在过去25万年中,地中海西部的突然温度变化
Belen Martrat1, Joan O Grimalt, Constancia Lopez-Martinez
1Department of Environmental Chemistry Institut d'Investigacions Quimiques i Ambientals de Barcelona-Consell Superior d'Investigacions Cientifiques (CSIC), 08034-Barcelona, Spain.
Science (New York, N.Y.)
|December 4, 2004
概括
西地中海的海面温度突然变化 (SST) 在过去25万年的变暖期间更为频繁. 与冷却时期相比,这些变暖事件显示出更大的强度和更快的变化速度.
科学领域:
- 古气候学 古气候学
- 海洋地球化学 海洋地球化学
- 季度气候动力学 四季度气候动力学
背景情况:
- 了解过去的气候变化对于预测未来的气候变化至关重要.
- 西地中海是研究气候动态的一个关键地区,因为它对各种气候强迫的敏感性.
- 基于基的海面温度 (SST) 记录提供了对过去海洋条件的高分辨率洞察力.
研究的目的:
- 为了重建过去25万年来西地中海的高分辨率SST记录.
- 研究不同气候状态期间突然气候变化的频率,强度和速度.
- 为了比较不同海洋同位素阶段 (MIS) 之间的突然气候变化模式.
主要方法:
- 对来自西地中海的连续高分辨率基衍生SST记录的分析.
- 对过去25万年的古气候数据进行检查,包括海洋同位素阶段.
- 在升温和降温阶段以及在不同MIS之间比较SST变化模式.
主要成果:
- 发现突然的SST变化在变暖时期比降温期间更常见.
- 在MIS 6期间,SST振荡呈现出阶段-阶段间的模式,但强度较低,变化速度比MIS 3Dansgaard/Oeschger事件慢.
- 在MIS 5和MIS 7期间观察到的最显著的突然气候事件是长期稳定,温暖的间冰期条件之后.
结论:
- 在过去25万年中,西地中海地区经历了更频繁的突然变暖事件.
- 在冰河间时期的气候稳定性可能会先于更明显的气候突然变化.
- 该研究强调了与其他古气候记录相比,突然气候变化动态的区域差异.
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