Saltwater film in clouds to cool Earth?

Geoengineering Technique Will Help Reflect Back More Sunlight

Washington: Amid growing concern over global warming, scientists have come up with an unique scheme to cool the earth with the help of a geoengineering method that would increase cloud reflectivity over the ocean.

Under the scheme, the scientists would increase cloud reflectivity over the ocean by spraying them with an ultra-fine saltwater mist from ships, a report in the Scientific American journal said.

“The clouds, containing more particles, would cast enough sunlight back into space to at least partially offset the warming effects of all that CO ² from burningfossil fuels,” the researchers said.

They added, “After all, clouds already reflect more of the sun’s radiation back into space than the amount trapped by human emissions of CO ² . So why not make them even more effective.”

Stephen Salter, an emeritus professor of engineering design at the University of Edinburgh, who is leading the research said, “marine cloud brightening could be done by populating the world's oceans with up to 1,500 ships of a somewhat exotic design — sometimes known as albedo yachts.”

“Each vessel would be remote-controlled, wind-powered, and capable of generating (via turbines dragged through the water) the electricity required to create a mist of seawater and loft it 1,000 meters into the atmosphere,” he added. Scientists have mixed reactions to the idea, which was first proposed in 1999.

For instance, Andy Jones at the Hadley Center for Climate Prediction and Research thinks if marine cloud brightening were deployed in the Atlantic, it might help turn the Amazon rainforest into a desert by cooling the South Atlantic, which would lead to less evaporation from the ocean, thus reducing rainfall. PTI