Great Barrier Reef Faces Catastrophe
Scientists fear that this year the Great Barrier Reef is undergoing another bleaching - this would be the first time that the world's largest barrier reef has suffered back-to-back bleaching. And is comes as news that last year's event had a catastrophic mortality rate on the corals affected - as high as 83 per cent in some areas.
'We didn’t expect to see this level of destruction to the Great Barrier Reef for another 30 years,' said Terry Hughes, director of a government-funded centre for coral reef studies at James Cook University in Australia and the lead author of a paper on the reef that is being published today as the cover article of the journal Nature. 'In the north, I saw hundreds of reefs — literally two-thirds of the reefs were dying and are now dead.'
Surveys held at this time last year revealed that the GBR has suffered its worst bleaching event in recorded history. Around areas such as Lizard Island water temperatures were reaching 33ºC in the shallows in March. The northern section of the reef was particularly badly hit with bleaching on 90 per cent of reefs and with reported mortality rates of more than 50 per cent. Overall it was reported that 22 per cent of the coral making up the GBR was killed by last year's bleaching
However, the report in Nature establishes the 'severity of the 2016 bleaching was off the chart' and that the bleachings events of 1998, 2002 and 2016 combined had damaged 91per cent of the coral making up the reef. These events had been triggered by the warming impact of the sporadic El Nino weather pattern. However, today's report says that global climate change is now pushing ocean temperatures to such a point that the destruction of coral reefs could become common.
Early reports suggest that water temperatures are again beyond the point which can sustain healthy coral life (roughly 29.5ºC) along vast swathes of the northern section of the reef.
Hughes, who is launching a major survey of this year's impacts today, said he hoped coming weeks would 'cool off quickly and this year’s bleaching won’t be anything like last year'.
'It broke my heart to see so many corals dying on northern reefs on the Great Barrier Reef in 2016,' Hughes said.
'With rising temperatures due to global warming, it’s only a matter of time before we see more of these events. A fourth event after only one year would be a major blow to the reef.'