It’s a story we’ve all heard a hundred times before: carbon dioxide levels are skyrocketing, it’s because of us, and this is responsible for many of the patterns of climate change that we have been seeing recently around the globe. As far as many people are concerned, the story stops there.
In reality, global warming is only part of the problem. What if I told you that half of all carbon emissions produced by humans actually end up dissolved in the ocean? This is (sort of) good news for us, since it means that we won’t feel the full effects of global warming right away.
But this is definitely not good news for fishes and other marine critters. In a process aptly named “ocean acidification”, carbon dioxide dissolves in the ocean and produces an acid (click here for a more technical explanation of ocean acidification). The result? Our oceans are becoming acidic, and fast. This is a major issue, as acidic conditions cause sharks to swim strangely and stunt the growth of pink salmon. Ocean acidification can also affect brain chemistry by causing clownfish to swim towards, rather than away from, predators. The effects of ocean acidification are so worrisome that even some fish are showing signs of anxiety about what is going to happen to them!
And that isn’t even the worst part. Marine organisms such as oysters and snails are among the most severely affected by ocean acidification, as a result of a chemical reaction between the calcium carbonate in their shells and the acid in ocean water. What ends up happening to their shells is the same as what happens to the (calcium carbonate!) shell of a chicken egg immersed in an acid for too long: it melts. The only reason why we don’t see any shellfish wandering around without their shells is because these organisms continually invest energy in the hopes of maintaining their calcium carbonate homes. But, like any investment in a drowning company, it’s a lose-lose situation no matter what strategy they use. If they do nothing, their shells will become thin and weak, and be useless for defense against hungry predators. But if they do invest in their shells, this will leave less energy available for things like growth or reproduction.
So what are our poor shellfish to do? Unfortunately, there isn’t much that they can do. Instead, their future depends entirely on the decisions we make. Luckily, individuals like you and I can make a massive difference! All we have to do is simply to recognize the problem, and commit to change. Every little thing matters! And so, the next time you turn off lights you aren’t using, take public transportation, or compost your coffee cup (or even better, use a reusable one!), just think: you’re changing the world for the better. One tiny life at a time.