by Hannah Heimbuch featured in the Arctic Sounder, the Homer Tribune, and the Alaska Dispatch News
Our planet is a place of ongoing evolution, with ecosystems under constant shift as we adapt in relationship to one another and to the global climate that sustains us.
So how do we put the realities of ocean acidification into perspective? How do we describe a fundamental change in the chemistry of the water covering more than 70 percent of Earth’s surface?
National Oceanic and Atmospheric Administration’s Shallin Busch put it this way at a recent Anchorage workshop on ocean acidification: the last time the ocean was at the pH levels we’re currently seeing, Earth was experiencing the dawn of horses. It’s been eons.
And current levels are not the result of a gradual peak and valley shift over the last million years. The present rate of change is 100 times greater than any rate in the last 20 million years. Acidification is a fast-paced reality, the likes of which have not been seen during the human era.
While the issue is complex, Busch said, the chemistry is relatively simple. The ocean absorbs and dissolves about one third of atmospheric carbon dioxide, which has risen exponentially in the industrial age. If it’s in the air, it’s in the water. And when it dissolves, it creates carbonic acid.
By the year 2100, ocean acidity on the present trajectory could increase 100 to 150 percent, Busch said, a massive number when we’re considering the sensitivity of marine life to water chemistry. Life can adapt, yes, but can it adapt that fast? Is the marine ecosystem able to withstand fast and sweeping changes to climate?
These are essential questions, and the field is young; scientists have been conducting major ocean acidification research for less than a decade.
Recent studies have identified a number of areas where acidification is already having a direct impact.
Pteropods are pea-sized creatures consumed by a huge variety of marine life — including fish, krill, birds and whales. Their calcium shells are thin and sensitive to changes in environmental chemistry, causing them to break down in acidic conditions, and making it difficult for them to build the shell structure at all. This is true for other shellfish species, including those essential to the North Pacific shellfish industries that create thousands of coastal jobs.
Another study has shown that higher acidity has impacted the neurotransmitters of clown fish, affecting their development and behavior.
Studies of red king crab collected in Bristol Bay show decreased survival and growth of embryos and larvae exposed to acidic conditions. According to Bob Foy and Tom Hurst’s presentation at the Anchorage workshop, continuation of this trajectory would result in closure of the crab fishery by the year 2100.
These are just a few of the isolated incidents where acidification has been linked to biological change in sea creatures.
Even for marine species not directly affected by this shift of chemistry, changes to the predator-prey dynamic or to prey survival rate is likely or guaranteed to affect them in some way. The reason we talk about ecosystems, about food webs, is because changes to individuals mean changes to the whole. When we talk about pteropods, and clown fish, and red king crab, it’s a big deal for everyone under the ocean, and everyone on the surface that relies on a healthy marine environment.
Levels of acidification vary across the globe, and its impact varies from species to species. But one thing is clear: we need to know more. This is the message to remember when it comes time to making hard choices about budgeting — whether you are choosing to support a research organization or legislation that funds that research.
Alaska and Washington have had some successes in securing funding for monitoring and researching acidification levels and effects in recent years, but it’s time to reestablish that support, and it’s far from a sure thing.
In the coming legislative session there will be intense discussion about what we can and cannot afford. As a state and a nation we face funding challenges that will put pressure on existing programs.
I urge you to make our ocean climate a priority — for you and for the leaders you have sent to Juneau and Washington, D.C.
Alaska cannot afford to take a follower position in this effort. We must be a leader in research and education, and in our dedication to understanding and mitigating the long-term effects of ocean acidification on our local, regional and global ecology.
Naturally occurring carbon dioxide is particularly rich in deep ocean environments, making coastal upwelling zones like the Pacific Northwest — where nutrient-rich water comes up from those deeper levels — particularly vulnerable to rising acidity.
Recent research has shown the Bering Sea to be home to the world’s most acidic seawater.
It is imperative that we meet our increased vulnerability with increased concern.
Organizations around Alaska are working hard to support the research, public outreach, technology and funding absolutely essential to tracking and mitigating the effects of ocean acidification. The Alaska Marine Conservation Council, Cook Inletkeeper, Alaska Sea Grant, Alaska Center for Climate Assessment and Policy, the Alaska Ocean Observing System, the UAF Ocean Acidification Research Center and NOAA are just some of the organizations and agencies engaged in that important work.
At the beginning of the Anchorage OA workshop, Global Ocean Health director Brad Warren described a conversation he had a few years ago with author Elizabeth Kolbert, whose essay in a 2006 New Yorker focused on acidification.
She asked him what he was doing about it. He said, nothing. There’s nothing you can do.
Given the scope and complexity of our oceans, the saturation of carbon dioxide in our atmosphere and our current dependence on the mechanisms that continue to release it, it would be easy to assume there’s nothing that can be done. Kolbert gave Warren a different message.
“She said, ‘You’re wrong. Get busy.’ ”
He did, others have, but more effort is needed. This issue deserves the support of a concerned Alaska public, willing to push for understanding of a change that affects us all.
Lifelong Alaskan Hannah Heimbuch is the Alaska Marine Conservation Council’s community fisheries organizer, based in Homer. She is also a Gulf of Alaska commercial salmon and halibut fisherman.
Comments