Figure 5-29 RIVUXG Disappearing Glacier At an altitude of about 7000 ft (2100 m), Grinnell Glacier is a centerpiece in Montana’s Glacier National Park. It is evident in this series of pictures that this glacier has lost about 40% of its size just since 1966 and, at its current melting rate, will disappear by the year 2030, along with all of the other glaciers in the park.