2001 Fiscal Year Final Research Report Summary
Study on the complex process between cloud physics and cloud chemistry related to global warming and acidification using quasi-real-scale artificial cloud
| Project/Area Number |
11304027
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (A)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Meteorology/Physical oceanography/Hydrology
|
|---|
| Research Institution | HOKKAIDO UNIVERSITY |
|---|
Principal Investigator |
HARIMAYA Toshio Hokkaido Univ., Grad. School of Sci., Prof., 大学院・理学研究科, 教授 (90001859)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
YAMAGATA Sadamu Univ., Grad. School of Eng., Inst., 大学院・工学研究科, 助手 (80220242)
TAKAHASHI Tsuneya Hokkaido Univ. of Edu., Fac. of Edu., Asso. Prof., 教育学部, 助教授 (60236297)
MURAMOTO Ken-ichiro Kanazawa Univ., Fac. of Eng., Prof., 工学部, 教授 (70042835)
|
|---|
| Project Period (FY) |
1999 – 2001
|
| Keywords | artificial cloud / global warming / acidification / cloud physics / cloud chemistry / complex process / cloud physics experimental system / cloud modeling |
|---|
| Research Abstract |
Study on the process of cloud formation - The microphysical process of artificial cloud formation was studied using a quasi-real-scale cloud physics experimental system. This is the first study to show that aerosol is activated by an increase in relative humidity in air mass and that the activated aerosol grows to cloud droplet by condensation growth while the air mass is rising. This is also first study in which the effects of various parameter on the size distribution of cloud droplets have been quantified by actual measurements. Calculations on cloud droplet growth using a cloud model were carried out in stead of experiments in some cases. It enable to consider covering a wide parameter field about their influence parameters. In order to confirm that the experimental results accurately reflect that in the natural atmosphere, aerial observations were carried out to determine the relationship between aerosol number concentration under a cloud base and cloud droplet number concentration in a cloud.
Study on acid rain - The acidification mechanism on three formation processes of precipitation, namely, cloud droplet, rain drop and snow particle should be considered in order to understand the process by which acid rain is generated. First, the acidification of cloud droplets in sea fog was studied by observations carried out on a ship at sea. Next, oxidation experiments on sulfurous acid ions were carried out using a cloud physics experimental system with a long vertical mine shaft. The ions were oxidized during their passage up to the top of a vertical mine shaft of 430 m in height. The reaction speed was faster than that in an experiment using bulk solution in the laboratory. We also reviewed reports on gas scavenging by snow particles, as the mechanism by which snow particles are acidified is considered to be an important research subject.
|
