You’re unlikely to dissolve any time soon when going for a swim. And yet, the current rise in acidity of our oceans is having profound impacts on marine life, and ultimately on our lives. Find out why.
Oceans do us a great service by sucking up about a quarter of the carbon dioxide (one of our major greenhouse gases that contributes to climate change) from the atmosphere, where it forms carbon acid. For the past millions of years, this has not posed much an issue.
But as the amount of carbon has risen as a result of our consumptive lifestyles, there has been a corresponding rise of carbon absorbed into the ocean. Between 1751 and 1994, the acidity of the oceans’ surface increased by almost 30%! Now, the current rate of ocean acidification is faster than at any time in the past 300 million years.
Nemo, we have a problem
With growing amounts of carbon dioxide entering the sea, marine species are beginning to feel the pinch. Especially if they happen to wear a shell. Organisms such as crustaceans (shrimps, in all their guises and forms) and molluscs (cuttlefish for example) are in the front line--as ocean acidity drops, shells become more vulnerable to dissolution.
This not only affects the food base of other species which we are fond of, such as salmon, but also entire ecosystems such as coral reefs. In the Coral Triangle, the epicentre of marine diversity and a hot spot for the world’s coral, acidifying oceans could have dramatic results.
Reversing the trend
As incredible as it may sound, one way to address the problem is to drop some finely ground iron into the ocean. This stimulates photosynthesis in phytoplankton (microscopic organisms that wander in the sea), which helps to reduce acidity. But the amount of soluble iron dispersed into the ocean needs to be closely monitored. With too much iron, algae could bloom from the excess oxygen generated by the phytoplankton, and possibly suffocate marine life.
Ultimately, our main hope with reversing the acidity trend involves slowing down the rate at which we pump out greenhouse gases into the atmosphere. And once more, the problem is in our hands.