In Australia, the UN at the bedside of the Great Barrier Reef again threatened with bleaching

This inspection will last about ten days with numerous rotations by helicopter and plane above this sumptuous and gigantic reef, 2,300 km long. The objective is to assess, at the end of the austral summer, the extent of this new episode of coral bleaching. The conclusions will then be forwarded to the World Heritage Commission. Next June, it could then classify the Great Barrier Reef as a “site in danger”. This is what the Australian government, very climatosceptic, seeks to avoid absolutely because it would be a political failure with economic consequences: a potential impact on tourism, a major resource in the province of Queensland, in the northeast of the country.

Last year, Australia avoided this classification, by announcing a massive plan of several billion dollars to fight against the degradation of the Great Barrier Reef. But this plan only tackles the consequences, not the causes, namely the gas emissions at the origin of global warming. And the Australian economy continues to favor fossil fuels, coal in particular.

There is no doubt about this new episode of coral bleaching: the images shot on the reef speak for themselves. In the area off the town of Townsville in particular, over a strip 250 km long, the bleaching is obvious.

It is a very particular algae, nicknamed Zooks, which colors the coral. When the temperature rises too much, the algae produce a toxin, which is then rejected by the coral, which loses its color and withers. Before potentially breaking. And the coral serves as shelter for many species, fish or molluscs. The Great Barrier has 1,600 species of fish and 3,000 of molluscs. In recent months, throughout the region, the water temperature has greatly exceeded the average: between half a degree and 3 degrees depending on the moment. It is prohibitive. Scientists fear that the area affected by the bleaching is much larger than just the area of ​​Townsville. This is also what this UN mission will seek to establish.

Most concerning; is the increasing frequency of these bleaching episodes: it is the 6th in 25 years, and the 4th in six years, after 2016, 2017 and 2020. However this year, the region was affected by the meteorological phenomenon of La Nina which usually brings rain, clouds and milder temperatures. But that wasn’t enough. For the coral to regenerate and regain its colors, the temperature must drop long enough for the algae to return. If bleaching starts to occur every year or two, destruction of coral will be without return.

Australian scientists are also beginning to say that they don’t even have the appropriate modeling system: too many uncertainties and too rapid an evolution. Recall that at the beginning of March, the new report by IPCC scientists, which went relatively unnoticed due to the war in Ukraine, highlighted a rapid deterioration in the situation, stressing that global warming is already affecting half of the world’s population.


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