BENEATH THE SURFACE
– Agnes V Philip
TY BSc
Reading time: 5 mins
Heard about climate’s evil twin? How evil can this be? Is it more dangerous than perilous climate change itself? While climate change has the potential to alter the seasons, cause floods, droughts, landslides, and forest fires, snatch the frozen snow and melt it, and endanger many living creatures, how aggressive will its twin be? Will its effect be more than that of climate change?
I am talking about the infamous ocean acidification, the evil twin of climate change. So, how does ocean acidification affect marine life? Are the marine creatures the only ones being affected or are we also going to be affected?
In simple words, ocean acidification occurs when seawater becomes more acidic because of the excess carbon dioxide it absorbs from the atmosphere. Ocean is known as the planet’s largest carbon sink, it generates 50 percent of the oxygen we need, absorbs 25 percent of all carbon dioxide emissions, and captures 90 percent of the excess heat generated by these emissions. It takes 20 times more carbon dioxide emissions than trees.
But little did she know that aiding the atmosphere would come at the cost of her marine creatures. When oceans absorb carbon dioxide, a chemical reaction occurs that reduces the seawater pH levels and the saturation states of biologically important calcium carbonate. Calcium carbonate plays a vital role in the building of shells and skeletons of many marine organisms. With the increase in acidity, the growth of calcium carbonate structures, under severe acidification, can dissolve faster than they can be formed.
Ocean today, on average, is 25% more acidic than it was during pre-industrial times. It is acidifying faster than ever before. Increased acidity poses a significant threat to coral reefs causing them to dissolve. Already 50 percent of the Coral Reefs have been destroyed. Coral reefs may cover less than one percent of the seafloor but are home to millions of species including fish, turtles, crabs, starfish, lobsters, seahorses, and more. They are the most diverse natural community on the planet. Coral reefs provide crucial habitat for marine creatures, protect coastlines from storms, and are food and resources for millions of people. Scientists predict that if current trends continue, the world’s coral could be wiped out by mid-century.
The effects of ocean acidification go beyond corals, they affect plankton. Despite their tiny size, plankton are powerful organisms. Half of the photosynthesis on Earth is due to plankton. They form the base of the marine food chain, and even corals feed on these plankton. They provide food for many marine animals, from small fish to large whales. Plankton also produce oxygen, accounting for two out of every three breaths we take. 40% of the plankton has fallen since 1950 due to the combined effect of ocean warming and acidification. We are losing them at the rate of one percent every year.
Human health and the economy are also under threat from ocean acidification. The ocean provides essential resources for human well–being, including oxygen, food, livelihood, and more. Of the global population of 7.8 billion, more than 4.5 billion obtain at least 15% of their animal protein from fish. Ocean acidification negatively impacts the survival, growth, development, and reproduction of marine species. Additionally, many harmful algae species produce more toxins and proliferate more rapidly in acidified waters. This can lead to contamination of fish and marine mammals posing a risk to human health and affecting the economy.
Nature always seems to adapt to changes so what’s the problem you may ask? The issue lies in the time lag between the emission of carbon dioxide and its absorption by the ocean. Even if the carbon dioxide emission went to zero today, it might take 20- 30 years to equalize with the ocean. To make this possible we not only have to cut emissions but pull carbon out of the atmosphere before it is absorbed by oceans.
Oceans are dying, reefs are suffering, which means 70% of the planet is in decline and we are aware of the harm that has been done to the atmosphere. Essentially, our “Mother” Earth is becoming exhausted. Do we value her enough to want her to be in her original, beautiful form? Has it been too late for us to envision ourselves in a world that has no climatic problems? A world with fewer disasters because of our actions? Well, I think the cost of doing nothing is enormous. So, let’s take responsibility and do what is possible with our own two hands rather than waiting for someone else to begin and make a difference.