全球气候的趋势,节奏和异常 65 Ma 呈现
1Earth Sciences Department, University of California, Santa Cruz, CA 95064, USA. jzachos@es.ucsc.edu
概括
地球的气候在6500万年里发生了显著的变化,新的深海核心数据揭示了复杂的变暖,冷却和快速变化. 这项研究阐明了中生代气候变化及其驱动机制.
科学领域:
- 古气候学 古气候学
- 地质地质地质地质地质地
- 气候科学 气候科学
背景情况:
- 地球的气候在过去6500万年 (Ma) 里发生了显著的变化.
- 深海沉积物核心为了解过去的气候变化提供了关键数据.
- 气候演变包括渐进的趋势,周期性循环和突然的变化.
研究的目的:
- 审查最近在定义全球气候演变的进步,在中生时代.
- 专注于在早期的代时期周期性和异常的气候变化.
- 确定以前未知的气候变化机制.
主要方法:
- 深海同位素记录的分析.
- 对古气候代理物的沉积物核心的研究.
- 检查构造学和轨道强迫机制.
主要成果:
- 详细描述中生纪气候演变的特征,包括变暖和变冷趋势.
- 确定周期性周期 (10^410^6年) 和快速气候过渡 (10^310^5年).
- 更好地了解由构造和轨道过程驱动的气候变化.
结论:
- 深海记录提供了对中世纪气候动态的高分辨率洞察.
- 这项研究强调了推动气候变化的因素的复杂相互作用.
- 从最近的研究中,对气候变化机制的新观点已经出现.
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