晩四年期の二酸化炭素濃度の炭素同位体記録である
1Department of Geological Sciences, Indiana University, Bloomington 47405-5101, USA.
Nature
|October 4, 1990
まとめ
大気中の二酸化炭素 (CO2) レベルは,地球の最後の氷河期と氷河期間の移行期の間に著しく上昇した. この研究は,過去CO2の変化を追跡するために堆積物核イソトープを使用する方法を明らかにし,私たちの気候記録をさらに遡ります.
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
- 地質化学 地質化学
- 海洋学 海洋学とは
背景:
- 大気中のCO2は,最後の氷河期と氷河間期の間に180ppmから280ppmに増加した.
- この大気の変化は,海洋の混合層の溶けたCO2の増加によって引き起こされた.
- 光合成は,溶けたCO2を有機物質の炭素同位体組成と結びつける.
研究 の 目的:
- 大気中のCO2と海洋有機物質の炭素同位体との関係を調査する.
- 過去の大気中のCO2レベルを堆積物核から再構築するためのプロキシを確立する.
- 堆積物のイソトープ記録を,既存の氷芯のCO2データと相関させるため.
主な方法:
- 氷床に閉じ込められたガスの分析により,過去の大気中のCO2濃度が決定される.
- ヘミペラジック堆積物の中核における炭素同位体組成 (13C) の検査.
- 堆積物核の同位体記録と,ヴォストークの氷核のCO2記録の相関.
主要な成果:
- 大気中のCO2レベルを反映する信号が,堆積物核の同位体記録で特定されました.
- この信号は,ヴォストークの氷の核から得られたCO2記録と相関させられた.
- この研究は,炭素同位体の分断と大気中のCO2濃度との関連性を示しています.
結論:
- 海洋堆積物における炭素同位体記録は,大気中のCO2の代理として機能することができます.
- この方法は,氷のコアの記録の時間枠を超えたCO2レベルを再構築することを可能にします.
- 更に校正することで,古気候 CO2 の再構築を,以前の地質学期まで延長することができます.
キーワード:
NASAの規律 エキゾバイオロジーNASAの規範番号52-30は,NASAの規範番号52-30は,NASAの規範番号52-30は,NASAの規範番号52-30は,NASAの規範番号52-30は,NASAの規範番号52-30は,NASAの規範番号52-30は,NASAの規範番号52-30は,NASAの規範番号52-30は,NASAの規範番号52-30は,NASAの規律番号52-30は,NASAの規律番号52-30は,NASAの規律番号52-30は,NASAの規律番号52-30は,NASAの規律番号52-30は,NASAの規律番号52-30は,NASAの規律番号52-30はNASA エクゾバイオロジープログラム非NASAのセンターです.関連する概念動画
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