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- Massive bleaching of the coral on the northern end of the Great Barrier Reef
Massive bleaching of the coral on the northern end of the Great Barrier Reef
Australia
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6 months agoProblems
Causes of massive bleaching of the coral on the northern end of the Great Barrier Reef
The Great Barrier Reef is the world's largest coral reef system composed of over 2,900 individual reefs and 900 islands stretching for over 2,300 kilometres (1,400 mi) over an area of approximately 344,400 square kilometres (133,000 sq mi). The reef is located in the Coral Sea, off the coast of Queensland, Australia, separated from the coast by a channel 100 miles wide in places and over 200 feet deep. The Great Barrier Reef can be seen from outer space and is the world's biggest single structure made by living organisms. This reef structure is composed of and built by billions of tiny organisms, known as coral polyps. It supports a wide diversity of life, including many vulnerable or endangered species, some of which may be endemic to the reef system. Thirty species of cetaceans have been recorded in the Great Barrier Reef, including the dwarf minke whale, Indo-Pacific humpback dolphin, and the humpback whale. Large populations of dugongs live there. More than 1,500 fish species live on the reef, including the clownfish, red bass, red-throat emperor, and several species of snapper and coral trout. According to study by the National Academy of Sciences the Great Barrier Reef has lost more than half of its corals. Causes of coral death at the northern tip of the Great Barrier Reef: ● climate change ● pollution ● shipping accidents, oil spills ● tropical cyclones. The Great Barrier Reef Marine Park Authority considers the greatest threat to the Great Barrier Reef to be climate change, causing ocean warming which increases coral bleaching. As global warming continues, corals will not be able to keep up with increasing ocean temperatures. Coral bleaching events lead to increased disease susceptibility, which causes detrimental ecological effects for reef communities. Bleaching events in benthic coral communities (deeper than 20 metres or 66 feet) in the Great Barrier reef are not as well documented as those at shallower depths, but recent research has shown that benthic communities are just as negatively impacted in the face of rising ocean temperatures. Five Great Barrier Reef species of large benthic corals were found bleached under elevated temperatures, affirming that benthic corals are vulnerable to thermal stress. Bleaching occurs when under-stress corals expel the algae living within them that gives them color and life. They can recover but only if conditions allow it.
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2026
February 19
The Australian Conservation Foundation has written to the Minister with a ‘reconsideration request’ based on substantial new information in the scientific report, which finds that the burning of gas from Woodside’s proposed Browse offshore gas field would result in the death of an additional 29.35 million individual coral colonies in every mass bleaching event on the Great Barrier Reef. Using peer-reviewed methodology that allows for ‘end-to-end’ project-specific attribution, Professor Sarah Perkins-Kirkpatrick, a coordinating lead author of the IPCC’s 7th assessment report on the physical scientific basis for climate change, has assessed the consequences for the Great Barrier Reef from the 1.6 billion tonnes of climate pollution that would be produced from Woodside’s proposed gas project. Professor Perkins-Kirkpatrick finds that the burning of gas from the Browse project alone will result in the death of approximately 29.35 million individual coral colonies in every mass bleaching event on the Great Barrier Reef. “This scientific report presents substantial new information about the damage that will be caused if Woodside exploits the Browse gas,” said ACF CEO Adam Bandt. “We believe Minister Watt should widen his assessment of Woodside’s Browse proposal to take account of the project’s impact on the Great Barrier Reef – a World Heritage site and ‘matter of national environmental significance.’ “Exported coal and gas come back to Australia as heatwaves, bushfires, floods and coral bleaching. There is no excuse for new or expanded coal or gas projects.” Woodside plans to pipe the gas from Browse to the controversial North West Shelf gas hub for processing.
2024
Parts of Australia’s iconic Great Barrier Reef, famed for its stunning colors and biodiversity, suffered the biggest decline of coral on record after a marine heatwave bleached vast swathes of hard coral, a report has found. The reef had its worst summer on record in 2024 when the world underwent a rare global mass coral bleaching event, impacting dozens of countries. Surging water temperatures combined with an El Niño weather pattern caused stressed corals to expel algae and lose their color. An official analysis now shows the reef lost between a quarter and a third of its hard coral cover across three main regions, according to the Australian Institute of Marine Science (AIMS). In some areas, particularly hard-hit reefs lost up to 70% of their living coral. The 2024 bleaching event “had the largest spatial footprint ever recorded on the (Great Barrier Reef),” the report found. “The declines in the north and south were the largest in a single year since monitoring began 39 years ago.” The massive loss across the 2,300-kilometer (1,400-mile) ecosystem is especially discouraging after it experienced significant growth in the last few years, with some fast-growing corals that helped the reef recover from previous bleaching. “The coral reefs of the future are unlikely to look like those of the past. The loss of biodiversity seems inevitable,” the report read, urging more research into reef adaptation and protection while the world works to reduce greenhouse gas emissions.
2022
March
Water temperatures spiked and stayed high for several weeks, creating marine heatwave conditions. Many areas were more than 2°C (3.6°F) warmer than normal. Bleaching affected both inshore and offshore reefs in all four management areas (the Far Northern, Cairns–Cooktown, Townsville–Whitsunday, and Mackay–Capricorn), but was most severe in the northern and central sections. After conducting aerial surveys of more than 750 reefs in the marine park, the Australian government’s Great Barrier Reef Marine Park Authority confirmed that a mass bleaching event had occurred. It is sixth widespread bleaching event of the Great Barrier Reef.
2020
Fifth mass bleaching of the Great Barrier Reef. But there was very low coral mortality.
2017
Fourth mass bleaching of the Great Barrier Reef.
2016
Third mass bleaching of the Great Barrier Reef.
2007
Australian World Heritage places included The Great Barrier Reef in its list.
2006
The Queensland National Trust named the Great Barrier Reef a state icon of Queensland.
2002
Second mass bleaching of the Great Barrier Reef.
1998
First widespread bleaching event of the Great Barrier Reef.
1997
CNN labelled the Great Barrier Reef one of the seven natural wonders of the world.
1981
The Great Barrier Reef selected as a World Heritage Site.
