Below is a schematic of the mass balance station.
The temperature sensors are spaced at 10 cm intervals inside a stainless steel pole.
The pole can be positioned so that some of the upper sensors are in the air, although in the current installation the top sensor is located just below the ice surface. The lower sensors will initially be in the water.
The lower sensors gradually freeze into the thickening sea ice cover until the entire pole is frozen in the ice. This typically occurs sometime in late August.
Once this occurs the station can no longer report on the thickness of the sea ice, however, it can still give important information on the temperature gradient within the sea ice.