Environment

Turbines brighten clouds over Great Barrier Reef in world-first trial

Turbines brighten clouds over ...
The research team conducted some small-scale testing with prototype cloud-seeding equipment
The research team conducted some small-scale testing with prototype cloud-seeding equipment
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Cloud-seeding technology, which has been proposed as a way to mitigate the effects of climate change, is being tested as a way to protect the Great Barrier Reef
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Cloud-seeding technology, which has been proposed as a way to mitigate the effects of climate change, is being tested as a way to protect the Great Barrier Reef
The research team conducted some small-scale testing with prototype cloud-seeding equipment
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The research team conducted some small-scale testing with prototype cloud-seeding equipment
Microscopic sea water droplets sprayed into the air evaporate to leave behind nanoscale sea salt crystals
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Microscopic sea water droplets sprayed into the air evaporate to leave behind nanoscale sea salt crystals
The cloud-brightening trial was conducted to ascertain whether it is a way of protecting fragile corals from warming oceans
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The cloud-brightening trial was conducted to ascertain whether it is a way of protecting fragile corals from warming oceans
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Desperate times call for desperate measures, and for scientists contending with a third major bleaching event in five years at Australia’s Great Barrier Reef, such times are very much upon us. In a world first, researchers have conducted a cloud-brightening trial, to see whether reflecting some of the Sun’s energy away could help limit the damage to fragile corals caused by warming oceans.

As environmental scientists grapple with repeated, severe coral bleaching events at the Great Barrier Reef, some inventive ideas are emerging to help restore the natural wonder to full health. Coral bleaching can occur in response to irregular water temperatures that cause the organisms to expel an essential algae they rely on for nutrients and color, with the latest incident only deepening the despair.

“The Great Barrier Reef is undergoing a third mass bleaching event in just five years, and corals were bleaching all around us while we conducted our tests,” says Southern Cross University Senior Lecturer Dr Daniel Harrison. “This was both shocking and heartbreaking, in what should have been an ordinary non-El Nino non-bleaching year. It really emphasizes how little time we have for this research, reminding us of how important this work is.”

Ideas to preserve the reef for future generations in the face of rising global temperatures include using underwater robots that plant additional larvae around the ecosystem, laying protective films over the top, and raising “turbo-charged” coral babies in huge farms.

The type of cloud-seeding technology trialed by the researchers has been in the mix more broadly as a way to mitigate the effects of climate change for years. In general terms, it involves adding tiny particles to the atmosphere, which act as seeds that water vapor can cling to to become droplets and form bright, reflective clouds.

The research team, led by scientists at Sydney Institute of Marine Science and Southern Cross University, took to the waters of the reef with prototype cloud-seeding turbines to conduct some small-scale testing. These work by spraying microscopic sea water droplets into the air that evaporate to leave behind nanoscale sea salt crystals, which serve as seeds for brighter, more reflective clouds.

The cloud-brightening trial was conducted to ascertain whether it is a way of protecting fragile corals from warming oceans
The cloud-brightening trial was conducted to ascertain whether it is a way of protecting fragile corals from warming oceans

“We tested the hypothesis at one-tenth of the scale we’re aiming for, using a drone in the atmosphere and a sampling vessel 5 km (3.1 mi) away on the sea surface and showed how we can successfully create hundreds of trillion of these sea salt crystals per second which float up into the atmosphere to bolster the reflectivity of the existing clouds,” Dr Harrison said.

The team hopes to build on these results next year at three times the scale, and then 10 times the scale the following year. The researchers believe this could brighten clouds covering a 20 x 20 km (12 x 12 mi) area, but it’s not as straightforward as deploying the technology on that kind of scale. The jury is out on the safety of cloud-seeding, and how it might impact the environment in other, unforeseen ways.

As part of their research, the scientists will spend four years assessing various environmental impacts, including whether or not the technology could reshape rainfall patterns around the world. In any case, they believe the potential is clear.

“Cloud brightening could potentially protect the entire Great Barrier Reef from coral bleaching in a relatively cost-effective way, buying precious time for longer-term climate change mitigation to lower the stress on this irreplaceable ecosystem,” said Dr Harrison, who added, "in the future this technology might be able to be applied over the Great Barrier Reef to reduce the severity of coral bleaching during marine heat waves, cooling and shading the corals below.”

You can learn more about the project in the video below.

Cloud Brightening project

Source: Southern Cross University, Sydney Institute of Marine Science

View gallery - 4 images
6 comments
SteveR
How is this a good idea? Sounds like their trying to ramp up the green house effect. I can see it working with heavy cloud cover, but with light cover it'll just reflect light back to the surface.
BeinThayer
SteveR, think back today that you were outside and it was bright and sunny with only light occasional cloud cover. Most of the time the sun would be directly shining on you, but occasionally a light cloud would come between you and the sun. Do you remember when those light clouds came between you and the sun whether the temperature went up or down?
Aross
This may work during the day but has the opposite effect at night. As anyone living in a colder climate can attest to, cloudy nights are warmer than clear nights. Unless the artificial cloud cover dissipates at night the net effect is probably nil or negative.
BeinThayer
Aross, realize that cloud formation is not a product of putting signiificantly more water into the atmosphere. They are spraying sea water...not to increase humidity, but to create nucleation sights. The amount of water added is negligible. That warmth at night occurs because h2o absorbs and re-emits infrared frequencies. This occurs not only when h20 is present as a liquid but also when it is a vapor, so given the negligible amount of h20 added, there won't be a measurable heat gain from this cloud brightening. Of course, atmospheric science is not my specialty, but it is the specialty of the people who thought this iidea worthwhile enough to devote time and money to this research.
Nelson Hyde Chick
We are going to have to execute more and more herculean technologies to save the Earth just so humanity can grow and grow some more. The sad reality is that with current technology an Earth of three to four billion of us could be an Eden, at seven going on eight things are4 getting bad, fast, an Earth of nine to ten billion humans will just be one huge living Hell!
HansPro
Using the age old evolution theory about short-eared rabbits being hunted and eaten faster than long-eared rabbits hence the long-eared surviving and getting more efficient in evading attackers as time goes by. Now with this cloud thingy-majig exercise it is tantamount to interfering yonks ago by capturing and strapping plastic ears onto short-eared rabbits and then releasing them to compete artificially equally with the long-eared ones! I say, if animals or plants are incapable of adapting to environmental evolutionary changes, human industrial revolution fits into this category also, then they must die. Stop this pussyfooting of nature. Adapt or die is Mother earth’s mantra. Simples.