Why you should care about the oceans
The oceans. They cover more than 70% of the surface of our planet. Although we have been exploring the oceans for centuries, there is still much we don’t know. But we do know is that on average, oceans have a depth of 3.7 kilometre. The maximum depth is found in the Challenger Deep, located in the western Pacific Ocean: estimated at 11 kilometre . So, now imagine how deep this is in comparison to the Mount Everest of 8.8-kilometre height!
There are plenty of reasons to love the oceans: they provide us with food, medicines and jobs. Also, ocean currents transport heat around the globe . And many people enjoy the beauty of the oceans, such as coral reefs. But there is another reason for us to appreciate the oceans: they let us breathe!
Oxygen from oceans?
The oceans are responsible for providing at least 50%-80% of all oxygen on this planet [2,3]. Seriously?! That’s not just the Amazon rainforest? Yes indeed! It is known to many that trees and plants produce oxygen through a process called photosynthesis. But also the oceans host many little plant creatures, called phytoplankton .
Phytoplankton are bacteria or one-cell plants and can’t be seen without the help of a microscope. These tiny cells flow with the ocean currents. Sometimes, ocean currents can lead to a dense collection of nutrients, which helps the phytoplankton to grow . And then the most magical thing happens: they can be seen from space! This spectacular show might be responsible for the next breath you’ll take. This picture shows an algal bloom at the coast of Iceland.
If you’re not convinced yet that our oceans are awesome, here is another reason to love them: a lot of the CO2 that we emitted as humans has been absorbed by the oceans . Furthermore, oceans support blue carbon. Blue carbon stands for all the carbon that is stored in ecosystems in the oceans, such as mangroves or sea grasses . Just as plants take CO2 from the atmosphere, these (water)plants take CO2 from the water. They can store faster and longer than most plants on land. And this makes them very important in fighting climate change .
However, the oceans are threatened. We already wrote about plastics in the ocean, which kills marine life. But there are more threats. As CO2 dissolves into the oceans, the water becomes more acidic through a process called ocean acidification . If you’re into chemistry, you know about acid–base reactions. A substance with a low pH reacts with a substance with a high pH. For example, try adding vinegar to baking soda. See how it creates bubbles? If acidic water gets in touch with shells and skeletons, we see the same response . In this figure you see how the shell of a pteropod (some kind of sea snail) dissolves as CO2 concentrations increase.
Photo by David Liittschwager
Another issue is that the oceans get warmer, just like the atmosphere. All the extra CO2 in the atmosphere traps heat, through the greenhouse effect. About 90% of that extra heat has been transported to the oceans over the past decades . This means that it’s getting a lot warmer. When we experience a very warm day, we can often cool down by taking a swim or hiding in the shade. But marine animals can’t do that. Ocean heatwaves can cause that much stress, that corals start bleaching . Some fish migrate to cooler waters . We also experience changing weather patterns and increasing sea levels .
The issues are known, action is urgent. If we don’t take care of our oceans, they might not be able to take care of us. They are more than a source of money, a way of transport, or an inspiration. We need the oceans, now it’s time to give the oceans what they need: a voice.
We think this message is important. Our oceans are vulnerable and many species are at the edge of extinction. Making people aware is a first step to get to solutions. Therefore we ask you to spread this article with your friends and family. Make them aware, give the oceans a voice. Thank you!
– If you’re a seafood consumer, try to eat less of it. Many marine animals are threatened. If you do buy seafood, look for a certification and traceability of the product.
– If you live close to the oceans or you like to visit: ask around about local problems. Being aware is a first step. Maybe you can help around, for example with beach clean-ups or spreading information.