トロポスフィアの地域14CO2オフセット:規模,メカニズム,影響
B Kromer1, S W Manning, P I Kuniholm
1Heidelberger Akademie der Wissenschaften, Institut für Umweltphysik der Universität Heidelberg, Im Neuenheimer Feld 229, D-69120 Heidelberg, Germany. bernd.kromer@iup.uni-heidelberg.de
まとめ
放射性炭素年代測定は,一貫した大気中の二酸化炭素 (CO2) に基づいています. この研究では,地域的なCO2の変動が発見され,年代測定の正確性と古気候研究に影響を与えました.
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,古代気候学 (paleoclimatology) とは
- 放射性炭素年代測定法による年代測定
- 大気科学 大気科学
背景:
- 放射性炭素年代測定法では,北半球における高気圏の二酸化炭素 (CO2) 濃度が均一であると仮定する.
- 以前の研究では,低緯度から中緯度におけるこの仮定を一般的に支持していた.
研究 の 目的:
- トロポスフィアの (14) CO(2) レベルにおける潜在的な地域的変動を調査する.
- これらの変動が放射性炭素年代測定と古気候再構築に与える影響を評価する.
主な方法:
- 南ドイツとアナトリアの樹輪 (14) Cデータの比較.
- 短期的な地域 (14) CO(2) オフセットの分析.
主要な成果:
- ツリーリングのデータは,一般的に,均一な熱帯 (14) CO (((2) の仮定を支持しますが,短期的な地域的な相殺を明らかにします.
- これらのオフセットは,低太陽磁気活動と大気冷却の期間中の平流層の (14) C 流動の影響を受け,強化された季節的 (14) CO (((2) サイクルに関連しています.
結論:
- 短期的な地域的 (14) CO(2) 変動が起こり,均一性の仮定に異議を唱える可能性があります.
- これらのオフセットを理解することは,正確な古気候研究と高解像度の考古学的年代測定に不可欠です.
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