A low-level penetration seeding experiment of liquid carbon dioxide in a convective cloud

Kenji Wakimizu, Koji Nishiyama, Yoshinori Suzuki, Kikuro Tomine, Mitsuru Yamazaki, Ataru Isimaru, Motoki Ozaki, Tosihisa Itano, Genichi Naito, Norihiko Fukuta

Research output: Contribution to journalArticlepeer-review

11 Citations (Scopus)


In order to bring large amounts of precipitation, the new seeding method using liquid carbon dioxide (LC) was suggested by Fukuta (1996a). The method was applied to the supercooled convective cloud in a post-frontal weather condition in northern Kyushu, Japan, on October 27, 1999. In the seeding experiment, LC seeding and the subsequent observation by aircraft were carried out and the features of a seeded echo were observed by radar. Consequently, the aircraft observation confirmed the further development of the seeded cumulus together with a fuzzy aspect of the cloud surface, which indicates the feature consisting of ice particles. Furthermore, the observed cloud top was quite consistent with the cloud top estimated by the thermodynamic analysis following parcel theory. Therefore, the observed results indicate the artificial effects by LC seeding. On the other hand, the radar observation confirmed an artificially induced echo, which showed spreading of the echo area and took a unique mushroom shape in the RHI pictures. The maximum width of the echo reached 24 km and the total amount of estimated radar precipitation of the seeded cumulus was approximately 2.4 million ton, traversing a distance of 60 km in 1 h 40 min. The observed and estimated results are consistent with the hypothesis of the new seeding method, which induces the dynamic and microphysical processes consisting of two fundamental processes. In addition, it was found that dynamical interaction between the seeded and the adjacent natural cumuli was an important factor in the formation of the secondary cumulus. The observational fact will give new viewpoint into the future seeding study.

Original languageEnglish
Pages (from-to)2239-2253
Number of pages15
JournalHydrological Processes
Issue number11
Publication statusPublished - 2002

All Science Journal Classification (ASJC) codes

  • Water Science and Technology


Dive into the research topics of 'A low-level penetration seeding experiment of liquid carbon dioxide in a convective cloud'. Together they form a unique fingerprint.

Cite this