マッデン-ジュリアン振動イベントは,グローバルなクラウド解析モデルによって現実的にシミュレートされています
Hiroaki Miura1, Masaki Satoh, Tomoe Nasuno
1Frontier Research Center for Global Change, Japan Agency for Marine-Earth Science and Technology, 3173-25 Showamachi, Kanazawa-ku, Yokohama, Kanagawa 236-0001, Japan. miurah@jamstec.go.jp
Science (New York, N.Y.)
|December 15, 2007
まとめ
マッデン-ジュリアン振動 (MJO) は,より正確にシミュレートされています. この気象モデリングの突破は,MJOの1ヶ月の予測の道を開き,世界の気候予測を改善します.
科学分野:
- 大気科学 大気科学
- 気候モデリング
- 気象学 気象学 気象学
背景:
- マッデン-ジュリアン振動 (Madden-Julian Oscillation,MJO) は,気候システムに影響を与える主要な世界的な気象現象である.
- MJOの正確なシミュレーションは,グローバル気象モデルの複雑さ,特に累積雲の仮定に関して,挑戦的です.
研究 の 目的:
- MJO イベントをシミュレートするための新しいモデルを開発し,利用する.
- MJOコンベクションの東方への拡散に影響を与える要因を調査する.
主な方法:
- 直接的な大気循環とクラウドカップリングによるグローバルクラウド解析モデルを採用しました.
- トポグラフィー,海面温度グラデーション,波の相互作用がMJOのタイミングに与える影響を分析した.
主要な成果:
- MJO イベントの特徴である東へのゆっくりとした移動をシミュレートしました.
- トポグラフィーとSSTグラデーションを含む,コンベクティブセンターの移行のための主要なドライバーを特定しました.
- MJOの1ヶ月の予測の実現可能性を実証しました.
結論:
- 直接結合された雲-大気モデルにより,MJOシミュレーションの改善が可能です.
- 正確な初期条件と高度なモデリングは,MJOイベントの予測に不可欠です.
- この研究は,長期にわたる天気と気候の予測の能力を高めています.
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