"Healthy Oceans, Healthy Planet" is the theme for the sixth annual day celebrating our planet's largest bodies of water. This year, more than ever, we need reminding about the crucial role the oceans play in our survival. First proposed at a UN summit in Rio de Janeiro in 1992, World Oceans Day was proclaimed officially in 2006.
Led by the Ocean Project and the World Ocean Network, communities around the world are expected to use the day to raise awareness of the problems facing the oceans, which provide a livelihood for more than 200 million people and are the main source of protein for millions more. Without healthy oceans, our planet will sicken and die. Sixteen hundred ocean conservation groups will organise beach cleanups, educational and arts events, and sustainable seafood festivals to make the point that we all rely on the oceans, and we have to preserve and protect them.
Earth is probably unique in having bodies of liquid water on the surface of our planet. Seventy-one per cent of Earth's surface is covered by water, with an average depth of about four metres. Our atmospheric temperatures and pressure are perfect for sustaining liquid water: Mars may have underground oceans, and some of Saturn's and Jupiter's moons might have them under frozen cover, but we don't know for sure.
Before the Industrial Revolution, the system whereby our oceans absorbed and released carbon dioxide and oxygen was stable, but then we started burning fossil fuels at a tremendous rate, releasing carbon dioxide into the atmosphere in life-threatening amounts. Half of that carbon was caught and held in the oceans. And now, the oceans are warming and becoming more acidic, with dangerous results for marine life. For example, the pteropod or sea butterfly is the "canary in the coal mine" for ocean acidification. It's a small shelled marine creature, found in the Arctic and southern oceans. Some scientists call it the "potato chip of the sea" because of its popularity as a food source for other animals. What makes the pteropod most significant, however, is the effect of the increasingly acid oceans on its shell: its shell is softening and disappearing. This is happening to other molluscs as well, but the pteropods are such an important part of the food chain that their disappearance would be a catastrophe. The increased acidification is a disaster for coral reefs as well: they are bleaching and dying at a truly alarming rate.
We can no longer take the oceans for granted. Yes, they are big enough to have absorbed everything we threw at them for centuries, but that time is coming to an end. We must start to show the oceans more respect, and fortunately, some people are doing that. Twenty year old Dutch inventor Boyan Slat is the CEO of The Ocean Cleanup, a huge system of booms designed to clean the ocean of floating debris without harming marine life. The "soup" of degrading plastic that is entering the food chain of every ocean on earth must be dealt with, and Slat and his colleagues hope they've found a way to eliminate some of it. A 2000-metre floating structure, the largest in the world, lying off the coast of Tsushima, an island between Japan and South Korea, will trap floating debris but allow marine life to swim below, eliminating the danger posed by nets. Eventually, the Ocean Cleanup hope to have a way to use the harvested plastic to generate energy.
With care and attention, the oceans will sustain life on Earth for centuries to come, but without that care, we'll drown in the acid, stagnant sea. Happy World Oceans Day, everybody...!