The Great Barrier Reef’s condition was given the worst possible rating this week, as a UNESCO advisory body named climate change as its single greatest threat.
The International Union for Conservation of Nature’s (IUCN) 2020 Conservation Outlook report, which assesses the condition of World Heritage-listed natural sites, found that "a number of values" that had placed the Great Barrier Reef on the World Heritage list had deteriorated—prompting them to change its rating from "significant concern" to "critical".
Much of the damage reportedly occurred in the past four years, as the result of a number of mass bleaching events as well as the direct impacts of human behaviour and infrastructure projects.
"There has been a further dramatic decline as a result of the 2016, 2017 and 2020 coral bleaching events," the report said. "Some of the activities causing a threat to the values of the site can be influenced by the management authorities, such as fishing and coastal development.
The report further noted that "other pressures cannot be addressed at the site level, such as climate change, which is recognised as the greatest threat."
Four other Australian world heritage sites, including the Blue Mountains, the Gondwana rainforests and the Ningaloo Coast, were also found to have deteriorated. Climate change was found to be a threat to 69 percent of the country’s world heritage sites—more than double the global trend of 33 percent.
In the case of the Blue Mountains and the Gondwana rainforests, Australia’s 2019/20 “Black Summer” bushfire season was found to be the main contributing factor. Those blazes affected more than 80 percent of the Blue Mountains world heritage area and more than 50 percent of the Gondwana rainforests.
But it’s the findings in relation to the Great Barrier Reef in particular that have scientists feeling “surprised and shocked”—even though the existential threat facing the natural wonder is well-documented.
"This is a robust and scientifically rigorous report so I think it is a very grim outlook, with the key threat being climate change," Scott Heron, an Associate Professor in Physics at James Cook University, told the ABC. "Three coral-bleaching events in [less than] five years are a swaying factor in terms of the threat to the reef … however, it's not the only threat."
Dr Heron noted that inappropriate fishing, run-offs and pollution constitute other threats.
In response to the IUCN report’s findings, a spokesperson for the Australian Government’s Federal Department of Environment said that "Australia is committed to playing its role in a global response to climate change, it is investing unprecedented amounts protecting the Reef, in bushfire wildlife and habitat recovery and in supporting our world heritage places."
Nonetheless, the Australian government continues to commit to environmentally destructive energy policies and projects, Prime Minister Scott Morrison refuses to commit to a target of net zero carbon emissions by 2050, and the construction of the Adani Carmichael coal mine—which requires the dredging of over a million cubic metres of the Great Barrier Reef’s seafloor to give passage to coal ships—is underway.
Earlier this year, a report from the Australian Research Council’s Centre of Excellence for Coral Reef Studies observed that the Reef had lost more than half of its coral in the past 25 years. Andreas Dietzel, the lead author of the report, blamed human-induced climate change.
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