概括
由二氧化碳引起的全球变暖引发了中生代晚期的灭绝. 这一由温室条件驱动的古老事件,与现代气候变化与化石燃料燃烧等人类活动造成的气候变化相似.
科学领域:
- 古气候学 古气候学
- 古生物学的古生物学
- 地质化学 地质化学
背景情况:
- 中生代晚期以大规模灭绝结束,影响了海洋和陆地生物.
- 以前的研究表明,气候变化和这些灭绝事件之间存在潜在的联系.
研究的目的:
- 为了研究二氧化碳引起的全球变暖在晚期马斯特里希特灭绝中的作用.
- 分析气候趋势及其对中生代生态系统的影响.
主要方法:
- 对中生代晚期岩石和生命记录的分析.
- 从海洋微化石中解释氧同位素数据以重建过去的气候.
主要成果:
- 有证据表明,由于温室条件,在马斯特里希特纪晚期发生了短期的全球变暖 (10^510^6年).
- 氧同位素数据显示,在中马斯特里希特纪中期出现了冷却趋势,随后升温到中纪.
- 富含二氧化碳的水对海洋生物,特别是小型石灰质生物,产生了负面影响,影响了食物网.
结论:
- 降温后的突然变暖压倒了动物的适应能力,导致了灭绝.
- 深海二氧化碳的释放可能已经放大了变暖,创造了一个反循环.
- 现代人类活动,如化石燃料燃烧和森林砍伐,可能会复制这些过去的变暖条件.
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