In a stunning revelation, Australian scientists have reported record-high coral mortality in parts of the Great Barrier Reef, raising concerns about the fate of the entire structure. The Australian Institute of Marine Science (AIMS) recently completed surveys on 12 reefs, revealing that up to 72% of corals have died. This devastating loss is attributed to a combination of factors: a severe summer of mass bleaching, two powerful cyclones, and widespread flooding.

The northern section of the reef was particularly hard-hit, with about a third of the hard coral succumbing to these extreme conditions. This marks the largest annual decline recorded in the past 39 years of government monitoring. The Great Barrier Reef, often referred to as the world's largest living structure, spans over 2, 300 kilometers and is home to a vast array of marine life. However, repeated bleaching events threaten to strip it of its vibrancy and biodiversity, turning once-thriving coral banks into ghostly white expanses.

Bleaching occurs when water temperatures rise, causing corals to expel tiny algae known as zooxanthellae. Prolonged high temperatures can lead to the coral turning white and eventually dying. This year marked the fifth mass bleaching event in eight years, with the latest survey also revealing a high death rate among acropora corals, which grow rapidly but are quick to bleach.

Lead researcher Mike Emslie described the past summer as one of the most severe periods for the reef, with heat stress levels exceeding previous records. WWF-Australia's Richard Leck expressed his grave concerns, stating that the reef's ability to recover is limited. "We are nearing a tipping point, " Leck warned, emphasizing the need for stronger emission reduction targets and a shift away from fossil fuels. He fears that the mortality rates observed in the surveyed areas may be indicative of what will be found in the full report next year.

Australia, as a major exporter of gas and coal, has recently set targets to achieve carbon neutrality. However, these latest findings underscore the urgency for more ambitious emission reduction goals, such as reaching at least 90% below 2005 levels by 2035.

The Great Barrier Reef: A Summer of Unprecedented Loss

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