Could cloud seeding have caused the torrential rains in Pakistan?

JR and John are pathetic, Todd is right. Climate changes don't necessarily create "extreme weather" which will destroy the world. Extreme weather has and always will happen, anthropogenic global warming or not. Think of this, climate is the study of weather over months and years, not days and weeks! So you can throw their answers out the window immediately. As for seeding, you are asking a very complex question regarding a lot of cloud micro-physics. Silver Iodide is the most common "seeding agent" these days, but it should be said it is an "ice nuclei", and it is used in environments with sufficient amounts of supercooled liquid water to which it will act as a nuclei for that supercooled water to freeze upon. ONce this occurs, the Bergeron–Findeisen process develops precipitation as the ice crystals grow via deposition. Either way, we are getting way too deep into the scientific process. What directly caused the heavy rains was something us atmospheric scientists call deep, moist convection, or thunderstorms. Atmospheric flows (which I won't delve into here) had a tendency to to develop these thunderstorms over the same areas for a prolonged period of time, thus causing the heavy rains. It has been tried through the years (in funded studies and experiments) to seed clouds in various ways, but these experiments are on much smaller scales (think individual ulus clouds), not on large scale thunderstorms which can be orders of magnitude larger than the experiments done in the past. It would take fleets of airplanes and insane logistics to even try and seed thunderstorms, if not entirely impossible due to the short lifespan and extreme updrafts/downdrafts in thunderstorms (not conducive to safe flying!). So no, it is highly unlikely if not impossible for any cloud seeding to have any part in the heavy rains over Pakistan.