過去の温度変動を再構築するための長いツリーリングのクロノロジーにおける低周波信号
Jan Esper1, Edward R Cook, Fritz H Schweingruber
1Swiss Federal Research Institute WSL, Zuercherstrasse 111, 8903 Birmensdorf, Switzerland.
まとめ
長い木の輪の記録は,過去の気候の変動性と中世の温暖期 (MWP) を理解するために不可欠です. 私たちの研究は,北半球の樹輪データが,MWPをサポートして,多世紀間の気温傾向を保存できることを示しています.
科学分野:
- 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
- 気候科学 気候科学
- デンドロクロノロジー (Dendrochronology) とは
背景:
- 過去の気候の変動を正確に再構築することは,長期的な気温の動向を理解するために不可欠です.
- 中世の温暖期 (MWP) と20世紀の温暖化は,比較のために堅牢で長期の気候記録を必要とします.
- 樹輪年代記は,過去の気候条件を再構築するための貴重なプロキシを提供します.
研究 の 目的:
- 北半球の外熱帯の樹輪年代が,何世紀にもわたる気候変動の変動を保持する能力を実証するため.
- 過去1000年間の気温動向を再構築するためにツリーリングデータの使用を検証する.
- ツリーリングの証拠を用いて,中世の温暖期の大規模な発生を評価する.
主な方法:
- 北半球の外熱帯地域からの14の高品質のツリーリング年代表の選択.
- 大規模で,何世紀にもわたる気温の動向を保存するために,適切な分析方法の適用.
- 複合記録を作成するために,選択されたクロノロジーを平均化します.
主要な成果:
- 慎重に選択されたツリーリングの年代順は,一貫した,大規模な,複数世紀間の気温の傾向を保存することができます.
- 開発された方法は,木の輪データにおける気候の重要な変動の保存を保証します.
- 複合樹輪記録は,北半球の外熱帯地域全体で中世の温暖期が起こったことを支持しています.
結論:
- 樹輪記録は,過去数百年の時間スケールにおける過去の気温変動を再構築するための信頼できる情報源です.
- この研究は,MWPのような歴史的な気候イベントを理解するために,ツリーリングデータの使用を検証しています.
- 発見は,北半球の外熱帯における中世の温暖期の大規模な性質を支持する.
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