Past accumulation rates derived from observed annual layers in the GRIP ice core from Summit, central GreenlandIn Peltier, W.R., ed. Ice in the Climate System. Berlin Heidelberg: Springer-Verlag, 517-532., 1993.
D. Dahl-Jensen, S.J. Johnsen, C.U. Hammer and H.B. Clausen
Geofysisk Afdeling, Niels Bohr Instituttet for Astronomi, Fysik og Geofysik, Københavns Universitet
Based on dated reference horizons down to 1623 m an ice flow model has been developed. The model is used to reconstruct past accumulation rates from the sequences of detected annual layers in the upper 2321 m of the 3029 m deep GRIP ice core. Comparison of these past time accumulation rates with the corresponding delta180 values show a strong correlation. This relationship can be used in a non steady state flow model, in which past accumulation rates, deduced from the continuous delta180 record, are used to model a time scale. The hereby determined time scale and the modelled annual layers compare well with the observed data.