The altitude of this boundary is referred to as equilibrium line altitude. (climatehotmap.org)
From the head of the glacier at 1300 m to the mean Equilibrium Line Altitude (ELA) at an elevation of 1050 - 1100 m the glacier flows northward. (nichols.edu)
Additional data often mapped by satellite and added to glacier inventories include changing ice debris cover20, rock glaciers21, equilibrium line altitude22, grounding zones23 and glacial lake extent24, 25. (antarcticglaciers.org)