An in situ sampling thermal probe for studying global ice sheets

This dissertation describes a measurement device called the thermal probe. The thermal probe is a melt sonde; the probe uses heaters to melt into glacial ice and provides in situ sampling of the meltwater conductivity and particulates. Gravity is the primary mover, but several techniques are described for keeping the probe vertically stabilized during descent. When the probe is intentionally frozen into the ice at a known depth, monitoring the probe orientation and temperature indicates the glacial ice properties at that depth. Knowledge of these basic ice properties are valuable in determining past climate history, but more importantly, the thermal probe is a valuable surveying tool for location of deep drill sites for more precise but costly ice core studies.; The details of fabricating a thermal probe are contained in this dissertation. Test data are included to support the design of the probe. A proposal for a new generation probe is presented based on the performance of past probes.