Large amplitude solar modulation cycles of 10Be in Antarctica: Implications for atmospheric mixing processes and interpretation of the ice core record

Abstract

10Be concentrations in an ice core at Taylor Dome, Antarctica show greater variation over the last 75 years than similar 10Be time‐series from Greenland. Like the Greenland records, the new Antarctic data exhibit a strong periodicity which follows expected changes in the production rate of 10Be over the 11‐year solar cycle. Noting that the amplitude of production‐rate variation is both latitude and altitude dependent, we estimate the relative contribution of 10Be from different atmospheric reservoirs. The calculations yield a relatively small (<35%) contribution from the low‐to‐mid latitude stratosphere, suggesting a weak coupling between Antarctic 10Be and geomagnetic field intensity.