Increased Carbon Dioxide Affecting Washington Seawater

Helen Brandt, Ph.D. is a Whatcom County writer with an interest in marine science. She offers individual math-prep sessions for students in grades 3-6. helenbrandt@comcast.net

An endless stream of articles, blogs, and broadcasts argue about the veracity of scientists and the truth of their reports on climate change. Most people are content to relegate the issue to the category of “doubtful” and, in any case, consider it a potential problem for the far-off future.

Burning fossil fuels to generate electricity and run engines has another more immediate consequence that, until recently, has received little public attention. This article will discuss what happens when the oceans absorb carbon dioxide (CO2) from the atmosphere.

Measurements of levels of CO2 contained in ice cores indicate that the pre-industrial (1800s) carbon dioxide level was about 278 parts per million (ppm). By comparison the August 2010 reading at Mauna Loa, Hawaii was 388.15 ppm. This follows August readings of 385.91 ppm in 2008 and 384.15 ppm in 2009.

For the month of August 2010, atmospheric CO2 concentrations atop the Seattle Space Needle have tended to cluster around 390 ppm with some daily peaks in the 410-450 ppm range.1

The atmospheric concentrations of CO2 resulting from human activity are rising at a yearly rate about 100 times faster than has happened in the past 650,000 years.

The world’s oceans are absorbing from the atmosphere roughly 22 million tons of carbon dioxide every day. This has been a great help in reducing atmospheric CO2. But when CO2 enters seawater, the water becomes more acidic and there are fewer carbonate ions available for many growing organisms. The chemical changes that follow when carbon dioxide is dissolved into the ocean are long-known, straightforward processes.

Since the beginning of the Industrial Revolution, ocean acidity (hydrogen ion concentration) has increased by 30 percent. This change is about 100 times faster than any change in acidity in the last 20 million years. The question is how well organisms living in the oceans will be able to cope with their changing environment.

Senator Maria Cantwell chaired the Commerce Subcommittee hearing on ocean acidification. A report on acidification from the National Academy of Sciences National Research Council was presented to Congress. The April 2010 report notes that research studies on a number of marine organisms have shown that increasing CO2 increases seawater acidity and affects growth, reproduction and species survival.

Senator Cantwell also co-sponsored the 2009 Federal Ocean Acidification Research and Monitoring Act: It creates a comprehensive national ocean acidification research and monitoring program.

Warmer, more acidic oceans can destroy important fisheries and food chains in the Pacific Ocean, impacting Pacific Northwest icons like Pacific salmon. Understanding ocean acidification is critical to protecting Washington State’s marine life and the economy that depends on it.

Scientists from the National Oceanic and Atmospheric Administration are gathering data on the waters off the Washington coast, the inland waters of Puget Sound, the Salish Sea, and the ocean around Alaska. Research vessels and automated data collection buoys are measuring pH (acidity), pCO2 (partial pressure of carbon dioxide), temperatures and salinity.

Tatoosh Island lies off the Washington coast near the entrance to the Strait of Juan de Fuca and Neah Bay. Scientists there took 24,519 measurements over eight years, from 2000 to 2007, to provide the first dataset about changes in coastal pH in a northern temperate area. They found that acidity increased ten times faster than had been predicted from models and studies. Multiple factors are likely to have caused the increase.

Overall, as acidity increased, the numbers of organisms needing calcium carbonate decreased. But reactions across species were complex and suggest that changing pH will result in increased numbers of some organisms and decreased numbers of others.

Why are all these people concerned about the changes in ocean chemistry? There are several reasons. The increased atmospheric CO2 has come on rapidly, particularly in the past fifty years.

If we continue our current dependence on burning fossil fuels, the rate of change in ocean acidity from the beginning of the industrial revolution to the year 2100 will be greater than has occurred in hundreds of thousands of years.

Ocean organisms might adapt to slow changes that occur over thousands of years. But many organisms may be unable to adapt to the rapid changes. Temperate coastal waters have productive fisheries and rapid decreases in pH will have a severe impact on the marine food web.

