[MIS15-P24] East Antarctic meltwater influx from the Wilkes Subglacial Basin since the Last Glacial Maximum as determined by beryllium isotopes
Keywords:East Antarctica, beryllium isotopes, Holocene, ice sheet instability, Wilkes Subglacial Basin
To investigate the response of these vulnerable areas to a warming ocean and atmosphere, we have evaluated beryllium isotope concentrations from Adélie Basin, located on the continental shelf offshore the Wilkes Subglacial Basin. Our record covers the most recent period of major Holocene ice sheet retreat, sea level rise, and increased atmospheric CO2since the Last Glacial Maximum ice sheet retreat (5). The beryllium isotope data suggest oceanic or climatic changes occurred at ca. 9.8 ka, ca. 6.3 ka, and from ca. 4.1 ka. From prior research, we can conclude our high meteoric 10Be values at ~9.8 ka and ~6.3 ka are attributed to an open marine environment created by the retreat of grounded ice along with an increased influx of meltwater (6-8). The elevated concentration and frequency variation of meteoric 10Be values starting from ~4.1 ka indicates a change in regime, possibly linked to changes in climate.
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