Nuclear bomb tests during the Cold War may have changed rainfall patterns thousands of miles from the detonation sites, new research has revealed.
Scientists at the University of Reading have researched how the electric charge released by radiation from the test detonations, carried out predominantly by the US and Soviet Union in the 1950s and 1960s, affected rainclouds at the time.
The study, published in Physical Review Letters, used historic records between 1962-64 from a research station in Scotland. Scientists compared days with high and low radioactively-generated charge, finding that clouds were visibly thicker, and there was 24% more rain on average on the days with more radioactivity.
Professor Giles Harrison, lead author and Professor of Atmospheric Physics at the University of Reading, said: "By studying the radioactivity released from Cold War weapons tests, scientists at the time learnt about atmospheric circulation patterns. We have now reused this data to examine the effect on rainfall.
"The politically charged atmosphere of the Cold War led to a nuclear arms race and worldwide anxiety. Decades later, that global cloud has yielded a silver lining, in giving us a unique way to study how electric charge affects rain."