than other marine environments and in combination with OA, the impact of acidification is amplified.

Currently, TNC is working to cut carbon dioxide emission by reducing local land-based contributions to OA through green infrastructure development, installation of rain gardens and forest conservation. The combination of these efforts help to relieve the ocean of its enormous carbon load by decreasing the amount of atmospheric carbon dioxide and carbon rich runoff that flows into the Puget Sound. Although OA is a global issue, our region is among the first to experience its negative impacts. As a community that is so closely tied to the health of our ocean and shellfish, it is important for us to work together and do our part to mitigate the impacts of OA.