One tenth of one pH unit. Doesn’t sound like much, does it? What about 30 percent? That sounds a bit more significant, right? What if I told you they were the same thing?
Since the Industrial Revolution, the acidity of the world’s ocean has risen by 0.1 pH units, or 30 percent. We can’t talk about the ecosystem without talking about our involvement in it. Although some extreme activists may claim that the world would be better off if we didn’t live upon it at all, the reality is that we do exist as part of the world. The good news is that we’re equipped with will and judgment that allow us to change things we don’t like. I, for one, don’t like the evidence that’s coming out regarding this rise in acidity.
WHAT IS OCEAN ACIDIFICATION?
Ocean acidification (OA) happens when the carbon dioxide levels in the ocean are elevated. And you thought the air was the only giant part of the environment affected by our fossil fuel use! But I digress.
When carbon dioxide levels rise in ocean water, a chemical reaction drops the level of the pH in seawater. This results in a decrease of carbonate ion concentration levels and a decrease in the saturation states for calcium carbonate minerals that help shellfish and other sea life form their shells and skeletons. WOW! That was a technical mouthful, huh?
Okay, to break it down, all you need to know is that CO2 levels go up (that’s our fault) and the pH—how acidic or alkaline something is—goes down. This means that the water is more acidic. More acidity means fewer carbonate ions, a building block for shells, which means softer shells for lobsters.
WHAT ARE THE EFFECTS OF OA?
You’re smart; otherwise you wouldn’t be a regular reader of our site. So you don’t really need me to tell you that softer shells are bad for lobsters, shrimp and oysters. However, what you might not realize—because I didn’t think about it at first—is that higher levels of CO2 means that oysters, clams, plankton, sea urchins and coral are all at risk.
HOW SERIOUS IS THIS, REALLY?
Oh, the grey area again! We can’t really tell how serious this is. Will it stay static at the current acidity level, allowing current species to evolve? Will it skyrocket over the next 100 years? The truth is, ocean acidification is an emerging problem. Judging from projected acidity levels for the year 2100, certain species of shellfish will dissolve—literally dissolve—within 45 days of life. And it seems that this sort of thing is already happening. Taylor Shellfish Farms, a fifth-generation farm in Oregon has stated that its baby oysters cannot even reach maturation because the ocean water is dissolving their protective shells. Quite simply, we don’t know where we’re headed with OA yet, but it’s time to start paying attention.
WHY SHOULD I CARE?
Quite simply, ocean acidification is our doing. The same fossil fuel emissions that have harmed the atmosphere are harming the oceans. Sure, you may not run a shellfish farm in the Pacific Northwest, but the activities we participate in affect those shellfish farms. According to the United Nations Environment Program (UNEP), ocean acidification has the potential for altering biodiversity, species composition, tourism, fishing industries and the entire food web.
Over one billion people around the world depend on food from the ocean as their primary source of protein. OA could spell disaster for these populations because if the fish they eat don’t have crunchy little shellfish to eat first, there won’t be any fish. Plus, there’s the economic impact that must be considered: fewer fish that can be caught in the wild result in fewer fishermen who are able to earn their living on the ocean.
Any move to adopt eco-friendly practices by individuals and companies is a move in the right direction as far as the oceans are concerned.
ICES Journal of Marine Science