The similar timing and magnitude of changes in lead deposition across Antarctica, as well as the characteristic isotopic signature of Broken Hill lead found throughout the continent, suggest that this single emission source in southern Australia was responsible for the introduction of lead pollution into Antarctica at the end of the 19th century and remains a significant source today, the authors report.
This study included ice cores collected as part of projects funded by the U.S. National Science Foundation. Additional ice cores were contributed to the study by international collaborators including the British Antarctic Survey, the Australian Antarctic Division, and the Alfred Wegener Institute in Germany.
"The ice cores obtained through international collaborations were critical to the success of this study in that they allowed us to develop records from parts of Antarctica not often visited by U.S.-based scientists," said co-author Tom Neumann of NASA's Goddard Space Flight Center. "This included the Law Dome region of East Antarctica and a big section of East Antarctica visited by the Norwegian-United States Scientific Traverse of East Antarctica."
McConnell explained the hazards of working in such extreme environments. "I remember the day in 1999 we drilled the shallow core about 15 km from South Pole. The temperature was negative 100 degrees Fahrenheit with the wind chill so it was hard to motivate the field team to leave the galley at the South Pole station that day, he said."
Data from the new ice core array illustrates that Antarctic lead concentrations reached a peak in
|Contact: Justin Broglio|
Desert Research Institute