This information allows us to understand how the ice sheet flow patterns are shifting, which is important for us to know if we are to predict if the ice sheet is stable or not. GPS station at one of the ice core sites. Photograph courtesy of Erik R. Venteris, The Ohio State University. When we get to the field site, we have to drill holes to set our markers. This is done with electric power drills.
Electricity is provided by a small gas generator.
These drills do not turn, but use heat to melt through the ice. The marker must freeze in the hole in order to be stable for a long time. The marker is placed in a bag full of water an dropped in the hole. After the marker freezes in, we pull the wire tight and put a mark on the wire. We will return next year to relocate the marker and measure how far it has moved down in the ice.