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Coastal Alaska is characterized by its rugged, wild landscape, remote communities and rich heritage. Families have long relied on fishing for their livelihood.  More than fifty percent of the nation's wild seafood comes from Alaska. As hunters of marine mammals, Alaskan Native peoples support traditional subsistence economies.

Alaska’s oceans sustain unparalleled fisheries and a great diversity of marine life. Corals, sponges, fish, crab, seabirds, waterfowl and marine mammals all depend on the right combination of environmental factors to flourish and each organism occupies an important niche in the marine food web. 

Today, that marine food web is threatened by ocean acidification, a condition caused by carbon dioxide in fossil fuel emissions. Since the advent of the Industrial Revolution, the oceans have been absorbing CO2 in ever-increasing quantities. It is normal for the oceans and the atmosphere to exchange carbon dioxide. For millenia, that interchange was in balance. But since humans began burning fossil fuels, the rate at which the oceans absorb the greenhouse gas has increased. Indeed, the oceans have taken up about one-third of all the CO2 emitted by human activities since the Industrial Revolution began.

In providing a convenient sink for excess CO2, the oceans help reduce the presence of the gas in the atmosphere, and thus cut its contribution to global climate change. But the tradeoff has a downside, one only recently recognized by science. The excess CO2 is changing the pH of the oceans, rendering them increasingly acidic, hence the term "ocean acidification."

As the ocean becomes more acidic, shell-making creatures large and small will find it more and more difficult to build protective shell material. Threatened are large creatures such as crab, oysters and coral, but also planktonic life forms such as pteropods that are prey for Alaska salmon, as well as other fish and sea mammal species. It has been estimated that a 10 percent drop in the population of pteropods would result in a 20-percent drop in the adult weight of pink salmon (Mathis; UAF). Conditions that threaten the health and availability of salmon also threaten the Alaska economy and the lifestyles, cultures and heritage of Alaskans.

PTEROPOD (Sea Butterfly) Photo by Russ Hopcroft, UAF School of Fisheries and Ocean Sciences.

• Ocean Acidification: The Basic Fast Facts
• An Overview of Ocean Acidification in Alaska
• Fisheries Threatened by Ocean Acidification
• Ocean Acidification Terminology
• A four-minute video on Ocean Acidification
• Prof. Jeremy Mathis, UAF, on Ocean Acidification and what it means for Alaska
• Ocean Acidification threatens Maine's seafood Industry
• Dr. Richard Feely, Ph.D., of NOAA's Pacific Marine Environmental Laboratory delivers slideshow presentation on ocean acidification