Given the complexity and global nature of weather, however, this is almost certain to create non-trivial effects on other countries.
...And even if it could miraculously be prevented from actually causing any local negative weather events in other countries, it would certainly be perceived to do so, because terrible freak droughts/floods/etc. will continue to happen as always, and people will go looking for someone to blame, and the geoengineering project next door will be an obvious scapegoat.
Like how the US government once tried to use cloud-seeding (silver iodide) to weaken hurricanes, and then one time a hurricane seemed to turn sharply and hit Georgia right after being seeded, and everyone blamed the cloud-seeding, and sued, and shut the program down, …even though it was actually a coincidence! (details) (NB: I only skimmed the wikipedia article, I haven’t checked anything)
...And even if it could miraculously be prevented from actually causing any local negative weather events in other countries, it would certainly be perceived to do so, because terrible freak droughts/floods/etc. will continue to happen as always, and people will go looking for someone to blame, and the geoengineering project next door will be an obvious scapegoat.
Like how the US government once tried to use cloud-seeding (silver iodide) to weaken hurricanes, and then one time a hurricane seemed to turn sharply and hit Georgia right after being seeded, and everyone blamed the cloud-seeding, and sued, and shut the program down, …even though it was actually a coincidence! (details) (NB: I only skimmed the wikipedia article, I haven’t checked anything)