Abstract
A diagnostic technique for targeting during airborne seeding experiments has been developed for the Sierra Cooperative Pilot Project (SCPP). This technique was used operationally during SCPP for real-time guidance to aircraft, providing 1) the location and orientation of the seeding line required to target ice particles created by seeding to a specified ground location and 2) an estimate of the areal coverage of the seeding effect on the ground. Procedures to use this technique as a real-time guidance tool during seeding operations in Sierra wintertime storms are discussed.
Three evaluation studies of the targeting method are presented. These include 1) comparisons of diagnosed wind fields with those measured by aircraft; 2) comparisons of ice particle growth rates and habits within seeded cloud regions with those used in the targeting computations; and 3) comparison of radar echo evolution within seeded cloud regions with calculated particle trajectories.