The GBR in black or white: coral bleaching or coal dust?

By Dave Armstrong - 24 May 2016 9:50:0 GMT
The GBR in black or white: coral bleaching or coal dust?

The GBR’s Flynn Reef displays the key diversity and colour that a major reef system (here with Acropora and many other species) brings, whether simply for tourist or for the greater needs of the ecosystem.

Flynn Reef image; Credit: © Toby Hudson/Wikimedia

Is the Great Barrier Reef threatened more by the spillage dangers from vast coal exports or from global warming or other causes of coral bleaching? Queensland is the Australian state responsible for conserving the earth’s biggest and best known coral reef. As custodians of such a feature, many would say they are not living up to their responsibility for any living organism other than company profits.

Many Asian countries receive coal exports from the giant ports such as Newcastle, located close to the GBR. Coal transport ships pass through the reef with their cargo. This means the coal dust contamination of coral has to be carefully checked, with Stephen Mearns, the Queensland Environment Minister claiming sediment and nutrient run-off are more significant coral killers. However, the experience with the MV Shen Neng 1 when it grounded near Rockhampton was extremely negative, as it does not indicate we can be confident in the Minister’s assurances about safety. With 60,000 tonnes of coal aboard and a long narrow oil slick leaking from it, it ran aground and scraped the reef for 3km in 2010. Far from sticking to shipping lanes, it was 10km outside the nearest lane.

The white threat to the GBR is of course bleaching. As oceans warm around the world because of climate change, the seas around the GBR Marne Park have increased in temperature by 2.5oCelsius, with local cloud loss contributing to that high rate of increase. As temperatures continue to rise, the GBRMPA hope that shade from cloud cover might return to reduce heat absorption. This is the Great Barrier Reef Marine Park Authority, who argue that much of the Pacific has even higher temperature rises, especially during last February and March, when El Niño was having its greatest moment!

Progress may come with the joint Australian and Queensland state governments propagating The Reef 20150 Long-Term Sustainability Plan. (Highlights here, with the doc inside)

Short term, it seems the coral is under massive thermal and pollution stress before the plan can kick in! We also considered acidification of corals on the reef this year in Mathieu Mongin and his CSIRO colleagues The exposure of the Great Barrier Reef to ocean acidification.