As a comparison surface processes are examined in a similar way using the top layers in the snow and looking at the atmospheric interactions for the past three or four years. The gases from the three-year cores are correlated with the automatic weather station data. Looking at each layer for the three years is important also. This information is used to determine how to interpret the gases from the deep ice cores. Other gaseous compounds found in the cores such as sulfur based or other acids can be linked to volcanic events in the past.
Scientists look at fabric of the ice as part of ice dynamics.
By this they mean that they are looking at the orientation of the ice crystals within the cores using a polarizing lens. Physics students will be able to explain how this works. When all the crystals are aligned in the same direction, there is no light that passes through the lens. However, when some of the crystals are at various angles, corresponding predictable patterns of color are reflected back. This will give information as to the folding of the ice.