In an era of increasing water scarcity and climate change, the controversial practice of cloud seeding is gaining renewed attention as a potential tool for boosting water supplies. Cloud seeding involves dispersing substances like silver iodide into clouds to stimulate rainfall or snowfall, but critics argue that it poses environmental risks and ethical concerns.
California has been at the forefront of recent cloud seeding efforts. The Santa Barbara County Water Agency has sponsored a seeding program since 1981, which a recent analysis found has increased precipitation by an average of 9-21% each winter over targeted watersheds (North American Weather Consultants, 2023). In 2023, the Santa Ana Watershed Project Authority launched a 4-year pilot program to assess the effectiveness of seeding for enhancing water supplies in Southern California (Santa Ana Watershed Project Authority, 2024).
Meanwhile, a group of atmospheric scientists has proposed a research roadmap to evaluate the feasibility of marine cloud brightening (MCB) as a method to offset climate change impacts (Atmospheric Sciences Research Group, 2023). MCB involves injecting salt spray into marine clouds to increase their reflectivity and reduce ocean warming, but the scientists stress that it is not a substitute for reducing emissions.
