Researchers at the Sydney Institute of Marine Science and the University of Sydney School of Geosciences are exploring the possibility of making low-lying clouds off the northeastern coast of Australia more reflective in order to cool the waters surrounding the Great Barrier Reef.

During the last two years, the Great Barrier Reef has been devastated by bleaching, caused by warm ocean waters. At least 20% percent of the reef died and more than 90% of it was damaged.

According to the researchers, making clouds more reflective looks like the most feasible way to protect an ecosystem that stretches across more than 335,000 square kilometres. They say that cloud brightening is the only technology that they have identified that is scalable, relatively environmentally benign and economically feasible.

A British physicist, John Latham, first proposed the idea of cloud formation as a potential way of controlling global warming nearly 30 years ago. The theory is that fleets of ships could spray tiny salt particles, generated from sea water, toward low-lying marine clouds that hug the coast. This would provide the nuclei needed to induce additional droplet formation, expanding the total surface area of the clouds.

A team of scientists in Sunnyvale, California, who have spent seven years developing a nozzle that they believe can spray salt particles of just the right size and quantity to alter the clouds, is attempting to raise several million dollars to build full-scale sprayers in order to conduct field trials.