Accumulation And Geochemical Evidence For The Little Ice Age Episode In Eastern Antarctica

Data on accumulation and concentration of chemical compounds recorded in an essentially unexplored area (Dome Argus ) of the Indian Ocean sector of eastern Antarctica during the past 2,680 years (680 B.C. to 1999 A.D.) are presented. During the first 1,700 years (680 B.C. to 1000 A.D.), the accumulation data shows a slightly decreasing trend, while chemical ions appear to be stable, representing a stable climatic condition. An intensive increasing trend of the accumulation occurred during the 12th to 14th century. The period from 15th to 19th century was characterized by a rapid reducing accumulation and concentrations of volatile compounds suffering post-depositional loss linked to sparse precipitation amount, which was temporally consistent with the Little Ice Age (LIA) episode. Comparison between observed accumulation rates with other eastern Antarctic ice cores show a consistent decreasing trend during LIA, while sea salt and dust-originated ions increased due to sea ice extent and intensified atmospheric transportation. Distribution of volcanic originated sulfate over the Antarctic continent show a significant change during the 15th century, coincident with the onset of the LIA. These results are important for the assessment of Antarctic continent mass balance and associated interpretation of the Dome A deep ice core records.