What is Ocean Acidification?

Oceans have always remained an integral part of our planet. For millions of years, oceans have maintained their acidity levels to ensure ecosystem underwater flourished. But this is now changing. Oceans are now slowly turning acidic because they are absorbing the carbon dioxide (CO₂) that we humans are pumping into the environment – to the tune of 22 million tons a day!

What is ocean acidification?

Ocean waters are typically basic on a pH scale that runs from 0 to 14. Oceans have maintained a pH level of 8.2 for tens of millions of years. But due to the enormous amounts of CO₂ present in the environment and the fact that they absorb about 30% of atmospheric CO₂, oceans are turning acidic. A recent study has found that the pH levels have now shifted from 8.2 to 8.1. Since the pH scale is logarithmic, a 0.1-point change is equivalent to about 26% increase in acidity.

What is causing this drastic change?

We know that CO₂ is the culprit but is it? Since the beginning of the Industrial Revolution, we have completely shifted gears in terms of developing and polluting. We became heavily dependent on fossil fuels, so much that we now find it difficult to move to cleaner alternatives. Burning of fossil fuels emits CO₂ in the atmosphere…billions of tons since this all began. This altered the ocean pH although left us with slightly lower levels of CO₂.

What are the consequences?

More CO₂ in oceans means more carbonic acid. This means lower levels of calcium carbonate mineral which is otherwise present in abundance and is the building block of many sea organisms. Higher CO₂ concentration in seawater inhibits shell growth in organisms like deep water corals, sea urchins, oysters, and planktons. It also disrupts the reproductive cycle in many organisms.

What’s more? As oceans continue their process of absorbing CO₂, they are likely to become saturated. Oversaturated oceans can spell disaster as that will leave us with more CO₂ in the environment to tackle. Maybe more than we can handle, aggravating climate change.

Ocean acidification is an emerging field of research and more insights are awaited. However, we must do our bit to decrease our carbon footprint irrespective of how small the effort is.