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环境和气候变化前沿学术论坛系列报告

报告地点:理化大楼12007

报告时间:星期三,2019-06-19 10:30 - 11:30

报告人:Dr. Jihong Cole-Dai(戴际宏)

报告人简介:

Jihong Cole-Dai(戴际宏),美国南达科他州立大学(South Dakota State University)化学和生物化学系教授,冰芯化学和火山活动研究专家。1982年毕业于中国科技大学化学系, 1987年获美国马里兰大学分析和环境化学博士学位,1988-1999年在俄亥俄州立大学的伯德极地研究中心任职参与冰芯研究。长期从事极地考察、大气化学反应机理、冰芯挖掘与分析、气候变化等交叉学科的研究工作,利用冰芯记录提供了第一个完备的过去4000多年的火山活动记录,在Science,JGR,EST等国际期刊发表论文40余篇。参与了美国WAIS Divide deep ice core以及 South Pole Ice Core 等重要冰芯计划并作出了重要贡献。

报告题目:Perchlorate Records from Polar Ice Cores: Impact of Human Activities and Volcanic Eruptions.

报告内容简介

A 300-year record of environmental perchlorate, reconstructed from high- resolution analysis of a central Greenland ice core, shows that perchlorate levels in the post-1980 atmosphere were two-to-three times those of the pre-1980 environment. The record demonstrates that the Industrial Revolution and other human activities, which emitted large quantities of pollutants and contaminants, did not significantly impact environmental perchlorate, as perchlorate levels remained stable throughout the eighteenth, nineteenth, and much of the twentieth centuries. The increased levels since 1980 likely result from enhanced atmospheric perchlorate production.  The enhancement is probably influenced by the emission of organic chlorine compounds in the last several decades.  Brief (a few years) high concentration episodes appear frequently over an apparently stable and low background (~1 ng kg‒1).  Several such episodes coincide in time with large explosive volcanic eruptions including the 1912 Novarupta/Katmai eruption in Alaska. It appears that atmospheric perchlorate production is impacted by large eruptions in both high and low latitudes.