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Because if you seed all the clouds in areas where it doesn’t rain very often, you ran the risk of causing a drought. However, in real life, silver iodide can actually prevent any precipitation at all from forming in the cloud, snow, rain or hail. First, it may be true that under laboratory conditions silver iodide creates snow instead of hail. It’s not clear that cloud seeding is all that effective and there are reasons to question each of the arguments you just read. The study found that in an area where cloud seeding was used there was reduced hail damage compared to previous years. One study conducted in a farming region in the central United States, for example, directly monitored crop damage due to hail. Local studies A few local studies also support the value of cloud seeding. These positive results suggest that cloud seeding should also be effective in protecting fields and farms in the United States. In some Asian countries, for example, cloud seeding has been successfully used to control precipitation in urban areas. Evidence from Asia There is evidence about the effectiveness of cloud seeding from several countries around the world. Hail usually forms water vapor that is close to the freezing point However, when experimenters added silver iodide to cold water vapor in the laboratory, they often observed light snow forming instead of hail pellets. Laboratory experiments Experiments in the laboratory support the idea that cloud seeding is effective. Several pieces of evidence suggest that cloud seeding has been effective in protecting crops from hail. This makes the clouds produce harmless rain or snow instead of hail. In cloud seeding, the chemical silver iodide is sprayed on storm clouds from an airplane. Over the last few decades, a method of reducing hail, called "cloud seeding," has been tried. Hail pellets can fall with great force and destroy crops in the field. Hail-pieces of ice that form and fall from clouds instead of snow or rain-has always been a problem for farmers in some areas of the United States.