初期のホロセンの大気中のCO2濃度における世紀のスケールのシフト
1Laboratory of Palaeobotany and Palynology, Utrecht University, Budapestlaan 4, 3584 CD Utrecht, Netherlands. Netherlands Centre for Geo-ecological Research, Faculty of Earth Sciences, Free University, De Boelelaan 1085, 1081 HV Amsterdam, Netherla.
まとめ
化石の木の葉は,過去の大気中の二酸化炭素濃度を明らかにしています. 初期ホロセンの二酸化炭素濃度は,以前に推定されたよりも高く,300 ppmvを超えました.
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
- パレオボタニーは古植物学です.
- 地質化学 地質化学
背景:
- 大気中の二酸化炭素 (CO2) の変動が気候に影響する.
- 木の葉のストマトの頻度は,大気中のCO2と逆に相関する.
- 化石の葉は,過去のCO2レベルを再構築するための代理を提供しています.
研究 の 目的:
- 化石ベリーシの葉のストマト周波数を利用して,初期のホロセンの大気中のCO2濃度を再構築する.
- これらの再構築を既存の氷芯データと比較する.
主な方法:
- ホロセンの初期からの化石ベリーシの葉のストマタル周波数の分析.
- ストマタルとCO2の関係に基づいて,世紀規模のCO2変動の定量化.
主要な成果:
- 胃腔の周波数シグネチャーは,ホロセンの初期に突然のCO2増加を示した.
- その後のCO2の減少は,プレボレアル・オシレーションの冷却イベントと一致した.
- 初期のホロセンのCO2レベルは300ppmv以上と再構築され,氷の核の推定値とは対照的です.
結論:
- ストマタル周波数分析は,過去の大気中のCO2を評価するための信頼できる方法を提供します.
- 初期のホロセンの大気中のCO2濃度は,氷の核から先ほど推定されたよりも大幅に高かった.
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