18 June 2007
Measuring the ice thickness
Integrated to the DAMOCLES program, the EM31 is a piece of equipment that allows measuring the ice thickness.
Last April, during my stay in Barneo, a Russian base in Arctic, I was briefed by Christian Hass (ice specialist in the German, Alfred Wagener Institute).
Once a week, Minh-Ly (our doctor) and I, follow the 3 kilometres long validation line, pulling the EM31 rigged in a pulka (sledge). Every 10 meters, we record the snow and the ice thickness.
The snow thickness is manually measured using a graduated stick. The ice thickness is calculated using electromagnetic conductivity measured by the EM31.
These ice measurements are verified by drilling and manually measuring the thickness at several points along the line. The average thickness is 2 metres. It can get up to 10 meters in pressure ridges.
The main aim of these measurements is to study the evolution of an ice flow over a long period of time. It is not always easy as this line is constantly changing aspect and sometimes getting shorter. This is due to the ice moving and the temperature getting warmer.
These measurements will be used for feeding models and for fine tuning the data received from a number of satellites and other pieces of equipment.