An international team of researchers, including Virginia Tech scientists Xiaofeng Wang and Boris A. Vinatzer, has identified fungal proteins that can trigger ice formation at relatively warm subzero temperatures. Their findings were published in Science Advances.

This discovery could open the door to new ways of influencing the weather.

Cloud seeding works by releasing particles known as ice nucleators into clouds. These particles cause water droplets to freeze into ice crystals. As more water attaches, the crystals grow larger and heavier. Eventually, they fall, melt as they pass through warmer air, and reach the ground as rain.

Silver iodide is the most commonly used ice-nucleating material, but it is highly toxic. The researchers suggest that fungal proteins could provide a safer alternative.

“If we learn how to cheaply produce enough of this fungal protein, then we could put that into clouds and make cloud seeding much safer,” said Vinatzer, professor in the School of Plant and Environmental Sciences.