Through time, the Greenland Ice Sheet has waxed and waned with the changes in climate. Snow deposited on the surface is gradually turned into ice and moves down and towards the edges of the ice sheet. Today, the ice sheet holds ice deposited during the last glacial cycle, i.e. the last ~100,000 years. By drilling and analyzing ice cores from the Greenland Ice Sheet, it is thus possible to study the climate and the ice sheet conditions during this period. The climate records thus obtained have unique temporal resolution. The deeper down through the ice sheet you go, the older the ice gets, but the exact relationship between depth and age in an ice core differs between locations due to differences in e.g. the amount of snowfall, ice thickness, basal melt rate and ice flow pattern. Several deep ice cores from Greenland have been drilled and analyzed.
In this project, we will focus on the deepest ice cores from GRIP, NGRIP and GISP2. If time allows, data from NEEM and/or Dye-3 could be included as well. We intend to use simple 1D mathematical models of how the ice moves down through the ice sheet to investigate the observed differences in the depth-age relationships in multiple deep ice cores. The models will be constrained by the observed depth-age relationship from the ice cores and used to investigate the possibility of changes in factors like accumulation rate, ice thickness, ice flow or basal properties constituting a possible explanation for the observed differences between the ice-core depth-age relationships, and thus contribute to our general understanding of how the Greenland Ice Sheet reacts to changes in climate and changes in ice dynamics.