SCIENCE BEHIND THE ART This is an artwork that beautifully illustrates a coastal environment, including coral reefs. Corals are actually classified as animals. They are formed of a multitude of tiny tentacled creatures called polyps, surrounded by an exoskeleton made of calcium carbonate. Their food comes from their symbiotic relationship with tiny algae called zooxan thellae found living in their tissues, photosynthesising and providing them with nutrients. These algae also give corals their colour. Unfortunately, corals around the world are facing multiple stressors, the most well-known one being coral bleaching. During a heatwave, the coral polyps get very stressed and subsequently expel the algae, leading to starvation and ultimately their death. After their death, only the bare white exoskeleton remains. Sometimes, corals can survive the event, but due to repeated heatwaves over the last few years, scien tists are growing increasingly concerned that many won’t recover. Another stressor is the acidification of oceans. Oceans absorb a third of manmade greenhouse gas emissions, but as carbon is dissolved in the ocean, it becomes acidic. This can then corrode corals’ calcium carbonate skeletons, stunting their growth. There is an urgent need to protect oceans and corals, which is why the UN has declared this decade the Ocean Decade, to raise awareness.
Ocean by Ariana Loehr: gouache, ink, and digital medium.
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