BERYLLIUM-10 CONCENTRATIONS IN THE GREENLAND ICE-SHEET PROJECT-2 ICE CORE FROM 3-40 KA

A nearly continuous record of Be-10 (half-life of 1.5 x 10(6) years) c oncentrations is reported in the Greenland Ice Sheet Project 2 (GISP2) ice core for the time period between 3288 and 40,055 years B.P. The r esolution is between 20 and 50 years in the Holocene. During the Pleis tocene, sampling was coarser, with the resolution ranging between 50 a nd 200 years. Both concentrations and fluxes are reported. Concentrati ons of Be-10 are observed to correlate strongly with delta(18)O and mo re weakly with snow accumulation rates. Beryllium 10 fluxes show less dependence than do concentrations on climate-related parameters. A goo d correlation exists between Delta(14)C and Be-10 for centennial scale variations, which are most likely due to heliomagnetic modulation of the lone production rate in the atmosphere. There is no evidence of a long-term geomagnetic effect on the Be-10 flux at GISP2. The interpret ation of the record depends strongly on the model one uses to infer at mospheric Be-10 concentrations' from the measured concentrations in sn ow.