パレオセンの終わりの気候温暖化のメカニズム
1Department of Earth Sciences, Oxford University, Parks Road, Oxford, OX1 3PR, UK. Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA.
Science (New York, N.Y.)
|July 31, 1999
まとめ
パレオセンの終わりの地球温暖化は,メタン水素脱ガスによって引き起こされた可能性がある. 複数のメタンの注入が地球の気候に影響を及ぼし,これらのイベントがグローバルなものであることを示唆する証拠があります.
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
- 地球科学 地球科学 地球科学
背景:
- パレオセーヌ・エオセーヌ熱最大期 (PETM) は,地球温暖化が急速な時期でした.
- この温暖化現象の正確なトリガーとメカニズムは,まだ議論されている.
- メタン水素は,温室効果ガスの潜在的な源である.
研究 の 目的:
- パレオセン・エオセンの温暖化現象におけるメタン水素脱ガス化の役割を調査する.
- 炭素と酸素のイソトープ記録を分析して,メタン放出の証拠を探します.
- 潜在的なメタン放出イベントの規模と頻度を決定する.
主な方法:
- 地質学的記録から得られた酸素と炭素の同位体比の分析.
- 地理的に異なる2つの場所からの同位体データの比較.
- 地球規模の気候現象を特定するための同位体シフトの相関.
主要な成果:
- アイソトープデータは,メタンの複数の明確な放出を示しています.
- これらのメタンの注入は,地球温暖化の時期と一致しました.
- 証拠によると,これらのイベントは地球規模で,世界中の気候に影響を与えました.
- メタンの放出イベントの間の炭素サイクル静止の間隔が観察されました.
結論:
- 生物学的メタン水素脱ガス化は,旧生代末期の急激な地球温暖化に重要な役割を果たした可能性が高い.
- データは,複数の,グローバルに同期されたメタン放出イベントのモデルをサポートします.
- これらの発見は,過去の気候動態と潜在的なフィードバックメカニズムについての理解を深める.
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