Snow canons to save coral reefs?

The coral reefs a few hundred meters from where this picture is taken are still safe. When I read about the Australians that plan to create whiter clouds, I remember one time in Beijing in October 2009.

I was in China as an adviser to the Norwegian Red Cross Secretary General for a meeting with the China Council for Int’l Cooperation on Environment and Development. Chinese farmers had been suffering from a long period with no rain. One evening at the hotel room I heard heavy thunder. I thought.

When I woke up the next morning the streets were covered with snow. When I read the news in the afternoon it turned out that what I had heard was actually Chinese weather engineers operating weather canons shooting chemicals up in the clouds to release water. But they had done a miscalculation. What should have been rain over agriculture areas became snow over Beijing. Plains were held back and the poor engineers were heavily criticised for their mistake.

Coral reefs facing death

When Australian scientists plan to shoot salt up in the clouds to make them reflect more sunlight and slow down coral bleaching, I think about this episode.

The problem, or rather the catastrophe that is about to happen is that Great Barrier Reef is dying.

Large parts of one of Earth’s nature wonders outside Australia’s East Coast has over the past years been damaged due to increased ocean temperatures. The corals are loosing its colours, they are bleaching.

Bleaching means that corals are expelling the symbiotic algae that live in their tissues and then turn completely white. Change in ocean temperature, sunlight or changes in freshwater or pollutants. This stress can cause death to entire coral reefs. Close to one third of Great Barrier Reef was damaged in 2016-2017 according to this article in Nature. In April this year, another massive bleaching was reported.

White clouds can protect coral reefs against the sun

When clouds get whiter sunlight is reflected which in turn slows the warming of the ocean surface. The idea is that the ocean around Great Barrier Reef cools down and maybe compensates the temperature rise.

What looks like snow canons will shoot salt crystals out up in the air. These particles increase the amount of water. Critics warn that the method may affect weather systems and lead to drought and floods elsewhere. And is to decide that such clouds should be created in the first place?

The experiment that has been carried out is promising, but it will take another few years before it can be put into practice. Great Barrier Reef still needs to breath by itself for a while, but with accelerating climate change it looks a respirator will be needed in the near future.

Rescue operation for Great Barrier Reef

Great Barrier Reef is the Earth’s largest marine structure with zillions of ecosystems and tremendous biodiversity. The annual worth of the Earth’s coral reefs (ecological, economic and societal) is estimated to 9,8 trillion USD.

Australian authorities have set aside 150 millions USD to save the reef. Restoring reefs as if they are 15th century buildings so that they can stand cyclones is also being tested. Another method is to move coral larves as they produce eggs to other parts where the reef has been damaged to assist the natural coral growth.