Many ocean dwellers make shells or skeletons from a form of calcium carbonate (CaCO3), named aragonite. A more acidic ocean means there is less aragonite available for them to use. Clams, oysters and scallops need it. Their larval forms are particularly susceptible to increased acidity as they try to begin forming their first protective coverings.

Crabs use another form of calcium carbonate, calcite, to harden their outer covering. The National Marine Fisheries Service in Kodiak, Alaska, found that experimentally increasing acidity decreased the survival and growth of king crab larvae.

Organisms without shells, such as anemones and jellyfish, cannot regulate their internal pH and have to live with whatever pH level there is in the surrounding water. They may be especially susceptible to changes in ocean acidity.

A 2006 report prepared for Governor Gregoire found that shellfish harvests contributed 40.1 million dollars to the Washington economy. Likewise, salmon harvests in Washington waters contributed 9.5 million dollars to the economy.

Washington State shellfish harvests have contributed significantly to people’s livelihoods and dining pleasure. Many varieties of shellfish live in Washington waters, including clams, oysters, scallops and mussels.

There are more than ninety shellfish farms in Washington State, some on the coast and others on inland waters. Whatcom, Island and Skagit counties all have shellfish harvesting operations. Taylor Shellfish farm off Chuckanut Drive and the Lummi Business Council shellfish program are local examples

Growers on the Washington coast have seen declining harvests and failures of larvae to grow. Last year an emergency plan to save the oyster- industry in Washington and Oregon was developed by growers along with NOAA, the USDA and other interested parties.

Historically, Willapa Bay near Westport has been the largest oyster producing area on the West coast. But for four years natural sets of wild oysters have been virtually non-existent. Grant money was allocated to track down the causes of the problem. Research data are now being collected at farms in Wallapa Bay near Grayland and in the Hood Canal.

A May 2010 article2 reported on changes in Pacific Ocean water that passes through the Strait of Juan de Fuca and enters Puget Sound. The authors estimate that 25 to 50 percent of the acidification in Puget Sound is due to the Pacific waters. The remaining acidification is likely due to processes occurring within Puget Sound.

If certain organisms in Puget Sound such as oysters are already functioning close to their tolerance limit for low pH and low oxygen, increasing acidification from Pacific waters could cause them to die or be unable to reproduce.

Scientists at Western Washington University’s Shannon Point Center in Anacortes received in February 2010 a $557,000 National Science Foundation grant to experimentally alter seawater acidity by varying carbon dioxide levels and to assess the effects on plankton. Plankton are important because they are food for shrimp, scallops, oysters, clams and small fish. They are at the base of the marine food web.

Many Whatcom County fishers depend for their livelihood on catching salmon in Alaskan waters. Bellingham Cold Storage in 2009 warehoused 37 million pounds of frozen salmon, primarily from the cold Alaskan waters. Smoked salmon is a Northwest icon.

Young Alaska salmon eat small, 1-15 millimeter size creatures called pteropods. The word means “wing-footed.” The pteropods look like tiny snails that have an enlarged butterfly-like foot that they use as a paddle for swimming. To watch “Potato Chips” of the sea (pteropods) swimming go to: http://www.youtube.com/watch?v=67ezrD7QPhs

The cold waters off Alaska readily absorb carbon dioxide and have become more acidic. Consequently less calcium carbonate is available. This makes it more difficult for some pteropods to build their shells and diminishes their chances for survival.

More than 60 percent by weight of a juvenile pink salmon’s diet may consist of pteropods. When salmon cannot have their fill of pteropods, their harvest weight is reduced. A ten percent decrease in pteropod prey can result in a 20 percent decrease in the salmon’s harvest weight. So increasing levels of carbon dioxide can affect fisheries’ harvests and family incomes.

Coral reefs evoke images of tropical waters, a vacationer’s paradise. But around the world, millions of poor people depend on seafood from coral reefs for a significant portion of their needed protein.

The hard, obvious part of coral is formed from calcium and carbonate ions in the seawater. As the water becomes more acidic there is less carbonate available for the coral to use. In fact, as waters become increasingly acidic, the hard coral can actually dissolve.

