200-year ice core bromine reconstruction at Dome C (Antarctica): observational and modelling results

• Published in: The Cryosphere
• Main Authors: F. Burgay, R. P. Fernández, D. Segato, C. Turetta, C. S. Blaszczak-Boxe, R. H. Rhodes, C. Scarchilli, V. Ciardini, C. Barbante, A. Saiz-Lopez, A. Spolaor
• Format: Article in Journal/Newspaper
• Language: English
• Published: Copernicus Publications 2023
• Subjects: Environmental sciences; GE1-350; Geology; QE1-996.5; Antarctic; The Antarctic; East Antarctica; Antarc*; Antarctica; ice core; Sea ice; The Cryosphere
• Online Access: https://doi.org/10.5194/tc-17-391-2023; https://doaj.org/article/8317d124e484495bb98af4b6743f3311

Bromine enrichment (Br enr ) has been proposed as an ice core proxy for past sea-ice reconstruction. Understanding the processes that influence bromine preservation in the ice is crucial to achieve a reliable interpretation of ice core signals and to potentially relate them to past sea-ice variability. Here, we present a 210 years bromine record that sheds light on the main processes controlling bromine preservation in the snow and ice at Dome C, East Antarctic plateau. Using observations alongside a modelling approach, we demonstrate that the bromine signal is preserved at Dome C and it is not affected by the strong variations in ultraviolet radiation reaching the Antarctic plateau due to the stratospheric ozone hole. Based on this, we investigate whether the Dome C Br enr record can be used as an effective tracer of past Antarctic sea ice. Due to the limited time window covered by satellite measurements and the low sea-ice variability observed during the last 30 years in East Antarctica, we cannot fully validate Br enr as an effective proxy for past sea-ice reconstructions at Dome C.