[A-CG31] Aircraft and UAV Observations for Earth-planetary sciences

[ACG31-P03] Cloud seeding experiment for precipitation augmentation with aircraft in-situ measurements

*Narihiro Orikasa¹, Masataka Murakami^2,1, Atsushi Saito³, Takuya Tajiri¹, Yuji Zaizen¹, Taro Shinoda² (1.Meteorological Research Institute, 2.Nagoya University, ISEE, 3.Japan Meteorological Agency)

Keywords:Cloud Condensation Nuclei (CCN)/Ice Nucleating Particles (INP), Hygroscopic Seeding, Hygroscopic Flare and Salt Micro-powder, Glaciogenic Seeding, Silver Iodide Flare and Dry-ice Pellet

As one of the physical evaluation techniques of cloud seeding effects, we have conducted several field campaigns for cloud seeding experiment utilizing an instrumented aircraft in Japan and in the United Arab Emirates. The seeding agents used were dry-ice pellets and silver iodide flares in cold clouds and hygroscopic flares and salt micro-powders in warm clouds.

We demonstrate 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 regions and their surroundings.

The observational results we obtained so far showed that hygroscopic seeding of warm clouds might be effective under limited conditions. The size distributions of cloud droplets near the cloud base were compared between seeded cloud regions and unseeded regions.

The flare seeding plumes generated in midair were sampled and measured with the instrumented aircraft. The size distributions and CCN and INP abilities of those particles in different types of flares are presented.