Cloud Nuclei from Launches and Firings of Solid Rocket Boosters


  • Edward E. Hindman, II Department of Atmospheric Science
  • F. Kirk Odencrantz
  • William G. Finnegan Department of Atmospheric Science Colorado State University


Ground clouds from launches of Titan III rockets were bright, white, and cumulus-like early in their lives and contained up to 3.5 g m^-3 of liquid in micron to millimeter-size droplets. The clouds traveled up to 76 n m and were visible and detectable from aircraft up to 5 hours after launch. The clouds contained concentrations of cloud condensation nuclei (CCN) significantly above values nearby air for periods of 3 to 5 hours after launch. The initial production of CCN active at 0.5% supersaturation is equivalent to a 30 minute emission by the city of Denver, Colorado. Concentrations of ice nuclei (IN) in the clouds could not be determined because of inconsistent results between measurement techniques. Concentrations of IN in exhaust clouds from nozzle-up solid rocket booster firings are at least two to three orders greater than background values. In comparison, concentrations of IN one to two orders greater than background are believed sufficient to augment precipitation from winter mountain clouds.




Scientific Papers