在旧生代-新生代热量极限期间,热带上层海洋的氧气上升
Simone Moretti1,2, Alexandra Auderset1,3, Curtis Deutsch4
1Climate Geochemistry Department, Max Planck Institute for Chemistry, Mainz, Germany.
概括
全球变暖导致海洋缺氧, 但热带地区的氧气水平可能会上升. 在古世 - 世热极 (PETM) 期间,证据表明热带氧气增加,可能防止大规模灭绝.
科学领域:
- 古代海洋学
- 气候科学
- 海洋生物学
背景情况:
- 全球海洋的氧气正在减少,
- 在热带地区缺乏氧气的地区的未来仍然不确定.
- 古世 - 世热极值 (PETM) 为当前的变暖事件提供了有价值的类比.
研究的目的:
- 在PETM期间调查热带海洋氧化.
- 评估热带北太平洋缺氧区域对气候变暖的反应.
- 了解改变氧气水平对海洋生物的影响.
主要方法:
- 分析与菌结合的同位素以重建过去的氧气水平.
- 测量体大小作为氧气可用性的指标.
- 经验数据与海洋模型模拟的比较.
主要成果:
- 同位素表明在PETM期间北太平洋热带缺氧区域的收缩.
- 增加的体大小表明在浅层地下增加氧气的可用性.
- 海洋模型支持发现生物生产率下降可以在变暖期间增加热带地下氧气.
结论:
- 热带北太平洋在PETM期间经历了氧化,与全球脱氧趋势形成鲜明对比.
- 这种局部氧气增加可能减轻了大规模灭绝事件的严重性.
- PETM对未来可能对气候变化的海洋学反应提供了关键的见解.
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