マウンダー・ミニウム期における地域的な気候変動の太陽による強制作用
D T Shindell1, G A Schmidt, M E Mann
1NASA Goddard Institute for Space Studies and Center for Climate Systems Research, Columbia University, New York, NY 10025, USA.
Science (New York, N.Y.)
|December 12, 2001
まとめ
太陽光照射量の変化は,地球全体の気温のわずかな変化をもたらしたが,北半球の大陸では地域的な冷却が顕著であった. この気候反応は,北極振動/北大西洋振動の状態と関連していた.
科学分野:
- 気候科学 気候科学
- 古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは
- 大気科学 大気科学
背景:
- マウンダー最小期 (17世紀後半) は,低太陽活動期を表しています.
- 過去の気候変動の変動を理解することは,将来の気候変動を予測する上で極めて重要です.
研究 の 目的:
- マウンダー最小値と18世紀後半の間の太陽放射線の変動に対する気候反応を調査する.
- グローバルと地域の両方の温度変化を分析するために.
主な方法:
- 気候モデルを使用して,気候反応をシミュレートしました.
- 表面温度の経験的再構築とプロキシデータを採用した.
主要な成果:
- 世界の平均気温は,最小限の変化 (0.3-0.4°C) を示した.
- 地域的な気温の大きな変動が観察され,特に北半球の大陸の冬の寒さ (1~2°C) が観察されました.
- 気候モデルの結果は,北極振動/北大西洋振動の低インデックス状態へのシフトを示した.
結論:
- 太陽光照射量の変化は,世界の平均気温の小さな変化でも,地域の気候パターンに大きく影響します.
- 北極振動/北大西洋振動は,太陽力への地域の気候反応を媒介する上で重要な役割を果たしています.
- モデルの発見は,歴史的な記録とプロキシデータと整合し,シミュレートされた気候反応を検証します.
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