The µCT measurements are performed using the AWI-Ice-CT, a worldwide unique X-ray-microfocus computer tomograph operating in a cold lab. The setup, built in cooperation with Fraunhofer EZRT in 2009/10, allows very detailed 2D scans and 3D pore and ice structure reconstructions over whole ice core segments (length 1 m, diameter 10 cm). Resolutions of down to 2 µm are possible, however, due to the increasing measurement time, resolution is only chosen as small as necessary. The images are analyzed with a series of software tools and self-written scripts.
2D scans provide high quality density profiles. They are used for the reconstruction of density layering and the detection of melt features and wind crusts. Structure parameters like open and closed porosity, surface density, pore and ice intercept length, grain and pore size distributions, Euler number and coordination number are estimated from 3D volume images. Recent research topics are investigations of the temporal evolution of snow and firn characteristics in polar environments (Remote Sensing), studies of firn densification and air entrapment (Paleoclimate Research) and the reconstruction of ice deformation from bubble distributions in polar ice cores (The effect of deformation mechanisms for ice sheet dynamics).