百年级的全新世气候变化,由来自爱尔兰西南部的高分辨率洞穴三角洲18O记录揭示
F McDermott1, D P Mattey, C Hawkesworth
1Department of Geology, University College Dublin, Dublin 4, Ireland.
Science (New York, N.Y.)
|November 10, 2001
概括
格陵兰岛冰核中的全新纪气候变化是理解未来变暖的关键. 一个来自爱尔兰的洞穴记录显示了区域气候的一致性,揭示了早期Holocene冷却事件.
科学领域:
- 古气候学 古气候学
- 同位素地球化学 同位素地球化学
- 四分学科学 四分学科学
背景情况:
- 了解全新纪气候变化对于预测未来人类造成的变暖影响至关重要.
- 格陵兰岛的冰芯提供了关键的,高分辨率的古气候档案.
- 冰核中的亚千年级氧同位素 (delta18O) 波动反映了过去的气候动态.
研究的目的:
- 评估格陵兰岛冰芯中Holocene亚千年delta18O变化的重要性.
- 通过比较爱尔兰洞穴记录与格陵兰冰芯数据来调查区域气候的一致性.
- 为了确定潜在的早期Holocene冷却事件,并评估北大西洋冰上漂流的影响.
主要方法:
- 来自爱尔兰西南部的一个洞穴生物的高分辨率氧同位素 (delta18O) 分析.
- 洞穴delta18O记录与格陵兰冰芯delta18O数据的相关性.
- 对百年级气候变化和冰上漂流证据的分析.
主要成果:
- 斯佩雷瑟姆的delta18O变化与格陵兰冰芯的delta18O变化相关,这表明早期的Holocene区域气候一致性.
- 确定了以前未被发现的早期Holocene冷却事件的证据.
- 北大西洋冰上漂流在Holocene中期到晚期对爱尔兰洞穴动物的delta18O记录产生了很小的影响.
结论:
- 斯皮勒奥塞姆记录为区域气候动态提供了有价值的见解,补充了冰芯数据.
- 早期的全新纪气候表现出显著的百年级变化和区域连贯性.
- 与冰芯记录相比,海洋边缘地点可能对北大西洋冰上漂流事件的反应有所减弱.
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