Freshwater ice thickness apparatus based on differences in electrical resistance and temperature

- An ice thickness apparatus based on electrical resistance difference was presented.
- The electrical resistance difference of medium 12 to − 55 °C was studied in the lab.
- The least square method and change-point theory were proposed to process data.
- The apparatus was tested in Wanjiazhai Reservoir in Yellow River.

An apparatus for monitoring freshwater ice thickness using the differences in the electrical resistance and the temperature of air, ice, and water is developed. The principle and components of the apparatus are presented. Using the proposed apparatus, the electrical resistance characteristics of air, ice, and water from 12 to − 55 °C were studied in the laboratory. Field measurements using this apparatus were conducted in the Wanjiazhai Reservoir in the upper Yellow River for approximately four months during the winter of 2012-2013. The results showed that the recorded ice thickness agreed with the drill-hole measurements. The differences between the recorded and the drill-hole data are between 0 and 0.02 m. The new apparatus can continuously and automatically operate in freshwater ice. It provides an effective method for monitoring the ice thickness and temperature profiles in the air, ice and underlying water.