Assessment of the natural perchlorate source using perchlorate history from Greenland ice cores.

高氯酸盐是一种长寿的环境污染物，从人类活动中释放出来，但越来越多地被认为也有自然来源。调查人员提议测量以前收集的格陵兰冰芯中的高氯酸盐，具体目标如下：1.使用格陵兰冰芯样本获得环境中高氯酸盐的可靠(连续和年度分辨率)记录2。利用记录中1850年前的部分，量化北半球环境中自然的、可能是大气中的高氯酸盐来源的大小和可变性3。评估自然和人为来源在当前环境中对高氯酸盐的相对贡献，以及4.通过仔细检查特定时间段(例如1950年代之前和之后)的高氯酸盐记录来评估特定人类活动(例如空间应用)的影响。该项目将涉及应用一种新方法来测量极地冰中极低浓度的高氯酸盐。实现这一主要目标可以提高我们对环境重要物质自然形成过程的理解。这项工作的结果可能会为有关高氯酸盐释放到环境中的监管决策提供参考。该项目将涉及研究生和本科生参与者，并为南达科他州州立大学和南达科他州K-12学校之间的环境推广计划做出贡献。

Perchlorate is a long-lived environmental contaminant, released from human activities but increasingly recognized to have a natural source as well. The investigators propose to measure perchlorate in previously-collected Greenland ice cores, with the following specific objectives:1. To obtain a robust (continuous and annual resolution) 500-year record of perchlorate in the environment using ice core samples from Greenland2. To quantify the magnitude and variability of the natural, probably atmospheric perchlorate source in the Northern Hemisphere environment using the pre-1850 part of the record3. To estimate the relative contributions of natural and anthropogenic sources to perchlorate in the current environment, and 4. To evaluate the impact of specific human activities (e.g., space applications) by a close examination of the perchlorate record during specific time periods (e.g., pre- and post-1950s).The project will involve the application of a new method to measure extremely low concentrations of perchlorate in polar ice. Achievement of the main objective can lead to improvement of our understanding of the natural formation process of environmentally important substances. Results of this work may inform decision-making regarding the regulation of perchlorate release into the environment. The project will involve both graduate and undergraduate student participants and contribute to an environmental outreach program between South Dakota State University and K-12 schools in South Dakota.