The City Council in Alameda, Calif., voted to stop tests of a device that could one day cool the Earth. Scientists and city staff had previously concluded the tests posed no risk.

The damage was unusual, experts say, because turbines are built to withstand extreme weather. Iowa is a wind powerhouse, with thousands of turbines.

© Charlie Neibergall/Associated Press

Researchers had been testing a sprayer that could one day be used to push a salty mist skyward, cooling the Earth. Officials stopped the work, citing health questions.

© Ian C. Bates for The New York Times