ホロセンの初期に発生した太陽力への太平洋熱帯地域のダイナミックな反応
Thomas M Marchitto1, Raimund Muscheler, Joseph D Ortiz
1Department of Geological Sciences and Institute of Arctic and Alpine Research, University of Colorado, Boulder, CO 80309, USA. tom.marchitto@colorado.edu
Science (New York, N.Y.)
|December 4, 2010
まとめ
この研究は,バジャカリフォルニア沖のホロセーン海面温度を明らかにし,太陽周期とエルニニョ-南方振動 (ENSO) ダイナミクスに関連した初期の暖かさを示しています. これらの発見は,過去の気候の変動性と海洋の反応に関する洞察を提供します.
科学分野:
- パレオセアノグラフィーとは
- 気候科学 気候科学
- マリン・ジオケミストリー (海洋地化学)
背景:
- エルニーニョ・サザン・オシレーション (ENSO) は,バハ・カリフォルニア沖の年間間の海面温度 (SST) 変動に大きく影響します.
- 過去のENSOの行動とその要因を理解することは,将来の気候パターンを予測する上で極めて重要です.
研究 の 目的:
- バハ・カリフォルニア州南部の西海岸から高解像度のホロセンのSST記録を再構築する.
- 過去のSST,太陽の変動,およびENSOのような条件の間の関係を調査する.
主な方法:
- 高解像度マグネシウム/カルシウム (Mg/Ca) プロキシを使用して,過去の海面温度を測定しました.
- 太陽の変動性に関する宇宙原核素プロキシと相関するSST変動.
主要な成果:
- ホロセンの初期から中期にかけてのSSTは,東方赤道太平洋の冷却と軌道強制シミュレーションと整合して,より涼しかった.
- 初期のホロセンのミレニアムスケールのSST変動は,太陽の最小値と相関しており,エルニーニョのような条件を示唆しています.
- 観測されたパターンは,理論的なパターンと一致しています.
- 海洋ダイナミック・サーモスタット
- ENSOの放射線強制への反応.
結論:
- Mg/Caのプロキシ記録は,北太平洋におけるホロセンの海洋大気動態に関する貴重な洞察を提供します.
- 太陽の変動は,ホロセンの初期にENSOの行動に影響を与えた可能性がある.
- この発見は,ENSOの外部気候強制への反応の理論モデルを裏付けている.
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