The phenomenon of coral bleaching

The phenomenon of coral bleaching

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CORAL WHITENING – A study conducted by the team of Terry Hughes, professor at the ARC Centre of Excellence for Coral Reef Studies at James Cook University, highlighted the occurrence of the third case of whitening of the Great Barrier Reef. But what is the phenomenon of coral bleaching and what are the causes?

The whitening of corals

Climate change is affecting our planet in many ways. Biodiversity and all the species that inhabit this Earth are at the expense and most affected at the moment. Among them are corals. In the Great Barrier Reef, off the Australian ocean, they are increasingly subject to the phenomenon of bleaching.

Corals, due to the abnormal high water temperature, release zooxanthellae, unicellular algae that live in symbiosis with corals. These algae are responsible for 90% of the energy supply needed for corals to live and are also the reason for their bright colors.

The cause of coral whitening is not only thermal shock but also increased acidity in the oceans. The phenomenon is reversible until the corals continue to have percentages of zooxanthellae. Once they’ve removed them from their system, we can never go back. The study conducted by James Cook University, however, showed that healing times are getting longer and more difficult to return to their lives.

The importance of corals

Wanting to save corals and the most famous Coral Reefs to many may seem just an act not to miss a magnificent show. There’s actually more to it than that. In fact, corals allow to safeguard marine biodiversity and constitute a natural barrier against the main atmospheric phenomena that can affect the coasts.

Without corals, coastal populations would increasingly be subject to phenomena such as tsunamis and erosion. Not to mention the economic activities associated with it.

Coral whitening buffer ideas

“We can’t make the barriers global warming-proof,” says Hughes.

However, some solutions are being sought in Australia. The list of possible ideas initially saw 160 options, of which 43 were selected. With the Great Barrier Reef they are trying one called “cloud brightening”. We are talking about spraying thousands of billions of nano crystals of sea salts into the air from a barge. Particles thrown into the air mix with low clouds and allow them to reflect more sunlight than normal. In this way we build a kind of shielding from the sun’s rays towards the water and then towards the corals and the marine species below.