Underwater ‘umbrellas’ to protect Barrier Reef

The proposal, in a paper published today, also includes using low-voltage electrical currents to stimulate coral growth and defend against the worsening impact of heat stress.

The paper, in the journal Nature Climate Change, says the pace of global warming is unparalleled in 300 million years and has led to temperature rises of at least 2 degrees Celsius and a 60-per-cent increase in surface ocean acidity over the past three centuries.

Professor Ove Hoegh-Guldberg of Queensland University, Australia, writing with Greg Rau from the University of California and Elizabeth McLeod from The Nature Conservancy, calls for “unconventional, non-passive methods to conserve marine ecosystems”.

“A much broader approach to marine management and mitigation options, including shade cloth, electrical current and genetic engineering must be seriously considered,” the paper says. “The magnitude and rapidity of these changes is likely to surpass the ability of numerous marine species to adapt and survive.”

The paper proposes a range of possible future options for ocean management, including selective breeding and adding base minerals and silicates to the water to neutralise acidity.

The Barrier Reef includes about 900 coral formations stretching along 1,600 miles off Australia’s east coast. Its coral formations and marine life attract about 2 million visitors each year.

The shade cloths proposed in the report would be anchored with ropes and float on the water surface to protect the corals from sunlight. In an experiment performed in Queensland several years ago, researchers deployed 15-feet by 15-feet sheets of plastic mesh, similar to those used by gardeners to protect vegetable patches.

Professor Hoegh-Guldberg told the Daily Telegraph the technique was useful for protecting small patches of coral but would not