パレオセーヌ・エオセーヌ熱マキシマム中,主に火山による炭素の非常に大きな放出
Marcus Gutjahr1,2, Andy Ridgwell3,4, Philip F Sexton5
1Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Southampton SO17 1BJ, UK.
Nature
|September 1, 2017
まとめ
メタン水素ではなく,火山活動が,旧生代・新生代 (PETM) の地球温暖化現象を誘発した可能性が高い. 大量の炭素が放出され 地球の気候と海洋の化学的構造が変わりました
科学分野:
- 古代気候学
- 地化学
- 地球システム科学
背景:
- パレオセノ・エオセノ熱極 (PETM) は,地球温暖化に関する重要な出来事である.
- PETMの主な原動力は,表面の炭素貯蔵庫であろうと,他の源であろうと,依然として議論されている.
- PETMの原因を理解することは 気候変動の研究にとって極めて重要です
研究 の 目的:
- PETMの原因となる 炭素の源を調べる
- この古代の温暖化現象の 炭素循環のダイナミクスを再構築します
- 気候現象のトリガーメカニズムとフィードバックプロセスを区別する.
主な方法:
- 海水pHのプロキシとして,ボロン同位体の分析.
- 炭素同位体記録とpHデータを統合する
- 炭素循環のダイナミクスをシミュレートするために地球システムモデルを使用します.
主要な成果:
- 持続的な低海面pHは,PETMの間に記録されました.
- 証拠によると,以前見積もっていたよりも,かなり大きい (Pg10,000以上) 且つ,同位体的に重い炭素源があることが示唆されている.
- 北大西洋火山地帯に関連した火山活動が主な要因とされています.
結論:
- メタン水素ではなく 火山活動がPETMの主な原動力でした
- 気候変動による有機炭素のフィードバックは イベントの開始に小さな役割を果たしました
- 強化された有機物質の埋葬は 炭素を閉じ込め 地球システムの回復を促進する鍵でした
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