HR: 08:00h
AN: U41B-01    [Abstracts]
TI: Modeling Be-10 in Polar ice: Climatic vs. Solar Effects
AU: * Field, C V
EM: cfield@giss.nasa.gov
AF: NASA Goddard Institute for Space Studies, Columbia University, 2880 Broadway, New York, NY 10025 United States
AU: Schmidt, G A
EM: gschmidt@giss.nasa.gov
AF: NASA Goddard Institute for Space Studies, Columbia University, 2880 Broadway, New York, NY 10025 United States
AU: Schmidt, G A
EM: gschmidt@giss.nasa.gov
AF: Center for Climate Systems Research, 2880 Broadway, New York, NY 10025 United States
AU: Koch, D
EM: dkoch@giss.nasa.gov
AF: NASA Goddard Institute for Space Studies, Columbia University, 2880 Broadway, New York, NY 10025 United States
AU: Koch, D
EM: dkoch@giss.nasa.gov
AF: Center for Climate Systems Research, 2880 Broadway, New York, NY 10025 United States
AB: The close correlation between the production of the cosmogenic isotope $^{10}$Be and changes in heliomagnetic activity makes ice-core $^{10}$Be an attractive proxy for studying changes in solar output. However, the task of interpreting $^{10}$Be ice-core records on centennial timescales is complicated by the fact that climate-related deposition changes -- which may be unrelated or disproportional to variations in irradiance -- can potentially obscure $^{10}$Be's solar production signal. By using the GISS ModelE GCM to selectively vary climate and production functions, we model $^{10}$Be flux values and then calculate concentration changes at key coring sites. We will present results for solar changes and compare them to variations in $^{10}$Be concentration as functions of (a) ocean changes related to the 8.2 ky event and (b) atmospheric changes due to varying volcanic and greenhouse gas forcings.
DE: 9310 Antarctica
DE: 9315 Arctic region
DE: 3309 Climatology (1620)
DE: 1650 Solar variability
DE: 0305 Aerosols and particles (0345, 4801)
SC: Union [U]
MN: 2004 AGU Fall Meeting