Cold War spurs attempts to modify the weather

In 1971, amid Soviet claims of having successfully suppressed hail in the Caucasus Mountains, the National Hail Research Experiment (NHRE) was inaugurated at NCAR to test hail suppression techniques and study the physics of summer storms in the "Hail Alley" of northeast Colorado, northwest Kansas, southeast Wyoming, and southwest Nebraska. NHRE became the largest weather modification project in the world, gathering the first direct evidence of how rain and hail are formed. Results were equivocal at best; for one thing, the decade of the 1970s was the second driest decade on record, and in one summer, 1973, only six "hail days" were declared, compared to 22 hail days in 1972. By 1975, the seeding program was suspended, two years short of the original goal. Thirty five years later, NCARís Research Applications Program operates a vigorous weather modification program looking into cloud seeding in drought-stricken areas around the world.