The mass balance of a glacier refers to the balance between the mass that accumulates in the winter and the mass that melts in the winter, according to Iceland On the Web.
The accumulation zone is located high on the glacial mass, where snow remains through the year. Snow melts near the glacier's foot or terminus. The climate determines the area and size of a glacier, according to Iceland On the Web.
Whatever the extent of the accumulation zone, gravity causes the movement of ice down the glacial mass. This occurs constantly, even if the foot of the glacier does not actually move.
