Seasonal variations in the sources of natural and anthropogenic lead deposited at the East Rongbuk Glacier in the high-altitude Himalayas

• Published in: Science of The Total Environment
• Main Authors: Burn-Nunes, L, Vallelonga, P, Lee, K, Hong, S, Burton, G, Hou, S, Moy, AD, Edwards, R, Loss, R, Rosman, K
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier BV 2014
• Subjects: Earth Sciences; Physical Geography and Environmental Geoscience; Glaciology; Indian; ice core
• Online Access: https://doi.org/10.1016/j.scitotenv.2014.03.120; http://www.ncbi.nlm.nih.gov/pubmed/24797737; http://ecite.utas.edu.au/92300

Lead (Pb) isotopic compositions and concentrations, and barium (Ba) and indium (In) concentrations have been analysed at sub-annual resolution in three sections from a <. 110. m ice core dated to the 18th and 20th centuries, as well as snow pit samples dated to 2004/2005, recovered from the East Rongbuk Glacier in the high-altitude Himalayas. Ice core sections indicate that atmospheric chemistry prior to ~. 1953. was controlled by mineral dust inputs, with no discernible volcanic or anthropogenic contributions. Eighteenth century monsoon ice core chemistry is indicative of dominant contributions from local Himalayan sources; non-monsoon ice core chemistry is linked to contributions from local (Himalayan), regional (Indian/Thar Desert) and long-range (North Africa, Central Asia) sources. Twentieth century monsoon and non-monsoon ice core data demonstrate similar seasonal sources of mineral dust, however with a transition to less-radiogenic isotopic signatures that suggests local and regional climate/environmental change. The snow pit record demonstrates natural and anthropogenic contributions during both seasons, with increased anthropogenic influence during non-monsoon times. Monsoon anthropogenic inputs are most likely sourced to South/South-East Asia and/or India, whereas non-monsoon anthropogenic inputs are most likely sourced to India and Central Asia. 2014 Elsevier B.V.