地球の脱ガス:エタンとプロパンのソースが欠けている.
Giuseppe Etiope1, Paolo Ciccioli
1Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma 2, via V. Murata 605, 00143 Rome, Italy. Etiope@ingv.it
まとめ
地熱や火山地帯を含む自然地質学的浸出は,大気中のエタンとプロパンの大量発生源である. 地球の排気は,エタンの少なくとも17%,プロパンの10%の排出量を占め,世界の予算のバランスをとるのに役立ちます.
科学分野:
- 地化学と大気科学
背景:
- エタン (C2H6) の世界の大気予算は不均衡であり,欠けている源を示しています.
- 現在の排出量インベントリは,大気中の炭化水素のすべての源を完全に考慮していない.
研究 の 目的:
- 大気中のエタンの予算に寄与する"未知"の源を特定する.
- 大気中のエタンおよびプロパン (C3H8) 濃度に対する天然地質学的浸透の寄与を定量化するために.
主な方法:
- 238の異なる地理的・地質的な場所からの地表ガス排出におけるメタン (CH4),エタン,プロパン濃度の分析.
- 公開されたジオメタン排出量の推定値の統合.
主要な成果:
- 石油,地熱,火山地帯からの天然ガスの漏れは,実質的に欠けている源として特定されています.
- 地球の排気は,エタンの総排出量の少なくとも17%を占めています.
- 地球の排気は,プロパンガス排出量の少なくとも10%を占めています.
結論:
- 地質学的源は,エタンとプロパンの世界の大気予算に重要な役割を果たしています.
- 天然ガスの漏れは,大気中の炭化水素濃度の主要な要因であり,現在の排出量在庫の不一致を解決するのに役立ちます.
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