Cloud Seeding Experiment for Precipitation Augmentation with Aircraft In-situ Measurements

Abstract

As one of the physical evaluation techniques of seeding effects, cloud seeding experiments were conducted utilizing an instrumented aircraft, with the use of dry-ice pellets in cold clouds and hygroscopic flares and salt micro-powders in warm clouds as a seeding agent. We demonstrated from the in-situ measurements that dry-ice pellet seeding of mixed-phase orographic clouds were effective, based on the comparison of estimated radar reflectivity factor, ice water content, or precipitation intensity from the 2D images of ice particles between seeded portions and their surroundings. The observational results we obtained so far showed that hygroscopic seeding of warm clouds might be effective under limited conditions.