Grant-in-Aid for international Scientific Research
|Allocation Type||Single-year Grants|
|Research Institution||KYUSHU UNIVERSITY|
TAKAHASHI Tsutomu Faculty of Sciences, Kyushu University, Professor, 理学部, 教授 (20197742)
高橋 劭(1994) 九州大学, 理学部, 教授
KHOVADHANA K タイ, ソンカラ気象台, 台長
MORITA Osamu Faculty of Sciences, Kyushu University, Associate Professor, 理学部, 助教授 (70112290)
ISHIHARA Masahito Observation Department, Japan Meteorological Agency, Investigator, 観測部, 調査官
TSUDA Toshitaka Radio Atmospheric Science Center, Kyoto University, Associate Professor, 超高層電波研究センター, 助教授 (30115886)
FUKAO Shoichiro Radio Atmospheric Science Center, Kyoto University, Professor, 超高層電波研究センター, 教授 (30026249)
KHOVADHANA Kriengkrai Songkhla Weather Station, Thai Meteorological Agency Chief
HARIJONO Sri インドネシア技術評価応用庁, 気候改良研究部, 部長
GAGE K.S. 米国国立大気物理海洋研究所, 波動伝播研究室, 室長
小池 俊雄 長岡技術科学大学, 工学部, 助教授 (30178173)
中北 英一 京都大学, 防災研究所, 助教授 (70183506)
池淵 周一 京都大学, 防災研究所, 教授 (20026181)
坪木 和久 東京大学, 海洋研究所, 助手 (90222140)
山中 大学 京都大学, 超高層電波研究センター, 助教授 (30183982)
|Project Period (FY)
1993 – 1994
Completed(Fiscal Year 1994)
|Budget Amount *help
¥12,000,000 (Direct Cost : ¥12,000,000)
Fiscal Year 1994 : ¥6,500,000 (Direct Cost : ¥6,500,000)
Fiscal Year 1993 : ¥5,500,000 (Direct Cost : ¥5,500,000)
|Keywords||Asian Winter Monsoon Rain / Precipitation Mechanism of Monsoon Rain / Precipitation and Convection / Asian Water Circulation / モンスーン雨 / 熱帯の雨|
The study of Asian Monsoon rain is important not only for people living in the area but also for a better understanding of global water circulation. However, because it is difficult to conduct aircraft observations due to the expected high content of supercooled water in cloud, the study of precipitation processes has been slow in progress.
Our research group has developed videosonde system to study the precipitation processes. The videosonde is a balloon-borne videosonde system from which images of precipitation particles > 0.5 mm in diameter are acquired by a video camera using two sources of stroboscopic illumination.
In our observations in Thailand, thirteen videosondes were launched in Songkhla (7*N,101*E)during the period from November 4 to 25,1993, and fourteen videosondes were launched in Surat Thani (9*N,99*E)during the period from October 23 to November 20,1994. In the latter case, videosondes were launched in close collaboration with the C-band doppler radar which belongs to Thai Meteorological Agency.
Highlights of the research are :
1. There are two types of rain system : One is the equatorial rain system approached from lower latitude, and the second is the monsoon rain system which developed under intence high pressure over the continent extending over the Indo-China Peninsula.
2. Different precipitation processes is found in each rain system. In the equatorial rain system, warm rain process dominates, while upper-level graupel formation process as well as low-level warm rain process is active in the monsoon rain system.
3. According to the doppler radar analysis, the monsoon rain system is characterized by additional upper-level lifting.
4. Larger raindrops are produced in the monsoon rain system than in the equatorial rain system probably because of the strong interaction between graupel falling from above and raindrops grown by warm rain process.