chaff:
Strips of metal, foil, or glass fiber with a metal content, cut into various lengths and having varying frequency responses, that are used to reflect electromagnetic energy as a radar countermeasure. These materials, usually dropped from aircraft, also can be deployed from shells or rockets.
http://www.dynomat.com/
Historical Milestone Timeline:
June 4, 2002 * Melbourne, FL: Dyn-O-Mat Inc.’s team of experts continues their mission of significantly reducing the destructive power of hurricanes.
July 19, 2001 * West Palm Beach, FL: Using a Canaberra, Dyn-O-Mat became the first people ever take a cloud off of Doppler radar.
For the last 2 years extensive field-testing has been taking place. Including: cutting a cloud in half using a crop duster.
For the last 3 years the Dyn-O-Mat team has been doing extensive laboratory research.