Chaff seeding

From Glossary of Meteorology

chaff seeding

The practice of releasing radar chaff, which is aluminum or aluminum coated plastic strips or needles, into the atmosphere for the purpose of obtaining a strong radar reflecting signal in an otherwise weakly reflecting environment.

Chaff seeding, as a research technique, has been used to study the motion, deformation, transport, and mixing processes of the atmosphere on scales from a few meters to a few kilometers. Chaff seeding has also been used on the hypothesis that corona discharge from the needle tips could reduce lightning from thunderstorms.
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