Nuclear radioactive dust is certainly not a good thing. But new research suggests that charged particles released by Cold War nuclear tests may have contributed to rainfall thousands of kilometers away, as the electric charge in the air condenses water droplets into rain. From the 1950s to the early 1960s, countries such as the United States and the Soviet Union conducted many nuclear tests on the ground.
Nuclear radiation dust can have a subtle effect on the atmosphere. The charged particles released during radioactive decay collide with the atoms and molecules around them, creating more charged particles that are adsorbed to dust and water droplets, sometimes large enough to land on the ground.
Scientists analyzed Cold War rainfall records and found that clouds were more likely to thicken and rain when radioactive dust was above average. The study was published in the journal Physical Review Letters.