氷の核からの脱氷によるCO2上昇に対する炭素同位体制約は,氷の核からの脱氷によるCO2上昇に影響する
Jochen Schmitt1, Robert Schneider, Joachim Elsig
1Climate and Environmental Physics, Physics Institute, and Oeschger Centre for Climate Change Research, University of Bern, CH-3012 Bern, Switzerland. schmitt@climate.unibe.ch
まとめ
大気中の二酸化炭素 (CO2) の安定した炭素同位体比は,過去の炭素サイクルシフトを明らかにします. 初期の脱氷期には,南洋の上流と関連したCO2イソトープの減少があり,その後の変化は生物圏と海洋動態によって引き起こされた.
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
- 地質化学 地質化学
- 地球システム科学 地球システム科学
背景:
- 大気中のCO2 (δ(13) C(atm)) の安定した炭素同位体比は,過去の炭素循環の動態を理解するために重要である.
- δ ((13) C ((atm) を再構築すると,世界の炭素貯蔵庫とフローの洞察が得られます.
研究 の 目的:
- 過去2万4000年間をカバーする新しい δ (((13) C (((atm) データを提示する.
- 最後の氷河期と氷河期間の移行期における大気中のCO2イソトープ変化の要因を調査する.
主な方法:
- 3つの独立した記録から得られた δ(13) C(atm) の分析.
- 2つの南極の氷の核からのデータを活用して.
主要な成果:
- 初期の脱氷期において,δ(13) C(atm) の1ミリあたり0.3分の1の有意な減少.
- 初期の脱氷の主要な原因として,古い,炭素濃縮された水の南洋の上流の識別 δ (((13) C (((atm) 減少.
- 陸上の生物圏の再生,海面温度,海洋循環が,後の脱氷期 δ (((13) C (((atm) の進化に影響を与えたことを示す.
- 最後の氷河期最大期における常数 δ (((13) C (((atm) と CO (((2) の観測により,炭素循環の均衡が示された.
結論:
- 南洋の過程は,初期の脱氷期の炭素循環の変化に重要な役割を果たしました.
- 陸上の生物圏と海洋のダイナミクスは,脱氷後の大気中のCO2イソトープを調節した.
- 最後の氷河期最大期の間,炭素循環はダイナミックな均衡状態にあり,以前は深海で炭素を吸収していた.
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