Report: Northwest Ocean Acidification

Sightline details the hidden costs of carbon dioxide pollution.
This post is part of the research project: Northwest Ocean Acidification
evanbdudley, flickr

evanbdudley, flickr

Editor’s note: This primer is also available in a two-page summary format.

Tiny sea butterflies dissolve before researchers’ eyes. Baby oysters die by the tankful. Sea urchins grow deformed. These are a few consequences of raising marine creatures in increasingly corrosive water. And they could preview what’s in store for the Northwest as carbon dioxide pollution from cars, power plants, and other human sources changes the chemistry of our marine waters.

Oceans—and their salt-water extensions like Puget Sound—play an enormous role in our region’s prosperity. A new report from Sightline—Northwest Ocean Acidification: The Hidden Costs of Fossil Fuel Pollution—details how years of addiction to fossil fuel pollution are putting that resource at risk.

You can read the full report here, but here are some basics:

What is ocean acidification?

Every day, the oceans do us a huge favor by absorbing a third of the carbon dioxide we release into the atmosphere—emissions that would otherwise make global warming worse. But rising fossil fuel pollution has another cost: as oceans absorb more carbon dioxide, they become more acidic and corrosive. The process also robs seawater of carbonate ions, a key building block for shells and skeletons and an ingredient so essential to ocean life that some call it “the soil of the marine world.”

Is it happening now?

cswto, flickr

Just five years ago, scientists believed the effects of ocean acidification would be confined to deep, offshore ocean waters for decades—until oceanographers started hunting for it off the Pacific Coast. In the last few years, they’ve found evidence of acidification nearly everwhere they looked, from British Columbia to Baja California to Washington’s Puget Sound.

What can the Northwest expect?

Some creatures will do fine in a more corrosive ocean. Others will die. In laboratory experiments, the animals that struggle or dissolve range from mussels to endangered abalone to cornerstones of the marine food web like krill and pteropods—tiny sea snails that make up more than half of the diet of some young Alaskan pink salmon. Yet some crustaceans have developed thicker shells, and some eelgrass grew more abundantly. Northwest researchers are working hard to understand how important local species will fare.

What are the potential economic consequences?

Michael @ NW Lens, flickr

Among commercially valuable species, shellfish appear to be the most vulnerable. In recent years, two of the Northwest’s three major oyster hatcheries have had massive die-offs, some of which have been linked to acidified seawater. In Washington’s Willapa Bay, oysters have largely failed to reproduce in the wild for the last six years.

It’s unclear whether ocean acidification will directly affect salmon or pollock or other prized finfish, but it could disrupt food webs and make their prey less abundant. The executive director of Alaska’s largest commercial fishing organization, Mark Vinsel, ranked his concerns about ocean acidification this way: “I’d say probably on a scale of 1 to 10, it would be 20 or 30.

What can we do about ocean acidification?

  • Reduce damaging emissions by approving policies that limit or put a price on carbon dioxide pollution.
  • Use existing laws to curb pollutants that worsen the impacts of acidification.
  • Invest in research and monitoring to determine how species will be affected, better manage fisheries, protect important habitat, and help seafood producers adapt.

Download the report, or get the snapshot in two pages.

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  1. rg says:

    Limiting more CO2 emissions will do nothing about the trillion tonnes of CO2 already emitted which represents a lethal dose of CO2 for much of ocean life.

    If we do nothing to provide the antidote to that first lethal dose then all the simplistic advice about how to not send a second lethal dose of CO2 into the environment is worse than useless, it serves to suggest the first lethal dose is toleable when it is not!

    Investing in more research when we have spent decades of research while doing nothing other than study is the same as fiddling while Rome burns, this time Rome is the ocean and it is burning in acid. It’s burning now, not at some time in the distant future. This year we may have seen the start of the extinction of the phylum mollusca.

    And as for adapting our seafood taste, there will be life in the oceans, it will simply be the cyanobacteria from which life sprung on this blue planet a billion years ago. When they finish rebooting the planetary ecosystem following our CO2 induced “blue scree of death” all will once again be able to evolve. Adapting to new seafood will be easy if you like slippery slimy smoothies, something sort of like soylent bluegreen, yum!

    Or of course one might help restore ocean green plankton which is easily able to turn our noxious CO2 from its destiny into acid death into LIFE… I for one choose life.

  2. cf says:

    I’m not an expert in ocean acidification, but I am a scientist who studies CO2 and global change. From what I know of this issue, it is more complex than the implied link between anthropogenic emissions and Pacific marine life distress. For example, a 2009 report from the Pacific Coast Shellfish Growers Association identified upwelling currents along the coast as a source of nutrients, but also a source of CO2 enriched ocean water. Deeper, colder ocean water can contain more dissolved gasses such as CO2 which can acidify water and thus harm shellfish. This CO2 is likely not from recent anthropogenic emissions, and much of the recent upwelling may be a result of climatological patterns such as ENSO and PDO. Whether these larger patterns are influenced by anthropogenic global warming is another, more tenuous story. But to state that the acidification along the Pacific coasts is entirely and simply due to anthropogenic emissions of CO2 does not appear to be correct.

  3. Jennifer Langston says:

    CF – While it’s true that recent upwelling events along the West Coast are bringing older water that was last exposed to the atmosphere decades ago (when atmospheric carbon dioxide levels were even lower), there’s plenty of evidence to support the assertion that the oceans are growing more acidic over time as a result of manmade carbon dioxide emissions. And this suggests that future upwelling events will bring even more acidified water to our shorelines. (To learn more, you could look at the work of NOAA oceanographers Richard Feely and Chris Sabine, who have developed a fingerprinting method to determine how much of the acidification we’re seeing is due to anthropogenic fossil fuel emissions.)

    You’re also right that predicting how acidification may affect any given marine species, or an entire ecosystem, is complicated, as our report points out. It’s something a number of scientists are working on in our region.

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