衝突で発生した塵雲の環境への影響:白時代-三次期の絶滅への影響
Science (New York, N.Y.)
|January 21, 1983
まとめ
仮説的な衝突事故により,ゴミの雲が形成され,数ヶ月間,太陽光が著しく減少した. これは光合成と視界に影響を与え,地球温暖化と陸と海の大量絶滅を引き起こした.
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
- インパクトクレーター研究
- 大量絶滅の出来事 大量絶滅の出来事
背景:
- クレータ紀-三次紀 (K-T) の境界線は,重大な大量絶滅の出来事を示しています.
- 小惑星や彗星の衝突は,K-T絶滅の引き金であると仮定されています.
研究 の 目的:
- K-T衝突の破片雲の気候と放射線効果をモデル化するために.
- このような雲が地球表面の光と温度に与える潜在的影響を評価する.
主な方法:
- 瓦雲の進化と放射能の移転をシミュレートする数値モデルの開発.
- 光の減少と温度変化を決定するために,モデルの出力の分析.
主要な成果:
- 瓦の雲は,光合成レベルを下回る太陽光を数ヶ月間遮断していたかもしれない.
- 表面温度は,特に大陸 (最大40ケルビン) で著しく低下している可能性があります.
- 動物の視界は,より短い期間のために減少することができました.
結論:
- 海洋の絶滅は,光合成の停止によるものかもしれない.
- 陸上の絶滅は,光の減少と低温の組み合わせによって引き起こされた可能性が高い.
- 衝突によって引き起こされた破片雲は,大量絶滅の妥当なメカニズムを表しています.
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