SYDNEY • Australian scientists managing the Great Barrier Reef have lifted their emergency response to the highest level following the publication of video footage of damage caused by coral bleaching.
Environmental groups are urging greater action on climate change after the Great Barrier Reef Marine Park Authority said recent underwater surveys had detected "substantial levels of coral mortality" in the remote far north areas, blaming prolonged higher-than-average sea surface temperatures.
New video footage shot by the University of Queensland's CoralWatch group has raised serious concerns among scientists and environmental groups about the growing impact of climate change. "The new video and stills are very concerning and show large sections of coral drained of all colour and fighting for survival," World Wide Fund for Nature (WWF) spokesman Richard Leck said.
"This is the worst coral bleaching event ever to hit this most pristine part of the Great Barrier Reef."
The authorities said that areas of the World Heritage site were experiencing the worst bleaching in 15 years, at least partially as a result of the current El Nino, one of the strongest in two decades. Scientists said the reef needs a break in El Nino conditions within weeks if some coral areas are to survive, but the Australian Bureau of Meteorology recently forecast a continuation of El Nino conditions.
Environment Minister Greg Hunt, who inspected the area by air on Sunday, said yesterday that despite periodic El Ninos, overlaying such events with climate change "does exacerbate them". "And that's why the Paris outcome... is fundamental," he told ABC News, referring to the global deal last year aimed at curbing carbon emissions and limiting warming.
Coral bleaching is a process by which coral expels living algae, causing it to calcify. Coral can survive only within a narrow band of ocean temperature.
Last year was the hottest on record and 2016 could be even hotter due to El Nino, the World Meteorological Organisation has said.
The Great Barrier Reef stretches 2,000km along Australia's north- east coast and is the world's largest living ecosystem. It brings in billions of dollars a year in tourism revenue.
Unesco's World Heritage Committee last May stopped short of placing the Great Barrier Reef on an "in danger" list, but the ruling raised long-term concerns about its future.
"The reef can recover but we must speed up the shift to clean, renewable energy and we must build reef resilience by reducing runoff pollution from farms and land clearing," said WWF's Mr Leck.
Greenpeace Australia Pacific's Shani Tager called on the government to reconsider coal mining, saying the burning of the fuel was "driving climate change, warming our waters and bleaching the life and colour out of our reef".
REUTERS, AGENCE FRANCE-PRESSE