自公元前7000年以来的火山活动记录 来自GISP2格陵兰冰芯和对火山气候系统的影响
Science (New York, N.Y.)
|May 13, 1994
概括
格陵兰岛的冰芯揭示了大约公元前5000-7000年早期的火山活动. 这一时期出现了硫酸盐沉积的增加,可能导致气候变冷.
科学领域:
- 古气候学 古气候学
- 火山学 火山学是一门学科.
- 冰川学的冰川学
背景情况:
- 冰芯,例如格陵兰岛的GISP2核心,提供了过去大气条件的宝贵档案.
- 冰芯中的硫酸盐度作为火山活动和潜在的气候强迫的代理.
- 了解过去的火山事件对于重建气候历史至关重要.
研究的目的:
- 从GISP2格陵兰冰核中使用硫酸盐度重建潜在气候强迫火山活动的记录.
- 为了比较 Holocene 早期火山事件的频率和规模与过去两千年.
主要方法:
- 持续的两年一次的GISP2格陵兰冰芯采样.
- 对硫酸盐度的分析,以确定火山爆发标志物.
- 将日期的硫酸盐事件与记录的历史火山爆发相匹配.
主要成果:
- 记录了大量的硫酸盐事件,特别是在公元前5000年至7000年之间.
- 虽然85%的近期事件 (过去2000年) 与记录的喷发相匹配,但只有30%的早期Holocene事件.
- 早期的Holocene火山事件显示硫酸盐沉积量是已知的最大历史喷发的1-5倍,其频率是已知的最大历史喷发的3倍.
结论:
- 早期的Holocene经历了比以前估计的要高得多的火山活动.
- 这种增加的火山活动可能在早期Holocene气候冷却中发挥了重要作用.
- 一些历史上的喷发可能是比目前公认的更具影响力的硫生产者.
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