The Great Barrier Reef's beautiful coral reefs are being lost in a way that will never return

The Great Barrier Reef is the world's largest coral reef area, stretching off the northeast coast of the Australian continent, and is registered as a World Heritage Site . According to a survey report issued every five years by the Great Barrier Reef Marine Park Authority , the Great Barrier Reef is deteriorating primarily due to climate change, and there is a possibility that the beautiful coral reef may be lost in an irreversible manner.

Outlook Report 2024 | gbrmpa
https://www2.gbrmpa.gov.au/our-work/outlook-report-2024

'Humanity is failing': official report warns our chance to save the Great Barrier Reef is fast closing
https://theconversation.com/humanity-is-failing-official-report-warns-our-chance-to-save-the-great-barrier-reef-is-fast-closing-237441

When corals become stressed due to seawater temperatures that are too high or too low, or a decrease in the salinity of the ocean caused by the inflow of fresh water, they lose the 'symbiotic algae' that live inside their bodies. Corals that have lost their symbiotic algae will continue to live for a while even though they will lose color and turn completely white , but they will eventually die because they can no longer receive the products of photosynthesis that the symbiotic algae produced through photosynthesis. An aerial survey of the Great Barrier Reef found that as of 2016, 93% of the total area was affected by bleaching.

Coral bleaching is spreading around the world, with some experts saying it's 'irreversible' - GIGAZINE

The Outlook Report, published by the Great Barrier Reef Marine Park Authority every five years, reports the results of an investigation into the health and future sustainability of the Great Barrier Reef. The report, released on August 23, 2024, shows that the Great Barrier Reef is still facing a global coral reef crisis, with the main causes cited as direct damage caused by humans, such as climate change, coastal development, and illegal fishing.

The Outlook report notes that the condition of some coral species has improved from 'very poor' to 'poor' over the past five years, but Professor Ove Hoog-Guldberg from the University of Queensland's School of Environment warns that this only means that fast-growing coral species are recovering, and that overall the situation is still 'dire'.

Gurdberg also noted that the 2024 Outlook Report covers a five-year period ending in December 2023. From December to February in Australia, it is summer, and in 2024, the sea surface temperature rose due to the record heat wave, and a large-scale bleaching phenomenon was confirmed. The image below is the result of a survey reported in June 2024 by marine ecology researchers from several Australian universities, with the image on the left taken in March 2024 and the image on the right taken in June 2024. You can compare them by moving the slider. You can see that almost all the corals in the same place have died in just three months.

According to the Outlook report, the deterioration of coral reefs is likely due to rising water temperatures caused by climate change, as well as marine pollution, sediment runoff, and the proliferation of crown-of-thorns starfish , which feed on coral reefs.

'Coral reefs are suffering severe damage, and even slight increases in global warming will make the damage worse. Humanity must take urgent action to limit global temperature rise. But as things stand, we are failing and we continue to lose the Great Barrier Reef, and coral reefs across the planet. There was a time when governments and reef managers were unwilling to acknowledge the seriousness of the problem, but I don't think that's the case anymore. Climate change is a global issue and we need strong political leadership to address it,' said Guldberg, pointing out the seriousness of the problem and the need for a stance toward improving it.