Amid two decades of drought, cloud seeding — using airplanes or ground equipment to waft rain-and-snow-making particles into clouds — is on the rise in the Rockies. Colorado has a long history of cloud seeding, said Scott Griebling, water resources engineer with the St. Vrain and Left Hand Water Conservancy District, which launched its first seeding program this winter near the Denver metro area. “All of those programs have been on the west part of the state. And this program is the first on the east part of the state.” No small part of the growth is due to intense pressure drought is placing on the Colorado River and its tributaries that supply water to millions of people from Wyoming to Los Angeles. But in the Rockies, cloud seeding these days has a full embrace from local and state officials eager for a not-too-expensive way to put more water in streams, rivers and especially the big Colorado River system reservoirs that hit record lows last year. Their approach: shoot silver iodide into clouds, where moisture binds to the particles, forms ice and falls as snow. That snowpack high in the mountains serves as year-round cold storage for water that's released as it melts.
Iowa House lawmakers advanced a bill prohibiting the intentional emission, injection or release of any chemicals into the atmosphere to affect weather, temperature, climate or intensity of sunlight.
