[ad_1]
LONDON (Reuters) – Researchers trying to save the Great Barrier Reef are trying to cool unusually warm sea temperatures using “cloud shine,” a geoengineering technique designed to reflect more of the sun’s rays away from Earth.
The team is spraying microscopic drops of seawater in the air over the reef, creating more cloud cover and more shade in an effort to save the health of one of the world’s most important marine ecosystems.
In the past few weeks, and for the third time in five years, the Great Barrier Reef has undergone a massive bleaching event where the stress of unusually warm water temperatures blanches white coral and can kill it.
February was the warmest month on record in terms of water temperature around the reef, with readings in places more than 3 degrees Celsius above average for the time of year.
“If we can light up the clouds a little throughout the summer, then we can cool the water enough to stop coral bleaching,” said Dr. Daniel Harrison, project leader and tenured professor at Southern Cross University.
The investigation comes after Australia suffered a devastating and protracted wildfire season that burned nearly 12 million hectares (30 million acres) of scrub, killing 33 people and approximately 1 billion native animals.
Just before the coronavirus blockade, the researchers managed to deploy two boats at a site on the Great Barrier Reef, 100 km (62 miles) west of Townsville, but without the international researchers who had planned to join them.
They tested a prototype turbine to atomize seawater and blow it into the air, with a drone in the atmosphere and a sampling container 5 kilometers (3.11 miles) away on the sea surface.
The water droplets evaporate leaving only small salt crystals that float in the atmosphere allowing the water vapor to condense around them, forming clouds.
“When we did all the analysis, the brightness of the cloud turned out to be really one of the best ideas we had found because there is very high energy leverage,” said Harrison.
“So just a small amount of energy to produce these nano-sized salt crystals results in a large amount of energy that is reflected from the cloud and cools the coral,” he added.
Next year, the team plans to test the technology at three times the size, ready for a ten-fold increase a year later, which the researchers say should be able to light up the clouds in an area of 20 by 20 kilometers.
“If we discover that this technology works as well as we hope, we might one day have these machines scattered throughout the Great Barrier Reef,” said Harrison.
“This could buy us a couple of decades, but at the same time it is absolutely essential that we reduce our emissions.”
Report by Stuart McDill; Editing by Simon Cameron-Moore
