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

South Dakota State University, Brookings SD

Investigators

Abstract

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 Greenland 2. 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 record 3. 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.