Heavy metal concentrations and isotope ratios in Law Dome snow as indicators of recent climatic and environmental variability

Project aim

The widespread use of lead since antiquity has left an indelible mark on the Northern Hemisphere polar ice archives in Greenland. Using its isotopes this lead was traced to emissions from early Roman mining and smelting operations in southern Spain. Measurements of more recent snow have also identified lead contributions from North America and Eurasia and show that the decline that began in the 1970s was primarily due to the removal of Pb from petrol in the United States. We know now, from very recent measurements on the Antarctic ice archive, that the Southern Hemisphere has experienced quite a different lead pollution history but the record is incomplete. This study aims to fully document changes that have occurred in the snow during the last decade at Law Dome. An approach similar to that used in the Northern Hemisphere will then be used to identify the sources of pollution reaching this part of the Australian Antarctic Territory.