| Summary: | Recent model calculations have attempted to quantify the contribution ofmajor energetic solar cosmic ray (SCR) events to 10 Be production. In thisstudy we compare modeled 10 Be production by SCR events to measured 10 Be concentrations in a Law Dome snow pit record. The snow pit recordspans 2.7 years, providing a quasi-monthly 10 Be sampling resolution whichoverlaps with the SCR events of 29 Oct 2003 and 20 Jan 2005. Theseevents were calculated to increase monthly 10 Be production in the polaratmosphere (>65 S geomagnetic latitude) by ~60% and ~120% above theGCR background, respectively. A strong peak in 10 Be concentrations (>4Ďabove the 2.7 y mean value) was observed ~1 month after the 20 Jan 2005event. By contrast, no signal in 10 Be concentrations was observed followingthe weaker 29 Oct 2003 series of events. The concentration of 10 Be in icecore records involves interplay between production, transport, and depositionprocesses. We used a particle dispersion model to assess vertical and meridionaltransport of aerosols from the lower stratosphere where SCR production of 10 Be is expected to occur, to the troposphere from where deposition to the icesheet occurs. Model results suggested that a coherent SCR production signalcould be transported to the troposphere within weeks to months following bothSCR events. We argue that only the 20 Jan 2005 SCR event was observedin measured concentrations due to favorable atmospheric transport, relativelyhigh production yield compared to the 29 Oct 2003 event, and a relatively highlevel of precipitation in the Law Dome region in the month following the event.This result encourages further examination of SCR signals in 10 Be ice core data.
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