There are also coral reefs in cold waters. Scientists recently discovered deep coral reefs thirty miles west of Grays Harbor. These reefs are formed by glass sponges and are teeming with sardines, crabs, prawns, and rockfish.

Cold-water coral ecosystems provide habitat, feeding grounds, and nursery areas for many deep-water organisms, including commercial fish species. As oceans continue to absorb carbon dioxide during this century, by 2100 most cold-water corals will be exposed to corrosive waters.

If we continue with “business as usual” burning fossil fuels, the atmospheric CO2 will reach 780 ppm near the end of this century. The effects on ocean productivity will be significant but unpredictable.

Over half the world’s population today depends on the sea as their primary source of protein. Who is responsible for the wellbeing of the planet’s life-sustaining ocean systems that the unborn generations will need? At one time, we did not realize the impacts from using fossil fuels. But now that the impacts are increasingly clear, what is our responsibility?

The discussion of the ethics involved in fossil fuel use is occurring within some religious groups. For example, the World Council of Churches, the Jewish Climate Initiative, the Roman Catholic Church, the Evangelical Climate Initiative, the Muslim Associations for Climate Change Action, and the Buddhist Climate Project have issued statements on environmental responsibilities.

Other religious groups tend to focus on individual salvation and the imminent end of the world rather than on environmental ethics.

Discussions in the media reflect immediate economic impacts such as increased costs or job losses. So the public discussion about the ethics of continued dependence on fossil fuel use tends to be bypassed.

On May 29, 2009, the University of Washington School of Law presented “Three Degrees – The Law of Climate Change and Human Rights Conference.” Dr. Henry Shue, professor of Ethics and Public Life at Cornell University presented a keynote address: “Vulnerability and Protection – Climate and Rights.” The address is available online at the Washington State Public Affairs TV network.3

Shue presents an analysis of the ethical responsibility we have with regard to the continued production of carbon dioxide from burning fossil fuels. Although his focus is on the climate impacts from fossil fuels, his analysis applies equally to carbon dioxide’s effects on ocean chemistry.

Shue notes that most of today’s atmospheric carbon dioxide is the result of burning fossil fuels during the twentieth century. During much of that time people generally did not realize the consequences of their activities. But now that the effects are apparent, what are the ethics involved in continuing to add to the total CO2 load in the atmosphere?

Shue distinguishes between those who must use fossil fuels in order to survive and those for whom it is a matter of choice and convenience, those for whom alternatives are available.

For example, in some places, cooking has to be done by burning wood or coal for fuel. There are no practical alternatives. But in developed countries, cooking could potentially be done using electricity from solar, tidal or wind power.

In poor countries coal may be the only way to heat flimsy homes in the winter. In North America and Europe, the possibility exists to increase insulation, use more efficient gas furnaces, heat with “green” electricity, and effectively reduce the amount of fossil fuels consumed.

Shue’s analysis does not lead to simple answers. Instead it provides a way of examining the ethical implications of our daily choices and way of life.

In 2008, 155 scientists from 26 countries met in Monaco to discuss the urgent problem of acidification of the world’s oceans. They issued the Monaco Declaration, which expressed their consensus that the current 3 percent yearly increases in CO2 emissions must be reversed by 2020 if severe damage to the oceans is to be avoided.

Already some coastal waters in the spring are corrosive to certain bottom-dwelling creatures. Before midcentury, if current emissions levels continue, coral reefs will be eroding faster than they are building up.

Add another 60 ppm to today’s atmospheric CO2 level and large areas of the polar oceans will become corrosive to the shells of important organisms.

So where does Whatcom County stand with regard to the changes in seawater chemistry affecting our Pacific shores? Unless significant reductions in the use of fossil fuels to run engines and generate electricity in technologically developed countries occur within the next ten years, it is likely that the sea will be unable to produce for today’s children the harvests Northwest people have depended on for millennia.

Dr. Richard Feely, of the National Oceanic and Atmospheric Administration based in Seattle, has said, “Because of the very clear potential for ocean-wide impacts of ocean acidification at all levels of the marine ecosystem, from the tiniest phytoplankton to zooplankton to fish and shellfish, we can expect to see significant impacts that are of immense importance to humankind.”⁴ §