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How would cloud whitening use seawater droplets and salt crystals to reflect sunlight?

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Illustration of various geoengineering techniques to address climate change, including carbon capture and storage methods like artificial trees, industrial scrubbers, and deep ocean CO2 storage, as well as solar reflectance strategies such as sulfur aerosols, reflective crops, cloud whitening, and orbital mirrors. The scene shows these interventions applied to land, sea, and atmosphere, with labeled features explaining each process. — Geoengineering Various geoengineering proposals designed to increase solar reflectance or capture and store carbon.

Cloud whitening is an untested geoengineering proposal intended to increase the reflectance of Earth’s cloud cover to reduce the amount of solar radiation reaching the surface.12

The process would utilize specialized spraying devices mounted on land or oceangoing vessels to expel a pressurized mist of seawater and dissolved salts up to 300 metres (1,000 feet) into the air. As the water droplets evaporate, they leave behind bright salt crystals that reflect incoming sunlight.12

Additionally, these salt crystals are expected to function as condensation nuclei, facilitating the formation of new water droplets. This process would theoretically increase overall marine cloud coverage, thereby reflecting even more solar radiation back into space.12