ONO Kazuo Kishikawa Tokusyu Barubu, Inc., Section Chief, 課長
YAJIMA Nobuyuki Inst.Space Astro.Sci., Prof., 教授 (30200489)
OKANO Shoichi Nat.Inst.Pol.Res., Prof., 教授 (10004483)
AOKI Shuji Tohoku Univ., Fac.of Sci., Asso.Prof., 理学部, 助教授 (00183129)
|Budget Amount *help
¥11,800,000 (Direct Cost : ¥11,800,000)
Fiscal Year 1997 : ¥1,300,000 (Direct Cost : ¥1,300,000)
Fiscal Year 1996 : ¥4,600,000 (Direct Cost : ¥4,600,000)
Fiscal Year 1995 : ¥5,900,000 (Direct Cost : ¥5,900,000)
For atmospheric environmental problems such as the depletion of stratospheric ozone and the global warming, it is indispensable to clarify variations of relevant trace gases in the stratosphere. However, our knowledge of this issue is still insufficient, due primarily to difficulties in their measurements. In this study, we developed a small and simple sampling system to collect stratospheric air.
For designing our sampler, we launched a small balloon system and then recovered it at Syowa Station, Antarctica. Considering the results of this preliminary experiment, we decided to employ a GPS receiver for tracking the sampler, a Rawinsonde for backup and a radio beacon transmitter for searching the gondola after landing.
The sampler developed in this study consists mainly of a sample container, a control circuit unit, batteries, a GPS receiver and a transmitter, and all parts were assembled in an aluminum frame with aluminum honeycomb for a shock absorber. The sampler was equipped with a t
urn-over mechanism of the gondola to avoid contamination of sample air due to gases from the gondola. Total weight of the sampler was about 11 kg. The sample container with a volume of 15l was made of stainless steel, and its inner wall was electrically polished. Electromagnetic and manual valves, made of stainless steel, were attached in series to the container.
A balloon system for the sampler was comprised mainly of a specially-designed 4.5 kg rubber balloon, a cross-type parachute, a gondola, a balloon burst sensor, a main rope cutter and a Rawinsonde. The distance between the balloon and the gondola was set to about 10 m, and a total weight of the system was approximately 17 kg. A new gas handling unit was also prepared to simplify the injection of He gas into the rubber balloon.
The sampler developed was launched at Syowa Station in January 1997 and recovered after collecting stratospheric air at 20 km. In 1997, to improve the performance of the sampler, we also developed a method for making the inner wall of the container clearer and a new-type open/close valve which is actuated using gunpowder. Less