We're delighted to welcome you back for another #questiongreen, as we turn our attention to the subject of carbon capture and sequestration.
With summer getting closer and closer, we've never been so close to enjoying our beautiful French beaches.
France is home to a large number of corals, particularly in its overseas territories. These corals are very important for biodiversity, and for mankind, as they provide a habitat for a large number of marine species.
Skipper and journalist Fabrice Amedeo declared that "one square kilometer of reef contains as many species as the entire French coastline". Today, the Great Barrier Reef has a surface area of 350,000 km², but there are far fewer corals than 30 years ago. As well as representing a major risk to biodiversity, it is also one less natural source of carbon sequestration to help us meet our climate targets.
Over the last 30 years, almost half of the coral on the Great Barrier Reef has disappeared. This is a tragedy for biodiversity. Coral reefs are home to almost 25% of the world's marine fauna, yet the total surface area of all these reefs represents only 0.25% of the entire marine environment. By way of comparison, the variety of flora and fauna within coral reefs is equivalent to that of the tropical forests of Amazonia or New Guinea.This biodiversity, so precious to the balance of life on Earth, is also an essential resource for mankind. Thanks to the species they support, corals provide a livelihood for almost 500 million people, including 40 million fishermen.
But if corals are dying, it's largely due to human activity and climate change. Since 1998, a phenomenon known as coral bleaching has appeared. This phenomenon is particularly intense, with very strong episodes in 2016, 2017 and 2020. Bleaching is now estimated to have reached 98% of the Great Barrier Reef.
But the loss of much of the world's coral doesn't stop there. Coral acts as both a carbon source and a carbon sink. But the net balance of the world's coral is clear: it sequesters between 68 and 88 Megatons of carbon per year, equivalent to the emissions of countries like Morocco, Israel or Greece.To take the comparison a step further, the loss of around 50% of the planet's coral would require the planting of 1.75 billion more trees each year to sequester as much carbon each year (considering that a tree captures an average of 25kgCO2e per year). This would be equivalent to adding the equivalent of 15% of the trees in France every year. So coral has more than one role to play in our future, and it's high time we took real action to preserve it, otherwise it will be increasingly difficult to reach our carbon neutrality targets, and even to survive for those parts of the world dependent on the ecosystems sheltered by coral reefs.