一般循環モデルシミュレーションにおけるほぼ2年毎の振動信号
Science (New York, N.Y.)
|September 3, 1993
まとめ
準二年振動 (QBO) は,赤道平流圏の大気パターンであり,一般循環モデルを使用してシミュレートされました. これらのモデルは,QBOの期間と構造を成功裏に再現し,気候モデリングの有望さを示しました.
科学分野:
- 大気科学 大気科学
- 気候のダイナミクス
- ストラトスフィアの物理学
背景:
- 準二年振動 (quasi-biennial oscillation,QBO) は,赤道下の平流圏における東風と西風の交替によって特徴づけられる自然の大気現象である.
- この振動は,赤道に近似的な対称性を示し,ピーク幅は20°Sと20°Nの間であり,平均期間は約27ヶ月です.
研究 の 目的:
- QBOの起源を調査し,特に熱帯圏から発生する湿った赤道波からのモメンタム堆積の役割を調査する.
- アドホックパラメータ化なしでQBOをシミュレートする一般流通モデル (GCM) の能力を評価する.
主な方法:
- 3つの異なる10年間のシミュレーションは,異なるGCMを使用して実施されました.
- モデルは,熱帯圏の糖尿病性プロセス,赤道波の興奮,および平流圏のダッピングの間の相互作用を捉えるように設計されました.
主要な成果:
- 3つのGCMシミュレーションはすべて,平流圏でQBO信号を成功裏に開発しました.
- シミュレーションされたQBOは,観測データと一致する周期と空間的伝播構造を示した.
- シミュレートされたQBOの振幅は観測値より低かった.
結論:
- GCMは,特殊なパラメータ化なしでQBOの基本的な特性をシミュレートすることができ,気候モデリングの有望な進歩を示しています.
- 観測されたQBO振幅を正確に複製するために,モデルのさらなる精細化が必要である.
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