The Tweet: “Scientists are considering whitening the clouds to combat global warming.”

Researchers are revisiting a proposal to turn sea water into clouds in an attempt to combat climate change. Ships could be remotely controlled and wind powered, roaming the oceans casting sea salt particles into the air in a project called marine cloud brightening.

Clouds form when water droplets collect around particles in the air. The smaller the droplets, the whiter the appearance of the clouds, as light refracts more through the droplets. In the case of marine cloud brightening, sea salt particles could be used to seed clouds over the oceans. The researchers behind the renewed interest in the project added; “It turns out that a greater number of smaller drops has a greater surface area, so it means the clouds reflect a greater amount of light back into space.” By geoengineering white clouds in this way, scientists hope to find a way to reflect more of the Sun’s radiation away from Earth. Whiter clouds are more reflective so would make a more effective solution.

Atmospheric physicist Rob Wood from the University of Washington put forward an idea for how such a project could be tested in a paper published in the Philosophical Transactions of the Royal Society. At this stage, marine cloud brightening is just theoretical but Wood hopes that his paper will encourage scientists to make it reality: “What we’re trying to do is make the case that this is a beneficial experiment to do. I would rather that responsible scientists test the idea than groups that might have a vested interest in proving its success,” added Wood.

The groups with a ‘vested interest’ are large geoengineering firms who might monetise the project, and this worries many campaigners who think the projects like this shouldn’t go ahead until the field is regulated.

Wood says the technique would only offer a short term solution to climate change; “It’s a quick-fix idea when really what we need to do is move toward a low-carbon emission economy, which is turning out to be a long process.”

“We stress that there would be no justification for deployment of [marine cloud brightening] unless it was clearly established that no significant adverse consequences would result. There would also need to be an international agreement firmly in favour of such action,” concluded the paper.

Image: Death to Stock Photos

This post was first published on The Untweetable Truth (08/02/2014)