Hydroclimatic conditions during the first half of the 20th century in the bonin (ogasawara) islands

• 資料種別: 記事
• タイトル: Hydroclimatic conditions during the first half of the 20th century in the bonin (ogasawara) islands
• 著者標目: ヤカベ, ユウ; Iijima, Yoshihiro; Yakabe, Yu; イイジマ, ヨシヒロ
• 出版年月日等: 2009
• 出版年（W3CDTF）: 2009
• タイトル（掲載誌）: Geographical Reports of Tokyo Metropolitan University
• 巻号年月日等（掲載誌）: 44
• 掲載号: 44
• 掲載ページ: 85-93
• 掲載年月日（W3CDTF）: 2009
• ISSN（掲載誌）: 03868710
• 出版事項（掲載誌）: Department of Geography, Tokyo Metropolitan University
• 本文の言語コード: en
• 件名標目: hydroclimate; potential evaporation; wetness index; small pan evaporation; the Bonin (Ogasawara) Islands
• 対象利用者: 一般
• 関連情報（URI）: http://hdl.handle.net/10748/3826; https://tokyo-metro-u.repo.nii.ac.jp/records/3073
• 連携機関・データベース: 国立情報学研究所 : CiNii Research; https://cir.nii.ac.jp/
• 提供元機関・データベース: 学術機関リポジトリデータベース; https://irdb.nii.ac.jp

• 要約等: According to past studies based on long-term variations in precipitation and air temperature, climate in Chichi-jima of the Bonin (Ogasawara) Islands was rather wetter during the first half of the 20th century than during the latter half through present. The present study revealed actual hydroclimatic conditions using detailed meteorological components on monthly basis in the Annual Report of the Central Meteorological Observatory in terms of estimating potential evaporation and wetness index. As results of reevaluation of potential evaporation, Thornthwaite method underestimates potential evaporation especially during the cold season (from December to April) due to lower air temperature relatively to solar radiation. Thus, frequency of semi-dry month increased to 40-50% in this season. Annual wetness index is 1.24 in average (1907-1939) and only 5 years with less than 1.0 (semi-dry year). Small pan evaporation observed from 1931 to 1939 in Japan exhibits that Chichi-jima was one of the largest evaporation sites, namely the driest site in Japan although hydroclimatic conditions was wetter during the period.
• オンライン閲覧公開範囲: インターネット公開
• 掲載誌（NCID）: AA00200173; https://ci.nii.ac.jp/ncid/AA00200173
• 連携機関・データベース: 国立情報学研究所 : 学術機関リポジトリデータベース（IRDB）（機関リポジトリ）; https://irdb.nii.ac.jp
• 提供元機関・データベース: 東京都立大学 : みやこ鳥

• 要約等: According to past studies based on long-term variations in precipitation and air temperature, climate in Chichi-jima of the Bonin (Ogasawara) Islands was rather wetter during the first half of the 20th century than during the latter half through present. The present study revealed actual hydroclimatic conditions using detailed meteorological components on monthly basis in the Annual Report of the Central Meteorological Observatory in terms of estimating potential evaporation and wetness index. As results of reevaluation of potential evaporation, Thornthwaite method underestimates potential evaporation especially during the cold season (from December to April) due to lower air temperature relatively to solar radiation. Thus, frequency of semi-dry month increased to 40-50% in this season. Annual wetness index is 1.24 in average (1907-1939) and only 5 years with less than 1.0 (semi-dry year). Small pan evaporation observed from 1931 to 1939 in Japan exhibits that Chichi-jima was one of the largest evaporation sites, namely the driest site in Japan although hydroclimatic conditions was wetter during the period.
• 関連情報（URI）: http://hdl.handle.net/10748/3826
• 連携機関・データベース: 国立情報学研究所 : CiNii Research; https://cir.nii.ac.jp/
• 提供元機関・データベース: CiNii Articles
• NII論文ID: 110008608628