Item type |
紀要論文(ELS) / Departmental Bulletin Paper(1) |
公開日 |
1992-12-01 |
タイトル |
|
|
タイトル |
VARIATIONS OF THE PAST ATMOSPHERIC CH_4 CONCENTRATION DEDUCED FROM SITE-J ICE CORE, GREENLAND |
言語 |
|
|
言語 |
eng |
資源タイプ |
|
|
資源タイプ識別子 |
http://purl.org/coar/resource_type/c_6501 |
|
資源タイプ |
departmental bulletin paper |
ID登録 |
|
|
ID登録 |
10.15094/00003759 |
|
ID登録タイプ |
JaLC |
ページ属性 |
|
|
内容記述タイプ |
Other |
|
内容記述 |
P(論文) |
記事種別(英) |
|
|
|
en |
|
|
ABSTRACT |
論文名よみ |
|
|
その他のタイトル |
VARIATIONS OF THE PAST ATMOSPHERIC CH_4 CONCENTRATION DEDUCED FROM SITE-J ICE CORE, GREENLAND |
著者名よみ |
ナカザワ, タカキヨ
マチダ, トシノブ
タナカ, マサユキ
フジイ, ヨシユキ
アオキ, シュンジ
ワタナベ, オキツグ
|
著者名(英) |
NAKAZAWA, Takakiyo
MACHIDA, Toshinobu
TANAKA, Masayuki
FUJII, Yoshiyuki
AOKI, Shuhji
WATANABE, Okitsugu
|
著者所属(英) |
|
|
|
en |
|
|
Center for Atmospheric and Oceanic Studies, Faculty of Science, Tohoku University |
著者所属(英) |
|
|
|
en |
|
|
Center for Atmospheric and Oceanic Studies, Faculty of Science, Tohoku University |
著者所属(英) |
|
|
|
en |
|
|
Center for Atmospheric and Oceanic Studies, Faculty of Science, Tohoku University |
著者所属(英) |
|
|
|
en |
|
|
National Institute of Polar Research |
著者所属(英) |
|
|
|
en |
|
|
National Institute of Polar Research |
著者所属(英) |
|
|
|
en |
|
|
National Institute of Polar Research |
抄録(英) |
|
|
内容記述タイプ |
Other |
|
内容記述 |
Air samples in an ice core from Site-J, Greenland, were analyzed to reconstruct the variations of the atmospheric CH_4 concentration in the northern hemisphere during the last 400 years. The results showed that the CH_4 concentrations were fairly constant during the first 200 years, the values being about 750 ppbv, and then increased significantly. The pre-industrial levels of the CH_4 concentration obtained in this study were higher by 50-60 ppbv than those deduced from the Mizuho core, Antarctica. This implies that natural CH_4 sources were stronger in the northern hemisphere than in the southern hemisphere. Taking account of the fact that the present concentration differences between northern and southern high latitudes are almost 150ppbv, it is suggested that a large amount of CH_4 has been released into the atmosphere in the northern hemisphere due to anthropogenic activities and/or the atmospheric OH radicals have decreased more rapidly in the northern hemisphere than in the southern hemisphere. Assuming that the air was well mixed in the firn at Site-J, the age difference between the air in bubbles and surrounding ice was estimated to be about 102 years. It was, however, found that the CH_4 concentrations obtained on the basis of this age difference were delayed in their increase during the last 200 years, as compared with those in southern high latitudes. The cause could be attributed to the insufficient air exchange in the firn due to melt layers. Therefore, the age difference of the Site J ice core was thought to be less than 102 years. |
雑誌書誌ID |
|
|
収録物識別子タイプ |
NCID |
|
収録物識別子 |
AA10756213 |
書誌情報 |
Proceedings of the NIPR Symposium on Polar Meteorology and Glaciology
巻 6,
p. 156,
発行日 1992-12
|
出版者 |
|
|
出版者 |
National Institute of Polar Research |