Regionalnaya model dinamiki lda. Chast 2. Post-eksperimentalnaya obrabotka dannykh (in Russian: Regional ice-dynamic model. Part 2. Post-experimental processing of data)

摘要

In the paper we discuss a numerical experiment aiming at reconstruction of the ice-flow dynamics during the last 170 kyr around the drill site at Kohnen station, Dronning Maud Land, Antarctica. We focus at a 600×400 km nested domain of a regional model. The structure of the model and performance of the numerical experiment are described in detail in In the current research we employ a temperature record, which was reconstructed directly from the isotopical data derived from the Kohnen ice core, as a climatic forcing. Numerical experiment was carried out in several steps. On each step an innovation of forcing values was carried out. Non-climatic temperature biases were excluded from the forcing to derive pure climatic signal. These biases are explained by the local and by the upstream topographic effects.Post-processing of the experimental data was carried out by means of the Lagrangian backtracing method. Depth-age distribution in the ice core and places of origin of ice particles on the surface of the ice sheet were established. As a result of analysis of ice-particle trajectories, their velocities, and ice deformations we conclude that the flow was stable and that the stratigraphy of the upper 89%-layer was not disturbed.