In October 2010 the Convention on Biodiversity under the United Nations Environment Programme adopted a resolution which placed a moratorium on geoengineering unless it can be proven that the method in question can be shown to not have an adverse effect on biodiversity. Cloud seeding is however not considered to be geoengineering. Cloud seeding involves the spraying of selected clouds with chemicals, usually silver iodide, either from aircraft or from the ground through the use of generators or rockets. This leads to the formation of ice crystals, which grow in size until they reach the necessary weight to fall in the form of rain. Silver iodide can cause possible residual injury to humans and mammals with intense or continued but not chronic exposure.
Of course I can understand that the population is desperate, but doubts do remain as to whether cloud seeding is truly effective - or safe (what are indeed the potential effects on the air, water and soil of the chemicals used?).