在夏季,上层海洋分层和混合层深度增加
Jean-Baptiste Sallée1, Violaine Pellichero2,3, Camille Akhoudas4
1Sorbonne Université, CNRS/IRD/MNHN, LOCEAN, IPSL, Paris, France. jean-baptiste.sallee@locean-ipsl.upmc.fr.
Nature
|March 25, 2021
概括
海洋变暖正在增加上层海洋的稳定性, 这项研究揭示了世界上层海洋在五十年中的重大变化.
科学领域:
- 海洋学
- 气候科学
- 海洋生态系统
背景情况:
- 海洋表面混合层对于通过热量和碳交换调节全球气候至关重要.
- 它还支持海洋生态系统和氧化深海层.
- 由于气候变化而造成的混合层变化尚未得到充分了解.
研究的目的:
- 研究海洋混合层的深度和稳定性的变化.
- 通过海洋观测分析1970年至2018年的趋势.
- 了解海洋初级生产和海洋动态的影响.
主要方法:
- 利用了1970年至2018年的海洋观测.
- 应用了基于物理的上海稳定性的定义.
- 分析了全球海洋系统中密度对比和混合层深度的趋势.
主要成果:
- 混合层基础上的密度对比度显著增加 (每十年8.9±2.7%).
- 与预期相反,混合层深化 (每十年2.9±0.5%,或每十年5-10米).
- 同时的分层和深化与表面变暖,清新和加剧的流有关.
结论:
- 这项研究揭示了以前被低估的世界上层海洋变化.
- 这些发现挑战了先前关于混合层稀释与增加分层的假设.
- 结果需要重新评估影响海洋初级生产和海洋生态系统的驱动因素.
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