地球の初期の大気圏における水素-窒素温室効果温暖化
Robin Wordsworth1, Raymond Pierrehumbert
1Department of Geological Sciences, University of Chicago, Chicago, IL 60637, USA. rwordsworth@uchicago.edu
まとめ
初期の地球は,二酸化炭素だけでなく,水素と窒素 (H2−N2−) の相互作用によって暖かくなっていたのかもしれません. この大気温暖化により,太陽光線が低いにもかかわらず,液体の水が存在し,初期の微生物による潜在的な冷却効果があった.
科学分野:
- 惑星科学 惑星科学
- 気候科学 気候科学
- 地質科学は地質科学である.
背景:
- 地球の初期の歴史はパラドックスを提示しています:太陽の明るさが低く,表面液体の水が持続しています.
- 居住可能な温度を維持するメカニズムを理解することは,惑星の進化の研究にとって極めて重要です.
研究 の 目的:
- 初期の地球温暖化における水素-窒素 (H(2) -N(2)) 衝突による吸収の役割を調査する.
- H2−N2の温暖化とCO2の濃度が合わさって,太陽光流量が減少した状態で液体の水を維持できるかどうかを判断する.
主な方法:
- H(2) -N(2) の衝突誘発吸収を組み込んだ大気モデリング.
- 異なる大気組成と太陽の流れを持つ初期の地球の気候条件のシミュレーション.
主要な成果:
- H(2) -N(2) 衝突による吸収は,最近の大気圧制と一致して,初期の地球を著しく暖めた.
- 2〜3倍のN2質量と0.1のH2混合比率で,太陽の75%の流れの下で,温度を0°C以上維持するのに十分な温暖化が発生します.
- この温暖化は,CO2のレベルが現在の値の2~25倍である場合にのみ達成可能である.
結論:
- 水素-窒素の相互作用は,初期の地球の持続的な液体の水のための実行可能なメカニズムを提供します.
- 初期のメタノゲン生物は,H (−2) とCO (−2) をメタン (CH (−4)) に変換し,地質学的証拠を残し,気候に影響を及ぼした可能性がある.
関連する概念動画
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